/* libthread_db assisted debugging support, generic parts.
- Copyright (C) 1999-2015 Free Software Foundation, Inc.
+ Copyright (C) 1999-2017 Free Software Foundation, Inc.
This file is part of GDB.
#include "nat/linux-osdata.h"
#include "auto-load.h"
#include "cli/cli-utils.h"
-
#include <signal.h>
#include <ctype.h>
+#include "nat/linux-namespaces.h"
+#include <algorithm>
/* GNU/Linux libthread_db support.
created, thread IDs (usually, the result of pthread_self), and
thread-local variables.
- The libthread_db interface originates on Solaris, where it is
- both more powerful and more complicated. This implementation
- only works for LinuxThreads and NPTL, the two glibc threading
- libraries. It assumes that each thread is permanently assigned
- to a single light-weight process (LWP).
+ The libthread_db interface originates on Solaris, where it is both
+ more powerful and more complicated. This implementation only works
+ for NPTL, the glibc threading library. It assumes that each thread
+ is permanently assigned to a single light-weight process (LWP). At
+ some point it also supported the older LinuxThreads library, but it
+ no longer does.
libthread_db-specific information is stored in the "private" field
of struct thread_info. When the field is NULL we do not yet have
by the "set auto-load libthread-db" command. */
static int auto_load_thread_db = 1;
-/* Returns true if we need to use thread_db thread create/death event
- breakpoints to learn about threads. */
-
-static int
-thread_db_use_events (void)
-{
- /* Not necessary if the kernel supports clone events. */
- return !linux_supports_traceclone ();
-}
-
/* "show" command for the auto_load_thread_db configuration variable. */
static void
}
static void
-set_libthread_db_search_path (char *ignored, int from_tty,
+set_libthread_db_search_path (const char *ignored, int from_tty,
struct cmd_list_element *c)
{
if (*libthread_db_search_path == '\0')
be able to ignore such stale entries. */
int need_stale_parent_threads_check;
- /* Location of the thread creation event breakpoint. The code at
- this location in the child process will be called by the pthread
- library whenever a new thread is created. By setting a special
- breakpoint at this location, GDB can detect when a new thread is
- created. We obtain this location via the td_ta_event_addr
- call. */
- CORE_ADDR td_create_bp_addr;
-
- /* Location of the thread death event breakpoint. */
- CORE_ADDR td_death_bp_addr;
-
/* Pointers to the libthread_db functions. */
- td_err_e (*td_init_p) (void);
-
- td_err_e (*td_ta_new_p) (struct ps_prochandle * ps,
- td_thragent_t **ta);
- td_err_e (*td_ta_map_id2thr_p) (const td_thragent_t *ta, thread_t pt,
- td_thrhandle_t *__th);
- td_err_e (*td_ta_map_lwp2thr_p) (const td_thragent_t *ta,
- lwpid_t lwpid, td_thrhandle_t *th);
- td_err_e (*td_ta_thr_iter_p) (const td_thragent_t *ta,
- td_thr_iter_f *callback, void *cbdata_p,
- td_thr_state_e state, int ti_pri,
- sigset_t *ti_sigmask_p,
- unsigned int ti_user_flags);
- td_err_e (*td_ta_event_addr_p) (const td_thragent_t *ta,
- td_event_e event, td_notify_t *ptr);
- td_err_e (*td_ta_set_event_p) (const td_thragent_t *ta,
- td_thr_events_t *event);
- td_err_e (*td_ta_clear_event_p) (const td_thragent_t *ta,
- td_thr_events_t *event);
- td_err_e (*td_ta_event_getmsg_p) (const td_thragent_t *ta,
- td_event_msg_t *msg);
-
- td_err_e (*td_thr_validate_p) (const td_thrhandle_t *th);
- td_err_e (*td_thr_get_info_p) (const td_thrhandle_t *th,
- td_thrinfo_t *infop);
- td_err_e (*td_thr_event_enable_p) (const td_thrhandle_t *th,
- int event);
-
- td_err_e (*td_thr_tls_get_addr_p) (const td_thrhandle_t *th,
- psaddr_t map_address,
- size_t offset, psaddr_t *address);
- td_err_e (*td_thr_tlsbase_p) (const td_thrhandle_t *th,
- unsigned long int modid,
- psaddr_t *base);
+ td_init_ftype *td_init_p;
+ td_ta_new_ftype *td_ta_new_p;
+ td_ta_map_lwp2thr_ftype *td_ta_map_lwp2thr_p;
+ td_ta_thr_iter_ftype *td_ta_thr_iter_p;
+ td_thr_get_info_ftype *td_thr_get_info_p;
+ td_thr_tls_get_addr_ftype *td_thr_tls_get_addr_p;
+ td_thr_tlsbase_ftype *td_thr_tlsbase_p;
};
/* List of known processes using thread_db, and the required
static void check_thread_signals (void);
-static void record_thread (struct thread_db_info *info,
- struct thread_info *tp,
- ptid_t ptid, const td_thrhandle_t *th_p,
- const td_thrinfo_t *ti_p);
+static struct thread_info *record_thread
+ (struct thread_db_info *info, struct thread_info *tp,
+ ptid_t ptid, const td_thrhandle_t *th_p, const td_thrinfo_t *ti_p);
/* Add the current inferior to the list of processes using libpthread.
Return a pointer to the newly allocated object that was added to
static struct thread_db_info *
add_thread_db_info (void *handle)
{
- struct thread_db_info *info;
+ struct thread_db_info *info = XCNEW (struct thread_db_info);
- info = xcalloc (1, sizeof (*info));
info->pid = ptid_get_pid (inferior_ptid);
info->handle = handle;
xfree (info);
}
-/* Prototypes for local functions. */
-static int attach_thread (ptid_t ptid, const td_thrhandle_t *th_p,
- const td_thrinfo_t *ti_p);
-static void detach_thread (ptid_t ptid);
-\f
-
/* Use "struct private_thread_info" to cache thread state. This is
a substantial optimization. */
-struct private_thread_info
+struct thread_db_thread_info : public private_thread_info
{
/* Flag set when we see a TD_DEATH event for this thread. */
- unsigned int dying:1;
+ bool dying = false;
/* Cached thread state. */
- td_thrhandle_t th;
- thread_t tid;
+ td_thrhandle_t th {};
+ thread_t tid {};
};
-\f
-static char *
+static thread_db_thread_info *
+get_thread_db_thread_info (thread_info *thread)
+{
+ return static_cast<thread_db_thread_info *> (thread->priv.get ());
+}
+
+static const char *
thread_db_err_str (td_err_e err)
{
static char buf[64];
return buf;
}
}
-\f
-/* Return 1 if any threads have been registered. There may be none if
- the threading library is not fully initialized yet. */
-static int
-have_threads_callback (struct thread_info *thread, void *args)
-{
- int pid = * (int *) args;
-
- if (ptid_get_pid (thread->ptid) != pid)
- return 0;
-
- return thread->priv != NULL;
-}
-
-static int
-have_threads (ptid_t ptid)
-{
- int pid = ptid_get_pid (ptid);
-
- return iterate_over_threads (have_threads_callback, &pid) != NULL;
-}
-
-\f
/* Fetch the user-level thread id of PTID. */
-static void
+static struct thread_info *
thread_from_lwp (ptid_t ptid)
{
td_thrhandle_t th;
/* Fill the cache. */
tp = find_thread_ptid (ptid);
- record_thread (info, tp, ptid, &th, &ti);
+ return record_thread (info, tp, ptid, &th, &ti);
}
\f
int
thread_db_notice_clone (ptid_t parent, ptid_t child)
{
- td_thrhandle_t th;
- td_thrinfo_t ti;
- td_err_e err;
struct thread_db_info *info;
info = get_thread_db_info (ptid_get_pid (child));
return sym;
}
-static td_err_e
-enable_thread_event (int event, CORE_ADDR *bp)
-{
- td_notify_t notify;
- td_err_e err;
- struct thread_db_info *info;
-
- info = get_thread_db_info (ptid_get_pid (inferior_ptid));
-
- /* Access an lwp we know is stopped. */
- info->proc_handle.ptid = inferior_ptid;
-
- /* Get the breakpoint address for thread EVENT. */
- err = info->td_ta_event_addr_p (info->thread_agent, event, ¬ify);
- if (err != TD_OK)
- return err;
-
- /* Set up the breakpoint. */
- gdb_assert (exec_bfd);
- (*bp) = (gdbarch_convert_from_func_ptr_addr
- (target_gdbarch (),
- /* Do proper sign extension for the target. */
- (bfd_get_sign_extend_vma (exec_bfd) > 0
- ? (CORE_ADDR) (intptr_t) notify.u.bptaddr
- : (CORE_ADDR) (uintptr_t) notify.u.bptaddr),
- ¤t_target));
- create_thread_event_breakpoint (target_gdbarch (), *bp);
-
- return TD_OK;
-}
-
/* Verify inferior's '\0'-terminated symbol VER_SYMBOL starts with "%d.%d" and
return 1 if this version is lower (and not equal) to
VER_MAJOR_MIN.VER_MINOR_MIN. Return 0 in all other cases. */
return retval;
}
-static void
-enable_thread_event_reporting (void)
-{
- td_thr_events_t events;
- td_err_e err;
- struct thread_db_info *info;
-
- info = get_thread_db_info (ptid_get_pid (inferior_ptid));
-
- /* We cannot use the thread event reporting facility if these
- functions aren't available. */
- if (info->td_ta_event_addr_p == NULL
- || info->td_ta_set_event_p == NULL
- || info->td_ta_event_getmsg_p == NULL
- || info->td_thr_event_enable_p == NULL)
- return;
-
- /* Set the process wide mask saying which events we're interested in. */
- td_event_emptyset (&events);
- td_event_addset (&events, TD_CREATE);
-
- /* There is a bug fixed between linuxthreads 2.1.3 and 2.2 by
- commit 2e4581e4fba917f1779cd0a010a45698586c190a
- * manager.c (pthread_exited): Correctly report event as TD_REAP
- instead of TD_DEATH. Fix comments.
- where event reporting facility is broken for TD_DEATH events,
- so don't enable it if we have glibc but a lower version. */
- if (!inferior_has_bug ("__linuxthreads_version", 2, 2))
- td_event_addset (&events, TD_DEATH);
-
- err = info->td_ta_set_event_p (info->thread_agent, &events);
- if (err != TD_OK)
- {
- warning (_("Unable to set global thread event mask: %s"),
- thread_db_err_str (err));
- return;
- }
-
- /* Delete previous thread event breakpoints, if any. */
- remove_thread_event_breakpoints ();
- info->td_create_bp_addr = 0;
- info->td_death_bp_addr = 0;
-
- /* Set up the thread creation event. */
- err = enable_thread_event (TD_CREATE, &info->td_create_bp_addr);
- if (err != TD_OK)
- {
- warning (_("Unable to get location for thread creation breakpoint: %s"),
- thread_db_err_str (err));
- return;
- }
-
- /* Set up the thread death event. */
- err = enable_thread_event (TD_DEATH, &info->td_death_bp_addr);
- if (err != TD_OK)
- {
- warning (_("Unable to get location for thread death breakpoint: %s"),
- thread_db_err_str (err));
- return;
- }
-}
-
/* Similar as thread_db_find_new_threads_1, but try to silently ignore errors
if appropriate.
static int
thread_db_find_new_threads_silently (ptid_t ptid)
{
- volatile struct gdb_exception except;
- TRY_CATCH (except, RETURN_MASK_ERROR)
+ TRY
{
thread_db_find_new_threads_2 (ptid, 1);
}
- if (except.reason < 0)
+ CATCH (except, RETURN_MASK_ERROR)
{
if (libthread_db_debug)
exception_fprintf (gdb_stdlog, except,
return 1;
}
}
+ END_CATCH
+
return 0;
}
/* Initialize pointers to the dynamic library functions we will use.
Essential functions first. */
- info->td_init_p = verbose_dlsym (info->handle, "td_init");
- if (info->td_init_p == NULL)
- return 0;
+#define TDB_VERBOSE_DLSYM(info, func) \
+ info->func ## _p = (func ## _ftype *) verbose_dlsym (info->handle, #func)
+
+#define TDB_DLSYM(info, func) \
+ info->func ## _p = (func ## _ftype *) dlsym (info->handle, #func)
+
+#define CHK(a) \
+ do \
+ { \
+ if ((a) == NULL) \
+ return 0; \
+ } while (0)
+
+ CHK (TDB_VERBOSE_DLSYM (info, td_init));
err = info->td_init_p ();
if (err != TD_OK)
return 0;
}
- info->td_ta_new_p = verbose_dlsym (info->handle, "td_ta_new");
- if (info->td_ta_new_p == NULL)
- return 0;
+ CHK (TDB_VERBOSE_DLSYM (info, td_ta_new));
/* Initialize the structure that identifies the child process. */
info->proc_handle.ptid = inferior_ptid;
return 0;
}
- info->td_ta_map_id2thr_p = verbose_dlsym (info->handle, "td_ta_map_id2thr");
- if (info->td_ta_map_id2thr_p == NULL)
- return 0;
-
- info->td_ta_map_lwp2thr_p = verbose_dlsym (info->handle,
- "td_ta_map_lwp2thr");
- if (info->td_ta_map_lwp2thr_p == NULL)
- return 0;
-
- info->td_ta_thr_iter_p = verbose_dlsym (info->handle, "td_ta_thr_iter");
- if (info->td_ta_thr_iter_p == NULL)
- return 0;
-
- info->td_thr_validate_p = verbose_dlsym (info->handle, "td_thr_validate");
- if (info->td_thr_validate_p == NULL)
- return 0;
-
- info->td_thr_get_info_p = verbose_dlsym (info->handle, "td_thr_get_info");
- if (info->td_thr_get_info_p == NULL)
- return 0;
+ /* These are essential. */
+ CHK (TDB_VERBOSE_DLSYM (info, td_ta_map_lwp2thr));
+ CHK (TDB_VERBOSE_DLSYM (info, td_thr_get_info));
/* These are not essential. */
- info->td_ta_event_addr_p = dlsym (info->handle, "td_ta_event_addr");
- info->td_ta_set_event_p = dlsym (info->handle, "td_ta_set_event");
- info->td_ta_clear_event_p = dlsym (info->handle, "td_ta_clear_event");
- info->td_ta_event_getmsg_p = dlsym (info->handle, "td_ta_event_getmsg");
- info->td_thr_event_enable_p = dlsym (info->handle, "td_thr_event_enable");
- info->td_thr_tls_get_addr_p = dlsym (info->handle, "td_thr_tls_get_addr");
- info->td_thr_tlsbase_p = dlsym (info->handle, "td_thr_tlsbase");
+ TDB_DLSYM (info, td_thr_tls_get_addr);
+ TDB_DLSYM (info, td_thr_tlsbase);
/* It's best to avoid td_ta_thr_iter if possible. That walks data
structures in the inferior's address space that may be corrupted,
currently on core targets, as it uses ptrace directly. */
if (target_has_execution
&& linux_proc_task_list_dir_exists (ptid_get_pid (inferior_ptid)))
+ info->td_ta_thr_iter_p = NULL;
+ else
+ CHK (TDB_VERBOSE_DLSYM (info, td_ta_thr_iter));
+
+#undef TDB_VERBOSE_DLSYM
+#undef TDB_DLSYM
+#undef CHK
+
+ if (info->td_ta_thr_iter_p == NULL)
{
struct lwp_info *lp;
int pid = ptid_get_pid (inferior_ptid);
struct ui_file *file;
const char *library;
- library = dladdr_to_soname (*info->td_ta_new_p);
+ library = dladdr_to_soname ((const void *) *info->td_ta_new_p);
if (library == NULL)
library = LIBTHREAD_DB_SO;
if (thread_db_list->next == NULL)
push_target (&thread_db_ops);
- /* Enable event reporting, but not when debugging a core file. */
- if (target_has_execution && thread_db_use_events ())
- enable_thread_event_reporting ();
-
return 1;
}
/* Do not save system library name, that one is always trusted. */
if (strchr (library, '/') != NULL)
- info->filename = gdb_realpath (library);
+ info->filename = gdb_realpath (library).release ();
if (try_thread_db_load_1 (info))
return 1;
char *path, *cp;
int result;
const char *obj_name = objfile_name (obj);
+ int alloc_len;
if (obj_name[0] != '/')
{
return 0;
}
- path = xmalloc (strlen (obj_name) + (subdir ? strlen (subdir) + 1 : 0)
- + 1 + strlen (LIBTHREAD_DB_SO) + 1);
+ alloc_len = (strlen (obj_name)
+ + (subdir ? strlen (subdir) + 1 : 0)
+ + 1 + strlen (LIBTHREAD_DB_SO) + 1);
+ path = (char *) xmalloc (alloc_len);
cleanup = make_cleanup (xfree, path);
strcpy (path, obj_name);
if (!auto_load_thread_db)
return 0;
- path = xmalloc (dir_len + 1 + strlen (LIBTHREAD_DB_SO) + 1);
+ path = (char *) xmalloc (dir_len + 1 + strlen (LIBTHREAD_DB_SO) + 1);
cleanup = make_cleanup (xfree, path);
memcpy (path, dir, dir_len);
if (this_dir[pdir_len] == '/')
{
- subdir = xmalloc (strlen (this_dir));
+ subdir = (char *) xmalloc (strlen (this_dir));
make_cleanup (xfree, subdir);
strcpy (subdir, this_dir + pdir_len + 1);
}
return 0;
}
-static void
-disable_thread_event_reporting (struct thread_db_info *info)
-{
- if (info->td_ta_clear_event_p != NULL)
- {
- td_thr_events_t events;
-
- /* Set the process wide mask saying we aren't interested in any
- events anymore. */
- td_event_fillset (&events);
- info->td_ta_clear_event_p (info->thread_agent, &events);
- }
-
- info->td_create_bp_addr = 0;
- info->td_death_bp_addr = 0;
-}
-
static void
check_thread_signals (void)
{
child's thread list, we'll mistakenly think it has no threads
since the thread PID fields won't match the PID we give to
libthread_db. */
- char *our_pid_ns = linux_proc_pid_get_ns (getpid (), "pid");
- char *inferior_pid_ns = linux_proc_pid_get_ns (
- ptid_get_pid (inferior_ptid), "pid");
-
- if (our_pid_ns != NULL && inferior_pid_ns != NULL
- && strcmp (our_pid_ns, inferior_pid_ns) != 0)
+ if (!linux_ns_same (ptid_get_pid (inferior_ptid), LINUX_NS_PID))
{
warning (_ ("Target and debugger are in different PID "
"namespaces; thread lists and other data are "
- "likely unreliable"));
+ "likely unreliable. "
+ "Connect to gdbserver inside the container."));
}
-
- xfree (our_pid_ns);
- xfree (inferior_pid_ns);
}
}
from libthread_db thread state information. */
static void
-update_thread_state (struct private_thread_info *priv,
+update_thread_state (thread_db_thread_info *priv,
const td_thrinfo_t *ti_p)
{
priv->dying = (ti_p->ti_state == TD_THR_UNKNOWN
|| ti_p->ti_state == TD_THR_ZOMBIE);
}
-/* Attach to a new thread. This function is called when we receive a
- TD_CREATE event or when we iterate over all threads and find one
- that wasn't already in our list. Returns true on success. */
-
-static int
-attach_thread (ptid_t ptid, const td_thrhandle_t *th_p,
- const td_thrinfo_t *ti_p)
-{
- struct thread_info *tp;
- struct thread_db_info *info;
-
- /* If we're being called after a TD_CREATE event, we may already
- know about this thread. There are two ways this can happen. We
- may have iterated over all threads between the thread creation
- and the TD_CREATE event, for instance when the user has issued
- the `info threads' command before the SIGTRAP for hitting the
- thread creation breakpoint was reported. Alternatively, the
- thread may have exited and a new one been created with the same
- thread ID. In the first case we don't need to do anything; in
- the second case we should discard information about the dead
- thread and attach to the new one. */
- tp = find_thread_ptid (ptid);
- if (tp != NULL)
- {
- /* If tp->priv is NULL, then GDB is already attached to this
- thread, but we do not know anything about it. We can learn
- about it here. This can only happen if we have some other
- way besides libthread_db to notice new threads (i.e.
- PTRACE_EVENT_CLONE); assume the same mechanism notices thread
- exit, so this can not be a stale thread recreated with the
- same ID. */
- if (tp->priv != NULL)
- {
- if (!tp->priv->dying)
- return 0;
-
- delete_thread (ptid);
- tp = NULL;
- }
- }
-
- /* Under GNU/Linux, we have to attach to each and every thread. */
- if (target_has_execution
- && tp == NULL)
- {
- int res;
-
- res = lin_lwp_attach_lwp (ptid_build (ptid_get_pid (ptid),
- ti_p->ti_lid, 0));
- if (res < 0)
- {
- /* Error, stop iterating. */
- return 0;
- }
- else if (res > 0)
- {
- /* Pretend this thread doesn't exist yet, and keep
- iterating. */
- return 1;
- }
-
- /* Otherwise, we sucessfully attached to the thread. */
- }
-
- info = get_thread_db_info (ptid_get_pid (ptid));
- record_thread (info, tp, ptid, th_p, ti_p);
- return 1;
-}
-
/* Record a new thread in GDB's thread list. Creates the thread's
- private info. If TP is NULL, creates a new thread. Otherwise,
- uses TP. */
+ private info. If TP is NULL or TP is marked as having exited,
+ creates a new thread. Otherwise, uses TP. */
-static void
+static struct thread_info *
record_thread (struct thread_db_info *info,
struct thread_info *tp,
ptid_t ptid, const td_thrhandle_t *th_p,
const td_thrinfo_t *ti_p)
{
- td_err_e err;
- struct private_thread_info *priv;
- int new_thread = (tp == NULL);
-
/* A thread ID of zero may mean the thread library has not
initialized yet. Leave private == NULL until the thread library
has initialized. */
if (ti_p->ti_tid == 0)
- return;
+ return tp;
/* Construct the thread's private data. */
- priv = xmalloc (sizeof (struct private_thread_info));
- memset (priv, 0, sizeof (struct private_thread_info));
+ thread_db_thread_info *priv = new thread_db_thread_info;
priv->th = *th_p;
priv->tid = ti_p->ti_tid;
update_thread_state (priv, ti_p);
- /* Add the thread to GDB's thread list. */
- if (tp == NULL)
+ /* Add the thread to GDB's thread list. If we already know about a
+ thread with this PTID, but it's marked exited, then the kernel
+ reused the tid of an old thread. */
+ if (tp == NULL || tp->state == THREAD_EXITED)
tp = add_thread_with_info (ptid, priv);
else
- tp->priv = priv;
-
- /* Enable thread event reporting for this thread, except when
- debugging a core file. */
- if (target_has_execution && thread_db_use_events () && new_thread)
- {
- err = info->td_thr_event_enable_p (th_p, 1);
- if (err != TD_OK)
- error (_("Cannot enable thread event reporting for %s: %s"),
- target_pid_to_str (ptid), thread_db_err_str (err));
- }
+ tp->priv.reset (priv);
if (target_has_execution)
check_thread_signals ();
-}
-
-static void
-detach_thread (ptid_t ptid)
-{
- struct thread_info *thread_info;
- /* Don't delete the thread now, because it still reports as active
- until it has executed a few instructions after the event
- breakpoint - if we deleted it now, "info threads" would cause us
- to re-attach to it. Just mark it as having had a TD_DEATH
- event. This means that we won't delete it from our thread list
- until we notice that it's dead (via prune_threads), or until
- something re-uses its thread ID. We'll report the thread exit
- when the underlying LWP dies. */
- thread_info = find_thread_ptid (ptid);
- gdb_assert (thread_info != NULL && thread_info->priv != NULL);
- thread_info->priv->dying = 1;
+ return tp;
}
static void
info = get_thread_db_info (ptid_get_pid (inferior_ptid));
if (info)
- {
- if (target_has_execution && thread_db_use_events ())
- {
- disable_thread_event_reporting (info);
-
- /* Delete the old thread event breakpoints. Note that
- unlike when mourning, we can remove them here because
- there's still a live inferior to poke at. In any case,
- GDB will not try to insert anything in the inferior when
- removing a breakpoint. */
- remove_thread_event_breakpoints ();
- }
-
- delete_thread_db_info (ptid_get_pid (inferior_ptid));
- }
+ delete_thread_db_info (ptid_get_pid (inferior_ptid));
target_beneath->to_detach (target_beneath, args, from_tty);
unpush_target (&thread_db_ops);
}
-/* Check if PID is currently stopped at the location of a thread event
- breakpoint location. If it is, read the event message and act upon
- the event. */
-
-static void
-check_event (ptid_t ptid)
-{
- struct regcache *regcache = get_thread_regcache (ptid);
- struct gdbarch *gdbarch = get_regcache_arch (regcache);
- td_event_msg_t msg;
- td_thrinfo_t ti;
- td_err_e err;
- CORE_ADDR stop_pc;
- int loop = 0;
- struct thread_db_info *info;
-
- info = get_thread_db_info (ptid_get_pid (ptid));
-
- /* Bail out early if we're not at a thread event breakpoint. */
- stop_pc = regcache_read_pc (regcache);
- if (!target_supports_stopped_by_sw_breakpoint ())
- stop_pc -= gdbarch_decr_pc_after_break (gdbarch);
-
- if (stop_pc != info->td_create_bp_addr
- && stop_pc != info->td_death_bp_addr)
- return;
-
- /* Access an lwp we know is stopped. */
- info->proc_handle.ptid = ptid;
-
- /* If we have only looked at the first thread before libpthread was
- initialized, we may not know its thread ID yet. Make sure we do
- before we add another thread to the list. */
- if (!have_threads (ptid))
- thread_db_find_new_threads_1 (ptid);
-
- /* If we are at a create breakpoint, we do not know what new lwp
- was created and cannot specifically locate the event message for it.
- We have to call td_ta_event_getmsg() to get
- the latest message. Since we have no way of correlating whether
- the event message we get back corresponds to our breakpoint, we must
- loop and read all event messages, processing them appropriately.
- This guarantees we will process the correct message before continuing
- from the breakpoint.
-
- Currently, death events are not enabled. If they are enabled,
- the death event can use the td_thr_event_getmsg() interface to
- get the message specifically for that lwp and avoid looping
- below. */
-
- loop = 1;
-
- do
- {
- err = info->td_ta_event_getmsg_p (info->thread_agent, &msg);
- if (err != TD_OK)
- {
- if (err == TD_NOMSG)
- return;
-
- error (_("Cannot get thread event message: %s"),
- thread_db_err_str (err));
- }
-
- err = info->td_thr_get_info_p (msg.th_p, &ti);
- if (err != TD_OK)
- error (_("Cannot get thread info: %s"), thread_db_err_str (err));
-
- ptid = ptid_build (ptid_get_pid (ptid), ti.ti_lid, 0);
-
- switch (msg.event)
- {
- case TD_CREATE:
- /* Call attach_thread whether or not we already know about a
- thread with this thread ID. */
- attach_thread (ptid, msg.th_p, &ti);
-
- break;
-
- case TD_DEATH:
-
- if (!in_thread_list (ptid))
- error (_("Spurious thread death event."));
-
- detach_thread (ptid);
-
- break;
-
- default:
- error (_("Spurious thread event."));
- }
- }
- while (loop);
-}
-
static ptid_t
thread_db_wait (struct target_ops *ops,
ptid_t ptid, struct target_waitstatus *ourstatus,
ptid = beneath->to_wait (beneath, ptid, ourstatus, options);
- if (ourstatus->kind == TARGET_WAITKIND_IGNORE)
- return ptid;
-
- if (ourstatus->kind == TARGET_WAITKIND_EXITED
- || ourstatus->kind == TARGET_WAITKIND_SIGNALLED)
- return ptid;
+ switch (ourstatus->kind)
+ {
+ case TARGET_WAITKIND_IGNORE:
+ case TARGET_WAITKIND_EXITED:
+ case TARGET_WAITKIND_THREAD_EXITED:
+ case TARGET_WAITKIND_SIGNALLED:
+ return ptid;
+ }
info = get_thread_db_info (ptid_get_pid (ptid));
if (!thread_db_list)
unpush_target (&thread_db_ops);
- /* Thread event breakpoints are deleted by
- update_breakpoints_after_exec. */
-
return ptid;
}
- if (ourstatus->kind == TARGET_WAITKIND_STOPPED
- && ourstatus->value.sig == GDB_SIGNAL_TRAP)
- /* Check for a thread event. */
- check_event (ptid);
-
/* Fill in the thread's user-level thread id and status. */
thread_from_lwp (ptid);
target_beneath->to_mourn_inferior (target_beneath);
- /* Delete the old thread event breakpoints. Do this after mourning
- the inferior, so that we don't try to uninsert them. */
- remove_thread_event_breakpoints ();
-
/* Detach thread_db target ops. */
if (!thread_db_list)
unpush_target (ops);
td_err_e err;
ptid_t ptid;
struct thread_info *tp;
- struct callback_data *cb_data = data;
+ struct callback_data *cb_data = (struct callback_data *) data;
struct thread_db_info *info = cb_data->info;
err = info->td_thr_get_info_p (th_p, &ti);
if (libthread_db_debug)
fprintf_unfiltered (gdb_stdlog,
"thread_db: skipping exited and "
- "joined thread (0x%lx)\n", ti.ti_tid);
+ "joined thread (0x%lx)\n",
+ (unsigned long) ti.ti_tid);
return 0;
}
/* A thread ID of zero means that this is the main thread, but
glibc has not yet initialized thread-local storage and the
pthread library. We do not know what the thread's TID will
- be yet. Just enable event reporting and otherwise ignore
- it. */
+ be yet. */
/* In that case, we're not stopped in a fork syscall and don't
need this glibc bug workaround. */
info->need_stale_parent_threads_check = 0;
- if (target_has_execution && thread_db_use_events ())
- {
- err = info->td_thr_event_enable_p (th_p, 1);
- if (err != TD_OK)
- error (_("Cannot enable thread event reporting for LWP %d: %s"),
- (int) ti.ti_lid, thread_db_err_str (err));
- }
-
return 0;
}
ptid = ptid_build (info->pid, ti.ti_lid, 0);
tp = find_thread_ptid (ptid);
if (tp == NULL || tp->priv == NULL)
- {
- if (attach_thread (ptid, th_p, &ti))
- cb_data->new_threads += 1;
- else
- /* Problem attaching this thread; perhaps it exited before we
- could attach it?
- This could mean that the thread list inside glibc itself is in
- inconsistent state, and libthread_db could go on looping forever
- (observed with glibc-2.3.6). To prevent that, terminate
- iteration: thread_db_find_new_threads_2 will retry. */
- return 1;
- }
- else if (target_has_execution && !thread_db_use_events ())
- {
- /* Need to update this if not using the libthread_db events
- (particularly, the TD_DEATH event). */
- update_thread_state (tp->priv, &ti);
- }
+ record_thread (info, tp, ptid, th_p, &ti);
return 0;
}
find_new_threads_once (struct thread_db_info *info, int iteration,
td_err_e *errp)
{
- volatile struct gdb_exception except;
struct callback_data data;
td_err_e err = TD_ERR;
data.new_threads = 0;
/* See comment in thread_db_update_thread_list. */
- gdb_assert (!target_has_execution || thread_db_use_events ());
+ gdb_assert (info->td_ta_thr_iter_p != NULL);
- TRY_CATCH (except, RETURN_MASK_ERROR)
+ TRY
{
/* Iterate over all user-space threads to discover new threads. */
err = info->td_ta_thr_iter_p (info->thread_agent,
TD_SIGNO_MASK,
TD_THR_ANY_USER_FLAGS);
}
+ CATCH (except, RETURN_MASK_ERROR)
+ {
+ if (libthread_db_debug)
+ {
+ exception_fprintf (gdb_stdlog, except,
+ "Warning: find_new_threads_once: ");
+ }
+ }
+ END_CATCH
if (libthread_db_debug)
{
- if (except.reason < 0)
- exception_fprintf (gdb_stdlog, except,
- "Warning: find_new_threads_once: ");
-
fprintf_unfiltered (gdb_stdlog,
_("Found %d new threads in iteration %d.\n"),
data.new_threads, iteration);
thread_db_find_new_threads_2 (ptid, 0);
}
-static int
-update_thread_core (struct lwp_info *info, void *closure)
-{
- info->core = linux_common_core_of_thread (info->ptid);
- return 0;
-}
-
-/* Update the thread list using td_ta_thr_iter. */
+/* Implement the to_update_thread_list target method for this
+ target. */
static void
-thread_db_update_thread_list_td_ta_thr_iter (struct target_ops *ops)
+thread_db_update_thread_list (struct target_ops *ops)
{
struct thread_db_info *info;
struct inferior *inf;
if (thread == NULL || thread->executing)
continue;
+ /* It's best to avoid td_ta_thr_iter if possible. That walks
+ data structures in the inferior's address space that may be
+ corrupted, or, if the target is running, the list may change
+ while we walk it. In the latter case, it's possible that a
+ thread exits just at the exact time that causes GDB to get
+ stuck in an infinite loop. To avoid pausing all threads
+ whenever the core wants to refresh the thread list, we
+ instead use thread_from_lwp immediately when we see an LWP
+ stop. That uses thread_db entry points that do not walk
+ libpthread's thread list, so should be safe, as well as more
+ efficient. */
+ if (target_has_execution_1 (thread->ptid))
+ continue;
+
thread_db_find_new_threads_1 (thread->ptid);
}
-}
-
-/* Implement the to_update_thread_list target method for this
- target. */
-
-static void
-thread_db_update_thread_list (struct target_ops *ops)
-{
- /* It's best to avoid td_ta_thr_iter if possible. That walks data
- structures in the inferior's address space that may be corrupted,
- or, if the target is running, the list may change while we walk
- it. In the latter case, it's possible that a thread exits just
- at the exact time that causes GDB to get stuck in an infinite
- loop. To avoid pausing all threads whenever the core wants to
- refresh the thread list, if the kernel supports clone events
- (meaning we're always already attached to all LWPs), we use
- thread_from_lwp immediately when we see an LWP stop. That uses
- thread_db entry points that do not walk libpthread's thread list,
- so should be safe, as well as more efficient. */
- if (target_has_execution && !thread_db_use_events ())
- ops->beneath->to_update_thread_list (ops->beneath);
- else
- thread_db_update_thread_list_td_ta_thr_iter (ops);
- if (target_has_execution)
- iterate_over_lwps (minus_one_ptid /* iterate over all */,
- update_thread_core, NULL);
+ /* Give the beneath target a chance to do extra processing. */
+ ops->beneath->to_update_thread_list (ops->beneath);
}
-static char *
+static const char *
thread_db_pid_to_str (struct target_ops *ops, ptid_t ptid)
{
struct thread_info *thread_info = find_thread_ptid (ptid);
if (thread_info != NULL && thread_info->priv != NULL)
{
static char buf[64];
- thread_t tid;
+ thread_db_thread_info *priv = get_thread_db_thread_info (thread_info);
- tid = thread_info->priv->tid;
snprintf (buf, sizeof (buf), "Thread 0x%lx (LWP %ld)",
- tid, ptid_get_lwp (ptid));
+ (unsigned long) priv->tid, ptid_get_lwp (ptid));
return buf;
}
/* Return a string describing the state of the thread specified by
INFO. */
-static char *
+static const char *
thread_db_extra_thread_info (struct target_ops *self,
struct thread_info *info)
{
if (info->priv == NULL)
return NULL;
- if (info->priv->dying)
+ thread_db_thread_info *priv = get_thread_db_thread_info (info);
+
+ if (priv->dying)
return "Exiting";
return NULL;
}
+/* Return pointer to the thread_info struct which corresponds to
+ THREAD_HANDLE (having length HANDLE_LEN). */
+
+static struct thread_info *
+thread_db_thread_handle_to_thread_info (struct target_ops *ops,
+ const gdb_byte *thread_handle,
+ int handle_len,
+ struct inferior *inf)
+{
+ struct thread_info *tp;
+ thread_t handle_tid;
+
+ /* Thread handle sizes must match in order to proceed. We don't use an
+ assert here because the resulting internal error will cause GDB to
+ exit. This isn't necessarily an internal error due to the possibility
+ of garbage being passed as the thread handle via the python interface. */
+ if (handle_len != sizeof (handle_tid))
+ error (_("Thread handle size mismatch: %d vs %zu (from libthread_db)"),
+ handle_len, sizeof (handle_tid));
+
+ handle_tid = * (const thread_t *) thread_handle;
+
+ ALL_NON_EXITED_THREADS (tp)
+ {
+ thread_db_thread_info *priv = get_thread_db_thread_info (tp);
+
+ if (tp->inf == inf && priv != NULL && handle_tid == priv->tid)
+ return tp;
+ }
+
+ return NULL;
+}
+
/* Get the address of the thread local variable in load module LM which
is stored at OFFSET within the thread local storage for thread PTID. */
struct thread_info *thread_info;
struct target_ops *beneath;
- /* If we have not discovered any threads yet, check now. */
- if (!have_threads (ptid))
- thread_db_find_new_threads_1 (ptid);
-
/* Find the matching thread. */
thread_info = find_thread_ptid (ptid);
+ /* We may not have discovered the thread yet. */
+ if (thread_info != NULL && thread_info->priv == NULL)
+ thread_info = thread_from_lwp (ptid);
+
if (thread_info != NULL && thread_info->priv != NULL)
{
td_err_e err;
psaddr_t address;
- struct thread_db_info *info;
-
- info = get_thread_db_info (ptid_get_pid (ptid));
+ thread_db_info *info = get_thread_db_info (ptid_get_pid (ptid));
+ thread_db_thread_info *priv = get_thread_db_thread_info (thread_info);
/* Finally, get the address of the variable. */
if (lm != 0)
/* Note the cast through uintptr_t: this interface only works if
a target address fits in a psaddr_t, which is a host pointer.
So a 32-bit debugger can not access 64-bit TLS through this. */
- err = info->td_thr_tls_get_addr_p (&thread_info->priv->th,
+ err = info->td_thr_tls_get_addr_p (&priv->th,
(psaddr_t)(uintptr_t) lm,
offset, &address);
}
PR libc/16831 due to GDB PR threads/16954 LOAD_MODULE is also NULL.
The constant number 1 depends on GNU __libc_setup_tls
initialization of l_tls_modid to 1. */
- err = info->td_thr_tlsbase_p (&thread_info->priv->th,
- 1, &address);
+ err = info->td_thr_tlsbase_p (&priv->th, 1, &address);
address = (char *) address + offset;
}
/* Implement 'info auto-load libthread-db'. */
static void
-info_auto_load_libthread_db (char *args, int from_tty)
+info_auto_load_libthread_db (const char *args, int from_tty)
{
struct ui_out *uiout = current_uiout;
const char *cs = args ? args : "";
char *pids;
int i;
- cs = skip_spaces_const (cs);
+ cs = skip_spaces (cs);
if (*cs)
error (_("'info auto-load libthread-db' does not accept any parameters"));
if (info->filename != NULL)
info_count++;
- array = xmalloc (sizeof (*array) * info_count);
+ array = XNEWVEC (struct thread_db_info *, info_count);
back_to = make_cleanup (xfree, array);
info_count = 0;
if (i == 0 || strcmp (array[i - 1]->filename, array[i]->filename) != 0)
{
unique_filenames++;
- max_filename_len = max (max_filename_len,
- strlen (array[i]->filename));
+ max_filename_len = std::max (max_filename_len,
+ strlen (array[i]->filename));
if (i > 0)
{
pids_len -= strlen (", ");
- max_pids_len = max (max_pids_len, pids_len);
+ max_pids_len = std::max (max_pids_len, pids_len);
}
pids_len = 0;
}
if (i)
{
pids_len -= strlen (", ");
- max_pids_len = max (max_pids_len, pids_len);
+ max_pids_len = std::max (max_pids_len, pids_len);
}
/* Table header shifted right by preceding "libthread-db: " would not match
its columns. */
if (info_count > 0 && args == auto_load_info_scripts_pattern_nl)
- ui_out_text (uiout, "\n");
+ uiout->text ("\n");
- make_cleanup_ui_out_table_begin_end (uiout, 2, unique_filenames,
- "LinuxThreadDbTable");
+ {
+ ui_out_emit_table table_emitter (uiout, 2, unique_filenames,
+ "LinuxThreadDbTable");
- ui_out_table_header (uiout, max_filename_len, ui_left, "filename",
- "Filename");
- ui_out_table_header (uiout, pids_len, ui_left, "PIDs", "Pids");
- ui_out_table_body (uiout);
+ uiout->table_header (max_filename_len, ui_left, "filename", "Filename");
+ uiout->table_header (pids_len, ui_left, "PIDs", "Pids");
+ uiout->table_body ();
- pids = xmalloc (max_pids_len + 1);
- make_cleanup (xfree, pids);
+ pids = (char *) xmalloc (max_pids_len + 1);
+ make_cleanup (xfree, pids);
- /* Note I is incremented inside the cycle, not at its end. */
- for (i = 0; i < info_count;)
- {
- struct cleanup *chain = make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
- char *pids_end;
-
- info = array[i];
- ui_out_field_string (uiout, "filename", info->filename);
- pids_end = pids;
+ /* Note I is incremented inside the cycle, not at its end. */
+ for (i = 0; i < info_count;)
+ {
+ ui_out_emit_tuple tuple_emitter (uiout, NULL);
+ char *pids_end;
- while (i < info_count && strcmp (info->filename, array[i]->filename) == 0)
- {
- if (pids_end != pids)
- {
- *pids_end++ = ',';
- *pids_end++ = ' ';
- }
- pids_end += xsnprintf (pids_end, &pids[max_pids_len + 1] - pids_end,
- "%u", array[i]->pid);
- gdb_assert (pids_end < &pids[max_pids_len + 1]);
+ info = array[i];
+ uiout->field_string ("filename", info->filename);
+ pids_end = pids;
- i++;
- }
- *pids_end = '\0';
+ while (i < info_count && strcmp (info->filename,
+ array[i]->filename) == 0)
+ {
+ if (pids_end != pids)
+ {
+ *pids_end++ = ',';
+ *pids_end++ = ' ';
+ }
+ pids_end += xsnprintf (pids_end,
+ &pids[max_pids_len + 1] - pids_end,
+ "%u", array[i]->pid);
+ gdb_assert (pids_end < &pids[max_pids_len + 1]);
+
+ i++;
+ }
+ *pids_end = '\0';
- ui_out_field_string (uiout, "pids", pids);
+ uiout->field_string ("pids", pids);
- ui_out_text (uiout, "\n");
- do_cleanups (chain);
- }
+ uiout->text ("\n");
+ }
+ }
do_cleanups (back_to);
if (info_count == 0)
- ui_out_message (uiout, 0, _("No auto-loaded libthread-db.\n"));
+ uiout->message (_("No auto-loaded libthread-db.\n"));
}
static void
= thread_db_get_thread_local_address;
thread_db_ops.to_extra_thread_info = thread_db_extra_thread_info;
thread_db_ops.to_get_ada_task_ptid = thread_db_get_ada_task_ptid;
+ thread_db_ops.to_thread_handle_to_thread_info = thread_db_thread_handle_to_thread_info;
thread_db_ops.to_magic = OPS_MAGIC;
complete_target_initialization (&thread_db_ops);
}
-/* Provide a prototype to silence -Wmissing-prototypes. */
-extern initialize_file_ftype _initialize_thread_db;
-
void
_initialize_thread_db (void)
{
/* Defer loading of libthread_db.so until inferior is running.
This allows gdb to load correct libthread_db for a given
- executable -- there could be mutiple versions of glibc,
- compiled with LinuxThreads or NPTL, and until there is
- a running inferior, we can't tell which libthread_db is
- the correct one to load. */
+ executable -- there could be multiple versions of glibc,
+ and until there is a running inferior, we can't tell which
+ libthread_db is the correct one to load. */
libthread_db_search_path = xstrdup (LIBTHREAD_DB_SEARCH_PATH);
projects / deliverable / binutils-gdb.git / blobdiff