/* Multi-threaded debugging support for GNU/Linux (LWP layer).
- Copyright 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+ Copyright 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of GDB.
memset (lp, 0, sizeof (struct lwp_info));
+ lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
+
lp->ptid = ptid;
lp->next = lwp_list;
void
lin_lwp_attach_lwp (ptid_t ptid, int verbose)
{
- struct lwp_info *lp;
+ struct lwp_info *lp, *found_lp;
gdb_assert (is_lwp (ptid));
if (verbose)
printf_filtered ("[New %s]\n", target_pid_to_str (ptid));
- lp = find_lwp_pid (ptid);
+ found_lp = lp = find_lwp_pid (ptid);
if (lp == NULL)
lp = add_lwp (ptid);
- /* We assume that we're already attached to any LWP that has an
- id equal to the overall process id. */
- if (GET_LWP (ptid) != GET_PID (ptid))
+ /* We assume that we're already attached to any LWP that has an id
+ equal to the overall process id, and to any LWP that is already
+ in our list of LWPs. If we're not seeing exit events from threads
+ and we've had PID wraparound since we last tried to stop all threads,
+ this assumption might be wrong; fortunately, this is very unlikely
+ to happen. */
+ if (GET_LWP (ptid) != GET_PID (ptid) && found_lp == NULL)
{
pid_t pid;
int status;
return kill (lwpid, signo);
}
+/* Handle a GNU/Linux extended wait response. Most of the work we
+ just pass off to linux_handle_extended_wait, but if it reports a
+ clone event we need to add the new LWP to our list (and not report
+ the trap to higher layers). This function returns non-zero if
+ the event should be ignored and we should wait again. */
+
+static int
+lin_lwp_handle_extended (struct lwp_info *lp, int status)
+{
+ linux_handle_extended_wait (GET_LWP (lp->ptid), status,
+ &lp->waitstatus);
+
+ /* TARGET_WAITKIND_SPURIOUS is used to indicate clone events. */
+ if (lp->waitstatus.kind == TARGET_WAITKIND_SPURIOUS)
+ {
+ struct lwp_info *new_lp;
+ new_lp = add_lwp (BUILD_LWP (lp->waitstatus.value.related_pid,
+ GET_PID (inferior_ptid)));
+ new_lp->cloned = 1;
+ new_lp->stopped = 1;
+
+ lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
+
+ if (debug_lin_lwp)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLHE: Got clone event from LWP %ld, resuming\n",
+ GET_LWP (lp->ptid));
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+
+ return 1;
+ }
+
+ return 0;
+}
+
/* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
exited. */
pid = waitpid (GET_LWP (lp->ptid), &status, __WCLONE);
if (pid == -1 && errno == ECHILD)
{
- /* The thread has previously exited. We need to delete it now
- because in the case of NPTL threads, there won't be an
- exit event unless it is the main thread. */
+ /* The thread has previously exited. We need to delete it
+ now because, for some vendor 2.4 kernels with NPTL
+ support backported, there won't be an exit event unless
+ it is the main thread. 2.6 kernels will report an exit
+ event for each thread that exits, as expected. */
thread_dead = 1;
if (debug_lin_lwp)
fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n",
gdb_assert (WIFSTOPPED (status));
+ /* Handle GNU/Linux's extended waitstatus for trace events. */
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
+ {
+ if (debug_lin_lwp)
+ fprintf_unfiltered (gdb_stdlog,
+ "WL: Handling extended status 0x%06x\n",
+ status);
+ if (lin_lwp_handle_extended (lp, status))
+ return wait_lwp (lp);
+ }
+
return status;
}
int status;
pid_t pid;
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+
do
{
set_sigint_trap (); /* Causes SIGINT to be passed on to the
save_errno = EINTR;
}
+ /* Handle GNU/Linux's extended waitstatus for trace events. */
+ if (pid != -1 && WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP
+ && status >> 16 != 0)
+ {
+ linux_handle_extended_wait (pid, status, ourstatus);
+
+ /* If we see a clone event, detach the child, and don't
+ report the event. It would be nice to offer some way to
+ switch into a non-thread-db based threaded mode at this
+ point. */
+ if (ourstatus->kind == TARGET_WAITKIND_SPURIOUS)
+ {
+ ptrace (PTRACE_DETACH, ourstatus->value.related_pid, 0, 0);
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+ pid = -1;
+ save_errno = EINTR;
+ }
+ }
+
clear_sigio_trap ();
clear_sigint_trap ();
}
return minus_one_ptid;
}
- /* Handle GNU/Linux's extended waitstatus for trace events. */
- if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
- return linux_handle_extended_wait (pid, status, ourstatus);
+ if (ourstatus->kind == TARGET_WAITKIND_IGNORE)
+ store_waitstatus (ourstatus, status);
- store_waitstatus (ourstatus, status);
return pid_to_ptid (pid);
}
}
}
+ /* Handle GNU/Linux's extended waitstatus for trace events. */
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
+ {
+ if (debug_lin_lwp)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Handling extended status 0x%06x\n",
+ status);
+ if (lin_lwp_handle_extended (lp, status))
+ {
+ status = 0;
+ continue;
+ }
+ }
+
/* Check if the thread has exited. */
if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1)
{
else
trap_ptid = null_ptid;
- /* Handle GNU/Linux's extended waitstatus for trace events. */
- if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
+ if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
{
- linux_handle_extended_wait (GET_LWP (lp->ptid), status, ourstatus);
- return trap_ptid;
+ *ourstatus = lp->waitstatus;
+ lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
}
+ else
+ store_waitstatus (ourstatus, status);
- store_waitstatus (ourstatus, status);
return (threaded ? lp->ptid : pid_to_ptid (GET_LWP (lp->ptid)));
}
projects / deliverable / binutils-gdb.git / blobdiff