2012-07-20 Pedro Alves <palves@redhat.com>
+ PR threads/11692
+ PR gdb/12203
+
+ * infrun.c (handle_inferior_event) <new thread>: Don't special
+ case minus_one_ptid.
+ <TARGET_WAITKIND_SPURIOUS>: Ditto.
+ * linux-thread-db.c (thread_get_info_callback): Don't return early
+ if the thread is zombie.
+ (thread_from_lwp): Change return type to void. Rewrite stale
+ comment.
+ (attach_thread): Don't return early if the thread is zombie,
+ instead set its "dying" flag.
+ (thread_db_wait): Don't return TARGET_WAITKIND_SPURIOUS anymore.
+ (find_new_threads_callback): Don't return early if the thread is
+ zombie.
+
+2012-07-20 Pedro Alves <palves@redhat.com>
+
* linux-nat.c (linux_nat_wait): Dump the passed in target options.
* target.c (target_wait): Likewise.
(str_comma_list_concat_elem, do_option, target_options_to_string):
}
if (ecs->ws.kind != TARGET_WAITKIND_EXITED
- && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
- && !ptid_equal (ecs->ptid, minus_one_ptid))
+ && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
{
ecs->event_thread = find_thread_ptid (ecs->ptid);
/* If it's a new thread, add it to the thread database. */
case TARGET_WAITKIND_SPURIOUS:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
- if (!ptid_equal (ecs->ptid, inferior_ptid)
- && !ptid_equal (ecs->ptid, minus_one_ptid))
+ if (!ptid_equal (ecs->ptid, inferior_ptid))
context_switch (ecs->ptid);
resume (0, GDB_SIGNAL_0);
prepare_to_wait (ecs);
thread_ptid = ptid_build (info->pid, ti.ti_lid, 0);
inout->thread_info = find_thread_ptid (thread_ptid);
- /* In the case of a zombie thread, don't continue. We don't want to
- attach to it thinking it is a new thread. */
- if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE)
- return TD_THR_ZOMBIE;
-
if (inout->thread_info == NULL)
{
/* New thread. Attach to it now (why wait?). */
return 0;
}
\f
-/* Convert between user-level thread ids and LWP ids. */
+/* Fetch the user-level thread id of PTID. */
-static ptid_t
+static void
thread_from_lwp (ptid_t ptid)
{
td_thrhandle_t th;
error (_("Cannot find user-level thread for LWP %ld: %s"),
GET_LWP (ptid), thread_db_err_str (err));
- /* Fetch the thread info. If we get back TD_THR_ZOMBIE, then the
- event thread has already died. If another gdb interface has called
- thread_alive() previously, the thread won't be found on the thread list
- anymore. In that case, we don't want to process this ptid anymore
- to avoid the possibility of later treating it as a newly
- discovered thread id that we should add to the list. Thus,
- we return a -1 ptid which is also how the thread list marks a
- dead thread. */
+ /* Long-winded way of fetching the thread info. */
io.thread_db_info = info;
io.thread_info = NULL;
- if (thread_get_info_callback (&th, &io) == TD_THR_ZOMBIE
- && io.thread_info == NULL)
- return minus_one_ptid;
-
- gdb_assert (ptid_get_tid (ptid) == 0);
- return ptid;
+ thread_get_info_callback (&th, &io);
}
\f
if (target_has_execution)
check_thread_signals ();
- if (ti_p->ti_state == TD_THR_UNKNOWN || ti_p->ti_state == TD_THR_ZOMBIE)
- return 0; /* A zombie thread -- do not attach. */
-
/* Under GNU/Linux, we have to attach to each and every thread. */
if (target_has_execution
&& tp == NULL)
gdb_assert (ti_p->ti_tid != 0);
private->th = *th_p;
private->tid = ti_p->ti_tid;
+ if (ti_p->ti_state == TD_THR_UNKNOWN || ti_p->ti_state == TD_THR_ZOMBIE)
+ private->dying = 1;
/* Add the thread to GDB's thread list. */
if (tp == NULL)
if (have_threads (ptid))
{
- /* 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 in the thread's user-level thread id. */
+ thread_from_lwp (ptid);
}
return ptid;
error (_("find_new_threads_callback: cannot get thread info: %s"),
thread_db_err_str (err));
- if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE)
- return 0; /* A zombie -- ignore. */
-
if (ti.ti_tid == 0)
{
/* A thread ID of zero means that this is the main thread, but
+2012-07-20 Pedro Alves <palves@redhat.com>
+
+ PR threads/11692
+ PR gdb/12203
+
+ * gdb.threads/create-fail.c: New file.
+ * gdb.threads/create-fail.exp: New file.
+
2012-07-19 Pedro Alves <palves@redhat.com>
* config/monitor.exp (gdb_load): Remove redundant ';' in for loop.
--- /dev/null
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2012 Free Software Foundation, Inc.
+
+ 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 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ 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, see <http://www.gnu.org/licenses/>. */
+
+#define _GNU_SOURCE
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sched.h>
+#include <errno.h>
+#include <string.h>
+#include <assert.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <dirent.h>
+#include <assert.h>
+
+/* Count the number of tasks/threads in the PID thread group. */
+
+static int
+count_tasks (pid_t pid)
+{
+ char path[100];
+ int count;
+ DIR *d;
+
+ snprintf (path, sizeof (path), "/proc/%d/task/", (int) pid);
+ d = opendir (path);
+ if (d == NULL)
+ return -1;
+
+ for (count = 0; readdir (d) != NULL; count++)
+ ;
+ closedir (d);
+
+ /* Account for '.' and '..'. */
+ assert (count > 2);
+ return count - 2;
+}
+
+pthread_attr_t attr[CPU_SETSIZE];
+pthread_t thr[CPU_SETSIZE];
+
+static void *
+mythread (void *_arg)
+{
+ return NULL;
+}
+
+int
+main ()
+{
+ int i;
+
+ for (i = 0; i < CPU_SETSIZE; i++)
+ {
+ cpu_set_t set;
+ int ret;
+
+ pthread_attr_init (&attr[i]);
+ CPU_ZERO_S (sizeof (set), &set);
+ CPU_SET_S (i, sizeof (set), &set);
+
+ ret = pthread_attr_setaffinity_np (&attr[i], sizeof (set), &set);
+ if (ret != 0)
+ {
+ fprintf (stderr, "set_affinity: %d: %s\n", ret, strerror (ret));
+ exit (3);
+ }
+ ret = pthread_create (&thr[i], &attr[i], mythread, NULL);
+ /* Should fail with EINVAL at some point. */
+ if (ret != 0)
+ {
+ unsigned long t;
+
+ fprintf (stderr, "pthread_create: %d: %s\n", ret, strerror (ret));
+
+ /* Wait for all threads to exit. pthread_create spawns a
+ clone thread even in the failing case, as it can only try
+ to set the affinity after creating the thread. That new
+ thread is immediately canceled (because setting the
+ affinity fails), by killing it with a SIGCANCEL signal,
+ which may end up in pthread_cancel/unwind paths, which
+ may trigger a libgcc_s.so load, making the thread hit the
+ solib-event breakpoint. Now, if we would let the program
+ exit without waiting, sometimes it would happen that the
+ inferior exits just while we're handling the solib-event,
+ resulting in errors being thrown due to failing ptrace
+ call fails (with ESCHR), breaking the test. */
+ t = 16;
+ while (count_tasks (getpid ()) > 1)
+ {
+ usleep (t);
+
+ if (t < 256)
+ t *= 2;
+ }
+
+ /* Normal exit, because this is what we are expecting. */
+ exit (0);
+ }
+ }
+
+ /* Should not normally be reached. */
+ exit (1);
+}
--- /dev/null
+# Copyright (C) 2012 Free Software Foundation, Inc.
+
+# 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 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# 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, see <http://www.gnu.org/licenses/>.
+
+# On GNU/Linux, a creating a thread bound to an unexisting cpu spawns
+# the clone child thread for a bit, which is then immediately
+# cancelled. The spawned child may trigger a dlopen (for libgcc_s)
+# while being cancelled, which results in a trap being reported to
+# GDB, for a thread that libthread_db considers to be TD_THR_ZOMBIE.
+# Make sure we handle that scenario properly.
+
+standard_testfile
+set executable ${testfile}
+
+if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
+ return -1
+}
+
+set iterations 10
+for {set i 1} {$i <= $iterations} {incr i} {
+ with_test_prefix "iteration $i" {
+
+ clean_restart ${executable}
+
+ if ![runto_main] {
+ return -1
+ }
+
+ set test "run till end"
+ gdb_test_multiple "continue" "$test" {
+ -re "exited with code 01.*$gdb_prompt $" {
+ pass "$test"
+ }
+ -re "exited with code 02.*$gdb_prompt $" {
+ unsupported "$test (too many CPUs for test?)"
+ }
+ -re "exited normally.*$gdb_prompt $" {
+ pass "$test"
+ }
+ }
+ }
+}