/* libthread_db assisted debugging support, generic parts.
- Copyright 1999, 2000, 2001, 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "target.h"
#include "regcache.h"
#include "solib-svr4.h"
+#include "gdbcore.h"
+#include "observer.h"
+#include "linux-nat.h"
+
+#include <signal.h>
#ifdef HAVE_GNU_LIBC_VERSION_H
#include <gnu/libc-version.h>
#define LIBTHREAD_DB_SO "libthread_db.so.1"
#endif
+/* GNU/Linux libthread_db support.
+
+ libthread_db is a library, provided along with libpthread.so, which
+ exposes the internals of the thread library to a debugger. It
+ allows GDB to find existing threads, new threads as they are
+ 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).
+
+ libthread_db-specific information is stored in the "private" field
+ of struct thread_info. When the field is NULL we do not yet have
+ information about the new thread; this could be temporary (created,
+ but the thread library's data structures do not reflect it yet)
+ or permanent (created using clone instead of pthread_create).
+
+ Process IDs managed by linux-thread-db.c match those used by
+ linux-nat.c: a common PID for all processes, an LWP ID for each
+ thread, and no TID. We save the TID in private. Keeping it out
+ of the ptid_t prevents thread IDs changing when libpthread is
+ loaded or unloaded. */
+
/* If we're running on GNU/Linux, we must explicitly attach to any new
threads. */
-/* FIXME: There is certainly some room for improvements:
- - Cache LWP ids.
- - Bypass libthread_db when fetching or storing registers for
- threads bound to a LWP. */
-
/* This module's target vector. */
static struct target_ops thread_db_ops;
-/* The target vector that we call for things this module can't handle. */
-static struct target_ops *target_beneath;
-
-/* Pointer to the next function on the objfile event chain. */
-static void (*target_new_objfile_chain) (struct objfile * objfile);
-
/* Non-zero if we're using this module's target vector. */
static int using_thread_db;
static td_err_e (*td_thr_validate_p) (const td_thrhandle_t *th);
static td_err_e (*td_thr_get_info_p) (const td_thrhandle_t *th,
td_thrinfo_t *infop);
-static td_err_e (*td_thr_getfpregs_p) (const td_thrhandle_t *th,
- gdb_prfpregset_t *regset);
-static td_err_e (*td_thr_getgregs_p) (const td_thrhandle_t *th,
- prgregset_t gregs);
-static td_err_e (*td_thr_setfpregs_p) (const td_thrhandle_t *th,
- const gdb_prfpregset_t *fpregs);
-static td_err_e (*td_thr_setgregs_p) (const td_thrhandle_t *th,
- prgregset_t gregs);
static td_err_e (*td_thr_event_enable_p) (const td_thrhandle_t *th,
int event);
static CORE_ADDR td_death_bp_addr;
/* Prototypes for local functions. */
-static void thread_db_find_new_threads (void);
+static void thread_db_find_new_threads_1 (void);
static void attach_thread (ptid_t ptid, const td_thrhandle_t *th_p,
- const td_thrinfo_t *ti_p, int verbose);
-static void detach_thread (ptid_t ptid, int verbose);
-\f
-
-/* Building process ids. */
-
-#define GET_PID(ptid) ptid_get_pid (ptid)
-#define GET_LWP(ptid) ptid_get_lwp (ptid)
-#define GET_THREAD(ptid) ptid_get_tid (ptid)
-
-#define is_lwp(ptid) (GET_LWP (ptid) != 0)
-#define is_thread(ptid) (GET_THREAD (ptid) != 0)
-
-#define BUILD_LWP(lwp, pid) ptid_build (pid, lwp, 0)
+ 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
unsigned int dying:1;
/* Cached thread state. */
- unsigned int th_valid:1;
- unsigned int ti_valid:1;
-
td_thrhandle_t th;
- td_thrinfo_t ti;
+ thread_t tid;
};
\f
return "only part of register set was written/read";
case TD_NOXREGS:
return "X register set not available for this thread";
+#ifdef THREAD_DB_HAS_TD_NOTALLOC
+ case TD_NOTALLOC:
+ return "thread has not yet allocated TLS for given module";
+#endif
+#ifdef THREAD_DB_HAS_TD_VERSION
+ case TD_VERSION:
+ return "versions of libpthread and libthread_db do not match";
+#endif
+#ifdef THREAD_DB_HAS_TD_NOTLS
+ case TD_NOTLS:
+ return "there is no TLS segment in the given module";
+#endif
default:
snprintf (buf, sizeof (buf), "unknown thread_db error '%d'", err);
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 char *
-thread_db_state_str (td_thr_state_e state)
+static int
+have_threads_callback (struct thread_info *thread, void *dummy)
{
- static char buf[64];
+ return thread->private != NULL;
+}
- switch (state)
- {
- case TD_THR_STOPPED:
- return "stopped by debugger";
- case TD_THR_RUN:
- return "runnable";
- case TD_THR_ACTIVE:
- return "active";
- case TD_THR_ZOMBIE:
- return "zombie";
- case TD_THR_SLEEP:
- return "sleeping";
- case TD_THR_STOPPED_ASLEEP:
- return "stopped by debugger AND blocked";
- default:
- snprintf (buf, sizeof (buf), "unknown thread_db state %d", state);
- return buf;
- }
+static int
+have_threads (void)
+{
+ return iterate_over_threads (have_threads_callback, NULL) != NULL;
}
-\f
+
/* A callback function for td_ta_thr_iter, which we use to map all
threads to LWPs.
thread_db_err_str (err));
/* Fill the cache. */
- thread_ptid = ptid_build (GET_PID (inferior_ptid), ti.ti_lid, ti.ti_tid);
+ thread_ptid = ptid_build (GET_PID (proc_handle.ptid), ti.ti_lid, 0);
thread_info = find_thread_pid (thread_ptid);
/* In the case of a zombie thread, don't continue. We don't want to
{
if (infop != NULL)
*(struct thread_info **) infop = thread_info;
- if (thread_info != NULL)
- {
- memcpy (&thread_info->private->th, thp, sizeof (*thp));
- thread_info->private->th_valid = 1;
- memcpy (&thread_info->private->ti, &ti, sizeof (ti));
- thread_info->private->ti_valid = 1;
- }
return TD_THR_ZOMBIE;
}
if (thread_info == NULL)
{
/* New thread. Attach to it now (why wait?). */
- attach_thread (thread_ptid, thp, &ti, 1);
+ if (!have_threads ())
+ thread_db_find_new_threads_1 ();
+ else
+ attach_thread (thread_ptid, thp, &ti);
thread_info = find_thread_pid (thread_ptid);
gdb_assert (thread_info != NULL);
}
- memcpy (&thread_info->private->th, thp, sizeof (*thp));
- thread_info->private->th_valid = 1;
- memcpy (&thread_info->private->ti, &ti, sizeof (ti));
- thread_info->private->ti_valid = 1;
-
if (infop != NULL)
*(struct thread_info **) infop = thread_info;
return 0;
}
-
-/* Accessor functions for the thread_db information, with caching. */
-
-static void
-thread_db_map_id2thr (struct thread_info *thread_info, int fatal)
-{
- td_err_e err;
-
- if (thread_info->private->th_valid)
- return;
-
- err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (thread_info->ptid),
- &thread_info->private->th);
- if (err != TD_OK)
- {
- if (fatal)
- error (_("Cannot find thread %ld: %s"),
- (long) GET_THREAD (thread_info->ptid),
- thread_db_err_str (err));
- }
- else
- thread_info->private->th_valid = 1;
-}
-
-static td_thrinfo_t *
-thread_db_get_info (struct thread_info *thread_info)
-{
- td_err_e err;
-
- if (thread_info->private->ti_valid)
- return &thread_info->private->ti;
-
- if (!thread_info->private->th_valid)
- thread_db_map_id2thr (thread_info, 1);
-
- err =
- td_thr_get_info_p (&thread_info->private->th, &thread_info->private->ti);
- if (err != TD_OK)
- error (_("thread_db_get_info: cannot get thread info: %s"),
- thread_db_err_str (err));
-
- thread_info->private->ti_valid = 1;
- return &thread_info->private->ti;
-}
\f
/* Convert between user-level thread ids and LWP ids. */
struct thread_info *thread_info;
ptid_t thread_ptid;
- if (GET_LWP (ptid) == 0)
- ptid = BUILD_LWP (GET_PID (ptid), GET_PID (ptid));
-
- gdb_assert (is_lwp (ptid));
+ /* This ptid comes from linux-nat.c, which should always fill in the
+ LWP. */
+ gdb_assert (GET_LWP (ptid) != 0);
+ /* Access an lwp we know is stopped. */
+ proc_handle.ptid = ptid;
err = td_ta_map_lwp2thr_p (thread_agent, GET_LWP (ptid), &th);
if (err != TD_OK)
error (_("Cannot find user-level thread for LWP %ld: %s"),
&& thread_info == NULL)
return pid_to_ptid (-1);
- gdb_assert (thread_info && thread_info->private->ti_valid);
-
- return ptid_build (GET_PID (ptid), GET_LWP (ptid),
- thread_info->private->ti.ti_tid);
-}
-
-static ptid_t
-lwp_from_thread (ptid_t ptid)
-{
- return BUILD_LWP (GET_LWP (ptid), GET_PID (ptid));
+ gdb_assert (ptid_get_tid (ptid) == 0);
+ return ptid;
}
\f
-void
-thread_db_init (struct target_ops *target)
+/* Attach to lwp PTID, doing whatever else is required to have this
+ LWP under the debugger's control --- e.g., enabling event
+ reporting. Returns true on success. */
+int
+thread_db_attach_lwp (ptid_t ptid)
{
- target_beneath = target;
+ td_thrhandle_t th;
+ td_thrinfo_t ti;
+ td_err_e err;
+
+ if (!using_thread_db)
+ return 0;
+
+ /* This ptid comes from linux-nat.c, which should always fill in the
+ LWP. */
+ gdb_assert (GET_LWP (ptid) != 0);
+
+ /* Access an lwp we know is stopped. */
+ 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 ())
+ thread_db_find_new_threads_1 ();
+
+ err = td_ta_map_lwp2thr_p (thread_agent, GET_LWP (ptid), &th);
+ if (err != TD_OK)
+ /* Cannot find user-level thread. */
+ return 0;
+
+ err = td_thr_get_info_p (&th, &ti);
+ if (err != TD_OK)
+ {
+ warning (_("Cannot get thread info: %s"), thread_db_err_str (err));
+ return 0;
+ }
+
+ attach_thread (ptid, &th, &ti);
+ return 1;
}
static void *
if (td_thr_get_info_p == NULL)
return 0;
- td_thr_getfpregs_p = verbose_dlsym (handle, "td_thr_getfpregs");
- if (td_thr_getfpregs_p == NULL)
- return 0;
-
- td_thr_getgregs_p = verbose_dlsym (handle, "td_thr_getgregs");
- if (td_thr_getgregs_p == NULL)
- return 0;
-
- td_thr_setfpregs_p = verbose_dlsym (handle, "td_thr_setfpregs");
- if (td_thr_setfpregs_p == NULL)
- return 0;
-
- td_thr_setgregs_p = verbose_dlsym (handle, "td_thr_setgregs");
- if (td_thr_setgregs_p == NULL)
- return 0;
-
/* Initialize the library. */
err = td_init_p ();
if (err != TD_OK)
td_notify_t notify;
td_err_e err;
+ /* Access an lwp we know is stopped. */
+ proc_handle.ptid = inferior_ptid;
+
/* Get the breakpoint address for thread EVENT. */
err = td_ta_event_addr_p (thread_agent, event, ¬ify);
if (err != TD_OK)
return err;
/* Set up the breakpoint. */
- (*bp) = gdbarch_convert_from_func_ptr_addr (current_gdbarch,
- (CORE_ADDR) notify.u.bptaddr,
- ¤t_target);
+ gdb_assert (exec_bfd);
+ (*bp) = (gdbarch_convert_from_func_ptr_addr
+ (current_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 ((*bp));
return TD_OK;
td_event_addset (&events, TD_CREATE);
#ifdef HAVE_GNU_LIBC_VERSION_H
- /* FIXME: kettenis/2000-04-23: The event reporting facility is
- broken for TD_DEATH events in glibc 2.1.3, so don't enable it for
- now. */
+ /* The event reporting facility is broken for TD_DEATH events in
+ glibc 2.1.3, so don't enable it if we have glibc but a lower
+ version. */
libc_version = gnu_get_libc_version ();
if (sscanf (libc_version, "%d.%d", &libc_major, &libc_minor) == 2
&& (libc_major > 2 || (libc_major == 2 && libc_minor > 1)))
#endif
}
-static void
-thread_db_new_objfile (struct objfile *objfile)
+/* Check whether thread_db is usable. This function is called when
+ an inferior is created (or otherwise acquired, e.g. attached to)
+ and when new shared libraries are loaded into a running process. */
+
+void
+check_for_thread_db (void)
{
td_err_e err;
+ static int already_loaded;
+
+ /* Do nothing if we couldn't load libthread_db.so.1. */
+ if (td_ta_new_p == NULL)
+ return;
/* First time through, report that libthread_db was successfuly
loaded. Can't print this in in thread_db_load as, at that stage,
- the interpreter and it's console haven't started. The real
- problem here is that libthread_db is loaded too early - it should
- only be loaded when there is a program to debug. */
- {
- static int dejavu;
- if (!dejavu)
- {
- Dl_info info;
- const char *library = NULL;
- /* Try dladdr. */
- if (dladdr ((*td_ta_new_p), &info) != 0)
- library = info.dli_fname;
- /* Try dlinfo? */
- if (library == NULL)
- /* Paranoid - don't let a NULL path slip through. */
- library = LIBTHREAD_DB_SO;
- printf_unfiltered (_("Using host libthread_db library \"%s\".\n"),
- library);
- dejavu = 1;
- }
- }
+ the interpreter and it's console haven't started. */
- /* Don't attempt to use thread_db on targets which can not run
- (core files). */
- if (objfile == NULL || !target_has_execution)
+ if (!already_loaded)
{
- /* All symbols have been discarded. If the thread_db target is
- active, deactivate it now. */
- if (using_thread_db)
- {
- gdb_assert (proc_handle.pid == 0);
- unpush_target (&thread_db_ops);
- using_thread_db = 0;
- }
+ Dl_info info;
+ const char *library = NULL;
+ if (dladdr ((*td_ta_new_p), &info) != 0)
+ library = info.dli_fname;
+
+ /* Try dlinfo? */
+
+ if (library == NULL)
+ /* Paranoid - don't let a NULL path slip through. */
+ library = LIBTHREAD_DB_SO;
- goto quit;
+ if (info_verbose)
+ printf_unfiltered (_("Using host libthread_db library \"%s\".\n"),
+ library);
+ already_loaded = 1;
}
if (using_thread_db)
/* Nothing to do. The thread library was already detected and the
target vector was already activated. */
- goto quit;
+ return;
- /* Initialize the structure that identifies the child process. Note
- that at this point there is no guarantee that we actually have a
- child process. */
- proc_handle.pid = GET_PID (inferior_ptid);
+ /* Don't attempt to use thread_db on targets which can not run
+ (executables not running yet, core files) for now. */
+ if (!target_has_execution)
+ return;
+
+ /* Don't attempt to use thread_db for remote targets. */
+ if (!target_can_run (¤t_target))
+ return;
+
+ /* Initialize the structure that identifies the child process. */
+ proc_handle.ptid = inferior_ptid;
/* Now attempt to open a connection to the thread library. */
err = td_ta_new_p (&proc_handle, &thread_agent);
using_thread_db = 1;
enable_thread_event_reporting ();
- thread_db_find_new_threads ();
+ thread_db_find_new_threads_1 ();
break;
default:
thread_db_err_str (err));
break;
}
+}
-quit:
- if (target_new_objfile_chain)
- target_new_objfile_chain (objfile);
+static void
+thread_db_new_objfile (struct objfile *objfile)
+{
+ if (objfile != NULL)
+ check_for_thread_db ();
}
/* Attach to a new thread. This function is called when we receive a
static void
attach_thread (ptid_t ptid, const td_thrhandle_t *th_p,
- const td_thrinfo_t *ti_p, int verbose)
+ const td_thrinfo_t *ti_p)
{
- struct thread_info *tp;
+ struct private_thread_info *private;
+ struct thread_info *tp = NULL;
td_err_e err;
/* If we're being called after a TD_CREATE event, we may already
tp = find_thread_pid (ptid);
gdb_assert (tp != NULL);
- if (!tp->private->dying)
- return;
+ /* If tp->private 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->private != NULL)
+ {
+ if (!tp->private->dying)
+ return;
- delete_thread (ptid);
+ delete_thread (ptid);
+ tp = NULL;
+ }
}
check_thread_signals ();
- /* Add the thread to GDB's thread list. */
- tp = add_thread (ptid);
- tp->private = xmalloc (sizeof (struct private_thread_info));
- memset (tp->private, 0, sizeof (struct private_thread_info));
-
- if (verbose)
- printf_unfiltered (_("[New %s]\n"), target_pid_to_str (ptid));
-
if (ti_p->ti_state == TD_THR_UNKNOWN || ti_p->ti_state == TD_THR_ZOMBIE)
return; /* A zombie thread -- do not attach. */
/* Under GNU/Linux, we have to attach to each and every thread. */
-#ifdef ATTACH_LWP
- ATTACH_LWP (BUILD_LWP (ti_p->ti_lid, GET_PID (ptid)), 0);
-#endif
+ if (tp == NULL
+ && lin_lwp_attach_lwp (BUILD_LWP (ti_p->ti_lid, GET_PID (ptid))) < 0)
+ return;
+
+ /* Construct the thread's private data. */
+ private = xmalloc (sizeof (struct private_thread_info));
+ memset (private, 0, sizeof (struct private_thread_info));
+
+ /* A thread ID of zero may mean the thread library has not initialized
+ yet. But we shouldn't even get here if that's the case. FIXME:
+ if we change GDB to always have at least one thread in the thread
+ list this will have to go somewhere else; maybe private == NULL
+ until the thread_db target claims it. */
+ gdb_assert (ti_p->ti_tid != 0);
+ private->th = *th_p;
+ private->tid = ti_p->ti_tid;
+
+ /* Add the thread to GDB's thread list. */
+ if (tp == NULL)
+ tp = add_thread_with_info (ptid, private);
+ else
+ tp->private = private;
/* Enable thread event reporting for this thread. */
err = td_thr_event_enable_p (th_p, 1);
}
static void
-thread_db_attach (char *args, int from_tty)
-{
- target_beneath->to_attach (args, from_tty);
-
- /* Destroy thread info; it's no longer valid. */
- init_thread_list ();
-
- /* The child process is now the actual multi-threaded
- program. Snatch its process ID... */
- proc_handle.pid = GET_PID (inferior_ptid);
-
- /* ...and perform the remaining initialization steps. */
- enable_thread_event_reporting ();
- thread_db_find_new_threads ();
-}
-
-static void
-detach_thread (ptid_t ptid, int verbose)
+detach_thread (ptid_t ptid)
{
struct thread_info *thread_info;
- if (verbose)
- printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (ptid));
-
/* 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. */
+ something re-uses its thread ID. We'll report the thread exit
+ when the underlying LWP dies. */
thread_info = find_thread_pid (ptid);
- gdb_assert (thread_info != NULL);
+ gdb_assert (thread_info != NULL && thread_info->private != NULL);
thread_info->private->dying = 1;
}
static void
-thread_db_detach (char *args, int from_tty)
+thread_db_detach (struct target_ops *ops, char *args, int from_tty)
{
- disable_thread_event_reporting ();
+ struct target_ops *target_beneath = find_target_beneath (ops);
- /* There's no need to save & restore inferior_ptid here, since the
- inferior is supposed to be survive this function call. */
- inferior_ptid = lwp_from_thread (inferior_ptid);
+ disable_thread_event_reporting ();
/* Forget about the child's process ID. We shouldn't need it
anymore. */
- proc_handle.pid = 0;
-
- target_beneath->to_detach (args, from_tty);
-}
-
-static int
-clear_lwpid_callback (struct thread_info *thread, void *dummy)
-{
- /* If we know that our thread implementation is 1-to-1, we could save
- a certain amount of information; it's not clear how much, so we
- are always conservative. */
+ proc_handle.ptid = null_ptid;
- thread->private->th_valid = 0;
- thread->private->ti_valid = 0;
-
- return 0;
-}
-
-static void
-thread_db_resume (ptid_t ptid, int step, enum target_signal signo)
-{
- struct cleanup *old_chain = save_inferior_ptid ();
-
- if (GET_PID (ptid) == -1)
- inferior_ptid = lwp_from_thread (inferior_ptid);
- else if (is_thread (ptid))
- ptid = lwp_from_thread (ptid);
-
- /* Clear cached data which may not be valid after the resume. */
- iterate_over_threads (clear_lwpid_callback, NULL);
-
- target_beneath->to_resume (ptid, step, signo);
+ /* Detach thread_db target ops. */
+ unpush_target (&thread_db_ops);
+ using_thread_db = 0;
- do_cleanups (old_chain);
+ target_beneath->to_detach (target_beneath, args, from_tty);
}
/* Check if PID is currently stopped at the location of a thread 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;
int loop = 0;
/* Bail out early if we're not at a thread event breakpoint. */
- stop_pc = read_pc_pid (ptid) - DECR_PC_AFTER_BREAK;
+ stop_pc = regcache_read_pc (regcache)
+ - gdbarch_decr_pc_after_break (gdbarch);
if (stop_pc != td_create_bp_addr && stop_pc != td_death_bp_addr)
return;
+ /* Access an lwp we know is stopped. */
+ 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 ())
+ thread_db_find_new_threads_1 ();
+
/* 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
if (err != TD_OK)
error (_("Cannot get thread info: %s"), thread_db_err_str (err));
- ptid = ptid_build (GET_PID (ptid), ti.ti_lid, ti.ti_tid);
+ ptid = ptid_build (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, 1);
+ attach_thread (ptid, msg.th_p, &ti);
break;
if (!in_thread_list (ptid))
error (_("Spurious thread death event."));
- detach_thread (ptid, 1);
+ detach_thread (ptid);
break;
}
static ptid_t
-thread_db_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
+thread_db_wait (struct target_ops *ops,
+ ptid_t ptid, struct target_waitstatus *ourstatus)
{
- extern ptid_t trap_ptid;
-
- if (GET_PID (ptid) != -1 && is_thread (ptid))
- ptid = lwp_from_thread (ptid);
+ struct target_ops *beneath = find_target_beneath (ops);
- ptid = target_beneath->to_wait (ptid, ourstatus);
+ ptid = beneath->to_wait (beneath, ptid, ourstatus);
- if (proc_handle.pid == 0)
- /* The current child process isn't the actual multi-threaded
- program yet, so don't try to do any special thread-specific
- post-processing and bail out early. */
+ if (ourstatus->kind == TARGET_WAITKIND_IGNORE)
return ptid;
- if (ourstatus->kind == TARGET_WAITKIND_EXITED)
- return pid_to_ptid (-1);
-
- if (ourstatus->kind == TARGET_WAITKIND_STOPPED
- && ourstatus->value.sig == TARGET_SIGNAL_TRAP)
- /* Check for a thread event. */
- check_event (ptid);
-
- if (!ptid_equal (trap_ptid, null_ptid))
- trap_ptid = thread_from_lwp (trap_ptid);
-
- /* Change the ptid back into the higher level PID + TID format.
- If the thread is dead and no longer on the thread list, we will
- get back a dead ptid. This can occur if the thread death event
- gets postponed by other simultaneous events. In such a case,
- we want to just ignore the event and continue on. */
- ptid = thread_from_lwp (ptid);
- if (GET_PID (ptid) == -1)
- ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
-
- return ptid;
-}
-
-static int
-thread_db_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
- struct mem_attrib *attrib, struct target_ops *target)
-{
- struct cleanup *old_chain = save_inferior_ptid ();
- int xfer;
+ if (ourstatus->kind == TARGET_WAITKIND_EXITED
+ || ourstatus->kind == TARGET_WAITKIND_SIGNALLED)
+ return ptid;
- if (is_thread (inferior_ptid))
+ if (ourstatus->kind == TARGET_WAITKIND_EXECD)
{
- /* FIXME: This seems to be necessary to make sure breakpoints
- are removed. */
- if (!target_thread_alive (inferior_ptid))
- inferior_ptid = pid_to_ptid (GET_PID (inferior_ptid));
- else
- inferior_ptid = lwp_from_thread (inferior_ptid);
- }
-
- xfer =
- target_beneath->deprecated_xfer_memory (memaddr, myaddr, len, write,
- attrib, target);
-
- do_cleanups (old_chain);
- return xfer;
-}
-
-static void
-thread_db_fetch_registers (int regno)
-{
- struct thread_info *thread_info;
- prgregset_t gregset;
- gdb_prfpregset_t fpregset;
- td_err_e err;
+ remove_thread_event_breakpoints ();
+ unpush_target (&thread_db_ops);
+ using_thread_db = 0;
- if (!is_thread (inferior_ptid))
- {
- /* Pass the request to the target beneath us. */
- target_beneath->to_fetch_registers (regno);
- return;
+ return ptid;
}
- thread_info = find_thread_pid (inferior_ptid);
- thread_db_map_id2thr (thread_info, 1);
-
- err = td_thr_getgregs_p (&thread_info->private->th, gregset);
- if (err != TD_OK)
- error (_("Cannot fetch general-purpose registers for thread %ld: %s"),
- (long) GET_THREAD (inferior_ptid), thread_db_err_str (err));
+ /* If we do not know about the main thread yet, this would be a good time to
+ find it. */
+ if (ourstatus->kind == TARGET_WAITKIND_STOPPED && !have_threads ())
+ thread_db_find_new_threads_1 ();
- err = td_thr_getfpregs_p (&thread_info->private->th, &fpregset);
- if (err != TD_OK)
- error (_("Cannot get floating-point registers for thread %ld: %s"),
- (long) GET_THREAD (inferior_ptid), thread_db_err_str (err));
-
- /* Note that we must call supply_gregset after calling the thread_db
- routines because the thread_db routines call ps_lgetgregs and
- friends which clobber GDB's register cache. */
- supply_gregset ((gdb_gregset_t *) gregset);
- supply_fpregset (&fpregset);
-}
-
-static void
-thread_db_store_registers (int regno)
-{
- prgregset_t gregset;
- gdb_prfpregset_t fpregset;
- td_err_e err;
- struct thread_info *thread_info;
-
- if (!is_thread (inferior_ptid))
- {
- /* Pass the request to the target beneath us. */
- target_beneath->to_store_registers (regno);
- return;
- }
-
- thread_info = find_thread_pid (inferior_ptid);
- thread_db_map_id2thr (thread_info, 1);
+ if (ourstatus->kind == TARGET_WAITKIND_STOPPED
+ && ourstatus->value.sig == TARGET_SIGNAL_TRAP)
+ /* Check for a thread event. */
+ check_event (ptid);
- if (regno != -1)
+ if (have_threads ())
{
- char raw[MAX_REGISTER_SIZE];
-
- deprecated_read_register_gen (regno, raw);
- thread_db_fetch_registers (-1);
- regcache_raw_supply (current_regcache, regno, raw);
+ /* Change ptids back into the higher level PID + TID format. If
+ the thread is dead and no longer on the thread list, we will
+ get back a dead ptid. This can occur if the thread death
+ event gets postponed by other simultaneous events. In such a
+ case, we want to just ignore the event and continue on. */
+
+ ptid = thread_from_lwp (ptid);
+ if (GET_PID (ptid) == -1)
+ ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
}
- fill_gregset ((gdb_gregset_t *) gregset, -1);
- fill_fpregset (&fpregset, -1);
-
- err = td_thr_setgregs_p (&thread_info->private->th, gregset);
- if (err != TD_OK)
- error (_("Cannot store general-purpose registers for thread %ld: %s"),
- (long) GET_THREAD (inferior_ptid), thread_db_err_str (err));
- err = td_thr_setfpregs_p (&thread_info->private->th, &fpregset);
- if (err != TD_OK)
- error (_("Cannot store floating-point registers for thread %ld: %s"),
- (long) GET_THREAD (inferior_ptid), thread_db_err_str (err));
-}
-
-static void
-thread_db_kill (void)
-{
- /* There's no need to save & restore inferior_ptid here, since the
- inferior isn't supposed to survive this function call. */
- inferior_ptid = lwp_from_thread (inferior_ptid);
- target_beneath->to_kill ();
-}
-
-static void
-thread_db_create_inferior (char *exec_file, char *allargs, char **env,
- int from_tty)
-{
- unpush_target (&thread_db_ops);
- using_thread_db = 0;
- target_beneath->to_create_inferior (exec_file, allargs, env, from_tty);
-}
-
-static void
-thread_db_post_startup_inferior (ptid_t ptid)
-{
- if (proc_handle.pid == 0)
- {
- /* The child process is now the actual multi-threaded
- program. Snatch its process ID... */
- proc_handle.pid = GET_PID (ptid);
-
- /* ...and perform the remaining initialization steps. */
- enable_thread_event_reporting ();
- thread_db_find_new_threads ();
- }
+ return ptid;
}
static void
-thread_db_mourn_inferior (void)
+thread_db_mourn_inferior (struct target_ops *ops)
{
- remove_thread_event_breakpoints ();
+ struct target_ops *target_beneath = find_target_beneath (ops);
/* Forget about the child's process ID. We shouldn't need it
anymore. */
- proc_handle.pid = 0;
+ proc_handle.ptid = null_ptid;
+
+ target_beneath->to_mourn_inferior (target_beneath);
- target_beneath->to_mourn_inferior ();
+ /* 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. */
- unpush_target (&thread_db_ops);
+ unpush_target (ops);
using_thread_db = 0;
}
static int
-thread_db_thread_alive (ptid_t ptid)
-{
- td_thrhandle_t th;
- td_err_e err;
-
- if (is_thread (ptid))
- {
- struct thread_info *thread_info;
- thread_info = find_thread_pid (ptid);
-
- thread_db_map_id2thr (thread_info, 0);
- if (!thread_info->private->th_valid)
- return 0;
-
- err = td_thr_validate_p (&thread_info->private->th);
- if (err != TD_OK)
- return 0;
-
- if (!thread_info->private->ti_valid)
- {
- err =
- td_thr_get_info_p (&thread_info->private->th,
- &thread_info->private->ti);
- if (err != TD_OK)
- return 0;
- thread_info->private->ti_valid = 1;
- }
-
- if (thread_info->private->ti.ti_state == TD_THR_UNKNOWN
- || thread_info->private->ti.ti_state == TD_THR_ZOMBIE)
- return 0; /* A zombie thread. */
-
- return 1;
- }
-
- if (target_beneath->to_thread_alive)
- return target_beneath->to_thread_alive (ptid);
-
- return 0;
-}
-
-static int
find_new_threads_callback (const td_thrhandle_t *th_p, void *data)
{
td_thrinfo_t ti;
td_err_e err;
ptid_t ptid;
+ struct thread_info *tp;
err = td_thr_get_info_p (th_p, &ti);
if (err != TD_OK)
if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE)
return 0; /* A zombie -- ignore. */
- ptid = ptid_build (GET_PID (inferior_ptid), ti.ti_lid, ti.ti_tid);
+ ptid = ptid_build (GET_PID (proc_handle.ptid), ti.ti_lid, 0);
- if (!in_thread_list (ptid))
- attach_thread (ptid, th_p, &ti, 1);
+ if (ti.ti_tid == 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. */
+
+ err = 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));
+
+ return 0;
+ }
+
+ tp = find_thread_pid (ptid);
+ if (tp == NULL || tp->private == NULL)
+ attach_thread (ptid, th_p, &ti);
return 0;
}
+/* Search for new threads, accessing memory through stopped thread
+ PTID. */
+
static void
-thread_db_find_new_threads (void)
+thread_db_find_new_threads_1 (void)
{
td_err_e err;
+ struct lwp_info *lp;
+ ptid_t ptid;
+
+ /* In linux, we can only read memory through a stopped lwp. */
+ ALL_LWPS (lp, ptid)
+ if (lp->stopped)
+ break;
+
+ if (!lp)
+ /* There is no stopped thread. Bail out. */
+ return;
+ /* Access an lwp we know is stopped. */
+ proc_handle.ptid = ptid;
/* Iterate over all user-space threads to discover new threads. */
err = td_ta_thr_iter_p (thread_agent, find_new_threads_callback, NULL,
TD_THR_ANY_STATE, TD_THR_LOWEST_PRIORITY,
error (_("Cannot find new threads: %s"), thread_db_err_str (err));
}
+static void
+thread_db_find_new_threads (struct target_ops *ops)
+{
+ thread_db_find_new_threads_1 ();
+}
+
static char *
-thread_db_pid_to_str (ptid_t ptid)
+thread_db_pid_to_str (struct target_ops *ops, ptid_t ptid)
{
- if (is_thread (ptid))
+ struct thread_info *thread_info = find_thread_pid (ptid);
+ struct target_ops *beneath;
+
+ if (thread_info != NULL && thread_info->private != NULL)
{
static char buf[64];
- td_thrinfo_t *ti_p;
- td_err_e err;
- struct thread_info *thread_info;
+ thread_t tid;
+ tid = thread_info->private->tid;
thread_info = find_thread_pid (ptid);
- thread_db_map_id2thr (thread_info, 0);
- if (!thread_info->private->th_valid)
- {
- snprintf (buf, sizeof (buf), "Thread %ld (Missing)",
- GET_THREAD (ptid));
- return buf;
- }
-
- ti_p = thread_db_get_info (thread_info);
-
- if (ti_p->ti_state == TD_THR_ACTIVE && ti_p->ti_lid != 0)
- {
- snprintf (buf, sizeof (buf), "Thread %ld (LWP %d)",
- (long) ti_p->ti_tid, ti_p->ti_lid);
- }
- else
- {
- snprintf (buf, sizeof (buf), "Thread %ld (%s)",
- (long) ti_p->ti_tid,
- thread_db_state_str (ti_p->ti_state));
- }
+ snprintf (buf, sizeof (buf), "Thread 0x%lx (LWP %ld)",
+ tid, GET_LWP (ptid));
return buf;
}
- if (target_beneath->to_pid_to_str (ptid))
- return target_beneath->to_pid_to_str (ptid);
+ beneath = find_target_beneath (ops);
+ if (beneath->to_pid_to_str (beneath, ptid))
+ return beneath->to_pid_to_str (beneath, ptid);
return normal_pid_to_str (ptid);
}
-/* Get the address of the thread local variable in OBJFILE which is
- stored at OFFSET within the thread local storage for thread PTID. */
+/* Return a string describing the state of the thread specified by
+ INFO. */
+
+static char *
+thread_db_extra_thread_info (struct thread_info *info)
+{
+ if (info->private == NULL)
+ return NULL;
+
+ if (info->private->dying)
+ return "Exiting";
+
+ 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. */
static CORE_ADDR
-thread_db_get_thread_local_address (ptid_t ptid, struct objfile *objfile,
+thread_db_get_thread_local_address (struct target_ops *ops,
+ ptid_t ptid,
+ CORE_ADDR lm,
CORE_ADDR offset)
{
- if (is_thread (ptid))
+ struct thread_info *thread_info;
+ struct target_ops *beneath;
+
+ /* If we have not discovered any threads yet, check now. */
+ if (!have_threads ())
+ thread_db_find_new_threads_1 ();
+
+ /* Find the matching thread. */
+ thread_info = find_thread_pid (ptid);
+
+ if (thread_info != NULL && thread_info->private != NULL)
{
td_err_e err;
void *address;
- CORE_ADDR lm;
- struct thread_info *thread_info;
/* glibc doesn't provide the needed interface. */
if (!td_thr_tls_get_addr_p)
- {
- struct exception e
- = { RETURN_ERROR, TLS_NO_LIBRARY_SUPPORT_ERROR, 0 };
-
- throw_exception (e);
- }
+ throw_error (TLS_NO_LIBRARY_SUPPORT_ERROR,
+ _("No TLS library support"));
- /* Get the address of the link map for this objfile. */
- lm = svr4_fetch_objfile_link_map (objfile);
-
- /* Whoops, we couldn't find one. Bail out. */
- if (!lm)
- {
- struct exception e
- = { RETURN_ERROR, TLS_LOAD_MODULE_NOT_FOUND_ERROR, 0 };
-
- throw_exception (e);
- }
-
- /* Get info about the thread. */
- thread_info = find_thread_pid (ptid);
- thread_db_map_id2thr (thread_info, 1);
+ /* Caller should have verified that lm != 0. */
+ gdb_assert (lm != 0);
/* Finally, get the address of the variable. */
- err = td_thr_tls_get_addr_p (&thread_info->private->th, (void *) lm,
+ err = td_thr_tls_get_addr_p (&thread_info->private->th,
+ (void *)(size_t) lm,
offset, &address);
#ifdef THREAD_DB_HAS_TD_NOTALLOC
/* The memory hasn't been allocated, yet. */
if (err == TD_NOTALLOC)
- {
/* Now, if libthread_db provided the initialization image's
address, we *could* try to build a non-lvalue value from
the initialization image. */
-
- struct exception e
- = { RETURN_ERROR, TLS_NOT_ALLOCATED_YET_ERROR, 0 };
-
- throw_exception (e);
- }
+ throw_error (TLS_NOT_ALLOCATED_YET_ERROR,
+ _("TLS not allocated yet"));
#endif
/* Something else went wrong. */
if (err != TD_OK)
- {
- struct exception e
- = { RETURN_ERROR, TLS_GENERIC_ERROR, thread_db_err_str (err) };
-
- throw_exception (e);
- }
+ throw_error (TLS_GENERIC_ERROR,
+ (("%s")), thread_db_err_str (err));
/* Cast assuming host == target. Joy. */
- return (CORE_ADDR) address;
+ /* Do proper sign extension for the target. */
+ gdb_assert (exec_bfd);
+ return (bfd_get_sign_extend_vma (exec_bfd) > 0
+ ? (CORE_ADDR) (intptr_t) address
+ : (CORE_ADDR) (uintptr_t) address);
}
- if (target_beneath->to_get_thread_local_address)
- return target_beneath->to_get_thread_local_address (ptid, objfile, offset);
+ beneath = find_target_beneath (ops);
+ if (beneath->to_get_thread_local_address)
+ return beneath->to_get_thread_local_address (beneath, ptid, lm, offset);
else
- {
- struct exception e
- = { RETURN_ERROR, TLS_GENERIC_ERROR,
- "TLS not supported on this target" };
+ throw_error (TLS_GENERIC_ERROR,
+ _("TLS not supported on this target"));
+}
- throw_exception (e);
- }
+/* Callback routine used to find a thread based on the TID part of
+ its PTID. */
+
+static int
+thread_db_find_thread_from_tid (struct thread_info *thread, void *data)
+{
+ long *tid = (long *) data;
+
+ if (thread->private->tid == *tid)
+ return 1;
+
+ return 0;
+}
+
+/* Implement the to_get_ada_task_ptid target method for this target. */
+
+static ptid_t
+thread_db_get_ada_task_ptid (long lwp, long thread)
+{
+ struct thread_info *thread_info;
+
+ thread_db_find_new_threads_1 ();
+ thread_info = iterate_over_threads (thread_db_find_thread_from_tid, &thread);
+
+ gdb_assert (thread_info != NULL);
+
+ return (thread_info->ptid);
}
static void
thread_db_ops.to_shortname = "multi-thread";
thread_db_ops.to_longname = "multi-threaded child process.";
thread_db_ops.to_doc = "Threads and pthreads support.";
- thread_db_ops.to_attach = thread_db_attach;
thread_db_ops.to_detach = thread_db_detach;
- thread_db_ops.to_resume = thread_db_resume;
thread_db_ops.to_wait = thread_db_wait;
- thread_db_ops.to_fetch_registers = thread_db_fetch_registers;
- thread_db_ops.to_store_registers = thread_db_store_registers;
- thread_db_ops.deprecated_xfer_memory = thread_db_xfer_memory;
- thread_db_ops.to_kill = thread_db_kill;
- thread_db_ops.to_create_inferior = thread_db_create_inferior;
- thread_db_ops.to_post_startup_inferior = thread_db_post_startup_inferior;
thread_db_ops.to_mourn_inferior = thread_db_mourn_inferior;
- thread_db_ops.to_thread_alive = thread_db_thread_alive;
thread_db_ops.to_find_new_threads = thread_db_find_new_threads;
thread_db_ops.to_pid_to_str = thread_db_pid_to_str;
thread_db_ops.to_stratum = thread_stratum;
thread_db_ops.to_has_thread_control = tc_schedlock;
thread_db_ops.to_get_thread_local_address
= 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_magic = OPS_MAGIC;
}
+/* Provide a prototype to silence -Wmissing-prototypes. */
+extern initialize_file_ftype _initialize_thread_db;
+
void
_initialize_thread_db (void)
{
add_target (&thread_db_ops);
/* Add ourselves to objfile event chain. */
- target_new_objfile_chain = deprecated_target_new_objfile_hook;
- deprecated_target_new_objfile_hook = thread_db_new_objfile;
+ observer_attach_new_objfile (thread_db_new_objfile);
}
}
projects / external / binutils.git / blobdiff