1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2015 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
25 #include "nat/linux-nat.h"
26 #include "nat/linux-waitpid.h"
28 #include <sys/ptrace.h>
29 #include "nat/linux-ptrace.h"
30 #include "nat/linux-procfs.h"
31 #include "nat/linux-personality.h"
33 #include <sys/ioctl.h>
36 #include <sys/syscall.h>
40 #include <sys/types.h>
45 #include "filestuff.h"
46 #include "tracepoint.h"
49 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
50 then ELFMAG0 will have been defined. If it didn't get included by
51 gdb_proc_service.h then including it will likely introduce a duplicate
52 definition of elf_fpregset_t. */
55 #include "nat/linux-namespaces.h"
58 #define SPUFS_MAGIC 0x23c9b64e
61 #ifdef HAVE_PERSONALITY
62 # include <sys/personality.h>
63 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
64 # define ADDR_NO_RANDOMIZE 0x0040000
73 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
76 /* This is the kernel's hard limit. Not to be confused with
82 /* Some targets did not define these ptrace constants from the start,
83 so gdbserver defines them locally here. In the future, these may
84 be removed after they are added to asm/ptrace.h. */
85 #if !(defined(PT_TEXT_ADDR) \
86 || defined(PT_DATA_ADDR) \
87 || defined(PT_TEXT_END_ADDR))
88 #if defined(__mcoldfire__)
89 /* These are still undefined in 3.10 kernels. */
90 #define PT_TEXT_ADDR 49*4
91 #define PT_DATA_ADDR 50*4
92 #define PT_TEXT_END_ADDR 51*4
93 /* BFIN already defines these since at least 2.6.32 kernels. */
95 #define PT_TEXT_ADDR 220
96 #define PT_TEXT_END_ADDR 224
97 #define PT_DATA_ADDR 228
98 /* These are still undefined in 3.10 kernels. */
99 #elif defined(__TMS320C6X__)
100 #define PT_TEXT_ADDR (0x10000*4)
101 #define PT_DATA_ADDR (0x10004*4)
102 #define PT_TEXT_END_ADDR (0x10008*4)
106 #ifdef HAVE_LINUX_BTRACE
107 # include "nat/linux-btrace.h"
108 # include "btrace-common.h"
111 #ifndef HAVE_ELF32_AUXV_T
112 /* Copied from glibc's elf.h. */
115 uint32_t a_type
; /* Entry type */
118 uint32_t a_val
; /* Integer value */
119 /* We use to have pointer elements added here. We cannot do that,
120 though, since it does not work when using 32-bit definitions
121 on 64-bit platforms and vice versa. */
126 #ifndef HAVE_ELF64_AUXV_T
127 /* Copied from glibc's elf.h. */
130 uint64_t a_type
; /* Entry type */
133 uint64_t a_val
; /* Integer value */
134 /* We use to have pointer elements added here. We cannot do that,
135 though, since it does not work when using 32-bit definitions
136 on 64-bit platforms and vice versa. */
143 /* See nat/linux-nat.h. */
146 ptid_of_lwp (struct lwp_info
*lwp
)
148 return ptid_of (get_lwp_thread (lwp
));
151 /* See nat/linux-nat.h. */
154 lwp_set_arch_private_info (struct lwp_info
*lwp
,
155 struct arch_lwp_info
*info
)
157 lwp
->arch_private
= info
;
160 /* See nat/linux-nat.h. */
162 struct arch_lwp_info
*
163 lwp_arch_private_info (struct lwp_info
*lwp
)
165 return lwp
->arch_private
;
168 /* See nat/linux-nat.h. */
171 lwp_is_stopped (struct lwp_info
*lwp
)
176 /* See nat/linux-nat.h. */
178 enum target_stop_reason
179 lwp_stop_reason (struct lwp_info
*lwp
)
181 return lwp
->stop_reason
;
184 /* A list of all unknown processes which receive stop signals. Some
185 other process will presumably claim each of these as forked
186 children momentarily. */
188 struct simple_pid_list
190 /* The process ID. */
193 /* The status as reported by waitpid. */
197 struct simple_pid_list
*next
;
199 struct simple_pid_list
*stopped_pids
;
201 /* Trivial list manipulation functions to keep track of a list of new
202 stopped processes. */
205 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
207 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
210 new_pid
->status
= status
;
211 new_pid
->next
= *listp
;
216 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
218 struct simple_pid_list
**p
;
220 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
221 if ((*p
)->pid
== pid
)
223 struct simple_pid_list
*next
= (*p
)->next
;
225 *statusp
= (*p
)->status
;
233 enum stopping_threads_kind
235 /* Not stopping threads presently. */
236 NOT_STOPPING_THREADS
,
238 /* Stopping threads. */
241 /* Stopping and suspending threads. */
242 STOPPING_AND_SUSPENDING_THREADS
245 /* This is set while stop_all_lwps is in effect. */
246 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
248 /* FIXME make into a target method? */
249 int using_threads
= 1;
251 /* True if we're presently stabilizing threads (moving them out of
253 static int stabilizing_threads
;
255 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
256 int step
, int signal
, siginfo_t
*info
);
257 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
258 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
259 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
260 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
261 int *wstat
, int options
);
262 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
263 static struct lwp_info
*add_lwp (ptid_t ptid
);
264 static int linux_stopped_by_watchpoint (void);
265 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
266 static void proceed_all_lwps (void);
267 static int finish_step_over (struct lwp_info
*lwp
);
268 static int kill_lwp (unsigned long lwpid
, int signo
);
270 /* When the event-loop is doing a step-over, this points at the thread
272 ptid_t step_over_bkpt
;
274 /* True if the low target can hardware single-step. Such targets
275 don't need a BREAKPOINT_REINSERT_ADDR callback. */
278 can_hardware_single_step (void)
280 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
283 /* True if the low target supports memory breakpoints. If so, we'll
284 have a GET_PC implementation. */
287 supports_breakpoints (void)
289 return (the_low_target
.get_pc
!= NULL
);
292 /* Returns true if this target can support fast tracepoints. This
293 does not mean that the in-process agent has been loaded in the
297 supports_fast_tracepoints (void)
299 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
302 /* True if LWP is stopped in its stepping range. */
305 lwp_in_step_range (struct lwp_info
*lwp
)
307 CORE_ADDR pc
= lwp
->stop_pc
;
309 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
312 struct pending_signals
316 struct pending_signals
*prev
;
319 /* The read/write ends of the pipe registered as waitable file in the
321 static int linux_event_pipe
[2] = { -1, -1 };
323 /* True if we're currently in async mode. */
324 #define target_is_async_p() (linux_event_pipe[0] != -1)
326 static void send_sigstop (struct lwp_info
*lwp
);
327 static void wait_for_sigstop (void);
329 /* Return non-zero if HEADER is a 64-bit ELF file. */
332 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
334 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
335 && header
->e_ident
[EI_MAG1
] == ELFMAG1
336 && header
->e_ident
[EI_MAG2
] == ELFMAG2
337 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
339 *machine
= header
->e_machine
;
340 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
347 /* Return non-zero if FILE is a 64-bit ELF file,
348 zero if the file is not a 64-bit ELF file,
349 and -1 if the file is not accessible or doesn't exist. */
352 elf_64_file_p (const char *file
, unsigned int *machine
)
357 fd
= open (file
, O_RDONLY
);
361 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
368 return elf_64_header_p (&header
, machine
);
371 /* Accepts an integer PID; Returns true if the executable PID is
372 running is a 64-bit ELF file.. */
375 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
379 sprintf (file
, "/proc/%d/exe", pid
);
380 return elf_64_file_p (file
, machine
);
384 delete_lwp (struct lwp_info
*lwp
)
386 struct thread_info
*thr
= get_lwp_thread (lwp
);
389 debug_printf ("deleting %ld\n", lwpid_of (thr
));
392 free (lwp
->arch_private
);
396 /* Add a process to the common process list, and set its private
399 static struct process_info
*
400 linux_add_process (int pid
, int attached
)
402 struct process_info
*proc
;
404 proc
= add_process (pid
, attached
);
405 proc
->priv
= xcalloc (1, sizeof (*proc
->priv
));
407 /* Set the arch when the first LWP stops. */
408 proc
->priv
->new_inferior
= 1;
410 if (the_low_target
.new_process
!= NULL
)
411 proc
->priv
->arch_private
= the_low_target
.new_process ();
416 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
418 /* Handle a GNU/Linux extended wait response. If we see a clone
419 event, we need to add the new LWP to our list (and return 0 so as
420 not to report the trap to higher layers). */
423 handle_extended_wait (struct lwp_info
*event_lwp
, int wstat
)
425 int event
= linux_ptrace_get_extended_event (wstat
);
426 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
427 struct lwp_info
*new_lwp
;
429 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
430 || (event
== PTRACE_EVENT_CLONE
))
433 unsigned long new_pid
;
436 /* Get the pid of the new lwp. */
437 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
440 /* If we haven't already seen the new PID stop, wait for it now. */
441 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
443 /* The new child has a pending SIGSTOP. We can't affect it until it
444 hits the SIGSTOP, but we're already attached. */
446 ret
= my_waitpid (new_pid
, &status
, __WALL
);
449 perror_with_name ("waiting for new child");
450 else if (ret
!= new_pid
)
451 warning ("wait returned unexpected PID %d", ret
);
452 else if (!WIFSTOPPED (status
))
453 warning ("wait returned unexpected status 0x%x", status
);
456 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
458 struct process_info
*parent_proc
;
459 struct process_info
*child_proc
;
460 struct lwp_info
*child_lwp
;
461 struct thread_info
*child_thr
;
462 struct target_desc
*tdesc
;
464 ptid
= ptid_build (new_pid
, new_pid
, 0);
468 debug_printf ("HEW: Got fork event from LWP %ld, "
470 ptid_get_lwp (ptid_of (event_thr
)),
471 ptid_get_pid (ptid
));
474 /* Add the new process to the tables and clone the breakpoint
475 lists of the parent. We need to do this even if the new process
476 will be detached, since we will need the process object and the
477 breakpoints to remove any breakpoints from memory when we
478 detach, and the client side will access registers. */
479 child_proc
= linux_add_process (new_pid
, 0);
480 gdb_assert (child_proc
!= NULL
);
481 child_lwp
= add_lwp (ptid
);
482 gdb_assert (child_lwp
!= NULL
);
483 child_lwp
->stopped
= 1;
484 child_lwp
->must_set_ptrace_flags
= 1;
485 child_lwp
->status_pending_p
= 0;
486 child_thr
= get_lwp_thread (child_lwp
);
487 child_thr
->last_resume_kind
= resume_stop
;
488 parent_proc
= get_thread_process (event_thr
);
489 child_proc
->attached
= parent_proc
->attached
;
490 clone_all_breakpoints (&child_proc
->breakpoints
,
491 &child_proc
->raw_breakpoints
,
492 parent_proc
->breakpoints
);
494 tdesc
= xmalloc (sizeof (struct target_desc
));
495 copy_target_description (tdesc
, parent_proc
->tdesc
);
496 child_proc
->tdesc
= tdesc
;
498 /* Clone arch-specific process data. */
499 if (the_low_target
.new_fork
!= NULL
)
500 the_low_target
.new_fork (parent_proc
, child_proc
);
502 /* Save fork info in the parent thread. */
503 if (event
== PTRACE_EVENT_FORK
)
504 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
505 else if (event
== PTRACE_EVENT_VFORK
)
506 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
508 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
510 /* The status_pending field contains bits denoting the
511 extended event, so when the pending event is handled,
512 the handler will look at lwp->waitstatus. */
513 event_lwp
->status_pending_p
= 1;
514 event_lwp
->status_pending
= wstat
;
516 /* Report the event. */
521 debug_printf ("HEW: Got clone event "
522 "from LWP %ld, new child is LWP %ld\n",
523 lwpid_of (event_thr
), new_pid
);
525 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
526 new_lwp
= add_lwp (ptid
);
528 /* Either we're going to immediately resume the new thread
529 or leave it stopped. linux_resume_one_lwp is a nop if it
530 thinks the thread is currently running, so set this first
531 before calling linux_resume_one_lwp. */
532 new_lwp
->stopped
= 1;
534 /* If we're suspending all threads, leave this one suspended
536 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
537 new_lwp
->suspended
= 1;
539 /* Normally we will get the pending SIGSTOP. But in some cases
540 we might get another signal delivered to the group first.
541 If we do get another signal, be sure not to lose it. */
542 if (WSTOPSIG (status
) != SIGSTOP
)
544 new_lwp
->stop_expected
= 1;
545 new_lwp
->status_pending_p
= 1;
546 new_lwp
->status_pending
= status
;
549 /* Don't report the event. */
552 else if (event
== PTRACE_EVENT_VFORK_DONE
)
554 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
556 /* Report the event. */
560 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
563 /* Return the PC as read from the regcache of LWP, without any
567 get_pc (struct lwp_info
*lwp
)
569 struct thread_info
*saved_thread
;
570 struct regcache
*regcache
;
573 if (the_low_target
.get_pc
== NULL
)
576 saved_thread
= current_thread
;
577 current_thread
= get_lwp_thread (lwp
);
579 regcache
= get_thread_regcache (current_thread
, 1);
580 pc
= (*the_low_target
.get_pc
) (regcache
);
583 debug_printf ("pc is 0x%lx\n", (long) pc
);
585 current_thread
= saved_thread
;
589 /* This function should only be called if LWP got a SIGTRAP.
590 The SIGTRAP could mean several things.
592 On i386, where decr_pc_after_break is non-zero:
594 If we were single-stepping this process using PTRACE_SINGLESTEP, we
595 will get only the one SIGTRAP. The value of $eip will be the next
596 instruction. If the instruction we stepped over was a breakpoint,
597 we need to decrement the PC.
599 If we continue the process using PTRACE_CONT, we will get a
600 SIGTRAP when we hit a breakpoint. The value of $eip will be
601 the instruction after the breakpoint (i.e. needs to be
602 decremented). If we report the SIGTRAP to GDB, we must also
603 report the undecremented PC. If the breakpoint is removed, we
604 must resume at the decremented PC.
606 On a non-decr_pc_after_break machine with hardware or kernel
609 If we either single-step a breakpoint instruction, or continue and
610 hit a breakpoint instruction, our PC will point at the breakpoint
614 check_stopped_by_breakpoint (struct lwp_info
*lwp
)
617 CORE_ADDR sw_breakpoint_pc
;
618 struct thread_info
*saved_thread
;
619 #if USE_SIGTRAP_SIGINFO
623 if (the_low_target
.get_pc
== NULL
)
627 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
629 /* breakpoint_at reads from the current thread. */
630 saved_thread
= current_thread
;
631 current_thread
= get_lwp_thread (lwp
);
633 #if USE_SIGTRAP_SIGINFO
634 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
635 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
637 if (siginfo
.si_signo
== SIGTRAP
)
639 if (siginfo
.si_code
== GDB_ARCH_TRAP_BRKPT
)
643 struct thread_info
*thr
= get_lwp_thread (lwp
);
645 debug_printf ("CSBB: %s stopped by software breakpoint\n",
646 target_pid_to_str (ptid_of (thr
)));
649 /* Back up the PC if necessary. */
650 if (pc
!= sw_breakpoint_pc
)
652 struct regcache
*regcache
653 = get_thread_regcache (current_thread
, 1);
654 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
657 lwp
->stop_pc
= sw_breakpoint_pc
;
658 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
659 current_thread
= saved_thread
;
662 else if (siginfo
.si_code
== TRAP_HWBKPT
)
666 struct thread_info
*thr
= get_lwp_thread (lwp
);
668 debug_printf ("CSBB: %s stopped by hardware "
669 "breakpoint/watchpoint\n",
670 target_pid_to_str (ptid_of (thr
)));
674 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
675 current_thread
= saved_thread
;
678 else if (siginfo
.si_code
== TRAP_TRACE
)
682 struct thread_info
*thr
= get_lwp_thread (lwp
);
684 debug_printf ("CSBB: %s stopped by trace\n",
685 target_pid_to_str (ptid_of (thr
)));
691 /* We may have just stepped a breakpoint instruction. E.g., in
692 non-stop mode, GDB first tells the thread A to step a range, and
693 then the user inserts a breakpoint inside the range. In that
694 case we need to report the breakpoint PC. */
695 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
696 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
700 struct thread_info
*thr
= get_lwp_thread (lwp
);
702 debug_printf ("CSBB: %s stopped by software breakpoint\n",
703 target_pid_to_str (ptid_of (thr
)));
706 /* Back up the PC if necessary. */
707 if (pc
!= sw_breakpoint_pc
)
709 struct regcache
*regcache
710 = get_thread_regcache (current_thread
, 1);
711 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
714 lwp
->stop_pc
= sw_breakpoint_pc
;
715 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
716 current_thread
= saved_thread
;
720 if (hardware_breakpoint_inserted_here (pc
))
724 struct thread_info
*thr
= get_lwp_thread (lwp
);
726 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
727 target_pid_to_str (ptid_of (thr
)));
731 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
732 current_thread
= saved_thread
;
737 current_thread
= saved_thread
;
741 static struct lwp_info
*
742 add_lwp (ptid_t ptid
)
744 struct lwp_info
*lwp
;
746 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
747 memset (lwp
, 0, sizeof (*lwp
));
749 if (the_low_target
.new_thread
!= NULL
)
750 the_low_target
.new_thread (lwp
);
752 lwp
->thread
= add_thread (ptid
, lwp
);
757 /* Start an inferior process and returns its pid.
758 ALLARGS is a vector of program-name and args. */
761 linux_create_inferior (char *program
, char **allargs
)
763 struct lwp_info
*new_lwp
;
766 struct cleanup
*restore_personality
767 = maybe_disable_address_space_randomization (disable_randomization
);
769 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
775 perror_with_name ("fork");
780 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
782 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
783 signal (__SIGRTMIN
+ 1, SIG_DFL
);
788 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
789 stdout to stderr so that inferior i/o doesn't corrupt the connection.
790 Also, redirect stdin to /dev/null. */
791 if (remote_connection_is_stdio ())
794 open ("/dev/null", O_RDONLY
);
796 if (write (2, "stdin/stdout redirected\n",
797 sizeof ("stdin/stdout redirected\n") - 1) < 0)
799 /* Errors ignored. */;
803 execv (program
, allargs
);
805 execvp (program
, allargs
);
807 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
813 do_cleanups (restore_personality
);
815 linux_add_process (pid
, 0);
817 ptid
= ptid_build (pid
, pid
, 0);
818 new_lwp
= add_lwp (ptid
);
819 new_lwp
->must_set_ptrace_flags
= 1;
824 /* Attach to an inferior process. Returns 0 on success, ERRNO on
828 linux_attach_lwp (ptid_t ptid
)
830 struct lwp_info
*new_lwp
;
831 int lwpid
= ptid_get_lwp (ptid
);
833 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
837 new_lwp
= add_lwp (ptid
);
839 /* We need to wait for SIGSTOP before being able to make the next
840 ptrace call on this LWP. */
841 new_lwp
->must_set_ptrace_flags
= 1;
843 if (linux_proc_pid_is_stopped (lwpid
))
846 debug_printf ("Attached to a stopped process\n");
848 /* The process is definitely stopped. It is in a job control
849 stop, unless the kernel predates the TASK_STOPPED /
850 TASK_TRACED distinction, in which case it might be in a
851 ptrace stop. Make sure it is in a ptrace stop; from there we
852 can kill it, signal it, et cetera.
854 First make sure there is a pending SIGSTOP. Since we are
855 already attached, the process can not transition from stopped
856 to running without a PTRACE_CONT; so we know this signal will
857 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
858 probably already in the queue (unless this kernel is old
859 enough to use TASK_STOPPED for ptrace stops); but since
860 SIGSTOP is not an RT signal, it can only be queued once. */
861 kill_lwp (lwpid
, SIGSTOP
);
863 /* Finally, resume the stopped process. This will deliver the
864 SIGSTOP (or a higher priority signal, just like normal
865 PTRACE_ATTACH), which we'll catch later on. */
866 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
869 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
872 There are several cases to consider here:
874 1) gdbserver has already attached to the process and is being notified
875 of a new thread that is being created.
876 In this case we should ignore that SIGSTOP and resume the
877 process. This is handled below by setting stop_expected = 1,
878 and the fact that add_thread sets last_resume_kind ==
881 2) This is the first thread (the process thread), and we're attaching
882 to it via attach_inferior.
883 In this case we want the process thread to stop.
884 This is handled by having linux_attach set last_resume_kind ==
885 resume_stop after we return.
887 If the pid we are attaching to is also the tgid, we attach to and
888 stop all the existing threads. Otherwise, we attach to pid and
889 ignore any other threads in the same group as this pid.
891 3) GDB is connecting to gdbserver and is requesting an enumeration of all
893 In this case we want the thread to stop.
894 FIXME: This case is currently not properly handled.
895 We should wait for the SIGSTOP but don't. Things work apparently
896 because enough time passes between when we ptrace (ATTACH) and when
897 gdb makes the next ptrace call on the thread.
899 On the other hand, if we are currently trying to stop all threads, we
900 should treat the new thread as if we had sent it a SIGSTOP. This works
901 because we are guaranteed that the add_lwp call above added us to the
902 end of the list, and so the new thread has not yet reached
903 wait_for_sigstop (but will). */
904 new_lwp
->stop_expected
= 1;
909 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
910 already attached. Returns true if a new LWP is found, false
914 attach_proc_task_lwp_callback (ptid_t ptid
)
916 /* Is this a new thread? */
917 if (find_thread_ptid (ptid
) == NULL
)
919 int lwpid
= ptid_get_lwp (ptid
);
923 debug_printf ("Found new lwp %d\n", lwpid
);
925 err
= linux_attach_lwp (ptid
);
927 /* Be quiet if we simply raced with the thread exiting. EPERM
928 is returned if the thread's task still exists, and is marked
929 as exited or zombie, as well as other conditions, so in that
930 case, confirm the status in /proc/PID/status. */
932 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
936 debug_printf ("Cannot attach to lwp %d: "
937 "thread is gone (%d: %s)\n",
938 lwpid
, err
, strerror (err
));
943 warning (_("Cannot attach to lwp %d: %s"),
945 linux_ptrace_attach_fail_reason_string (ptid
, err
));
953 /* Attach to PID. If PID is the tgid, attach to it and all
957 linux_attach (unsigned long pid
)
959 ptid_t ptid
= ptid_build (pid
, pid
, 0);
962 /* Attach to PID. We will check for other threads
964 err
= linux_attach_lwp (ptid
);
966 error ("Cannot attach to process %ld: %s",
967 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
969 linux_add_process (pid
, 1);
973 struct thread_info
*thread
;
975 /* Don't ignore the initial SIGSTOP if we just attached to this
976 process. It will be collected by wait shortly. */
977 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
978 thread
->last_resume_kind
= resume_stop
;
981 /* We must attach to every LWP. If /proc is mounted, use that to
982 find them now. On the one hand, the inferior may be using raw
983 clone instead of using pthreads. On the other hand, even if it
984 is using pthreads, GDB may not be connected yet (thread_db needs
985 to do symbol lookups, through qSymbol). Also, thread_db walks
986 structures in the inferior's address space to find the list of
987 threads/LWPs, and those structures may well be corrupted. Note
988 that once thread_db is loaded, we'll still use it to list threads
989 and associate pthread info with each LWP. */
990 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1001 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
1003 struct counter
*counter
= args
;
1005 if (ptid_get_pid (entry
->id
) == counter
->pid
)
1007 if (++counter
->count
> 1)
1015 last_thread_of_process_p (int pid
)
1017 struct counter counter
= { pid
, 0 };
1019 return (find_inferior (&all_threads
,
1020 second_thread_of_pid_p
, &counter
) == NULL
);
1026 linux_kill_one_lwp (struct lwp_info
*lwp
)
1028 struct thread_info
*thr
= get_lwp_thread (lwp
);
1029 int pid
= lwpid_of (thr
);
1031 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1032 there is no signal context, and ptrace(PTRACE_KILL) (or
1033 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1034 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1035 alternative is to kill with SIGKILL. We only need one SIGKILL
1036 per process, not one for each thread. But since we still support
1037 linuxthreads, and we also support debugging programs using raw
1038 clone without CLONE_THREAD, we send one for each thread. For
1039 years, we used PTRACE_KILL only, so we're being a bit paranoid
1040 about some old kernels where PTRACE_KILL might work better
1041 (dubious if there are any such, but that's why it's paranoia), so
1042 we try SIGKILL first, PTRACE_KILL second, and so we're fine
1046 kill_lwp (pid
, SIGKILL
);
1049 int save_errno
= errno
;
1051 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1052 target_pid_to_str (ptid_of (thr
)),
1053 save_errno
? strerror (save_errno
) : "OK");
1057 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1060 int save_errno
= errno
;
1062 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1063 target_pid_to_str (ptid_of (thr
)),
1064 save_errno
? strerror (save_errno
) : "OK");
1068 /* Kill LWP and wait for it to die. */
1071 kill_wait_lwp (struct lwp_info
*lwp
)
1073 struct thread_info
*thr
= get_lwp_thread (lwp
);
1074 int pid
= ptid_get_pid (ptid_of (thr
));
1075 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1080 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1084 linux_kill_one_lwp (lwp
);
1086 /* Make sure it died. Notes:
1088 - The loop is most likely unnecessary.
1090 - We don't use linux_wait_for_event as that could delete lwps
1091 while we're iterating over them. We're not interested in
1092 any pending status at this point, only in making sure all
1093 wait status on the kernel side are collected until the
1096 - We don't use __WALL here as the __WALL emulation relies on
1097 SIGCHLD, and killing a stopped process doesn't generate
1098 one, nor an exit status.
1100 res
= my_waitpid (lwpid
, &wstat
, 0);
1101 if (res
== -1 && errno
== ECHILD
)
1102 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1103 } while (res
> 0 && WIFSTOPPED (wstat
));
1105 gdb_assert (res
> 0);
1108 /* Callback for `find_inferior'. Kills an lwp of a given process,
1109 except the leader. */
1112 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
1114 struct thread_info
*thread
= (struct thread_info
*) entry
;
1115 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1116 int pid
= * (int *) args
;
1118 if (ptid_get_pid (entry
->id
) != pid
)
1121 /* We avoid killing the first thread here, because of a Linux kernel (at
1122 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1123 the children get a chance to be reaped, it will remain a zombie
1126 if (lwpid_of (thread
) == pid
)
1129 debug_printf ("lkop: is last of process %s\n",
1130 target_pid_to_str (entry
->id
));
1134 kill_wait_lwp (lwp
);
1139 linux_kill (int pid
)
1141 struct process_info
*process
;
1142 struct lwp_info
*lwp
;
1144 process
= find_process_pid (pid
);
1145 if (process
== NULL
)
1148 /* If we're killing a running inferior, make sure it is stopped
1149 first, as PTRACE_KILL will not work otherwise. */
1150 stop_all_lwps (0, NULL
);
1152 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1154 /* See the comment in linux_kill_one_lwp. We did not kill the first
1155 thread in the list, so do so now. */
1156 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1161 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1165 kill_wait_lwp (lwp
);
1167 the_target
->mourn (process
);
1169 /* Since we presently can only stop all lwps of all processes, we
1170 need to unstop lwps of other processes. */
1171 unstop_all_lwps (0, NULL
);
1175 /* Get pending signal of THREAD, for detaching purposes. This is the
1176 signal the thread last stopped for, which we need to deliver to the
1177 thread when detaching, otherwise, it'd be suppressed/lost. */
1180 get_detach_signal (struct thread_info
*thread
)
1182 enum gdb_signal signo
= GDB_SIGNAL_0
;
1184 struct lwp_info
*lp
= get_thread_lwp (thread
);
1186 if (lp
->status_pending_p
)
1187 status
= lp
->status_pending
;
1190 /* If the thread had been suspended by gdbserver, and it stopped
1191 cleanly, then it'll have stopped with SIGSTOP. But we don't
1192 want to deliver that SIGSTOP. */
1193 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1194 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1197 /* Otherwise, we may need to deliver the signal we
1199 status
= lp
->last_status
;
1202 if (!WIFSTOPPED (status
))
1205 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1206 target_pid_to_str (ptid_of (thread
)));
1210 /* Extended wait statuses aren't real SIGTRAPs. */
1211 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1214 debug_printf ("GPS: lwp %s had stopped with extended "
1215 "status: no pending signal\n",
1216 target_pid_to_str (ptid_of (thread
)));
1220 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1222 if (program_signals_p
&& !program_signals
[signo
])
1225 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1226 target_pid_to_str (ptid_of (thread
)),
1227 gdb_signal_to_string (signo
));
1230 else if (!program_signals_p
1231 /* If we have no way to know which signals GDB does not
1232 want to have passed to the program, assume
1233 SIGTRAP/SIGINT, which is GDB's default. */
1234 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1237 debug_printf ("GPS: lwp %s had signal %s, "
1238 "but we don't know if we should pass it. "
1239 "Default to not.\n",
1240 target_pid_to_str (ptid_of (thread
)),
1241 gdb_signal_to_string (signo
));
1247 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1248 target_pid_to_str (ptid_of (thread
)),
1249 gdb_signal_to_string (signo
));
1251 return WSTOPSIG (status
);
1256 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1258 struct thread_info
*thread
= (struct thread_info
*) entry
;
1259 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1260 int pid
= * (int *) args
;
1263 if (ptid_get_pid (entry
->id
) != pid
)
1266 /* If there is a pending SIGSTOP, get rid of it. */
1267 if (lwp
->stop_expected
)
1270 debug_printf ("Sending SIGCONT to %s\n",
1271 target_pid_to_str (ptid_of (thread
)));
1273 kill_lwp (lwpid_of (thread
), SIGCONT
);
1274 lwp
->stop_expected
= 0;
1277 /* Flush any pending changes to the process's registers. */
1278 regcache_invalidate_thread (thread
);
1280 /* Pass on any pending signal for this thread. */
1281 sig
= get_detach_signal (thread
);
1283 /* Finally, let it resume. */
1284 if (the_low_target
.prepare_to_resume
!= NULL
)
1285 the_low_target
.prepare_to_resume (lwp
);
1286 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1287 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1288 error (_("Can't detach %s: %s"),
1289 target_pid_to_str (ptid_of (thread
)),
1297 linux_detach (int pid
)
1299 struct process_info
*process
;
1301 process
= find_process_pid (pid
);
1302 if (process
== NULL
)
1305 /* Stop all threads before detaching. First, ptrace requires that
1306 the thread is stopped to sucessfully detach. Second, thread_db
1307 may need to uninstall thread event breakpoints from memory, which
1308 only works with a stopped process anyway. */
1309 stop_all_lwps (0, NULL
);
1311 #ifdef USE_THREAD_DB
1312 thread_db_detach (process
);
1315 /* Stabilize threads (move out of jump pads). */
1316 stabilize_threads ();
1318 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1320 the_target
->mourn (process
);
1322 /* Since we presently can only stop all lwps of all processes, we
1323 need to unstop lwps of other processes. */
1324 unstop_all_lwps (0, NULL
);
1328 /* Remove all LWPs that belong to process PROC from the lwp list. */
1331 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1333 struct thread_info
*thread
= (struct thread_info
*) entry
;
1334 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1335 struct process_info
*process
= proc
;
1337 if (pid_of (thread
) == pid_of (process
))
1344 linux_mourn (struct process_info
*process
)
1346 struct process_info_private
*priv
;
1348 #ifdef USE_THREAD_DB
1349 thread_db_mourn (process
);
1352 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1354 /* Freeing all private data. */
1355 priv
= process
->priv
;
1356 free (priv
->arch_private
);
1358 process
->priv
= NULL
;
1360 remove_process (process
);
1364 linux_join (int pid
)
1369 ret
= my_waitpid (pid
, &status
, 0);
1370 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1372 } while (ret
!= -1 || errno
!= ECHILD
);
1375 /* Return nonzero if the given thread is still alive. */
1377 linux_thread_alive (ptid_t ptid
)
1379 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1381 /* We assume we always know if a thread exits. If a whole process
1382 exited but we still haven't been able to report it to GDB, we'll
1383 hold on to the last lwp of the dead process. */
1390 /* Return 1 if this lwp still has an interesting status pending. If
1391 not (e.g., it had stopped for a breakpoint that is gone), return
1395 thread_still_has_status_pending_p (struct thread_info
*thread
)
1397 struct lwp_info
*lp
= get_thread_lwp (thread
);
1399 if (!lp
->status_pending_p
)
1402 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1403 report any status pending the LWP may have. */
1404 if (thread
->last_resume_kind
== resume_stop
1405 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1408 if (thread
->last_resume_kind
!= resume_stop
1409 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1410 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1412 struct thread_info
*saved_thread
;
1416 gdb_assert (lp
->last_status
!= 0);
1420 saved_thread
= current_thread
;
1421 current_thread
= thread
;
1423 if (pc
!= lp
->stop_pc
)
1426 debug_printf ("PC of %ld changed\n",
1431 #if !USE_SIGTRAP_SIGINFO
1432 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1433 && !(*the_low_target
.breakpoint_at
) (pc
))
1436 debug_printf ("previous SW breakpoint of %ld gone\n",
1440 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1441 && !hardware_breakpoint_inserted_here (pc
))
1444 debug_printf ("previous HW breakpoint of %ld gone\n",
1450 current_thread
= saved_thread
;
1455 debug_printf ("discarding pending breakpoint status\n");
1456 lp
->status_pending_p
= 0;
1464 /* Return 1 if this lwp has an interesting status pending. */
1466 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1468 struct thread_info
*thread
= (struct thread_info
*) entry
;
1469 struct lwp_info
*lp
= get_thread_lwp (thread
);
1470 ptid_t ptid
= * (ptid_t
*) arg
;
1472 /* Check if we're only interested in events from a specific process
1473 or a specific LWP. */
1474 if (!ptid_match (ptid_of (thread
), ptid
))
1477 if (lp
->status_pending_p
1478 && !thread_still_has_status_pending_p (thread
))
1480 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1484 return lp
->status_pending_p
;
1488 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1490 ptid_t ptid
= *(ptid_t
*) data
;
1493 if (ptid_get_lwp (ptid
) != 0)
1494 lwp
= ptid_get_lwp (ptid
);
1496 lwp
= ptid_get_pid (ptid
);
1498 if (ptid_get_lwp (entry
->id
) == lwp
)
1505 find_lwp_pid (ptid_t ptid
)
1507 struct inferior_list_entry
*thread
1508 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1513 return get_thread_lwp ((struct thread_info
*) thread
);
1516 /* Return the number of known LWPs in the tgid given by PID. */
1521 struct inferior_list_entry
*inf
, *tmp
;
1524 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1526 if (ptid_get_pid (inf
->id
) == pid
)
1533 /* The arguments passed to iterate_over_lwps. */
1535 struct iterate_over_lwps_args
1537 /* The FILTER argument passed to iterate_over_lwps. */
1540 /* The CALLBACK argument passed to iterate_over_lwps. */
1541 iterate_over_lwps_ftype
*callback
;
1543 /* The DATA argument passed to iterate_over_lwps. */
1547 /* Callback for find_inferior used by iterate_over_lwps to filter
1548 calls to the callback supplied to that function. Returning a
1549 nonzero value causes find_inferiors to stop iterating and return
1550 the current inferior_list_entry. Returning zero indicates that
1551 find_inferiors should continue iterating. */
1554 iterate_over_lwps_filter (struct inferior_list_entry
*entry
, void *args_p
)
1556 struct iterate_over_lwps_args
*args
1557 = (struct iterate_over_lwps_args
*) args_p
;
1559 if (ptid_match (entry
->id
, args
->filter
))
1561 struct thread_info
*thr
= (struct thread_info
*) entry
;
1562 struct lwp_info
*lwp
= get_thread_lwp (thr
);
1564 return (*args
->callback
) (lwp
, args
->data
);
1570 /* See nat/linux-nat.h. */
1573 iterate_over_lwps (ptid_t filter
,
1574 iterate_over_lwps_ftype callback
,
1577 struct iterate_over_lwps_args args
= {filter
, callback
, data
};
1578 struct inferior_list_entry
*entry
;
1580 entry
= find_inferior (&all_threads
, iterate_over_lwps_filter
, &args
);
1584 return get_thread_lwp ((struct thread_info
*) entry
);
1587 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1588 their exits until all other threads in the group have exited. */
1591 check_zombie_leaders (void)
1593 struct process_info
*proc
, *tmp
;
1595 ALL_PROCESSES (proc
, tmp
)
1597 pid_t leader_pid
= pid_of (proc
);
1598 struct lwp_info
*leader_lp
;
1600 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1603 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1604 "num_lwps=%d, zombie=%d\n",
1605 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1606 linux_proc_pid_is_zombie (leader_pid
));
1608 if (leader_lp
!= NULL
1609 /* Check if there are other threads in the group, as we may
1610 have raced with the inferior simply exiting. */
1611 && !last_thread_of_process_p (leader_pid
)
1612 && linux_proc_pid_is_zombie (leader_pid
))
1614 /* A leader zombie can mean one of two things:
1616 - It exited, and there's an exit status pending
1617 available, or only the leader exited (not the whole
1618 program). In the latter case, we can't waitpid the
1619 leader's exit status until all other threads are gone.
1621 - There are 3 or more threads in the group, and a thread
1622 other than the leader exec'd. On an exec, the Linux
1623 kernel destroys all other threads (except the execing
1624 one) in the thread group, and resets the execing thread's
1625 tid to the tgid. No exit notification is sent for the
1626 execing thread -- from the ptracer's perspective, it
1627 appears as though the execing thread just vanishes.
1628 Until we reap all other threads except the leader and the
1629 execing thread, the leader will be zombie, and the
1630 execing thread will be in `D (disc sleep)'. As soon as
1631 all other threads are reaped, the execing thread changes
1632 it's tid to the tgid, and the previous (zombie) leader
1633 vanishes, giving place to the "new" leader. We could try
1634 distinguishing the exit and exec cases, by waiting once
1635 more, and seeing if something comes out, but it doesn't
1636 sound useful. The previous leader _does_ go away, and
1637 we'll re-add the new one once we see the exec event
1638 (which is just the same as what would happen if the
1639 previous leader did exit voluntarily before some other
1644 "CZL: Thread group leader %d zombie "
1645 "(it exited, or another thread execd).\n",
1648 delete_lwp (leader_lp
);
1653 /* Callback for `find_inferior'. Returns the first LWP that is not
1654 stopped. ARG is a PTID filter. */
1657 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1659 struct thread_info
*thr
= (struct thread_info
*) entry
;
1660 struct lwp_info
*lwp
;
1661 ptid_t filter
= *(ptid_t
*) arg
;
1663 if (!ptid_match (ptid_of (thr
), filter
))
1666 lwp
= get_thread_lwp (thr
);
1673 /* This function should only be called if the LWP got a SIGTRAP.
1675 Handle any tracepoint steps or hits. Return true if a tracepoint
1676 event was handled, 0 otherwise. */
1679 handle_tracepoints (struct lwp_info
*lwp
)
1681 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1682 int tpoint_related_event
= 0;
1684 gdb_assert (lwp
->suspended
== 0);
1686 /* If this tracepoint hit causes a tracing stop, we'll immediately
1687 uninsert tracepoints. To do this, we temporarily pause all
1688 threads, unpatch away, and then unpause threads. We need to make
1689 sure the unpausing doesn't resume LWP too. */
1692 /* And we need to be sure that any all-threads-stopping doesn't try
1693 to move threads out of the jump pads, as it could deadlock the
1694 inferior (LWP could be in the jump pad, maybe even holding the
1697 /* Do any necessary step collect actions. */
1698 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1700 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1702 /* See if we just hit a tracepoint and do its main collect
1704 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1708 gdb_assert (lwp
->suspended
== 0);
1709 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1711 if (tpoint_related_event
)
1714 debug_printf ("got a tracepoint event\n");
1721 /* Convenience wrapper. Returns true if LWP is presently collecting a
1725 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1726 struct fast_tpoint_collect_status
*status
)
1728 CORE_ADDR thread_area
;
1729 struct thread_info
*thread
= get_lwp_thread (lwp
);
1731 if (the_low_target
.get_thread_area
== NULL
)
1734 /* Get the thread area address. This is used to recognize which
1735 thread is which when tracing with the in-process agent library.
1736 We don't read anything from the address, and treat it as opaque;
1737 it's the address itself that we assume is unique per-thread. */
1738 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1741 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1744 /* The reason we resume in the caller, is because we want to be able
1745 to pass lwp->status_pending as WSTAT, and we need to clear
1746 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1747 refuses to resume. */
1750 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1752 struct thread_info
*saved_thread
;
1754 saved_thread
= current_thread
;
1755 current_thread
= get_lwp_thread (lwp
);
1758 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1759 && supports_fast_tracepoints ()
1760 && agent_loaded_p ())
1762 struct fast_tpoint_collect_status status
;
1766 debug_printf ("Checking whether LWP %ld needs to move out of the "
1768 lwpid_of (current_thread
));
1770 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1773 || (WSTOPSIG (*wstat
) != SIGILL
1774 && WSTOPSIG (*wstat
) != SIGFPE
1775 && WSTOPSIG (*wstat
) != SIGSEGV
1776 && WSTOPSIG (*wstat
) != SIGBUS
))
1778 lwp
->collecting_fast_tracepoint
= r
;
1782 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1784 /* Haven't executed the original instruction yet.
1785 Set breakpoint there, and wait till it's hit,
1786 then single-step until exiting the jump pad. */
1787 lwp
->exit_jump_pad_bkpt
1788 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1792 debug_printf ("Checking whether LWP %ld needs to move out of "
1793 "the jump pad...it does\n",
1794 lwpid_of (current_thread
));
1795 current_thread
= saved_thread
;
1802 /* If we get a synchronous signal while collecting, *and*
1803 while executing the (relocated) original instruction,
1804 reset the PC to point at the tpoint address, before
1805 reporting to GDB. Otherwise, it's an IPA lib bug: just
1806 report the signal to GDB, and pray for the best. */
1808 lwp
->collecting_fast_tracepoint
= 0;
1811 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1812 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1815 struct regcache
*regcache
;
1817 /* The si_addr on a few signals references the address
1818 of the faulting instruction. Adjust that as
1820 if ((WSTOPSIG (*wstat
) == SIGILL
1821 || WSTOPSIG (*wstat
) == SIGFPE
1822 || WSTOPSIG (*wstat
) == SIGBUS
1823 || WSTOPSIG (*wstat
) == SIGSEGV
)
1824 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
1825 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
1826 /* Final check just to make sure we don't clobber
1827 the siginfo of non-kernel-sent signals. */
1828 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1830 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1831 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
1832 (PTRACE_TYPE_ARG3
) 0, &info
);
1835 regcache
= get_thread_regcache (current_thread
, 1);
1836 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1837 lwp
->stop_pc
= status
.tpoint_addr
;
1839 /* Cancel any fast tracepoint lock this thread was
1841 force_unlock_trace_buffer ();
1844 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1847 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
1848 "stopping all threads momentarily.\n");
1850 stop_all_lwps (1, lwp
);
1852 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1853 lwp
->exit_jump_pad_bkpt
= NULL
;
1855 unstop_all_lwps (1, lwp
);
1857 gdb_assert (lwp
->suspended
>= 0);
1863 debug_printf ("Checking whether LWP %ld needs to move out of the "
1865 lwpid_of (current_thread
));
1867 current_thread
= saved_thread
;
1871 /* Enqueue one signal in the "signals to report later when out of the
1875 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1877 struct pending_signals
*p_sig
;
1878 struct thread_info
*thread
= get_lwp_thread (lwp
);
1881 debug_printf ("Deferring signal %d for LWP %ld.\n",
1882 WSTOPSIG (*wstat
), lwpid_of (thread
));
1886 struct pending_signals
*sig
;
1888 for (sig
= lwp
->pending_signals_to_report
;
1891 debug_printf (" Already queued %d\n",
1894 debug_printf (" (no more currently queued signals)\n");
1897 /* Don't enqueue non-RT signals if they are already in the deferred
1898 queue. (SIGSTOP being the easiest signal to see ending up here
1900 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1902 struct pending_signals
*sig
;
1904 for (sig
= lwp
->pending_signals_to_report
;
1908 if (sig
->signal
== WSTOPSIG (*wstat
))
1911 debug_printf ("Not requeuing already queued non-RT signal %d"
1920 p_sig
= xmalloc (sizeof (*p_sig
));
1921 p_sig
->prev
= lwp
->pending_signals_to_report
;
1922 p_sig
->signal
= WSTOPSIG (*wstat
);
1923 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1924 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1927 lwp
->pending_signals_to_report
= p_sig
;
1930 /* Dequeue one signal from the "signals to report later when out of
1931 the jump pad" list. */
1934 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1936 struct thread_info
*thread
= get_lwp_thread (lwp
);
1938 if (lwp
->pending_signals_to_report
!= NULL
)
1940 struct pending_signals
**p_sig
;
1942 p_sig
= &lwp
->pending_signals_to_report
;
1943 while ((*p_sig
)->prev
!= NULL
)
1944 p_sig
= &(*p_sig
)->prev
;
1946 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1947 if ((*p_sig
)->info
.si_signo
!= 0)
1948 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1954 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
1955 WSTOPSIG (*wstat
), lwpid_of (thread
));
1959 struct pending_signals
*sig
;
1961 for (sig
= lwp
->pending_signals_to_report
;
1964 debug_printf (" Still queued %d\n",
1967 debug_printf (" (no more queued signals)\n");
1976 /* Fetch the possibly triggered data watchpoint info and store it in
1979 On some archs, like x86, that use debug registers to set
1980 watchpoints, it's possible that the way to know which watched
1981 address trapped, is to check the register that is used to select
1982 which address to watch. Problem is, between setting the watchpoint
1983 and reading back which data address trapped, the user may change
1984 the set of watchpoints, and, as a consequence, GDB changes the
1985 debug registers in the inferior. To avoid reading back a stale
1986 stopped-data-address when that happens, we cache in LP the fact
1987 that a watchpoint trapped, and the corresponding data address, as
1988 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
1989 registers meanwhile, we have the cached data we can rely on. */
1992 check_stopped_by_watchpoint (struct lwp_info
*child
)
1994 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
1996 struct thread_info
*saved_thread
;
1998 saved_thread
= current_thread
;
1999 current_thread
= get_lwp_thread (child
);
2001 if (the_low_target
.stopped_by_watchpoint ())
2003 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2005 if (the_low_target
.stopped_data_address
!= NULL
)
2006 child
->stopped_data_address
2007 = the_low_target
.stopped_data_address ();
2009 child
->stopped_data_address
= 0;
2012 current_thread
= saved_thread
;
2015 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2018 /* Return the ptrace options that we want to try to enable. */
2021 linux_low_ptrace_options (int attached
)
2026 options
|= PTRACE_O_EXITKILL
;
2028 if (report_fork_events
)
2029 options
|= PTRACE_O_TRACEFORK
;
2031 if (report_vfork_events
)
2032 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2037 /* Do low-level handling of the event, and check if we should go on
2038 and pass it to caller code. Return the affected lwp if we are, or
2041 static struct lwp_info
*
2042 linux_low_filter_event (int lwpid
, int wstat
)
2044 struct lwp_info
*child
;
2045 struct thread_info
*thread
;
2046 int have_stop_pc
= 0;
2048 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2050 /* If we didn't find a process, one of two things presumably happened:
2051 - A process we started and then detached from has exited. Ignore it.
2052 - A process we are controlling has forked and the new child's stop
2053 was reported to us by the kernel. Save its PID. */
2054 if (child
== NULL
&& WIFSTOPPED (wstat
))
2056 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2059 else if (child
== NULL
)
2062 thread
= get_lwp_thread (child
);
2066 child
->last_status
= wstat
;
2068 /* Check if the thread has exited. */
2069 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2072 debug_printf ("LLFE: %d exited.\n", lwpid
);
2073 if (num_lwps (pid_of (thread
)) > 1)
2076 /* If there is at least one more LWP, then the exit signal was
2077 not the end of the debugged application and should be
2084 /* This was the last lwp in the process. Since events are
2085 serialized to GDB core, and we can't report this one
2086 right now, but GDB core and the other target layers will
2087 want to be notified about the exit code/signal, leave the
2088 status pending for the next time we're able to report
2090 mark_lwp_dead (child
, wstat
);
2095 gdb_assert (WIFSTOPPED (wstat
));
2097 if (WIFSTOPPED (wstat
))
2099 struct process_info
*proc
;
2101 /* Architecture-specific setup after inferior is running. This
2102 needs to happen after we have attached to the inferior and it
2103 is stopped for the first time, but before we access any
2104 inferior registers. */
2105 proc
= find_process_pid (pid_of (thread
));
2106 if (proc
->priv
->new_inferior
)
2108 struct thread_info
*saved_thread
;
2110 saved_thread
= current_thread
;
2111 current_thread
= thread
;
2113 the_low_target
.arch_setup ();
2115 current_thread
= saved_thread
;
2117 proc
->priv
->new_inferior
= 0;
2121 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2123 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2124 int options
= linux_low_ptrace_options (proc
->attached
);
2126 linux_enable_event_reporting (lwpid
, options
);
2127 child
->must_set_ptrace_flags
= 0;
2130 /* Be careful to not overwrite stop_pc until
2131 check_stopped_by_breakpoint is called. */
2132 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2133 && linux_is_extended_waitstatus (wstat
))
2135 child
->stop_pc
= get_pc (child
);
2136 if (handle_extended_wait (child
, wstat
))
2138 /* The event has been handled, so just return without
2144 /* Check first whether this was a SW/HW breakpoint before checking
2145 watchpoints, because at least s390 can't tell the data address of
2146 hardware watchpoint hits, and returns stopped-by-watchpoint as
2147 long as there's a watchpoint set. */
2148 if (WIFSTOPPED (wstat
) && linux_wstatus_maybe_breakpoint (wstat
))
2150 if (check_stopped_by_breakpoint (child
))
2154 /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint
2155 or hardware watchpoint. Check which is which if we got
2156 TARGET_STOPPED_BY_HW_BREAKPOINT. */
2157 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2158 && (child
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
2159 || child
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
2160 check_stopped_by_watchpoint (child
);
2163 child
->stop_pc
= get_pc (child
);
2165 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2166 && child
->stop_expected
)
2169 debug_printf ("Expected stop.\n");
2170 child
->stop_expected
= 0;
2172 if (thread
->last_resume_kind
== resume_stop
)
2174 /* We want to report the stop to the core. Treat the
2175 SIGSTOP as a normal event. */
2177 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2178 target_pid_to_str (ptid_of (thread
)));
2180 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2182 /* Stopping threads. We don't want this SIGSTOP to end up
2185 debug_printf ("LLW: SIGSTOP caught for %s "
2186 "while stopping threads.\n",
2187 target_pid_to_str (ptid_of (thread
)));
2192 /* This is a delayed SIGSTOP. Filter out the event. */
2194 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2195 child
->stepping
? "step" : "continue",
2196 target_pid_to_str (ptid_of (thread
)));
2198 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2203 child
->status_pending_p
= 1;
2204 child
->status_pending
= wstat
;
2208 /* Resume LWPs that are currently stopped without any pending status
2209 to report, but are resumed from the core's perspective. */
2212 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2214 struct thread_info
*thread
= (struct thread_info
*) entry
;
2215 struct lwp_info
*lp
= get_thread_lwp (thread
);
2218 && !lp
->status_pending_p
2219 && thread
->last_resume_kind
!= resume_stop
2220 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2222 int step
= thread
->last_resume_kind
== resume_step
;
2225 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2226 target_pid_to_str (ptid_of (thread
)),
2227 paddress (lp
->stop_pc
),
2230 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2234 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2235 match FILTER_PTID (leaving others pending). The PTIDs can be:
2236 minus_one_ptid, to specify any child; a pid PTID, specifying all
2237 lwps of a thread group; or a PTID representing a single lwp. Store
2238 the stop status through the status pointer WSTAT. OPTIONS is
2239 passed to the waitpid call. Return 0 if no event was found and
2240 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2241 was found. Return the PID of the stopped child otherwise. */
2244 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2245 int *wstatp
, int options
)
2247 struct thread_info
*event_thread
;
2248 struct lwp_info
*event_child
, *requested_child
;
2249 sigset_t block_mask
, prev_mask
;
2252 /* N.B. event_thread points to the thread_info struct that contains
2253 event_child. Keep them in sync. */
2254 event_thread
= NULL
;
2256 requested_child
= NULL
;
2258 /* Check for a lwp with a pending status. */
2260 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2262 event_thread
= (struct thread_info
*)
2263 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2264 if (event_thread
!= NULL
)
2265 event_child
= get_thread_lwp (event_thread
);
2266 if (debug_threads
&& event_thread
)
2267 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2269 else if (!ptid_equal (filter_ptid
, null_ptid
))
2271 requested_child
= find_lwp_pid (filter_ptid
);
2273 if (stopping_threads
== NOT_STOPPING_THREADS
2274 && requested_child
->status_pending_p
2275 && requested_child
->collecting_fast_tracepoint
)
2277 enqueue_one_deferred_signal (requested_child
,
2278 &requested_child
->status_pending
);
2279 requested_child
->status_pending_p
= 0;
2280 requested_child
->status_pending
= 0;
2281 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2284 if (requested_child
->suspended
2285 && requested_child
->status_pending_p
)
2287 internal_error (__FILE__
, __LINE__
,
2288 "requesting an event out of a"
2289 " suspended child?");
2292 if (requested_child
->status_pending_p
)
2294 event_child
= requested_child
;
2295 event_thread
= get_lwp_thread (event_child
);
2299 if (event_child
!= NULL
)
2302 debug_printf ("Got an event from pending child %ld (%04x)\n",
2303 lwpid_of (event_thread
), event_child
->status_pending
);
2304 *wstatp
= event_child
->status_pending
;
2305 event_child
->status_pending_p
= 0;
2306 event_child
->status_pending
= 0;
2307 current_thread
= event_thread
;
2308 return lwpid_of (event_thread
);
2311 /* But if we don't find a pending event, we'll have to wait.
2313 We only enter this loop if no process has a pending wait status.
2314 Thus any action taken in response to a wait status inside this
2315 loop is responding as soon as we detect the status, not after any
2318 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2319 all signals while here. */
2320 sigfillset (&block_mask
);
2321 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2323 /* Always pull all events out of the kernel. We'll randomly select
2324 an event LWP out of all that have events, to prevent
2326 while (event_child
== NULL
)
2330 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2333 - If the thread group leader exits while other threads in the
2334 thread group still exist, waitpid(TGID, ...) hangs. That
2335 waitpid won't return an exit status until the other threads
2336 in the group are reaped.
2338 - When a non-leader thread execs, that thread just vanishes
2339 without reporting an exit (so we'd hang if we waited for it
2340 explicitly in that case). The exec event is reported to
2341 the TGID pid (although we don't currently enable exec
2344 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2347 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2348 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2354 debug_printf ("LLW: waitpid %ld received %s\n",
2355 (long) ret
, status_to_str (*wstatp
));
2358 /* Filter all events. IOW, leave all events pending. We'll
2359 randomly select an event LWP out of all that have events
2361 linux_low_filter_event (ret
, *wstatp
);
2362 /* Retry until nothing comes out of waitpid. A single
2363 SIGCHLD can indicate more than one child stopped. */
2367 /* Now that we've pulled all events out of the kernel, resume
2368 LWPs that don't have an interesting event to report. */
2369 if (stopping_threads
== NOT_STOPPING_THREADS
)
2370 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2372 /* ... and find an LWP with a status to report to the core, if
2374 event_thread
= (struct thread_info
*)
2375 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2376 if (event_thread
!= NULL
)
2378 event_child
= get_thread_lwp (event_thread
);
2379 *wstatp
= event_child
->status_pending
;
2380 event_child
->status_pending_p
= 0;
2381 event_child
->status_pending
= 0;
2385 /* Check for zombie thread group leaders. Those can't be reaped
2386 until all other threads in the thread group are. */
2387 check_zombie_leaders ();
2389 /* If there are no resumed children left in the set of LWPs we
2390 want to wait for, bail. We can't just block in
2391 waitpid/sigsuspend, because lwps might have been left stopped
2392 in trace-stop state, and we'd be stuck forever waiting for
2393 their status to change (which would only happen if we resumed
2394 them). Even if WNOHANG is set, this return code is preferred
2395 over 0 (below), as it is more detailed. */
2396 if ((find_inferior (&all_threads
,
2397 not_stopped_callback
,
2398 &wait_ptid
) == NULL
))
2401 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2402 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2406 /* No interesting event to report to the caller. */
2407 if ((options
& WNOHANG
))
2410 debug_printf ("WNOHANG set, no event found\n");
2412 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2416 /* Block until we get an event reported with SIGCHLD. */
2418 debug_printf ("sigsuspend'ing\n");
2420 sigsuspend (&prev_mask
);
2421 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2425 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2427 current_thread
= event_thread
;
2429 /* Check for thread exit. */
2430 if (! WIFSTOPPED (*wstatp
))
2432 gdb_assert (last_thread_of_process_p (pid_of (event_thread
)));
2435 debug_printf ("LWP %d is the last lwp of process. "
2436 "Process %ld exiting.\n",
2437 pid_of (event_thread
), lwpid_of (event_thread
));
2438 return lwpid_of (event_thread
);
2441 return lwpid_of (event_thread
);
2444 /* Wait for an event from child(ren) PTID. PTIDs can be:
2445 minus_one_ptid, to specify any child; a pid PTID, specifying all
2446 lwps of a thread group; or a PTID representing a single lwp. Store
2447 the stop status through the status pointer WSTAT. OPTIONS is
2448 passed to the waitpid call. Return 0 if no event was found and
2449 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2450 was found. Return the PID of the stopped child otherwise. */
2453 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2455 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2458 /* Count the LWP's that have had events. */
2461 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2463 struct thread_info
*thread
= (struct thread_info
*) entry
;
2464 struct lwp_info
*lp
= get_thread_lwp (thread
);
2467 gdb_assert (count
!= NULL
);
2469 /* Count only resumed LWPs that have an event pending. */
2470 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2471 && lp
->status_pending_p
)
2477 /* Select the LWP (if any) that is currently being single-stepped. */
2480 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2482 struct thread_info
*thread
= (struct thread_info
*) entry
;
2483 struct lwp_info
*lp
= get_thread_lwp (thread
);
2485 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2486 && thread
->last_resume_kind
== resume_step
2487 && lp
->status_pending_p
)
2493 /* Select the Nth LWP that has had an event. */
2496 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2498 struct thread_info
*thread
= (struct thread_info
*) entry
;
2499 struct lwp_info
*lp
= get_thread_lwp (thread
);
2500 int *selector
= data
;
2502 gdb_assert (selector
!= NULL
);
2504 /* Select only resumed LWPs that have an event pending. */
2505 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2506 && lp
->status_pending_p
)
2507 if ((*selector
)-- == 0)
2513 /* Select one LWP out of those that have events pending. */
2516 select_event_lwp (struct lwp_info
**orig_lp
)
2519 int random_selector
;
2520 struct thread_info
*event_thread
= NULL
;
2522 /* In all-stop, give preference to the LWP that is being
2523 single-stepped. There will be at most one, and it's the LWP that
2524 the core is most interested in. If we didn't do this, then we'd
2525 have to handle pending step SIGTRAPs somehow in case the core
2526 later continues the previously-stepped thread, otherwise we'd
2527 report the pending SIGTRAP, and the core, not having stepped the
2528 thread, wouldn't understand what the trap was for, and therefore
2529 would report it to the user as a random signal. */
2533 = (struct thread_info
*) find_inferior (&all_threads
,
2534 select_singlestep_lwp_callback
,
2536 if (event_thread
!= NULL
)
2539 debug_printf ("SEL: Select single-step %s\n",
2540 target_pid_to_str (ptid_of (event_thread
)));
2543 if (event_thread
== NULL
)
2545 /* No single-stepping LWP. Select one at random, out of those
2546 which have had events. */
2548 /* First see how many events we have. */
2549 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2550 gdb_assert (num_events
> 0);
2552 /* Now randomly pick a LWP out of those that have had
2554 random_selector
= (int)
2555 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2557 if (debug_threads
&& num_events
> 1)
2558 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2559 num_events
, random_selector
);
2562 = (struct thread_info
*) find_inferior (&all_threads
,
2563 select_event_lwp_callback
,
2567 if (event_thread
!= NULL
)
2569 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2571 /* Switch the event LWP. */
2572 *orig_lp
= event_lp
;
2576 /* Decrement the suspend count of an LWP. */
2579 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2581 struct thread_info
*thread
= (struct thread_info
*) entry
;
2582 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2584 /* Ignore EXCEPT. */
2590 gdb_assert (lwp
->suspended
>= 0);
2594 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2598 unsuspend_all_lwps (struct lwp_info
*except
)
2600 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2603 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2604 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2606 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2607 static ptid_t
linux_wait_1 (ptid_t ptid
,
2608 struct target_waitstatus
*ourstatus
,
2609 int target_options
);
2611 /* Stabilize threads (move out of jump pads).
2613 If a thread is midway collecting a fast tracepoint, we need to
2614 finish the collection and move it out of the jump pad before
2615 reporting the signal.
2617 This avoids recursion while collecting (when a signal arrives
2618 midway, and the signal handler itself collects), which would trash
2619 the trace buffer. In case the user set a breakpoint in a signal
2620 handler, this avoids the backtrace showing the jump pad, etc..
2621 Most importantly, there are certain things we can't do safely if
2622 threads are stopped in a jump pad (or in its callee's). For
2625 - starting a new trace run. A thread still collecting the
2626 previous run, could trash the trace buffer when resumed. The trace
2627 buffer control structures would have been reset but the thread had
2628 no way to tell. The thread could even midway memcpy'ing to the
2629 buffer, which would mean that when resumed, it would clobber the
2630 trace buffer that had been set for a new run.
2632 - we can't rewrite/reuse the jump pads for new tracepoints
2633 safely. Say you do tstart while a thread is stopped midway while
2634 collecting. When the thread is later resumed, it finishes the
2635 collection, and returns to the jump pad, to execute the original
2636 instruction that was under the tracepoint jump at the time the
2637 older run had been started. If the jump pad had been rewritten
2638 since for something else in the new run, the thread would now
2639 execute the wrong / random instructions. */
2642 linux_stabilize_threads (void)
2644 struct thread_info
*saved_thread
;
2645 struct thread_info
*thread_stuck
;
2648 = (struct thread_info
*) find_inferior (&all_threads
,
2649 stuck_in_jump_pad_callback
,
2651 if (thread_stuck
!= NULL
)
2654 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2655 lwpid_of (thread_stuck
));
2659 saved_thread
= current_thread
;
2661 stabilizing_threads
= 1;
2664 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2666 /* Loop until all are stopped out of the jump pads. */
2667 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2669 struct target_waitstatus ourstatus
;
2670 struct lwp_info
*lwp
;
2673 /* Note that we go through the full wait even loop. While
2674 moving threads out of jump pad, we need to be able to step
2675 over internal breakpoints and such. */
2676 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2678 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2680 lwp
= get_thread_lwp (current_thread
);
2685 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2686 || current_thread
->last_resume_kind
== resume_stop
)
2688 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2689 enqueue_one_deferred_signal (lwp
, &wstat
);
2694 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2696 stabilizing_threads
= 0;
2698 current_thread
= saved_thread
;
2703 = (struct thread_info
*) find_inferior (&all_threads
,
2704 stuck_in_jump_pad_callback
,
2706 if (thread_stuck
!= NULL
)
2707 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2708 lwpid_of (thread_stuck
));
2712 static void async_file_mark (void);
2714 /* Convenience function that is called when the kernel reports an
2715 event that is not passed out to GDB. */
2718 ignore_event (struct target_waitstatus
*ourstatus
)
2720 /* If we got an event, there may still be others, as a single
2721 SIGCHLD can indicate more than one child stopped. This forces
2722 another target_wait call. */
2725 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2729 /* Return non-zero if WAITSTATUS reflects an extended linux
2730 event. Otherwise, return zero. */
2733 extended_event_reported (const struct target_waitstatus
*waitstatus
)
2735 if (waitstatus
== NULL
)
2738 return (waitstatus
->kind
== TARGET_WAITKIND_FORKED
2739 || waitstatus
->kind
== TARGET_WAITKIND_VFORKED
2740 || waitstatus
->kind
== TARGET_WAITKIND_VFORK_DONE
);
2743 /* Wait for process, returns status. */
2746 linux_wait_1 (ptid_t ptid
,
2747 struct target_waitstatus
*ourstatus
, int target_options
)
2750 struct lwp_info
*event_child
;
2753 int step_over_finished
;
2754 int bp_explains_trap
;
2755 int maybe_internal_trap
;
2763 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
2766 /* Translate generic target options into linux options. */
2768 if (target_options
& TARGET_WNOHANG
)
2771 bp_explains_trap
= 0;
2774 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2776 if (ptid_equal (step_over_bkpt
, null_ptid
))
2777 pid
= linux_wait_for_event (ptid
, &w
, options
);
2781 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2782 target_pid_to_str (step_over_bkpt
));
2783 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2788 gdb_assert (target_options
& TARGET_WNOHANG
);
2792 debug_printf ("linux_wait_1 ret = null_ptid, "
2793 "TARGET_WAITKIND_IGNORE\n");
2797 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2804 debug_printf ("linux_wait_1 ret = null_ptid, "
2805 "TARGET_WAITKIND_NO_RESUMED\n");
2809 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
2813 event_child
= get_thread_lwp (current_thread
);
2815 /* linux_wait_for_event only returns an exit status for the last
2816 child of a process. Report it. */
2817 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2821 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2822 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2826 debug_printf ("linux_wait_1 ret = %s, exited with "
2828 target_pid_to_str (ptid_of (current_thread
)),
2835 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2836 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
2840 debug_printf ("linux_wait_1 ret = %s, terminated with "
2842 target_pid_to_str (ptid_of (current_thread
)),
2848 return ptid_of (current_thread
);
2851 /* If step-over executes a breakpoint instruction, it means a
2852 gdb/gdbserver breakpoint had been planted on top of a permanent
2853 breakpoint. The PC has been adjusted by
2854 check_stopped_by_breakpoint to point at the breakpoint address.
2855 Advance the PC manually past the breakpoint, otherwise the
2856 program would keep trapping the permanent breakpoint forever. */
2857 if (!ptid_equal (step_over_bkpt
, null_ptid
)
2858 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
2860 unsigned int increment_pc
= the_low_target
.breakpoint_len
;
2864 debug_printf ("step-over for %s executed software breakpoint\n",
2865 target_pid_to_str (ptid_of (current_thread
)));
2868 if (increment_pc
!= 0)
2870 struct regcache
*regcache
2871 = get_thread_regcache (current_thread
, 1);
2873 event_child
->stop_pc
+= increment_pc
;
2874 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2876 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
2877 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2881 /* If this event was not handled before, and is not a SIGTRAP, we
2882 report it. SIGILL and SIGSEGV are also treated as traps in case
2883 a breakpoint is inserted at the current PC. If this target does
2884 not support internal breakpoints at all, we also report the
2885 SIGTRAP without further processing; it's of no concern to us. */
2887 = (supports_breakpoints ()
2888 && (WSTOPSIG (w
) == SIGTRAP
2889 || ((WSTOPSIG (w
) == SIGILL
2890 || WSTOPSIG (w
) == SIGSEGV
)
2891 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2893 if (maybe_internal_trap
)
2895 /* Handle anything that requires bookkeeping before deciding to
2896 report the event or continue waiting. */
2898 /* First check if we can explain the SIGTRAP with an internal
2899 breakpoint, or if we should possibly report the event to GDB.
2900 Do this before anything that may remove or insert a
2902 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2904 /* We have a SIGTRAP, possibly a step-over dance has just
2905 finished. If so, tweak the state machine accordingly,
2906 reinsert breakpoints and delete any reinsert (software
2907 single-step) breakpoints. */
2908 step_over_finished
= finish_step_over (event_child
);
2910 /* Now invoke the callbacks of any internal breakpoints there. */
2911 check_breakpoints (event_child
->stop_pc
);
2913 /* Handle tracepoint data collecting. This may overflow the
2914 trace buffer, and cause a tracing stop, removing
2916 trace_event
= handle_tracepoints (event_child
);
2918 if (bp_explains_trap
)
2920 /* If we stepped or ran into an internal breakpoint, we've
2921 already handled it. So next time we resume (from this
2922 PC), we should step over it. */
2924 debug_printf ("Hit a gdbserver breakpoint.\n");
2926 if (breakpoint_here (event_child
->stop_pc
))
2927 event_child
->need_step_over
= 1;
2932 /* We have some other signal, possibly a step-over dance was in
2933 progress, and it should be cancelled too. */
2934 step_over_finished
= finish_step_over (event_child
);
2937 /* We have all the data we need. Either report the event to GDB, or
2938 resume threads and keep waiting for more. */
2940 /* If we're collecting a fast tracepoint, finish the collection and
2941 move out of the jump pad before delivering a signal. See
2942 linux_stabilize_threads. */
2945 && WSTOPSIG (w
) != SIGTRAP
2946 && supports_fast_tracepoints ()
2947 && agent_loaded_p ())
2950 debug_printf ("Got signal %d for LWP %ld. Check if we need "
2951 "to defer or adjust it.\n",
2952 WSTOPSIG (w
), lwpid_of (current_thread
));
2954 /* Allow debugging the jump pad itself. */
2955 if (current_thread
->last_resume_kind
!= resume_step
2956 && maybe_move_out_of_jump_pad (event_child
, &w
))
2958 enqueue_one_deferred_signal (event_child
, &w
);
2961 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
2962 WSTOPSIG (w
), lwpid_of (current_thread
));
2964 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2966 return ignore_event (ourstatus
);
2970 if (event_child
->collecting_fast_tracepoint
)
2973 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
2974 "Check if we're already there.\n",
2975 lwpid_of (current_thread
),
2976 event_child
->collecting_fast_tracepoint
);
2980 event_child
->collecting_fast_tracepoint
2981 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2983 if (event_child
->collecting_fast_tracepoint
!= 1)
2985 /* No longer need this breakpoint. */
2986 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2989 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
2990 "stopping all threads momentarily.\n");
2992 /* Other running threads could hit this breakpoint.
2993 We don't handle moribund locations like GDB does,
2994 instead we always pause all threads when removing
2995 breakpoints, so that any step-over or
2996 decr_pc_after_break adjustment is always taken
2997 care of while the breakpoint is still
2999 stop_all_lwps (1, event_child
);
3001 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3002 event_child
->exit_jump_pad_bkpt
= NULL
;
3004 unstop_all_lwps (1, event_child
);
3006 gdb_assert (event_child
->suspended
>= 0);
3010 if (event_child
->collecting_fast_tracepoint
== 0)
3013 debug_printf ("fast tracepoint finished "
3014 "collecting successfully.\n");
3016 /* We may have a deferred signal to report. */
3017 if (dequeue_one_deferred_signal (event_child
, &w
))
3020 debug_printf ("dequeued one signal.\n");
3025 debug_printf ("no deferred signals.\n");
3027 if (stabilizing_threads
)
3029 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3030 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3034 debug_printf ("linux_wait_1 ret = %s, stopped "
3035 "while stabilizing threads\n",
3036 target_pid_to_str (ptid_of (current_thread
)));
3040 return ptid_of (current_thread
);
3046 /* Check whether GDB would be interested in this event. */
3048 /* If GDB is not interested in this signal, don't stop other
3049 threads, and don't report it to GDB. Just resume the inferior
3050 right away. We do this for threading-related signals as well as
3051 any that GDB specifically requested we ignore. But never ignore
3052 SIGSTOP if we sent it ourselves, and do not ignore signals when
3053 stepping - they may require special handling to skip the signal
3054 handler. Also never ignore signals that could be caused by a
3056 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
3059 && current_thread
->last_resume_kind
!= resume_step
3061 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3062 (current_process ()->priv
->thread_db
!= NULL
3063 && (WSTOPSIG (w
) == __SIGRTMIN
3064 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3067 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3068 && !(WSTOPSIG (w
) == SIGSTOP
3069 && current_thread
->last_resume_kind
== resume_stop
)
3070 && !linux_wstatus_maybe_breakpoint (w
))))
3072 siginfo_t info
, *info_p
;
3075 debug_printf ("Ignored signal %d for LWP %ld.\n",
3076 WSTOPSIG (w
), lwpid_of (current_thread
));
3078 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3079 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3083 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3084 WSTOPSIG (w
), info_p
);
3085 return ignore_event (ourstatus
);
3088 /* Note that all addresses are always "out of the step range" when
3089 there's no range to begin with. */
3090 in_step_range
= lwp_in_step_range (event_child
);
3092 /* If GDB wanted this thread to single step, and the thread is out
3093 of the step range, we always want to report the SIGTRAP, and let
3094 GDB handle it. Watchpoints should always be reported. So should
3095 signals we can't explain. A SIGTRAP we can't explain could be a
3096 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3097 do, we're be able to handle GDB breakpoints on top of internal
3098 breakpoints, by handling the internal breakpoint and still
3099 reporting the event to GDB. If we don't, we're out of luck, GDB
3100 won't see the breakpoint hit. */
3101 report_to_gdb
= (!maybe_internal_trap
3102 || (current_thread
->last_resume_kind
== resume_step
3104 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3105 || (!step_over_finished
&& !in_step_range
3106 && !bp_explains_trap
&& !trace_event
)
3107 || (gdb_breakpoint_here (event_child
->stop_pc
)
3108 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3109 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3110 || extended_event_reported (&event_child
->waitstatus
));
3112 run_breakpoint_commands (event_child
->stop_pc
);
3114 /* We found no reason GDB would want us to stop. We either hit one
3115 of our own breakpoints, or finished an internal step GDB
3116 shouldn't know about. */
3121 if (bp_explains_trap
)
3122 debug_printf ("Hit a gdbserver breakpoint.\n");
3123 if (step_over_finished
)
3124 debug_printf ("Step-over finished.\n");
3126 debug_printf ("Tracepoint event.\n");
3127 if (lwp_in_step_range (event_child
))
3128 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3129 paddress (event_child
->stop_pc
),
3130 paddress (event_child
->step_range_start
),
3131 paddress (event_child
->step_range_end
));
3132 if (extended_event_reported (&event_child
->waitstatus
))
3134 char *str
= target_waitstatus_to_string (ourstatus
);
3135 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3136 lwpid_of (get_lwp_thread (event_child
)), str
);
3141 /* We're not reporting this breakpoint to GDB, so apply the
3142 decr_pc_after_break adjustment to the inferior's regcache
3145 if (the_low_target
.set_pc
!= NULL
)
3147 struct regcache
*regcache
3148 = get_thread_regcache (current_thread
, 1);
3149 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3152 /* We may have finished stepping over a breakpoint. If so,
3153 we've stopped and suspended all LWPs momentarily except the
3154 stepping one. This is where we resume them all again. We're
3155 going to keep waiting, so use proceed, which handles stepping
3156 over the next breakpoint. */
3158 debug_printf ("proceeding all threads.\n");
3160 if (step_over_finished
)
3161 unsuspend_all_lwps (event_child
);
3163 proceed_all_lwps ();
3164 return ignore_event (ourstatus
);
3169 if (current_thread
->last_resume_kind
== resume_step
)
3171 if (event_child
->step_range_start
== event_child
->step_range_end
)
3172 debug_printf ("GDB wanted to single-step, reporting event.\n");
3173 else if (!lwp_in_step_range (event_child
))
3174 debug_printf ("Out of step range, reporting event.\n");
3176 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3177 debug_printf ("Stopped by watchpoint.\n");
3178 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3179 debug_printf ("Stopped by GDB breakpoint.\n");
3181 debug_printf ("Hit a non-gdbserver trap event.\n");
3184 /* Alright, we're going to report a stop. */
3186 if (!stabilizing_threads
)
3188 /* In all-stop, stop all threads. */
3190 stop_all_lwps (0, NULL
);
3192 /* If we're not waiting for a specific LWP, choose an event LWP
3193 from among those that have had events. Giving equal priority
3194 to all LWPs that have had events helps prevent
3196 if (ptid_equal (ptid
, minus_one_ptid
))
3198 event_child
->status_pending_p
= 1;
3199 event_child
->status_pending
= w
;
3201 select_event_lwp (&event_child
);
3203 /* current_thread and event_child must stay in sync. */
3204 current_thread
= get_lwp_thread (event_child
);
3206 event_child
->status_pending_p
= 0;
3207 w
= event_child
->status_pending
;
3210 if (step_over_finished
)
3214 /* If we were doing a step-over, all other threads but
3215 the stepping one had been paused in start_step_over,
3216 with their suspend counts incremented. We don't want
3217 to do a full unstop/unpause, because we're in
3218 all-stop mode (so we want threads stopped), but we
3219 still need to unsuspend the other threads, to
3220 decrement their `suspended' count back. */
3221 unsuspend_all_lwps (event_child
);
3225 /* If we just finished a step-over, then all threads had
3226 been momentarily paused. In all-stop, that's fine,
3227 we want threads stopped by now anyway. In non-stop,
3228 we need to re-resume threads that GDB wanted to be
3230 unstop_all_lwps (1, event_child
);
3234 /* Stabilize threads (move out of jump pads). */
3236 stabilize_threads ();
3240 /* If we just finished a step-over, then all threads had been
3241 momentarily paused. In all-stop, that's fine, we want
3242 threads stopped by now anyway. In non-stop, we need to
3243 re-resume threads that GDB wanted to be running. */
3244 if (step_over_finished
)
3245 unstop_all_lwps (1, event_child
);
3248 if (extended_event_reported (&event_child
->waitstatus
))
3250 /* If the reported event is a fork, vfork or exec, let GDB know. */
3251 ourstatus
->kind
= event_child
->waitstatus
.kind
;
3252 ourstatus
->value
= event_child
->waitstatus
.value
;
3254 /* Clear the event lwp's waitstatus since we handled it already. */
3255 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3258 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3260 /* Now that we've selected our final event LWP, un-adjust its PC if
3261 it was a software breakpoint, and the client doesn't know we can
3262 adjust the breakpoint ourselves. */
3263 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3264 && !swbreak_feature
)
3266 int decr_pc
= the_low_target
.decr_pc_after_break
;
3270 struct regcache
*regcache
3271 = get_thread_regcache (current_thread
, 1);
3272 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3276 if (current_thread
->last_resume_kind
== resume_stop
3277 && WSTOPSIG (w
) == SIGSTOP
)
3279 /* A thread that has been requested to stop by GDB with vCont;t,
3280 and it stopped cleanly, so report as SIG0. The use of
3281 SIGSTOP is an implementation detail. */
3282 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3284 else if (current_thread
->last_resume_kind
== resume_stop
3285 && WSTOPSIG (w
) != SIGSTOP
)
3287 /* A thread that has been requested to stop by GDB with vCont;t,
3288 but, it stopped for other reasons. */
3289 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3291 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3293 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3296 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3300 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3301 target_pid_to_str (ptid_of (current_thread
)),
3302 ourstatus
->kind
, ourstatus
->value
.sig
);
3306 return ptid_of (current_thread
);
3309 /* Get rid of any pending event in the pipe. */
3311 async_file_flush (void)
3317 ret
= read (linux_event_pipe
[0], &buf
, 1);
3318 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3321 /* Put something in the pipe, so the event loop wakes up. */
3323 async_file_mark (void)
3327 async_file_flush ();
3330 ret
= write (linux_event_pipe
[1], "+", 1);
3331 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3333 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3334 be awakened anyway. */
3338 linux_wait (ptid_t ptid
,
3339 struct target_waitstatus
*ourstatus
, int target_options
)
3343 /* Flush the async file first. */
3344 if (target_is_async_p ())
3345 async_file_flush ();
3349 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3351 while ((target_options
& TARGET_WNOHANG
) == 0
3352 && ptid_equal (event_ptid
, null_ptid
)
3353 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3355 /* If at least one stop was reported, there may be more. A single
3356 SIGCHLD can signal more than one child stop. */
3357 if (target_is_async_p ()
3358 && (target_options
& TARGET_WNOHANG
) != 0
3359 && !ptid_equal (event_ptid
, null_ptid
))
3365 /* Send a signal to an LWP. */
3368 kill_lwp (unsigned long lwpid
, int signo
)
3370 /* Use tkill, if possible, in case we are using nptl threads. If tkill
3371 fails, then we are not using nptl threads and we should be using kill. */
3375 static int tkill_failed
;
3382 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3383 if (errno
!= ENOSYS
)
3390 return kill (lwpid
, signo
);
3394 linux_stop_lwp (struct lwp_info
*lwp
)
3400 send_sigstop (struct lwp_info
*lwp
)
3404 pid
= lwpid_of (get_lwp_thread (lwp
));
3406 /* If we already have a pending stop signal for this process, don't
3408 if (lwp
->stop_expected
)
3411 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3417 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3419 lwp
->stop_expected
= 1;
3420 kill_lwp (pid
, SIGSTOP
);
3424 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3426 struct thread_info
*thread
= (struct thread_info
*) entry
;
3427 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3429 /* Ignore EXCEPT. */
3440 /* Increment the suspend count of an LWP, and stop it, if not stopped
3443 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3446 struct thread_info
*thread
= (struct thread_info
*) entry
;
3447 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3449 /* Ignore EXCEPT. */
3455 return send_sigstop_callback (entry
, except
);
3459 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3461 /* It's dead, really. */
3464 /* Store the exit status for later. */
3465 lwp
->status_pending_p
= 1;
3466 lwp
->status_pending
= wstat
;
3468 /* Prevent trying to stop it. */
3471 /* No further stops are expected from a dead lwp. */
3472 lwp
->stop_expected
= 0;
3475 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3478 wait_for_sigstop (void)
3480 struct thread_info
*saved_thread
;
3485 saved_thread
= current_thread
;
3486 if (saved_thread
!= NULL
)
3487 saved_tid
= saved_thread
->entry
.id
;
3489 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3492 debug_printf ("wait_for_sigstop: pulling events\n");
3494 /* Passing NULL_PTID as filter indicates we want all events to be
3495 left pending. Eventually this returns when there are no
3496 unwaited-for children left. */
3497 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3499 gdb_assert (ret
== -1);
3501 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3502 current_thread
= saved_thread
;
3506 debug_printf ("Previously current thread died.\n");
3510 /* We can't change the current inferior behind GDB's back,
3511 otherwise, a subsequent command may apply to the wrong
3513 current_thread
= NULL
;
3517 /* Set a valid thread as current. */
3518 set_desired_thread (0);
3523 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3524 move it out, because we need to report the stop event to GDB. For
3525 example, if the user puts a breakpoint in the jump pad, it's
3526 because she wants to debug it. */
3529 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3531 struct thread_info
*thread
= (struct thread_info
*) entry
;
3532 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3534 gdb_assert (lwp
->suspended
== 0);
3535 gdb_assert (lwp
->stopped
);
3537 /* Allow debugging the jump pad, gdb_collect, etc.. */
3538 return (supports_fast_tracepoints ()
3539 && agent_loaded_p ()
3540 && (gdb_breakpoint_here (lwp
->stop_pc
)
3541 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3542 || thread
->last_resume_kind
== resume_step
)
3543 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3547 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3549 struct thread_info
*thread
= (struct thread_info
*) entry
;
3550 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3553 gdb_assert (lwp
->suspended
== 0);
3554 gdb_assert (lwp
->stopped
);
3556 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3558 /* Allow debugging the jump pad, gdb_collect, etc. */
3559 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3560 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3561 && thread
->last_resume_kind
!= resume_step
3562 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3565 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3570 lwp
->status_pending_p
= 0;
3571 enqueue_one_deferred_signal (lwp
, wstat
);
3574 debug_printf ("Signal %d for LWP %ld deferred "
3576 WSTOPSIG (*wstat
), lwpid_of (thread
));
3579 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3586 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3588 struct thread_info
*thread
= (struct thread_info
*) entry
;
3589 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3598 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3599 If SUSPEND, then also increase the suspend count of every LWP,
3603 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3605 /* Should not be called recursively. */
3606 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3611 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3612 suspend
? "stop-and-suspend" : "stop",
3614 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3618 stopping_threads
= (suspend
3619 ? STOPPING_AND_SUSPENDING_THREADS
3620 : STOPPING_THREADS
);
3623 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
3625 find_inferior (&all_threads
, send_sigstop_callback
, except
);
3626 wait_for_sigstop ();
3627 stopping_threads
= NOT_STOPPING_THREADS
;
3631 debug_printf ("stop_all_lwps done, setting stopping_threads "
3632 "back to !stopping\n");
3637 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
3638 SIGNAL is nonzero, give it that signal. */
3641 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
3642 int step
, int signal
, siginfo_t
*info
)
3644 struct thread_info
*thread
= get_lwp_thread (lwp
);
3645 struct thread_info
*saved_thread
;
3646 int fast_tp_collecting
;
3648 if (lwp
->stopped
== 0)
3651 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3653 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3655 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3656 user used the "jump" command, or "set $pc = foo"). */
3657 if (lwp
->stop_pc
!= get_pc (lwp
))
3659 /* Collecting 'while-stepping' actions doesn't make sense
3661 release_while_stepping_state_list (thread
);
3664 /* If we have pending signals or status, and a new signal, enqueue the
3665 signal. Also enqueue the signal if we are waiting to reinsert a
3666 breakpoint; it will be picked up again below. */
3668 && (lwp
->status_pending_p
3669 || lwp
->pending_signals
!= NULL
3670 || lwp
->bp_reinsert
!= 0
3671 || fast_tp_collecting
))
3673 struct pending_signals
*p_sig
;
3674 p_sig
= xmalloc (sizeof (*p_sig
));
3675 p_sig
->prev
= lwp
->pending_signals
;
3676 p_sig
->signal
= signal
;
3678 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3680 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3681 lwp
->pending_signals
= p_sig
;
3684 if (lwp
->status_pending_p
)
3687 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
3688 " has pending status\n",
3689 lwpid_of (thread
), step
? "step" : "continue", signal
,
3690 lwp
->stop_expected
? "expected" : "not expected");
3694 saved_thread
= current_thread
;
3695 current_thread
= thread
;
3698 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
3699 lwpid_of (thread
), step
? "step" : "continue", signal
,
3700 lwp
->stop_expected
? "expected" : "not expected");
3702 /* This bit needs some thinking about. If we get a signal that
3703 we must report while a single-step reinsert is still pending,
3704 we often end up resuming the thread. It might be better to
3705 (ew) allow a stack of pending events; then we could be sure that
3706 the reinsert happened right away and not lose any signals.
3708 Making this stack would also shrink the window in which breakpoints are
3709 uninserted (see comment in linux_wait_for_lwp) but not enough for
3710 complete correctness, so it won't solve that problem. It may be
3711 worthwhile just to solve this one, however. */
3712 if (lwp
->bp_reinsert
!= 0)
3715 debug_printf (" pending reinsert at 0x%s\n",
3716 paddress (lwp
->bp_reinsert
));
3718 if (can_hardware_single_step ())
3720 if (fast_tp_collecting
== 0)
3723 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3725 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3732 /* Postpone any pending signal. It was enqueued above. */
3736 if (fast_tp_collecting
== 1)
3739 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3740 " (exit-jump-pad-bkpt)\n",
3743 /* Postpone any pending signal. It was enqueued above. */
3746 else if (fast_tp_collecting
== 2)
3749 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3750 " single-stepping\n",
3753 if (can_hardware_single_step ())
3757 internal_error (__FILE__
, __LINE__
,
3758 "moving out of jump pad single-stepping"
3759 " not implemented on this target");
3762 /* Postpone any pending signal. It was enqueued above. */
3766 /* If we have while-stepping actions in this thread set it stepping.
3767 If we have a signal to deliver, it may or may not be set to
3768 SIG_IGN, we don't know. Assume so, and allow collecting
3769 while-stepping into a signal handler. A possible smart thing to
3770 do would be to set an internal breakpoint at the signal return
3771 address, continue, and carry on catching this while-stepping
3772 action only when that breakpoint is hit. A future
3774 if (thread
->while_stepping
!= NULL
3775 && can_hardware_single_step ())
3778 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
3783 if (the_low_target
.get_pc
!= NULL
)
3785 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
3787 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
3791 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
3792 (long) lwp
->stop_pc
);
3796 /* If we have pending signals, consume one unless we are trying to
3797 reinsert a breakpoint or we're trying to finish a fast tracepoint
3799 if (lwp
->pending_signals
!= NULL
3800 && lwp
->bp_reinsert
== 0
3801 && fast_tp_collecting
== 0)
3803 struct pending_signals
**p_sig
;
3805 p_sig
= &lwp
->pending_signals
;
3806 while ((*p_sig
)->prev
!= NULL
)
3807 p_sig
= &(*p_sig
)->prev
;
3809 signal
= (*p_sig
)->signal
;
3810 if ((*p_sig
)->info
.si_signo
!= 0)
3811 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
3818 if (the_low_target
.prepare_to_resume
!= NULL
)
3819 the_low_target
.prepare_to_resume (lwp
);
3821 regcache_invalidate_thread (thread
);
3823 lwp
->stepping
= step
;
3824 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (thread
),
3825 (PTRACE_TYPE_ARG3
) 0,
3826 /* Coerce to a uintptr_t first to avoid potential gcc warning
3827 of coercing an 8 byte integer to a 4 byte pointer. */
3828 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
3830 current_thread
= saved_thread
;
3832 perror_with_name ("resuming thread");
3834 /* Successfully resumed. Clear state that no longer makes sense,
3835 and mark the LWP as running. Must not do this before resuming
3836 otherwise if that fails other code will be confused. E.g., we'd
3837 later try to stop the LWP and hang forever waiting for a stop
3838 status. Note that we must not throw after this is cleared,
3839 otherwise handle_zombie_lwp_error would get confused. */
3841 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3844 /* Called when we try to resume a stopped LWP and that errors out. If
3845 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
3846 or about to become), discard the error, clear any pending status
3847 the LWP may have, and return true (we'll collect the exit status
3848 soon enough). Otherwise, return false. */
3851 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
3853 struct thread_info
*thread
= get_lwp_thread (lp
);
3855 /* If we get an error after resuming the LWP successfully, we'd
3856 confuse !T state for the LWP being gone. */
3857 gdb_assert (lp
->stopped
);
3859 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
3860 because even if ptrace failed with ESRCH, the tracee may be "not
3861 yet fully dead", but already refusing ptrace requests. In that
3862 case the tracee has 'R (Running)' state for a little bit
3863 (observed in Linux 3.18). See also the note on ESRCH in the
3864 ptrace(2) man page. Instead, check whether the LWP has any state
3865 other than ptrace-stopped. */
3867 /* Don't assume anything if /proc/PID/status can't be read. */
3868 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
3870 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3871 lp
->status_pending_p
= 0;
3877 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
3878 disappears while we try to resume it. */
3881 linux_resume_one_lwp (struct lwp_info
*lwp
,
3882 int step
, int signal
, siginfo_t
*info
)
3886 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
3888 CATCH (ex
, RETURN_MASK_ERROR
)
3890 if (!check_ptrace_stopped_lwp_gone (lwp
))
3891 throw_exception (ex
);
3896 struct thread_resume_array
3898 struct thread_resume
*resume
;
3902 /* This function is called once per thread via find_inferior.
3903 ARG is a pointer to a thread_resume_array struct.
3904 We look up the thread specified by ENTRY in ARG, and mark the thread
3905 with a pointer to the appropriate resume request.
3907 This algorithm is O(threads * resume elements), but resume elements
3908 is small (and will remain small at least until GDB supports thread
3912 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3914 struct thread_info
*thread
= (struct thread_info
*) entry
;
3915 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3917 struct thread_resume_array
*r
;
3921 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3923 ptid_t ptid
= r
->resume
[ndx
].thread
;
3924 if (ptid_equal (ptid
, minus_one_ptid
)
3925 || ptid_equal (ptid
, entry
->id
)
3926 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3928 || (ptid_get_pid (ptid
) == pid_of (thread
)
3929 && (ptid_is_pid (ptid
)
3930 || ptid_get_lwp (ptid
) == -1)))
3932 if (r
->resume
[ndx
].kind
== resume_stop
3933 && thread
->last_resume_kind
== resume_stop
)
3936 debug_printf ("already %s LWP %ld at GDB's request\n",
3937 (thread
->last_status
.kind
3938 == TARGET_WAITKIND_STOPPED
)
3946 lwp
->resume
= &r
->resume
[ndx
];
3947 thread
->last_resume_kind
= lwp
->resume
->kind
;
3949 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
3950 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
3952 /* If we had a deferred signal to report, dequeue one now.
3953 This can happen if LWP gets more than one signal while
3954 trying to get out of a jump pad. */
3956 && !lwp
->status_pending_p
3957 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3959 lwp
->status_pending_p
= 1;
3962 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
3963 "leaving status pending.\n",
3964 WSTOPSIG (lwp
->status_pending
),
3972 /* No resume action for this thread. */
3978 /* find_inferior callback for linux_resume.
3979 Set *FLAG_P if this lwp has an interesting status pending. */
3982 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3984 struct thread_info
*thread
= (struct thread_info
*) entry
;
3985 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3987 /* LWPs which will not be resumed are not interesting, because
3988 we might not wait for them next time through linux_wait. */
3989 if (lwp
->resume
== NULL
)
3992 if (thread_still_has_status_pending_p (thread
))
3993 * (int *) flag_p
= 1;
3998 /* Return 1 if this lwp that GDB wants running is stopped at an
3999 internal breakpoint that we need to step over. It assumes that any
4000 required STOP_PC adjustment has already been propagated to the
4001 inferior's regcache. */
4004 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4006 struct thread_info
*thread
= (struct thread_info
*) entry
;
4007 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4008 struct thread_info
*saved_thread
;
4011 /* LWPs which will not be resumed are not interesting, because we
4012 might not wait for them next time through linux_wait. */
4017 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4022 if (thread
->last_resume_kind
== resume_stop
)
4025 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4031 gdb_assert (lwp
->suspended
>= 0);
4036 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4041 if (!lwp
->need_step_over
)
4044 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
4047 if (lwp
->status_pending_p
)
4050 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4056 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4060 /* If the PC has changed since we stopped, then don't do anything,
4061 and let the breakpoint/tracepoint be hit. This happens if, for
4062 instance, GDB handled the decr_pc_after_break subtraction itself,
4063 GDB is OOL stepping this thread, or the user has issued a "jump"
4064 command, or poked thread's registers herself. */
4065 if (pc
!= lwp
->stop_pc
)
4068 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4069 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4071 paddress (lwp
->stop_pc
), paddress (pc
));
4073 lwp
->need_step_over
= 0;
4077 saved_thread
= current_thread
;
4078 current_thread
= thread
;
4080 /* We can only step over breakpoints we know about. */
4081 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4083 /* Don't step over a breakpoint that GDB expects to hit
4084 though. If the condition is being evaluated on the target's side
4085 and it evaluate to false, step over this breakpoint as well. */
4086 if (gdb_breakpoint_here (pc
)
4087 && gdb_condition_true_at_breakpoint (pc
)
4088 && gdb_no_commands_at_breakpoint (pc
))
4091 debug_printf ("Need step over [LWP %ld]? yes, but found"
4092 " GDB breakpoint at 0x%s; skipping step over\n",
4093 lwpid_of (thread
), paddress (pc
));
4095 current_thread
= saved_thread
;
4101 debug_printf ("Need step over [LWP %ld]? yes, "
4102 "found breakpoint at 0x%s\n",
4103 lwpid_of (thread
), paddress (pc
));
4105 /* We've found an lwp that needs stepping over --- return 1 so
4106 that find_inferior stops looking. */
4107 current_thread
= saved_thread
;
4109 /* If the step over is cancelled, this is set again. */
4110 lwp
->need_step_over
= 0;
4115 current_thread
= saved_thread
;
4118 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4120 lwpid_of (thread
), paddress (pc
));
4125 /* Start a step-over operation on LWP. When LWP stopped at a
4126 breakpoint, to make progress, we need to remove the breakpoint out
4127 of the way. If we let other threads run while we do that, they may
4128 pass by the breakpoint location and miss hitting it. To avoid
4129 that, a step-over momentarily stops all threads while LWP is
4130 single-stepped while the breakpoint is temporarily uninserted from
4131 the inferior. When the single-step finishes, we reinsert the
4132 breakpoint, and let all threads that are supposed to be running,
4135 On targets that don't support hardware single-step, we don't
4136 currently support full software single-stepping. Instead, we only
4137 support stepping over the thread event breakpoint, by asking the
4138 low target where to place a reinsert breakpoint. Since this
4139 routine assumes the breakpoint being stepped over is a thread event
4140 breakpoint, it usually assumes the return address of the current
4141 function is a good enough place to set the reinsert breakpoint. */
4144 start_step_over (struct lwp_info
*lwp
)
4146 struct thread_info
*thread
= get_lwp_thread (lwp
);
4147 struct thread_info
*saved_thread
;
4152 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4155 stop_all_lwps (1, lwp
);
4156 gdb_assert (lwp
->suspended
== 0);
4159 debug_printf ("Done stopping all threads for step-over.\n");
4161 /* Note, we should always reach here with an already adjusted PC,
4162 either by GDB (if we're resuming due to GDB's request), or by our
4163 caller, if we just finished handling an internal breakpoint GDB
4164 shouldn't care about. */
4167 saved_thread
= current_thread
;
4168 current_thread
= thread
;
4170 lwp
->bp_reinsert
= pc
;
4171 uninsert_breakpoints_at (pc
);
4172 uninsert_fast_tracepoint_jumps_at (pc
);
4174 if (can_hardware_single_step ())
4180 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
4181 set_reinsert_breakpoint (raddr
);
4185 current_thread
= saved_thread
;
4187 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4189 /* Require next event from this LWP. */
4190 step_over_bkpt
= thread
->entry
.id
;
4194 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4195 start_step_over, if still there, and delete any reinsert
4196 breakpoints we've set, on non hardware single-step targets. */
4199 finish_step_over (struct lwp_info
*lwp
)
4201 if (lwp
->bp_reinsert
!= 0)
4204 debug_printf ("Finished step over.\n");
4206 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4207 may be no breakpoint to reinsert there by now. */
4208 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4209 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4211 lwp
->bp_reinsert
= 0;
4213 /* Delete any software-single-step reinsert breakpoints. No
4214 longer needed. We don't have to worry about other threads
4215 hitting this trap, and later not being able to explain it,
4216 because we were stepping over a breakpoint, and we hold all
4217 threads but LWP stopped while doing that. */
4218 if (!can_hardware_single_step ())
4219 delete_reinsert_breakpoints ();
4221 step_over_bkpt
= null_ptid
;
4228 /* This function is called once per thread. We check the thread's resume
4229 request, which will tell us whether to resume, step, or leave the thread
4230 stopped; and what signal, if any, it should be sent.
4232 For threads which we aren't explicitly told otherwise, we preserve
4233 the stepping flag; this is used for stepping over gdbserver-placed
4236 If pending_flags was set in any thread, we queue any needed
4237 signals, since we won't actually resume. We already have a pending
4238 event to report, so we don't need to preserve any step requests;
4239 they should be re-issued if necessary. */
4242 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4244 struct thread_info
*thread
= (struct thread_info
*) entry
;
4245 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4247 int leave_all_stopped
= * (int *) arg
;
4250 if (lwp
->resume
== NULL
)
4253 if (lwp
->resume
->kind
== resume_stop
)
4256 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4261 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4263 /* Stop the thread, and wait for the event asynchronously,
4264 through the event loop. */
4270 debug_printf ("already stopped LWP %ld\n",
4273 /* The LWP may have been stopped in an internal event that
4274 was not meant to be notified back to GDB (e.g., gdbserver
4275 breakpoint), so we should be reporting a stop event in
4278 /* If the thread already has a pending SIGSTOP, this is a
4279 no-op. Otherwise, something later will presumably resume
4280 the thread and this will cause it to cancel any pending
4281 operation, due to last_resume_kind == resume_stop. If
4282 the thread already has a pending status to report, we
4283 will still report it the next time we wait - see
4284 status_pending_p_callback. */
4286 /* If we already have a pending signal to report, then
4287 there's no need to queue a SIGSTOP, as this means we're
4288 midway through moving the LWP out of the jumppad, and we
4289 will report the pending signal as soon as that is
4291 if (lwp
->pending_signals_to_report
== NULL
)
4295 /* For stop requests, we're done. */
4297 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4301 /* If this thread which is about to be resumed has a pending status,
4302 then don't resume any threads - we can just report the pending
4303 status. Make sure to queue any signals that would otherwise be
4304 sent. In all-stop mode, we do this decision based on if *any*
4305 thread has a pending status. If there's a thread that needs the
4306 step-over-breakpoint dance, then don't resume any other thread
4307 but that particular one. */
4308 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
4313 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4315 step
= (lwp
->resume
->kind
== resume_step
);
4316 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4321 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4323 /* If we have a new signal, enqueue the signal. */
4324 if (lwp
->resume
->sig
!= 0)
4326 struct pending_signals
*p_sig
;
4327 p_sig
= xmalloc (sizeof (*p_sig
));
4328 p_sig
->prev
= lwp
->pending_signals
;
4329 p_sig
->signal
= lwp
->resume
->sig
;
4330 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4332 /* If this is the same signal we were previously stopped by,
4333 make sure to queue its siginfo. We can ignore the return
4334 value of ptrace; if it fails, we'll skip
4335 PTRACE_SETSIGINFO. */
4336 if (WIFSTOPPED (lwp
->last_status
)
4337 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4338 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4341 lwp
->pending_signals
= p_sig
;
4345 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4351 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4353 struct thread_resume_array array
= { resume_info
, n
};
4354 struct thread_info
*need_step_over
= NULL
;
4356 int leave_all_stopped
;
4361 debug_printf ("linux_resume:\n");
4364 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4366 /* If there is a thread which would otherwise be resumed, which has
4367 a pending status, then don't resume any threads - we can just
4368 report the pending status. Make sure to queue any signals that
4369 would otherwise be sent. In non-stop mode, we'll apply this
4370 logic to each thread individually. We consume all pending events
4371 before considering to start a step-over (in all-stop). */
4374 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4376 /* If there is a thread which would otherwise be resumed, which is
4377 stopped at a breakpoint that needs stepping over, then don't
4378 resume any threads - have it step over the breakpoint with all
4379 other threads stopped, then resume all threads again. Make sure
4380 to queue any signals that would otherwise be delivered or
4382 if (!any_pending
&& supports_breakpoints ())
4384 = (struct thread_info
*) find_inferior (&all_threads
,
4385 need_step_over_p
, NULL
);
4387 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4391 if (need_step_over
!= NULL
)
4392 debug_printf ("Not resuming all, need step over\n");
4393 else if (any_pending
)
4394 debug_printf ("Not resuming, all-stop and found "
4395 "an LWP with pending status\n");
4397 debug_printf ("Resuming, no pending status or step over needed\n");
4400 /* Even if we're leaving threads stopped, queue all signals we'd
4401 otherwise deliver. */
4402 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4405 start_step_over (get_thread_lwp (need_step_over
));
4409 debug_printf ("linux_resume done\n");
4414 /* This function is called once per thread. We check the thread's
4415 last resume request, which will tell us whether to resume, step, or
4416 leave the thread stopped. Any signal the client requested to be
4417 delivered has already been enqueued at this point.
4419 If any thread that GDB wants running is stopped at an internal
4420 breakpoint that needs stepping over, we start a step-over operation
4421 on that particular thread, and leave all others stopped. */
4424 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4426 struct thread_info
*thread
= (struct thread_info
*) entry
;
4427 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4434 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4439 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4443 if (thread
->last_resume_kind
== resume_stop
4444 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4447 debug_printf (" client wants LWP to remain %ld stopped\n",
4452 if (lwp
->status_pending_p
)
4455 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4460 gdb_assert (lwp
->suspended
>= 0);
4465 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4469 if (thread
->last_resume_kind
== resume_stop
4470 && lwp
->pending_signals_to_report
== NULL
4471 && lwp
->collecting_fast_tracepoint
== 0)
4473 /* We haven't reported this LWP as stopped yet (otherwise, the
4474 last_status.kind check above would catch it, and we wouldn't
4475 reach here. This LWP may have been momentarily paused by a
4476 stop_all_lwps call while handling for example, another LWP's
4477 step-over. In that case, the pending expected SIGSTOP signal
4478 that was queued at vCont;t handling time will have already
4479 been consumed by wait_for_sigstop, and so we need to requeue
4480 another one here. Note that if the LWP already has a SIGSTOP
4481 pending, this is a no-op. */
4484 debug_printf ("Client wants LWP %ld to stop. "
4485 "Making sure it has a SIGSTOP pending\n",
4491 step
= thread
->last_resume_kind
== resume_step
;
4492 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4497 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4499 struct thread_info
*thread
= (struct thread_info
*) entry
;
4500 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4506 gdb_assert (lwp
->suspended
>= 0);
4508 return proceed_one_lwp (entry
, except
);
4511 /* When we finish a step-over, set threads running again. If there's
4512 another thread that may need a step-over, now's the time to start
4513 it. Eventually, we'll move all threads past their breakpoints. */
4516 proceed_all_lwps (void)
4518 struct thread_info
*need_step_over
;
4520 /* If there is a thread which would otherwise be resumed, which is
4521 stopped at a breakpoint that needs stepping over, then don't
4522 resume any threads - have it step over the breakpoint with all
4523 other threads stopped, then resume all threads again. */
4525 if (supports_breakpoints ())
4528 = (struct thread_info
*) find_inferior (&all_threads
,
4529 need_step_over_p
, NULL
);
4531 if (need_step_over
!= NULL
)
4534 debug_printf ("proceed_all_lwps: found "
4535 "thread %ld needing a step-over\n",
4536 lwpid_of (need_step_over
));
4538 start_step_over (get_thread_lwp (need_step_over
));
4544 debug_printf ("Proceeding, no step-over needed\n");
4546 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
4549 /* Stopped LWPs that the client wanted to be running, that don't have
4550 pending statuses, are set to run again, except for EXCEPT, if not
4551 NULL. This undoes a stop_all_lwps call. */
4554 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
4560 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
4561 lwpid_of (get_lwp_thread (except
)));
4563 debug_printf ("unstopping all lwps\n");
4567 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
4569 find_inferior (&all_threads
, proceed_one_lwp
, except
);
4573 debug_printf ("unstop_all_lwps done\n");
4579 #ifdef HAVE_LINUX_REGSETS
4581 #define use_linux_regsets 1
4583 /* Returns true if REGSET has been disabled. */
4586 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4588 return (info
->disabled_regsets
!= NULL
4589 && info
->disabled_regsets
[regset
- info
->regsets
]);
4592 /* Disable REGSET. */
4595 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
4599 dr_offset
= regset
- info
->regsets
;
4600 if (info
->disabled_regsets
== NULL
)
4601 info
->disabled_regsets
= xcalloc (1, info
->num_regsets
);
4602 info
->disabled_regsets
[dr_offset
] = 1;
4606 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4607 struct regcache
*regcache
)
4609 struct regset_info
*regset
;
4610 int saw_general_regs
= 0;
4614 pid
= lwpid_of (current_thread
);
4615 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4620 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4623 buf
= xmalloc (regset
->size
);
4625 nt_type
= regset
->nt_type
;
4629 iov
.iov_len
= regset
->size
;
4630 data
= (void *) &iov
;
4636 res
= ptrace (regset
->get_request
, pid
,
4637 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4639 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4645 /* If we get EIO on a regset, do not try it again for
4646 this process mode. */
4647 disable_regset (regsets_info
, regset
);
4649 else if (errno
== ENODATA
)
4651 /* ENODATA may be returned if the regset is currently
4652 not "active". This can happen in normal operation,
4653 so suppress the warning in this case. */
4658 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4665 if (regset
->type
== GENERAL_REGS
)
4666 saw_general_regs
= 1;
4667 regset
->store_function (regcache
, buf
);
4671 if (saw_general_regs
)
4678 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
4679 struct regcache
*regcache
)
4681 struct regset_info
*regset
;
4682 int saw_general_regs
= 0;
4686 pid
= lwpid_of (current_thread
);
4687 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4692 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
4693 || regset
->fill_function
== NULL
)
4696 buf
= xmalloc (regset
->size
);
4698 /* First fill the buffer with the current register set contents,
4699 in case there are any items in the kernel's regset that are
4700 not in gdbserver's regcache. */
4702 nt_type
= regset
->nt_type
;
4706 iov
.iov_len
= regset
->size
;
4707 data
= (void *) &iov
;
4713 res
= ptrace (regset
->get_request
, pid
,
4714 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4716 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4721 /* Then overlay our cached registers on that. */
4722 regset
->fill_function (regcache
, buf
);
4724 /* Only now do we write the register set. */
4726 res
= ptrace (regset
->set_request
, pid
,
4727 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4729 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4737 /* If we get EIO on a regset, do not try it again for
4738 this process mode. */
4739 disable_regset (regsets_info
, regset
);
4741 else if (errno
== ESRCH
)
4743 /* At this point, ESRCH should mean the process is
4744 already gone, in which case we simply ignore attempts
4745 to change its registers. See also the related
4746 comment in linux_resume_one_lwp. */
4752 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4755 else if (regset
->type
== GENERAL_REGS
)
4756 saw_general_regs
= 1;
4759 if (saw_general_regs
)
4765 #else /* !HAVE_LINUX_REGSETS */
4767 #define use_linux_regsets 0
4768 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4769 #define regsets_store_inferior_registers(regsets_info, regcache) 1
4773 /* Return 1 if register REGNO is supported by one of the regset ptrace
4774 calls or 0 if it has to be transferred individually. */
4777 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
4779 unsigned char mask
= 1 << (regno
% 8);
4780 size_t index
= regno
/ 8;
4782 return (use_linux_regsets
4783 && (regs_info
->regset_bitmap
== NULL
4784 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
4787 #ifdef HAVE_LINUX_USRREGS
4790 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
4794 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
4795 error ("Invalid register number %d.", regnum
);
4797 addr
= usrregs
->regmap
[regnum
];
4802 /* Fetch one register. */
4804 fetch_register (const struct usrregs_info
*usrregs
,
4805 struct regcache
*regcache
, int regno
)
4812 if (regno
>= usrregs
->num_regs
)
4814 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4817 regaddr
= register_addr (usrregs
, regno
);
4821 size
= ((register_size (regcache
->tdesc
, regno
)
4822 + sizeof (PTRACE_XFER_TYPE
) - 1)
4823 & -sizeof (PTRACE_XFER_TYPE
));
4824 buf
= alloca (size
);
4826 pid
= lwpid_of (current_thread
);
4827 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4830 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4831 ptrace (PTRACE_PEEKUSER
, pid
,
4832 /* Coerce to a uintptr_t first to avoid potential gcc warning
4833 of coercing an 8 byte integer to a 4 byte pointer. */
4834 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
4835 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4837 error ("reading register %d: %s", regno
, strerror (errno
));
4840 if (the_low_target
.supply_ptrace_register
)
4841 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4843 supply_register (regcache
, regno
, buf
);
4846 /* Store one register. */
4848 store_register (const struct usrregs_info
*usrregs
,
4849 struct regcache
*regcache
, int regno
)
4856 if (regno
>= usrregs
->num_regs
)
4858 if ((*the_low_target
.cannot_store_register
) (regno
))
4861 regaddr
= register_addr (usrregs
, regno
);
4865 size
= ((register_size (regcache
->tdesc
, regno
)
4866 + sizeof (PTRACE_XFER_TYPE
) - 1)
4867 & -sizeof (PTRACE_XFER_TYPE
));
4868 buf
= alloca (size
);
4869 memset (buf
, 0, size
);
4871 if (the_low_target
.collect_ptrace_register
)
4872 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4874 collect_register (regcache
, regno
, buf
);
4876 pid
= lwpid_of (current_thread
);
4877 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4880 ptrace (PTRACE_POKEUSER
, pid
,
4881 /* Coerce to a uintptr_t first to avoid potential gcc warning
4882 about coercing an 8 byte integer to a 4 byte pointer. */
4883 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
4884 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4887 /* At this point, ESRCH should mean the process is
4888 already gone, in which case we simply ignore attempts
4889 to change its registers. See also the related
4890 comment in linux_resume_one_lwp. */
4894 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4895 error ("writing register %d: %s", regno
, strerror (errno
));
4897 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4901 /* Fetch all registers, or just one, from the child process.
4902 If REGNO is -1, do this for all registers, skipping any that are
4903 assumed to have been retrieved by regsets_fetch_inferior_registers,
4904 unless ALL is non-zero.
4905 Otherwise, REGNO specifies which register (so we can save time). */
4907 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
4908 struct regcache
*regcache
, int regno
, int all
)
4910 struct usrregs_info
*usr
= regs_info
->usrregs
;
4914 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4915 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4916 fetch_register (usr
, regcache
, regno
);
4919 fetch_register (usr
, regcache
, regno
);
4922 /* Store our register values back into the inferior.
4923 If REGNO is -1, do this for all registers, skipping any that are
4924 assumed to have been saved by regsets_store_inferior_registers,
4925 unless ALL is non-zero.
4926 Otherwise, REGNO specifies which register (so we can save time). */
4928 usr_store_inferior_registers (const struct regs_info
*regs_info
,
4929 struct regcache
*regcache
, int regno
, int all
)
4931 struct usrregs_info
*usr
= regs_info
->usrregs
;
4935 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4936 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4937 store_register (usr
, regcache
, regno
);
4940 store_register (usr
, regcache
, regno
);
4943 #else /* !HAVE_LINUX_USRREGS */
4945 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4946 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4952 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4956 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4960 if (the_low_target
.fetch_register
!= NULL
4961 && regs_info
->usrregs
!= NULL
)
4962 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
4963 (*the_low_target
.fetch_register
) (regcache
, regno
);
4965 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
4966 if (regs_info
->usrregs
!= NULL
)
4967 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
4971 if (the_low_target
.fetch_register
!= NULL
4972 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4975 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4977 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
4979 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4980 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
4985 linux_store_registers (struct regcache
*regcache
, int regno
)
4989 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4993 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4995 if (regs_info
->usrregs
!= NULL
)
4996 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5000 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5002 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5004 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5005 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5010 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5011 to debugger memory starting at MYADDR. */
5014 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5016 int pid
= lwpid_of (current_thread
);
5017 register PTRACE_XFER_TYPE
*buffer
;
5018 register CORE_ADDR addr
;
5025 /* Try using /proc. Don't bother for one word. */
5026 if (len
>= 3 * sizeof (long))
5030 /* We could keep this file open and cache it - possibly one per
5031 thread. That requires some juggling, but is even faster. */
5032 sprintf (filename
, "/proc/%d/mem", pid
);
5033 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5037 /* If pread64 is available, use it. It's faster if the kernel
5038 supports it (only one syscall), and it's 64-bit safe even on
5039 32-bit platforms (for instance, SPARC debugging a SPARC64
5042 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5045 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5046 bytes
= read (fd
, myaddr
, len
);
5053 /* Some data was read, we'll try to get the rest with ptrace. */
5063 /* Round starting address down to longword boundary. */
5064 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5065 /* Round ending address up; get number of longwords that makes. */
5066 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5067 / sizeof (PTRACE_XFER_TYPE
));
5068 /* Allocate buffer of that many longwords. */
5069 buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
5071 /* Read all the longwords */
5073 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5075 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5076 about coercing an 8 byte integer to a 4 byte pointer. */
5077 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5078 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5079 (PTRACE_TYPE_ARG4
) 0);
5085 /* Copy appropriate bytes out of the buffer. */
5088 i
*= sizeof (PTRACE_XFER_TYPE
);
5089 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5091 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5098 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5099 memory at MEMADDR. On failure (cannot write to the inferior)
5100 returns the value of errno. Always succeeds if LEN is zero. */
5103 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5106 /* Round starting address down to longword boundary. */
5107 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5108 /* Round ending address up; get number of longwords that makes. */
5110 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5111 / sizeof (PTRACE_XFER_TYPE
);
5113 /* Allocate buffer of that many longwords. */
5114 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
5115 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
5117 int pid
= lwpid_of (current_thread
);
5121 /* Zero length write always succeeds. */
5127 /* Dump up to four bytes. */
5128 unsigned int val
= * (unsigned int *) myaddr
;
5134 val
= val
& 0xffffff;
5135 debug_printf ("Writing %0*x to 0x%08lx in process %d\n",
5136 2 * ((len
< 4) ? len
: 4), val
, (long)memaddr
, pid
);
5139 /* Fill start and end extra bytes of buffer with existing memory data. */
5142 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5143 about coercing an 8 byte integer to a 4 byte pointer. */
5144 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5145 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5146 (PTRACE_TYPE_ARG4
) 0);
5154 = ptrace (PTRACE_PEEKTEXT
, pid
,
5155 /* Coerce to a uintptr_t first to avoid potential gcc warning
5156 about coercing an 8 byte integer to a 4 byte pointer. */
5157 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5158 * sizeof (PTRACE_XFER_TYPE
)),
5159 (PTRACE_TYPE_ARG4
) 0);
5164 /* Copy data to be written over corresponding part of buffer. */
5166 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5169 /* Write the entire buffer. */
5171 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5174 ptrace (PTRACE_POKETEXT
, pid
,
5175 /* Coerce to a uintptr_t first to avoid potential gcc warning
5176 about coercing an 8 byte integer to a 4 byte pointer. */
5177 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5178 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5187 linux_look_up_symbols (void)
5189 #ifdef USE_THREAD_DB
5190 struct process_info
*proc
= current_process ();
5192 if (proc
->priv
->thread_db
!= NULL
)
5195 /* If the kernel supports tracing clones, then we don't need to
5196 use the magic thread event breakpoint to learn about
5198 thread_db_init (!linux_supports_traceclone ());
5203 linux_request_interrupt (void)
5205 extern unsigned long signal_pid
;
5207 /* Send a SIGINT to the process group. This acts just like the user
5208 typed a ^C on the controlling terminal. */
5209 kill (-signal_pid
, SIGINT
);
5212 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5213 to debugger memory starting at MYADDR. */
5216 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5218 char filename
[PATH_MAX
];
5220 int pid
= lwpid_of (current_thread
);
5222 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5224 fd
= open (filename
, O_RDONLY
);
5228 if (offset
!= (CORE_ADDR
) 0
5229 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5232 n
= read (fd
, myaddr
, len
);
5239 /* These breakpoint and watchpoint related wrapper functions simply
5240 pass on the function call if the target has registered a
5241 corresponding function. */
5244 linux_supports_z_point_type (char z_type
)
5246 return (the_low_target
.supports_z_point_type
!= NULL
5247 && the_low_target
.supports_z_point_type (z_type
));
5251 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5252 int size
, struct raw_breakpoint
*bp
)
5254 if (type
== raw_bkpt_type_sw
)
5255 return insert_memory_breakpoint (bp
);
5256 else if (the_low_target
.insert_point
!= NULL
)
5257 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5259 /* Unsupported (see target.h). */
5264 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5265 int size
, struct raw_breakpoint
*bp
)
5267 if (type
== raw_bkpt_type_sw
)
5268 return remove_memory_breakpoint (bp
);
5269 else if (the_low_target
.remove_point
!= NULL
)
5270 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5272 /* Unsupported (see target.h). */
5276 /* Implement the to_stopped_by_sw_breakpoint target_ops
5280 linux_stopped_by_sw_breakpoint (void)
5282 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5284 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5287 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5291 linux_supports_stopped_by_sw_breakpoint (void)
5293 return USE_SIGTRAP_SIGINFO
;
5296 /* Implement the to_stopped_by_hw_breakpoint target_ops
5300 linux_stopped_by_hw_breakpoint (void)
5302 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5304 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5307 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5311 linux_supports_stopped_by_hw_breakpoint (void)
5313 return USE_SIGTRAP_SIGINFO
;
5316 /* Implement the supports_conditional_breakpoints target_ops
5320 linux_supports_conditional_breakpoints (void)
5322 /* GDBserver needs to step over the breakpoint if the condition is
5323 false. GDBserver software single step is too simple, so disable
5324 conditional breakpoints if the target doesn't have hardware single
5326 return can_hardware_single_step ();
5330 linux_stopped_by_watchpoint (void)
5332 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5334 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5338 linux_stopped_data_address (void)
5340 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5342 return lwp
->stopped_data_address
;
5345 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5346 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5347 && defined(PT_TEXT_END_ADDR)
5349 /* This is only used for targets that define PT_TEXT_ADDR,
5350 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5351 the target has different ways of acquiring this information, like
5354 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5355 to tell gdb about. */
5358 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5360 unsigned long text
, text_end
, data
;
5361 int pid
= lwpid_of (current_thread
);
5365 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5366 (PTRACE_TYPE_ARG4
) 0);
5367 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5368 (PTRACE_TYPE_ARG4
) 0);
5369 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5370 (PTRACE_TYPE_ARG4
) 0);
5374 /* Both text and data offsets produced at compile-time (and so
5375 used by gdb) are relative to the beginning of the program,
5376 with the data segment immediately following the text segment.
5377 However, the actual runtime layout in memory may put the data
5378 somewhere else, so when we send gdb a data base-address, we
5379 use the real data base address and subtract the compile-time
5380 data base-address from it (which is just the length of the
5381 text segment). BSS immediately follows data in both
5384 *data_p
= data
- (text_end
- text
);
5393 linux_qxfer_osdata (const char *annex
,
5394 unsigned char *readbuf
, unsigned const char *writebuf
,
5395 CORE_ADDR offset
, int len
)
5397 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5400 /* Convert a native/host siginfo object, into/from the siginfo in the
5401 layout of the inferiors' architecture. */
5404 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
5408 if (the_low_target
.siginfo_fixup
!= NULL
)
5409 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5411 /* If there was no callback, or the callback didn't do anything,
5412 then just do a straight memcpy. */
5416 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5418 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5423 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
5424 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
5428 char inf_siginfo
[sizeof (siginfo_t
)];
5430 if (current_thread
== NULL
)
5433 pid
= lwpid_of (current_thread
);
5436 debug_printf ("%s siginfo for lwp %d.\n",
5437 readbuf
!= NULL
? "Reading" : "Writing",
5440 if (offset
>= sizeof (siginfo
))
5443 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5446 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5447 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5448 inferior with a 64-bit GDBSERVER should look the same as debugging it
5449 with a 32-bit GDBSERVER, we need to convert it. */
5450 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5452 if (offset
+ len
> sizeof (siginfo
))
5453 len
= sizeof (siginfo
) - offset
;
5455 if (readbuf
!= NULL
)
5456 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5459 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5461 /* Convert back to ptrace layout before flushing it out. */
5462 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5464 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5471 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5472 so we notice when children change state; as the handler for the
5473 sigsuspend in my_waitpid. */
5476 sigchld_handler (int signo
)
5478 int old_errno
= errno
;
5484 /* fprintf is not async-signal-safe, so call write
5486 if (write (2, "sigchld_handler\n",
5487 sizeof ("sigchld_handler\n") - 1) < 0)
5488 break; /* just ignore */
5492 if (target_is_async_p ())
5493 async_file_mark (); /* trigger a linux_wait */
5499 linux_supports_non_stop (void)
5505 linux_async (int enable
)
5507 int previous
= target_is_async_p ();
5510 debug_printf ("linux_async (%d), previous=%d\n",
5513 if (previous
!= enable
)
5516 sigemptyset (&mask
);
5517 sigaddset (&mask
, SIGCHLD
);
5519 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
5523 if (pipe (linux_event_pipe
) == -1)
5525 linux_event_pipe
[0] = -1;
5526 linux_event_pipe
[1] = -1;
5527 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5529 warning ("creating event pipe failed.");
5533 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5534 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5536 /* Register the event loop handler. */
5537 add_file_handler (linux_event_pipe
[0],
5538 handle_target_event
, NULL
);
5540 /* Always trigger a linux_wait. */
5545 delete_file_handler (linux_event_pipe
[0]);
5547 close (linux_event_pipe
[0]);
5548 close (linux_event_pipe
[1]);
5549 linux_event_pipe
[0] = -1;
5550 linux_event_pipe
[1] = -1;
5553 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5560 linux_start_non_stop (int nonstop
)
5562 /* Register or unregister from event-loop accordingly. */
5563 linux_async (nonstop
);
5565 if (target_is_async_p () != (nonstop
!= 0))
5572 linux_supports_multi_process (void)
5577 /* Check if fork events are supported. */
5580 linux_supports_fork_events (void)
5582 return linux_supports_tracefork ();
5585 /* Check if vfork events are supported. */
5588 linux_supports_vfork_events (void)
5590 return linux_supports_tracefork ();
5593 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
5594 options for the specified lwp. */
5597 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
5600 struct thread_info
*thread
= (struct thread_info
*) entry
;
5601 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5605 /* Stop the lwp so we can modify its ptrace options. */
5606 lwp
->must_set_ptrace_flags
= 1;
5607 linux_stop_lwp (lwp
);
5611 /* Already stopped; go ahead and set the ptrace options. */
5612 struct process_info
*proc
= find_process_pid (pid_of (thread
));
5613 int options
= linux_low_ptrace_options (proc
->attached
);
5615 linux_enable_event_reporting (lwpid_of (thread
), options
);
5616 lwp
->must_set_ptrace_flags
= 0;
5622 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
5623 ptrace flags for all inferiors. This is in case the new GDB connection
5624 doesn't support the same set of events that the previous one did. */
5627 linux_handle_new_gdb_connection (void)
5631 /* Request that all the lwps reset their ptrace options. */
5632 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
5636 linux_supports_disable_randomization (void)
5638 #ifdef HAVE_PERSONALITY
5646 linux_supports_agent (void)
5652 linux_supports_range_stepping (void)
5654 if (*the_low_target
.supports_range_stepping
== NULL
)
5657 return (*the_low_target
.supports_range_stepping
) ();
5660 /* Enumerate spufs IDs for process PID. */
5662 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
5668 struct dirent
*entry
;
5670 sprintf (path
, "/proc/%ld/fd", pid
);
5671 dir
= opendir (path
);
5676 while ((entry
= readdir (dir
)) != NULL
)
5682 fd
= atoi (entry
->d_name
);
5686 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
5687 if (stat (path
, &st
) != 0)
5689 if (!S_ISDIR (st
.st_mode
))
5692 if (statfs (path
, &stfs
) != 0)
5694 if (stfs
.f_type
!= SPUFS_MAGIC
)
5697 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5699 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5709 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5710 object type, using the /proc file system. */
5712 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5713 unsigned const char *writebuf
,
5714 CORE_ADDR offset
, int len
)
5716 long pid
= lwpid_of (current_thread
);
5721 if (!writebuf
&& !readbuf
)
5729 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5732 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5733 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5738 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5745 ret
= write (fd
, writebuf
, (size_t) len
);
5747 ret
= read (fd
, readbuf
, (size_t) len
);
5753 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5754 struct target_loadseg
5756 /* Core address to which the segment is mapped. */
5758 /* VMA recorded in the program header. */
5760 /* Size of this segment in memory. */
5764 # if defined PT_GETDSBT
5765 struct target_loadmap
5767 /* Protocol version number, must be zero. */
5769 /* Pointer to the DSBT table, its size, and the DSBT index. */
5770 unsigned *dsbt_table
;
5771 unsigned dsbt_size
, dsbt_index
;
5772 /* Number of segments in this map. */
5774 /* The actual memory map. */
5775 struct target_loadseg segs
[/*nsegs*/];
5777 # define LINUX_LOADMAP PT_GETDSBT
5778 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5779 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5781 struct target_loadmap
5783 /* Protocol version number, must be zero. */
5785 /* Number of segments in this map. */
5787 /* The actual memory map. */
5788 struct target_loadseg segs
[/*nsegs*/];
5790 # define LINUX_LOADMAP PTRACE_GETFDPIC
5791 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5792 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5796 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5797 unsigned char *myaddr
, unsigned int len
)
5799 int pid
= lwpid_of (current_thread
);
5801 struct target_loadmap
*data
= NULL
;
5802 unsigned int actual_length
, copy_length
;
5804 if (strcmp (annex
, "exec") == 0)
5805 addr
= (int) LINUX_LOADMAP_EXEC
;
5806 else if (strcmp (annex
, "interp") == 0)
5807 addr
= (int) LINUX_LOADMAP_INTERP
;
5811 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5817 actual_length
= sizeof (struct target_loadmap
)
5818 + sizeof (struct target_loadseg
) * data
->nsegs
;
5820 if (offset
< 0 || offset
> actual_length
)
5823 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5824 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5828 # define linux_read_loadmap NULL
5829 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5832 linux_process_qsupported (const char *query
)
5834 if (the_low_target
.process_qsupported
!= NULL
)
5835 the_low_target
.process_qsupported (query
);
5839 linux_supports_tracepoints (void)
5841 if (*the_low_target
.supports_tracepoints
== NULL
)
5844 return (*the_low_target
.supports_tracepoints
) ();
5848 linux_read_pc (struct regcache
*regcache
)
5850 if (the_low_target
.get_pc
== NULL
)
5853 return (*the_low_target
.get_pc
) (regcache
);
5857 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5859 gdb_assert (the_low_target
.set_pc
!= NULL
);
5861 (*the_low_target
.set_pc
) (regcache
, pc
);
5865 linux_thread_stopped (struct thread_info
*thread
)
5867 return get_thread_lwp (thread
)->stopped
;
5870 /* This exposes stop-all-threads functionality to other modules. */
5873 linux_pause_all (int freeze
)
5875 stop_all_lwps (freeze
, NULL
);
5878 /* This exposes unstop-all-threads functionality to other gdbserver
5882 linux_unpause_all (int unfreeze
)
5884 unstop_all_lwps (unfreeze
, NULL
);
5888 linux_prepare_to_access_memory (void)
5890 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5893 linux_pause_all (1);
5898 linux_done_accessing_memory (void)
5900 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5903 linux_unpause_all (1);
5907 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5908 CORE_ADDR collector
,
5911 CORE_ADDR
*jump_entry
,
5912 CORE_ADDR
*trampoline
,
5913 ULONGEST
*trampoline_size
,
5914 unsigned char *jjump_pad_insn
,
5915 ULONGEST
*jjump_pad_insn_size
,
5916 CORE_ADDR
*adjusted_insn_addr
,
5917 CORE_ADDR
*adjusted_insn_addr_end
,
5920 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5921 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5922 jump_entry
, trampoline
, trampoline_size
,
5923 jjump_pad_insn
, jjump_pad_insn_size
,
5924 adjusted_insn_addr
, adjusted_insn_addr_end
,
5928 static struct emit_ops
*
5929 linux_emit_ops (void)
5931 if (the_low_target
.emit_ops
!= NULL
)
5932 return (*the_low_target
.emit_ops
) ();
5938 linux_get_min_fast_tracepoint_insn_len (void)
5940 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5943 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5946 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5947 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5949 char filename
[PATH_MAX
];
5951 const int auxv_size
= is_elf64
5952 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5953 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5955 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5957 fd
= open (filename
, O_RDONLY
);
5963 while (read (fd
, buf
, auxv_size
) == auxv_size
5964 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5968 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5970 switch (aux
->a_type
)
5973 *phdr_memaddr
= aux
->a_un
.a_val
;
5976 *num_phdr
= aux
->a_un
.a_val
;
5982 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5984 switch (aux
->a_type
)
5987 *phdr_memaddr
= aux
->a_un
.a_val
;
5990 *num_phdr
= aux
->a_un
.a_val
;
5998 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6000 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6001 "phdr_memaddr = %ld, phdr_num = %d",
6002 (long) *phdr_memaddr
, *num_phdr
);
6009 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6012 get_dynamic (const int pid
, const int is_elf64
)
6014 CORE_ADDR phdr_memaddr
, relocation
;
6016 unsigned char *phdr_buf
;
6017 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6019 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6022 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6023 phdr_buf
= alloca (num_phdr
* phdr_size
);
6025 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6028 /* Compute relocation: it is expected to be 0 for "regular" executables,
6029 non-zero for PIE ones. */
6031 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6034 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6036 if (p
->p_type
== PT_PHDR
)
6037 relocation
= phdr_memaddr
- p
->p_vaddr
;
6041 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6043 if (p
->p_type
== PT_PHDR
)
6044 relocation
= phdr_memaddr
- p
->p_vaddr
;
6047 if (relocation
== -1)
6049 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6050 any real world executables, including PIE executables, have always
6051 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6052 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6053 or present DT_DEBUG anyway (fpc binaries are statically linked).
6055 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6057 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6062 for (i
= 0; i
< num_phdr
; i
++)
6066 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6068 if (p
->p_type
== PT_DYNAMIC
)
6069 return p
->p_vaddr
+ relocation
;
6073 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6075 if (p
->p_type
== PT_DYNAMIC
)
6076 return p
->p_vaddr
+ relocation
;
6083 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6084 can be 0 if the inferior does not yet have the library list initialized.
6085 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6086 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6089 get_r_debug (const int pid
, const int is_elf64
)
6091 CORE_ADDR dynamic_memaddr
;
6092 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6093 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6096 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6097 if (dynamic_memaddr
== 0)
6100 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6104 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6105 #ifdef DT_MIPS_RLD_MAP
6109 unsigned char buf
[sizeof (Elf64_Xword
)];
6113 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6115 if (linux_read_memory (dyn
->d_un
.d_val
,
6116 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6121 #endif /* DT_MIPS_RLD_MAP */
6123 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6124 map
= dyn
->d_un
.d_val
;
6126 if (dyn
->d_tag
== DT_NULL
)
6131 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6132 #ifdef DT_MIPS_RLD_MAP
6136 unsigned char buf
[sizeof (Elf32_Word
)];
6140 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6142 if (linux_read_memory (dyn
->d_un
.d_val
,
6143 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6148 #endif /* DT_MIPS_RLD_MAP */
6150 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6151 map
= dyn
->d_un
.d_val
;
6153 if (dyn
->d_tag
== DT_NULL
)
6157 dynamic_memaddr
+= dyn_size
;
6163 /* Read one pointer from MEMADDR in the inferior. */
6166 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6170 /* Go through a union so this works on either big or little endian
6171 hosts, when the inferior's pointer size is smaller than the size
6172 of CORE_ADDR. It is assumed the inferior's endianness is the
6173 same of the superior's. */
6176 CORE_ADDR core_addr
;
6181 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6184 if (ptr_size
== sizeof (CORE_ADDR
))
6185 *ptr
= addr
.core_addr
;
6186 else if (ptr_size
== sizeof (unsigned int))
6189 gdb_assert_not_reached ("unhandled pointer size");
6194 struct link_map_offsets
6196 /* Offset and size of r_debug.r_version. */
6197 int r_version_offset
;
6199 /* Offset and size of r_debug.r_map. */
6202 /* Offset to l_addr field in struct link_map. */
6205 /* Offset to l_name field in struct link_map. */
6208 /* Offset to l_ld field in struct link_map. */
6211 /* Offset to l_next field in struct link_map. */
6214 /* Offset to l_prev field in struct link_map. */
6218 /* Construct qXfer:libraries-svr4:read reply. */
6221 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6222 unsigned const char *writebuf
,
6223 CORE_ADDR offset
, int len
)
6226 unsigned document_len
;
6227 struct process_info_private
*const priv
= current_process ()->priv
;
6228 char filename
[PATH_MAX
];
6231 static const struct link_map_offsets lmo_32bit_offsets
=
6233 0, /* r_version offset. */
6234 4, /* r_debug.r_map offset. */
6235 0, /* l_addr offset in link_map. */
6236 4, /* l_name offset in link_map. */
6237 8, /* l_ld offset in link_map. */
6238 12, /* l_next offset in link_map. */
6239 16 /* l_prev offset in link_map. */
6242 static const struct link_map_offsets lmo_64bit_offsets
=
6244 0, /* r_version offset. */
6245 8, /* r_debug.r_map offset. */
6246 0, /* l_addr offset in link_map. */
6247 8, /* l_name offset in link_map. */
6248 16, /* l_ld offset in link_map. */
6249 24, /* l_next offset in link_map. */
6250 32 /* l_prev offset in link_map. */
6252 const struct link_map_offsets
*lmo
;
6253 unsigned int machine
;
6255 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6256 int allocated
= 1024;
6258 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6259 int header_done
= 0;
6261 if (writebuf
!= NULL
)
6263 if (readbuf
== NULL
)
6266 pid
= lwpid_of (current_thread
);
6267 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6268 is_elf64
= elf_64_file_p (filename
, &machine
);
6269 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6270 ptr_size
= is_elf64
? 8 : 4;
6272 while (annex
[0] != '\0')
6278 sep
= strchr (annex
, '=');
6283 if (len
== 5 && startswith (annex
, "start"))
6285 else if (len
== 4 && startswith (annex
, "prev"))
6289 annex
= strchr (sep
, ';');
6296 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6303 if (priv
->r_debug
== 0)
6304 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6306 /* We failed to find DT_DEBUG. Such situation will not change
6307 for this inferior - do not retry it. Report it to GDB as
6308 E01, see for the reasons at the GDB solib-svr4.c side. */
6309 if (priv
->r_debug
== (CORE_ADDR
) -1)
6312 if (priv
->r_debug
!= 0)
6314 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6315 (unsigned char *) &r_version
,
6316 sizeof (r_version
)) != 0
6319 warning ("unexpected r_debug version %d", r_version
);
6321 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6322 &lm_addr
, ptr_size
) != 0)
6324 warning ("unable to read r_map from 0x%lx",
6325 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6330 document
= xmalloc (allocated
);
6331 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6332 p
= document
+ strlen (document
);
6335 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6336 &l_name
, ptr_size
) == 0
6337 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6338 &l_addr
, ptr_size
) == 0
6339 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6340 &l_ld
, ptr_size
) == 0
6341 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6342 &l_prev
, ptr_size
) == 0
6343 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6344 &l_next
, ptr_size
) == 0)
6346 unsigned char libname
[PATH_MAX
];
6348 if (lm_prev
!= l_prev
)
6350 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6351 (long) lm_prev
, (long) l_prev
);
6355 /* Ignore the first entry even if it has valid name as the first entry
6356 corresponds to the main executable. The first entry should not be
6357 skipped if the dynamic loader was loaded late by a static executable
6358 (see solib-svr4.c parameter ignore_first). But in such case the main
6359 executable does not have PT_DYNAMIC present and this function already
6360 exited above due to failed get_r_debug. */
6363 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6368 /* Not checking for error because reading may stop before
6369 we've got PATH_MAX worth of characters. */
6371 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6372 libname
[sizeof (libname
) - 1] = '\0';
6373 if (libname
[0] != '\0')
6375 /* 6x the size for xml_escape_text below. */
6376 size_t len
= 6 * strlen ((char *) libname
);
6381 /* Terminate `<library-list-svr4'. */
6386 while (allocated
< p
- document
+ len
+ 200)
6388 /* Expand to guarantee sufficient storage. */
6389 uintptr_t document_len
= p
- document
;
6391 document
= xrealloc (document
, 2 * allocated
);
6393 p
= document
+ document_len
;
6396 name
= xml_escape_text ((char *) libname
);
6397 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
6398 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6399 name
, (unsigned long) lm_addr
,
6400 (unsigned long) l_addr
, (unsigned long) l_ld
);
6411 /* Empty list; terminate `<library-list-svr4'. */
6415 strcpy (p
, "</library-list-svr4>");
6417 document_len
= strlen (document
);
6418 if (offset
< document_len
)
6419 document_len
-= offset
;
6422 if (len
> document_len
)
6425 memcpy (readbuf
, document
+ offset
, len
);
6431 #ifdef HAVE_LINUX_BTRACE
6433 /* See to_enable_btrace target method. */
6435 static struct btrace_target_info
*
6436 linux_low_enable_btrace (ptid_t ptid
, const struct btrace_config
*conf
)
6438 struct btrace_target_info
*tinfo
;
6440 tinfo
= linux_enable_btrace (ptid
, conf
);
6442 if (tinfo
!= NULL
&& tinfo
->ptr_bits
== 0)
6444 struct thread_info
*thread
= find_thread_ptid (ptid
);
6445 struct regcache
*regcache
= get_thread_regcache (thread
, 0);
6447 tinfo
->ptr_bits
= register_size (regcache
->tdesc
, 0) * 8;
6453 /* See to_disable_btrace target method. */
6456 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
6458 enum btrace_error err
;
6460 err
= linux_disable_btrace (tinfo
);
6461 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6464 /* See to_read_btrace target method. */
6467 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
6470 struct btrace_data btrace
;
6471 struct btrace_block
*block
;
6472 enum btrace_error err
;
6475 btrace_data_init (&btrace
);
6477 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6478 if (err
!= BTRACE_ERR_NONE
)
6480 if (err
== BTRACE_ERR_OVERFLOW
)
6481 buffer_grow_str0 (buffer
, "E.Overflow.");
6483 buffer_grow_str0 (buffer
, "E.Generic Error.");
6485 btrace_data_fini (&btrace
);
6489 switch (btrace
.format
)
6491 case BTRACE_FORMAT_NONE
:
6492 buffer_grow_str0 (buffer
, "E.No Trace.");
6495 case BTRACE_FORMAT_BTS
:
6496 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6497 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6500 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
6502 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6503 paddress (block
->begin
), paddress (block
->end
));
6505 buffer_grow_str0 (buffer
, "</btrace>\n");
6509 buffer_grow_str0 (buffer
, "E.Unknown Trace Format.");
6511 btrace_data_fini (&btrace
);
6515 btrace_data_fini (&btrace
);
6519 /* See to_btrace_conf target method. */
6522 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
6523 struct buffer
*buffer
)
6525 const struct btrace_config
*conf
;
6527 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6528 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
6530 conf
= linux_btrace_conf (tinfo
);
6533 switch (conf
->format
)
6535 case BTRACE_FORMAT_NONE
:
6538 case BTRACE_FORMAT_BTS
:
6539 buffer_xml_printf (buffer
, "<bts");
6540 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
6541 buffer_xml_printf (buffer
, " />\n");
6546 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
6549 #endif /* HAVE_LINUX_BTRACE */
6551 /* See nat/linux-nat.h. */
6554 current_lwp_ptid (void)
6556 return ptid_of (current_thread
);
6559 static struct target_ops linux_target_ops
= {
6560 linux_create_inferior
,
6569 linux_fetch_registers
,
6570 linux_store_registers
,
6571 linux_prepare_to_access_memory
,
6572 linux_done_accessing_memory
,
6575 linux_look_up_symbols
,
6576 linux_request_interrupt
,
6578 linux_supports_z_point_type
,
6581 linux_stopped_by_sw_breakpoint
,
6582 linux_supports_stopped_by_sw_breakpoint
,
6583 linux_stopped_by_hw_breakpoint
,
6584 linux_supports_stopped_by_hw_breakpoint
,
6585 linux_supports_conditional_breakpoints
,
6586 linux_stopped_by_watchpoint
,
6587 linux_stopped_data_address
,
6588 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6589 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6590 && defined(PT_TEXT_END_ADDR)
6595 #ifdef USE_THREAD_DB
6596 thread_db_get_tls_address
,
6601 hostio_last_error_from_errno
,
6604 linux_supports_non_stop
,
6606 linux_start_non_stop
,
6607 linux_supports_multi_process
,
6608 linux_supports_fork_events
,
6609 linux_supports_vfork_events
,
6610 linux_handle_new_gdb_connection
,
6611 #ifdef USE_THREAD_DB
6612 thread_db_handle_monitor_command
,
6616 linux_common_core_of_thread
,
6618 linux_process_qsupported
,
6619 linux_supports_tracepoints
,
6622 linux_thread_stopped
,
6626 linux_stabilize_threads
,
6627 linux_install_fast_tracepoint_jump_pad
,
6629 linux_supports_disable_randomization
,
6630 linux_get_min_fast_tracepoint_insn_len
,
6631 linux_qxfer_libraries_svr4
,
6632 linux_supports_agent
,
6633 #ifdef HAVE_LINUX_BTRACE
6634 linux_supports_btrace
,
6635 linux_low_enable_btrace
,
6636 linux_low_disable_btrace
,
6637 linux_low_read_btrace
,
6638 linux_low_btrace_conf
,
6646 linux_supports_range_stepping
,
6647 linux_proc_pid_to_exec_file
,
6648 linux_mntns_open_cloexec
,
6650 linux_mntns_readlink
,
6654 linux_init_signals ()
6656 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
6657 to find what the cancel signal actually is. */
6658 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
6659 signal (__SIGRTMIN
+1, SIG_IGN
);
6663 #ifdef HAVE_LINUX_REGSETS
6665 initialize_regsets_info (struct regsets_info
*info
)
6667 for (info
->num_regsets
= 0;
6668 info
->regsets
[info
->num_regsets
].size
>= 0;
6669 info
->num_regsets
++)
6675 initialize_low (void)
6677 struct sigaction sigchld_action
;
6678 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
6679 set_target_ops (&linux_target_ops
);
6680 set_breakpoint_data (the_low_target
.breakpoint
,
6681 the_low_target
.breakpoint_len
);
6682 linux_init_signals ();
6683 linux_ptrace_init_warnings ();
6685 sigchld_action
.sa_handler
= sigchld_handler
;
6686 sigemptyset (&sigchld_action
.sa_mask
);
6687 sigchld_action
.sa_flags
= SA_RESTART
;
6688 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
6690 initialize_low_arch ();
6692 linux_check_ptrace_features ();