* [PATCH v3 1/4] posix: Consolidate fork implementation
@ 2021-05-03 20:54 Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 2/4] posix: Do not clobber errno by atfork handlers Adhemerval Zanella
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Adhemerval Zanella @ 2021-05-03 20:54 UTC (permalink / raw)
To: libc-alpha
Changes from v2:
* Rebased against master: Linux _Fork implementation now calls
set_robust_list directly (as per 66d99dc53a) and fork_system_setup
update __fork_generation (as perf 3fec7f18bf).
Changes from v1:
* Add the fork_system_setup system hook.
* Move the Linux __fork_generation_pointer out of _Fork to the
NPTL fork_system_setup hook (called from fork).
* Removed comment about POSIX async-signal-safe requirement for
fork.
---
The Linux nptl implementation is used as base for generic fork
implementation to handle the internal locks and mutexes. The
system specific bits are moved a new internal _Fork symbol.
(This new implementation will be used to provide a async-signal-safe
_Fork now that POSIX has clarified that fork might not be
async-signal-safe [1]).
For Hurd it means hat the __nss_database_fork_prepare_parent and
__nss_database_fork_subprocess will be run in a slight different
order.
[1] https://austingroupbugs.net/view.php?id=62
---
include/unistd.h | 2 +
posix/Makefile | 3 +-
posix/_Fork.c | 34 ++++++
posix/fork.c | 112 ++++++++++++++++---
sysdeps/generic/fork.h | 22 ++++
sysdeps/mach/hurd/{fork.c => _Fork.c} | 21 +---
sysdeps/nptl/_Fork.c | 53 +++++++++
sysdeps/nptl/fork.c | 154 --------------------------
sysdeps/nptl/fork.h | 32 ++++++
sysdeps/unix/sysv/linux/arch-fork.h | 3 +
10 files changed, 249 insertions(+), 187 deletions(-)
create mode 100644 posix/_Fork.c
create mode 100644 sysdeps/generic/fork.h
rename sysdeps/mach/hurd/{fork.c => _Fork.c} (98%)
create mode 100644 sysdeps/nptl/_Fork.c
delete mode 100644 sysdeps/nptl/fork.c
create mode 100644 sysdeps/nptl/fork.h
diff --git a/include/unistd.h b/include/unistd.h
index 1363976161..78534dfac5 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -134,6 +134,8 @@ libc_hidden_proto (__setresuid)
libc_hidden_proto (__setresgid)
extern __pid_t __vfork (void);
libc_hidden_proto (__vfork)
+extern __pid_t _Fork (void);
+libc_hidden_proto (_Fork);
extern int __ttyname_r (int __fd, char *__buf, size_t __buflen)
attribute_hidden;
extern int __isatty (int __fd) attribute_hidden;
diff --git a/posix/Makefile b/posix/Makefile
index fa0dc0ea20..ea0cf2fdae 100644
--- a/posix/Makefile
+++ b/posix/Makefile
@@ -39,7 +39,7 @@ routines := \
times \
wait waitpid wait3 wait4 waitid \
alarm sleep pause nanosleep \
- fork vfork _exit register-atfork \
+ fork _Fork vfork _exit register-atfork \
execve fexecve execv execle execl execvp execlp execvpe \
getpid getppid \
getuid geteuid getgid getegid getgroups setuid setgid group_member \
@@ -262,6 +262,7 @@ CFLAGS-execl.os = -fomit-frame-pointer
CFLAGS-execvp.os = -fomit-frame-pointer
CFLAGS-execlp.os = -fomit-frame-pointer
CFLAGS-nanosleep.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-fork.c = $(libio-mtsafe)
tstgetopt-ARGS = -a -b -cfoobar --required foobar --optional=bazbug \
--none random --col --color --colour
diff --git a/posix/_Fork.c b/posix/_Fork.c
new file mode 100644
index 0000000000..4a998c04f1
--- /dev/null
+++ b/posix/_Fork.c
@@ -0,0 +1,34 @@
+/* _Fork implementation. Generic version.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <unistd.h>
+
+/* Clone the calling process, creating an exact copy. Return -1 for errors,
+ 0 to the new process, and the process ID of the new process to the
+ old process.
+ Different than fork, this functions is marked as async-signal-safe by
+ POSIX (by Austin Group issue 62). */
+pid_t
+_Fork (void)
+{
+ __set_errno (ENOSYS);
+ return -1;
+}
+libc_hidden_def (_Fork)
+stub_warning (_Fork)
diff --git a/posix/fork.c b/posix/fork.c
index 05bda04ac5..cc1bdc1232 100644
--- a/posix/fork.c
+++ b/posix/fork.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 1991-2021 Free Software Foundation, Inc.
+/* fork - create a child process.
+ Copyright (C) 1991-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@@ -15,20 +16,105 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <errno.h>
-#include <unistd.h>
+#include <fork.h>
+#include <libio/libioP.h>
+#include <ldsodefs.h>
+#include <malloc/malloc-internal.h>
+#include <nss/nss_database.h>
+#include <register-atfork.h>
+#include <stdio-lock.h>
+#include <sys/single_threaded.h>
+#include <unwind-link.h>
+static void
+fresetlockfiles (void)
+{
+ _IO_ITER i;
+
+ for (i = _IO_iter_begin(); i != _IO_iter_end(); i = _IO_iter_next(i))
+ if ((_IO_iter_file (i)->_flags & _IO_USER_LOCK) == 0)
+ _IO_lock_init (*((_IO_lock_t *) _IO_iter_file(i)->_lock));
+}
-/* Clone the calling process, creating an exact copy.
- Return -1 for errors, 0 to the new process,
- and the process ID of the new process to the old process. */
-int
-__fork (void)
+pid_t
+__libc_fork (void)
{
- __set_errno (ENOSYS);
- return -1;
+ /* Determine if we are running multiple threads. We skip some fork
+ handlers in the single-thread case, to make fork safer to use in
+ signal handlers. */
+ bool multiple_threads = __libc_single_threaded == 0;
+
+ __run_fork_handlers (atfork_run_prepare, multiple_threads);
+
+ struct nss_database_data nss_database_data;
+
+ /* If we are not running multiple threads, we do not have to
+ preserve lock state. If fork runs from a signal handler, only
+ async-signal-safe functions can be used in the child. These data
+ structures are only used by unsafe functions, so their state does
+ not matter if fork was called from a signal handler. */
+ if (multiple_threads)
+ {
+ call_function_static_weak (__nss_database_fork_prepare_parent,
+ &nss_database_data);
+
+ _IO_list_lock ();
+
+ /* Acquire malloc locks. This needs to come last because fork
+ handlers may use malloc, and the libio list lock has an
+ indirect malloc dependency as well (via the getdelim
+ function). */
+ call_function_static_weak (__malloc_fork_lock_parent);
+ }
+
+ pid_t pid = _Fork ();
+
+ if (pid == 0)
+ {
+ fork_system_setup ();
+
+ /* Reset the lock state in the multi-threaded case. */
+ if (multiple_threads)
+ {
+ __libc_unwind_link_after_fork ();
+
+ /* Release malloc locks. */
+ call_function_static_weak (__malloc_fork_unlock_child);
+
+ /* Reset the file list. These are recursive mutexes. */
+ fresetlockfiles ();
+
+ /* Reset locks in the I/O code. */
+ _IO_list_resetlock ();
+
+ call_function_static_weak (__nss_database_fork_subprocess,
+ &nss_database_data);
+ }
+
+ /* Reset the lock the dynamic loader uses to protect its data. */
+ __rtld_lock_initialize (GL(dl_load_lock));
+
+ /* Run the handlers registered for the child. */
+ __run_fork_handlers (atfork_run_child, multiple_threads);
+ }
+ else
+ {
+ /* Release acquired locks in the multi-threaded case. */
+ if (multiple_threads)
+ {
+ /* Release malloc locks, parent process variant. */
+ call_function_static_weak (__malloc_fork_unlock_parent);
+
+ /* We execute this even if the 'fork' call failed. */
+ _IO_list_unlock ();
+ }
+
+ /* Run the handlers registered for the parent. */
+ __run_fork_handlers (atfork_run_parent, multiple_threads);
+ }
+
+ return pid;
}
+weak_alias (__libc_fork, __fork)
libc_hidden_def (__fork)
-stub_warning (fork)
-
-weak_alias (__fork, fork)
+weak_alias (__libc_fork, fork)
diff --git a/sysdeps/generic/fork.h b/sysdeps/generic/fork.h
new file mode 100644
index 0000000000..59a4744913
--- /dev/null
+++ b/sysdeps/generic/fork.h
@@ -0,0 +1,22 @@
+/* System specific fork hooks. Generic version.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+static inline void
+fork_system_setup (void)
+{
+}
diff --git a/sysdeps/mach/hurd/fork.c b/sysdeps/mach/hurd/_Fork.c
similarity index 98%
rename from sysdeps/mach/hurd/fork.c
rename to sysdeps/mach/hurd/_Fork.c
index 92a51693e0..df4ee05faa 100644
--- a/sysdeps/mach/hurd/fork.c
+++ b/sysdeps/mach/hurd/_Fork.c
@@ -58,16 +58,13 @@ DEFINE_HOOK (_hurd_fork_parent_hook, (void));
Return -1 for errors, 0 to the new process,
and the process ID of the new process to the old process. */
pid_t
-__fork (void)
+_Fork (void)
{
jmp_buf env;
pid_t pid;
size_t i;
error_t err;
struct hurd_sigstate *volatile ss;
- struct nss_database_data nss_database_data;
-
- __run_fork_handlers (atfork_run_prepare, true);
ss = _hurd_self_sigstate ();
retry:
@@ -108,9 +105,6 @@ retry:
/* Run things that prepare for forking before we create the task. */
RUN_HOOK (_hurd_fork_prepare_hook, ());
- call_function_static_weak (__nss_database_fork_prepare_parent,
- &nss_database_data);
-
/* Lock things that want to be locked before we fork. */
{
void *const *p;
@@ -670,9 +664,6 @@ retry:
_hurd_malloc_fork_child ();
call_function_static_weak (__malloc_fork_unlock_child);
- call_function_static_weak (__nss_database_fork_subprocess,
- &nss_database_data);
-
/* Run things that want to run in the child task to set up. */
RUN_HOOK (_hurd_fork_child_hook, ());
@@ -723,14 +714,6 @@ retry:
/* Got a signal while inside an RPC of the critical section, retry again */
goto retry;
- if (!err)
- {
- __run_fork_handlers (pid == 0 ? atfork_run_child : atfork_run_parent,
- true);
- }
-
return err ? __hurd_fail (err) : pid;
}
-libc_hidden_def (__fork)
-
-weak_alias (__fork, fork)
+libc_hidden_def (_Fork)
diff --git a/sysdeps/nptl/_Fork.c b/sysdeps/nptl/_Fork.c
new file mode 100644
index 0000000000..4f85c953eb
--- /dev/null
+++ b/sysdeps/nptl/_Fork.c
@@ -0,0 +1,53 @@
+/* _Fork implementation. Linux version.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <arch-fork.h>
+#include <nptl/pthreadP.h>
+
+/* Pointer to the fork generation counter in the thread library. */
+extern unsigned long int *__fork_generation_pointer attribute_hidden;
+
+pid_t
+_Fork (void)
+{
+ pid_t pid = arch_fork (&THREAD_SELF->tid);
+ if (pid == 0)
+ {
+ struct pthread *self = THREAD_SELF;
+
+ /* Initialize the robust mutex list setting in the kernel which has
+ been reset during the fork. We do not check for errors because if
+ it fails here, it must have failed at process startup as well and
+ nobody could have used robust mutexes.
+ Before we do that, we have to clear the list of robust mutexes
+ because we do not inherit ownership of mutexes from the parent.
+ We do not have to set self->robust_head.futex_offset since we do
+ inherit the correct value from the parent. We do not need to clear
+ the pending operation because it must have been zero when fork was
+ called. */
+#if __PTHREAD_MUTEX_HAVE_PREV
+ self->robust_prev = &self->robust_head;
+#endif
+ self->robust_head.list = &self->robust_head;
+ INTERNAL_SYSCALL_CALL (set_robust_list, &self->robust_head,
+ sizeof (struct robust_list_head));
+ }
+ return pid;
+}
+libc_hidden_def (_Fork)
diff --git a/sysdeps/nptl/fork.c b/sysdeps/nptl/fork.c
deleted file mode 100644
index f41c40fca0..0000000000
--- a/sysdeps/nptl/fork.c
+++ /dev/null
@@ -1,154 +0,0 @@
-/* Copyright (C) 2002-2021 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <https://www.gnu.org/licenses/>. */
-
-#include <assert.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sysdep.h>
-#include <libio/libioP.h>
-#include <tls.h>
-#include <hp-timing.h>
-#include <ldsodefs.h>
-#include <stdio-lock.h>
-#include <atomic.h>
-#include <nptl/pthreadP.h>
-#include <register-atfork.h>
-#include <arch-fork.h>
-#include <futex-internal.h>
-#include <malloc/malloc-internal.h>
-#include <nss/nss_database.h>
-#include <unwind-link.h>
-#include <sys/single_threaded.h>
-
-static void
-fresetlockfiles (void)
-{
- _IO_ITER i;
-
- for (i = _IO_iter_begin(); i != _IO_iter_end(); i = _IO_iter_next(i))
- if ((_IO_iter_file (i)->_flags & _IO_USER_LOCK) == 0)
- _IO_lock_init (*((_IO_lock_t *) _IO_iter_file(i)->_lock));
-}
-
-
-pid_t
-__libc_fork (void)
-{
- pid_t pid;
-
- /* Determine if we are running multiple threads. We skip some fork
- handlers in the single-thread case, to make fork safer to use in
- signal handlers. POSIX requires that fork is async-signal-safe,
- but our current fork implementation is not. */
- bool multiple_threads = __libc_single_threaded == 0;
-
- __run_fork_handlers (atfork_run_prepare, multiple_threads);
-
- struct nss_database_data nss_database_data;
-
- /* If we are not running multiple threads, we do not have to
- preserve lock state. If fork runs from a signal handler, only
- async-signal-safe functions can be used in the child. These data
- structures are only used by unsafe functions, so their state does
- not matter if fork was called from a signal handler. */
- if (multiple_threads)
- {
- call_function_static_weak (__nss_database_fork_prepare_parent,
- &nss_database_data);
-
- _IO_list_lock ();
-
- /* Acquire malloc locks. This needs to come last because fork
- handlers may use malloc, and the libio list lock has an
- indirect malloc dependency as well (via the getdelim
- function). */
- call_function_static_weak (__malloc_fork_lock_parent);
- }
-
- pid = arch_fork (&THREAD_SELF->tid);
-
- if (pid == 0)
- {
- struct pthread *self = THREAD_SELF;
-
- /* See __pthread_once. */
- __fork_generation += __PTHREAD_ONCE_FORK_GEN_INCR;
-
- /* Initialize the robust mutex list setting in the kernel which has
- been reset during the fork. We do not check for errors because if
- it fails here, it must have failed at process startup as well and
- nobody could have used robust mutexes.
- Before we do that, we have to clear the list of robust mutexes
- because we do not inherit ownership of mutexes from the parent.
- We do not have to set self->robust_head.futex_offset since we do
- inherit the correct value from the parent. We do not need to clear
- the pending operation because it must have been zero when fork was
- called. */
-#if __PTHREAD_MUTEX_HAVE_PREV
- self->robust_prev = &self->robust_head;
-#endif
- self->robust_head.list = &self->robust_head;
- INTERNAL_SYSCALL_CALL (set_robust_list, &self->robust_head,
- sizeof (struct robust_list_head));
-
- /* Reset the lock state in the multi-threaded case. */
- if (multiple_threads)
- {
- __libc_unwind_link_after_fork ();
-
- /* Release malloc locks. */
- call_function_static_weak (__malloc_fork_unlock_child);
-
- /* Reset the file list. These are recursive mutexes. */
- fresetlockfiles ();
-
- /* Reset locks in the I/O code. */
- _IO_list_resetlock ();
-
- call_function_static_weak (__nss_database_fork_subprocess,
- &nss_database_data);
- }
-
- /* Reset the lock the dynamic loader uses to protect its data. */
- __rtld_lock_initialize (GL(dl_load_lock));
-
- /* Run the handlers registered for the child. */
- __run_fork_handlers (atfork_run_child, multiple_threads);
- }
- else
- {
- /* Release acquired locks in the multi-threaded case. */
- if (multiple_threads)
- {
- /* Release malloc locks, parent process variant. */
- call_function_static_weak (__malloc_fork_unlock_parent);
-
- /* We execute this even if the 'fork' call failed. */
- _IO_list_unlock ();
- }
-
- /* Run the handlers registered for the parent. */
- __run_fork_handlers (atfork_run_parent, multiple_threads);
- }
-
- return pid;
-}
-weak_alias (__libc_fork, __fork)
-libc_hidden_def (__fork)
-weak_alias (__libc_fork, fork)
diff --git a/sysdeps/nptl/fork.h b/sysdeps/nptl/fork.h
new file mode 100644
index 0000000000..8df385494e
--- /dev/null
+++ b/sysdeps/nptl/fork.h
@@ -0,0 +1,32 @@
+/* System specific fork hooks. Linux version.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _FORK_H
+#define _FORK_H
+
+#include <nptl/pthreadP.h>
+#include <sysdep.h>
+
+static inline void
+fork_system_setup (void)
+{
+ /* See __pthread_once. */
+ __fork_generation += __PTHREAD_ONCE_FORK_GEN_INCR;
+}
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/arch-fork.h b/sysdeps/unix/sysv/linux/arch-fork.h
index 35d9397ff8..b846da08f9 100644
--- a/sysdeps/unix/sysv/linux/arch-fork.h
+++ b/sysdeps/unix/sysv/linux/arch-fork.h
@@ -19,6 +19,9 @@
#ifndef __ARCH_FORK_H
#define __ARCH_FORK_H
+#include <sysdep.h>
+#include <sched.h>
+#include <signal.h>
#include <unistd.h>
/* Call the clone syscall with fork semantic. The CTID address is used
--
2.30.2
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v3 2/4] posix: Do not clobber errno by atfork handlers
2021-05-03 20:54 [PATCH v3 1/4] posix: Consolidate fork implementation Adhemerval Zanella
@ 2021-05-03 20:54 ` Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 3/4] Consolidate pthread_atfork Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 4/4] posix: Add _Fork [BZ #4737] Adhemerval Zanella
2 siblings, 0 replies; 4+ messages in thread
From: Adhemerval Zanella @ 2021-05-03 20:54 UTC (permalink / raw)
To: libc-alpha
Changes from v2:
* Set/restore errno unconditionally.
Changes from v1:
* Move the errno set/restore to parent branch.
---
Checked on x86_64-linux-gnu.
---
posix/fork.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/posix/fork.c b/posix/fork.c
index cc1bdc1232..ff527a74f2 100644
--- a/posix/fork.c
+++ b/posix/fork.c
@@ -99,6 +99,9 @@ __libc_fork (void)
}
else
{
+ /* If _Fork failed, preserve its errno value. */
+ int save_errno = errno;
+
/* Release acquired locks in the multi-threaded case. */
if (multiple_threads)
{
@@ -111,6 +114,8 @@ __libc_fork (void)
/* Run the handlers registered for the parent. */
__run_fork_handlers (atfork_run_parent, multiple_threads);
+
+ __set_errno (save_errno);
}
return pid;
--
2.30.2
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v3 3/4] Consolidate pthread_atfork
2021-05-03 20:54 [PATCH v3 1/4] posix: Consolidate fork implementation Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 2/4] posix: Do not clobber errno by atfork handlers Adhemerval Zanella
@ 2021-05-03 20:54 ` Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 4/4] posix: Add _Fork [BZ #4737] Adhemerval Zanella
2 siblings, 0 replies; 4+ messages in thread
From: Adhemerval Zanella @ 2021-05-03 20:54 UTC (permalink / raw)
To: libc-alpha
Changes from v2:
* Rebased against master.
Changes from v1:
* Add comment on pthread_affork_compat.h.
---
The pthread_atfork is similar between Linux and Hurd, only the compat
version bits differs. The generic version is place at sysdeps/pthread
with a common name.
It also fixes an issue with Hurd license, where the static-only object
did not use LGPL.
Checked on x86_64-linux-gnu, i686-linux-gnu, and with a build for
i686-gnu.
---
htl/Makefile | 4 +-
nptl/Makefile | 1 -
sysdeps/htl/old_pt-atfork.c | 26 ------------
sysdeps/htl/pt-atfork.c | 41 -------------------
sysdeps/htl/pthread_atfork_compat.h | 4 ++
sysdeps/nptl/pthread_atfork_compat.h | 4 ++
sysdeps/pthread/Makefile | 4 +-
{nptl => sysdeps/pthread}/pthread_atfork.c | 1 +
.../pthread/pthread_atfork_compat.c | 8 ++--
9 files changed, 18 insertions(+), 75 deletions(-)
delete mode 100644 sysdeps/htl/old_pt-atfork.c
delete mode 100644 sysdeps/htl/pt-atfork.c
create mode 100644 sysdeps/htl/pthread_atfork_compat.h
create mode 100644 sysdeps/nptl/pthread_atfork_compat.h
rename {nptl => sysdeps/pthread}/pthread_atfork.c (98%)
rename nptl/old_pthread_atfork.c => sysdeps/pthread/pthread_atfork_compat.c (84%)
diff --git a/htl/Makefile b/htl/Makefile
index 895a6f777c..0e08680615 100644
--- a/htl/Makefile
+++ b/htl/Makefile
@@ -121,7 +121,6 @@ libpthread-routines := pt-attr pt-attr-destroy pt-attr-getdetachstate \
pt-sigstate-destroy \
pt-sigstate \
\
- old_pt-atfork \
pt-kill \
pt-getcpuclockid \
\
@@ -165,9 +164,8 @@ headers := \
distribute :=
-routines := forward libc_pthread_init alloca_cutoff pt-atfork
+routines := forward libc_pthread_init alloca_cutoff
shared-only-routines = forward
-static-only-routines = pt-atfork
extra-libs := libpthread
extra-libs-others := $(extra-libs)
diff --git a/nptl/Makefile b/nptl/Makefile
index 38f2715c2c..7d41b4e09b 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -47,7 +47,6 @@ routines = \
nptl_deallocate_tsd \
nptl_nthreads \
nptl_setxid \
- old_pthread_atfork \
old_pthread_cond_broadcast \
old_pthread_cond_destroy \
old_pthread_cond_init \
diff --git a/sysdeps/htl/old_pt-atfork.c b/sysdeps/htl/old_pt-atfork.c
deleted file mode 100644
index ca38d6ca42..0000000000
--- a/sysdeps/htl/old_pt-atfork.c
+++ /dev/null
@@ -1,26 +0,0 @@
-/* Register fork handlers. Generic version.
- Copyright (C) 2002-2021 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <https://www.gnu.org/licenses/>. */
-
-#include <shlib-compat.h>
-
-#if SHLIB_COMPAT(libpthread, GLIBC_2_12, GLIBC_2_23)
-# define __pthread_atfork __dyn_pthread_atfork
-# include "pt-atfork.c"
-# undef __pthread_atfork
-compat_symbol (libpthread, __dyn_pthread_atfork, pthread_atfork, GLIBC_2_12);
-#endif
diff --git a/sysdeps/htl/pt-atfork.c b/sysdeps/htl/pt-atfork.c
deleted file mode 100644
index 3902f40835..0000000000
--- a/sysdeps/htl/pt-atfork.c
+++ /dev/null
@@ -1,41 +0,0 @@
-/* Register fork handlers. Generic version.
- Copyright (C) 2002-2021 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <https://www.gnu.org/licenses/>. */
-
-#include <pthread.h>
-#include <pt-internal.h>
-#include <dso_handle.h>
-#include <register-atfork.h>
-
-/* Hide the symbol so that no definition but the one locally in the
- executable or DSO is used. */
-int
-#ifndef __pthread_atfork
-/* Don't mark the compatibility function as hidden. */
-attribute_hidden
-#endif
-__pthread_atfork (void (*prepare) (void),
- void (*parent) (void),
- void (*child) (void))
-{
- return __register_atfork (prepare, parent, child, __dso_handle);
-}
-#ifndef __pthread_atfork
-extern int pthread_atfork (void (*prepare) (void), void (*parent) (void),
- void (*child) (void)) attribute_hidden;
-weak_alias (__pthread_atfork, pthread_atfork)
-#endif
diff --git a/sysdeps/htl/pthread_atfork_compat.h b/sysdeps/htl/pthread_atfork_compat.h
new file mode 100644
index 0000000000..08afccbb3c
--- /dev/null
+++ b/sysdeps/htl/pthread_atfork_compat.h
@@ -0,0 +1,4 @@
+/* The compat version for the dynamic pthread_atfork provided by libpthread,
+ before supported __dso_handle was added. */
+#define PTHREAD_ATFORK_COMPAT_INTRODUCED GLIBC_2_12
+#define PTHREAD_ATFORK_COMPAT_OBSOLETED GLIBC_2_23
diff --git a/sysdeps/nptl/pthread_atfork_compat.h b/sysdeps/nptl/pthread_atfork_compat.h
new file mode 100644
index 0000000000..38edcbefe5
--- /dev/null
+++ b/sysdeps/nptl/pthread_atfork_compat.h
@@ -0,0 +1,4 @@
+/* The compat versions for the dynamic pthread_atfork provided by libpthread,
+ before supported __dso_handle was added. */
+#define PTHREAD_ATFORK_COMPAT_INTRODUCED GLIBC_2_0
+#define PTHREAD_ATFORK_COMPAT_OBSOLETED GLIBC_2_3
diff --git a/sysdeps/pthread/Makefile b/sysdeps/pthread/Makefile
index 54bb11bab9..282425ade5 100644
--- a/sysdeps/pthread/Makefile
+++ b/sysdeps/pthread/Makefile
@@ -29,7 +29,7 @@ endif
ifneq (,$(filter $(subdir),htl nptl))
headers += threads.h
-routines += thrd_current thrd_equal thrd_sleep thrd_yield
+routines += thrd_current thrd_equal thrd_sleep thrd_yield pthread_atfork
libpthread-routines += thrd_create thrd_detach thrd_join
@@ -47,6 +47,7 @@ $(libpthread-routines-var) += \
mtx_timedlock \
mtx_trylock \
mtx_unlock \
+ pthread_atfork_compat \
thrd_exit \
tss_create \
tss_delete \
@@ -123,6 +124,7 @@ tests += tst-cnd-basic tst-mtx-trylock tst-cnd-broadcast \
tst-unwind-thread \
tst-pt-vfork1 tst-pt-vfork2 tst-vfork1x tst-vfork2x \
+static-only-routines = pthread_atfork
# Files which must not be linked with libpthread.
tests-nolibpthread += tst-unload
diff --git a/nptl/pthread_atfork.c b/sysdeps/pthread/pthread_atfork.c
similarity index 98%
rename from nptl/pthread_atfork.c
rename to sysdeps/pthread/pthread_atfork.c
index 6398688dab..7646fe7efc 100644
--- a/nptl/pthread_atfork.c
+++ b/sysdeps/pthread/pthread_atfork.c
@@ -36,6 +36,7 @@
#include "pthreadP.h"
#include <register-atfork.h>
#include <dso_handle.h>
+#include <register-atfork.h>
/* Hide the symbol so that no definition but the one locally in the
diff --git a/nptl/old_pthread_atfork.c b/sysdeps/pthread/pthread_atfork_compat.c
similarity index 84%
rename from nptl/old_pthread_atfork.c
rename to sysdeps/pthread/pthread_atfork_compat.c
index 675227c559..4533f765d1 100644
--- a/nptl/old_pthread_atfork.c
+++ b/sysdeps/pthread/pthread_atfork_compat.c
@@ -1,6 +1,6 @@
-/* Copyright (C) 2002-2021 Free Software Foundation, Inc.
+/* Compat pthread_atfork implementation.
+ Copyright (C) 2002-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
@@ -16,11 +16,13 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
+#include <pthread_atfork_compat.h>
#include <shlib-compat.h>
#if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_3)
# define __pthread_atfork __dyn_pthread_atfork
# include "pthread_atfork.c"
# undef __pthread_atfork
-compat_symbol (libpthread, __dyn_pthread_atfork, pthread_atfork, GLIBC_2_0);
+compat_symbol (libpthread, __dyn_pthread_atfork, pthread_atfork,
+ PTHREAD_ATFORK_COMPAT_INTRODUCED);
#endif
--
2.30.2
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v3 4/4] posix: Add _Fork [BZ #4737]
2021-05-03 20:54 [PATCH v3 1/4] posix: Consolidate fork implementation Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 2/4] posix: Do not clobber errno by atfork handlers Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 3/4] Consolidate pthread_atfork Adhemerval Zanella
@ 2021-05-03 20:54 ` Adhemerval Zanella
2 siblings, 0 replies; 4+ messages in thread
From: Adhemerval Zanella @ 2021-05-03 20:54 UTC (permalink / raw)
To: libc-alpha
Changes from v2:
* Rebased against master.
Changes from v1:
* Add NEWS entry and fix grammar issue on commit message.
---
Austin Group issue 62 [1] dropped the async-signal-safe requirement
for fork and provided a async-signal-safe _Fork replacement that
does not run the atfork handlers. It will be included in the next
POSIX standard.
It allow to close a long standing issue to make fork AS-safe (BZ#4737).
As indicated on the bug, besides the internal lock for the atfork
handlers itself; there is no guarantee that the handlers itself will
not introduce more AS-safe issues.
The idea is synchronize fork with the required internal locks to allow
children in multithread processes to use mostly of standard function
(even though POSIX states only AS-safe function should be used). On
signal handles, _Fork should be used intead and only AS-safe functions
should be used.
For testing, the new tst-_Fork only check basic usage. I also added
a new tst-mallocfork3 which uses the same strategy to check for
deadlock of tst-mallocfork2 but using threads instead of subprocesses
(and it does deadlock if it replaces _Fork with fork).
[1] https://austingroupbugs.net/view.php?id=62
---
NEWS | 8 +
malloc/Makefile | 3 +
malloc/tst-mallocfork3.c | 213 +++++++++++++++++
manual/process.texi | 39 ++--
posix/Makefile | 3 +-
posix/Versions | 1 +
posix/fork.c | 5 +-
posix/tst-_Fork.c | 218 ++++++++++++++++++
posix/unistd.h | 7 +
sysdeps/unix/sysv/linux/aarch64/libc.abilist | 1 +
sysdeps/unix/sysv/linux/alpha/libc.abilist | 1 +
sysdeps/unix/sysv/linux/arc/libc.abilist | 1 +
sysdeps/unix/sysv/linux/arm/be/libc.abilist | 1 +
sysdeps/unix/sysv/linux/arm/le/libc.abilist | 1 +
sysdeps/unix/sysv/linux/csky/libc.abilist | 1 +
sysdeps/unix/sysv/linux/hppa/libc.abilist | 1 +
sysdeps/unix/sysv/linux/i386/libc.abilist | 1 +
sysdeps/unix/sysv/linux/ia64/libc.abilist | 1 +
.../sysv/linux/m68k/coldfire/libc.abilist | 1 +
.../unix/sysv/linux/m68k/m680x0/libc.abilist | 1 +
.../sysv/linux/microblaze/be/libc.abilist | 1 +
.../sysv/linux/microblaze/le/libc.abilist | 1 +
.../sysv/linux/mips/mips32/fpu/libc.abilist | 1 +
.../sysv/linux/mips/mips32/nofpu/libc.abilist | 1 +
.../sysv/linux/mips/mips64/n32/libc.abilist | 1 +
.../sysv/linux/mips/mips64/n64/libc.abilist | 1 +
sysdeps/unix/sysv/linux/nios2/libc.abilist | 1 +
.../linux/powerpc/powerpc32/fpu/libc.abilist | 1 +
.../powerpc/powerpc32/nofpu/libc.abilist | 1 +
.../linux/powerpc/powerpc64/be/libc.abilist | 1 +
.../linux/powerpc/powerpc64/le/libc.abilist | 1 +
.../unix/sysv/linux/riscv/rv32/libc.abilist | 1 +
.../unix/sysv/linux/riscv/rv64/libc.abilist | 1 +
.../unix/sysv/linux/s390/s390-32/libc.abilist | 1 +
.../unix/sysv/linux/s390/s390-64/libc.abilist | 1 +
sysdeps/unix/sysv/linux/sh/be/libc.abilist | 1 +
sysdeps/unix/sysv/linux/sh/le/libc.abilist | 1 +
.../sysv/linux/sparc/sparc32/libc.abilist | 1 +
.../sysv/linux/sparc/sparc64/libc.abilist | 1 +
.../unix/sysv/linux/x86_64/64/libc.abilist | 1 +
.../unix/sysv/linux/x86_64/x32/libc.abilist | 1 +
41 files changed, 512 insertions(+), 17 deletions(-)
create mode 100644 malloc/tst-mallocfork3.c
create mode 100644 posix/tst-_Fork.c
diff --git a/NEWS b/NEWS
index a5631af920..22a5a82db5 100644
--- a/NEWS
+++ b/NEWS
@@ -23,6 +23,14 @@ Major new features:
/proc to be mounted. However, different than fexecve, if the syscall is not
supported by the kernel an error is returned instead of trying a fallback.
+* The function _Fork has been added as a async-signal-safe fork
+ replacement since Austin Group issue 62 droped the async-signal-safe
+ requirement for fork (and it will be included in the future POSIX
+ standard). The new _Fork function does not run any atfork function neither
+ resets any internal state or lock (such as the malloc one) and only
+ sets up a minimal state required to call async-signal-safe functions (such
+ as raise or execve). This function is currently a GNU extension.
+
Deprecated and removed features, and other changes affecting compatibility:
* The function pthread_mutex_consistent_np has been deprecated; programs
diff --git a/malloc/Makefile b/malloc/Makefile
index 641967c512..833c9c499e 100644
--- a/malloc/Makefile
+++ b/malloc/Makefile
@@ -31,6 +31,7 @@ tests := mallocbug tst-malloc tst-valloc tst-calloc tst-obstack \
tst-malloc-backtrace tst-malloc-thread-exit \
tst-malloc-thread-fail tst-malloc-fork-deadlock \
tst-mallocfork2 \
+ tst-mallocfork3 \
tst-interpose-nothread \
tst-interpose-thread \
tst-alloc_buffer \
@@ -115,6 +116,8 @@ libmemusage-inhibit-o = $(filter-out .os,$(object-suffixes))
$(objpfx)tst-malloc-backtrace: $(shared-thread-library)
$(objpfx)tst-malloc-thread-exit: $(shared-thread-library)
$(objpfx)tst-malloc-thread-fail: $(shared-thread-library)
+$(objpfx)tst-mallocfork3: $(shared-thread-library)
+$(objpfx)tst-mallocfork3-mcheck: $(shared-thread-library)
$(objpfx)tst-malloc-fork-deadlock: $(shared-thread-library)
$(objpfx)tst-malloc-stats-cancellation: $(shared-thread-library)
$(objpfx)tst-malloc-backtrace-mcheck: $(shared-thread-library)
diff --git a/malloc/tst-mallocfork3.c b/malloc/tst-mallocfork3.c
new file mode 100644
index 0000000000..4ac99eea43
--- /dev/null
+++ b/malloc/tst-mallocfork3.c
@@ -0,0 +1,213 @@
+/* Test case for async-signal-safe _Fork (with respect to malloc).
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If
+ not, see <https://www.gnu.org/licenses/>. */
+
+/* This test is similar to tst-mallocfork2.c, but specifically stress
+ the async-signal-safeness of _Fork on multithread environment. */
+
+#include <array_length.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <support/check.h>
+#include <support/support.h>
+#include <support/xsignal.h>
+#include <support/xthread.h>
+#include <support/xunistd.h>
+#include <sys/wait.h>
+
+/* How many malloc objects to keep arond. */
+enum { malloc_objects = 1009 };
+
+/* The maximum size of an object. */
+enum { malloc_maximum_size = 70000 };
+
+/* How many iterations the test performs before exiting. */
+enum { iterations = 10000 };
+
+/* Barrier for synchronization with the threads sending SIGUSR1
+ signals, to make it more likely that the signals arrive during a
+ fork/free/malloc call. */
+static pthread_barrier_t barrier;
+
+/* Set to 1 if SIGUSR1 is received. Used to detect a signal during
+ fork/free/malloc. */
+static volatile sig_atomic_t sigusr1_received;
+
+/* Periodically set to 1, to indicate that the thread is making
+ progress. Checked by liveness_signal_handler. */
+static volatile sig_atomic_t progress_indicator = 1;
+
+/* Set to 1 if an error occurs in the signal handler. */
+static volatile sig_atomic_t error_indicator = 0;
+
+static void
+sigusr1_handler (int signo)
+{
+ sigusr1_received = 1;
+
+ /* Perform a fork with a trivial subprocess. */
+ pid_t pid = _Fork ();
+ if (pid == -1)
+ {
+ write_message ("error: fork\n");
+ error_indicator = 1;
+ return;
+ }
+ if (pid == 0)
+ _exit (0);
+ int status;
+ int ret = TEMP_FAILURE_RETRY (waitpid (pid, &status, 0));
+ if (ret < 0)
+ {
+ write_message ("error: waitpid\n");
+ error_indicator = 1;
+ return;
+ }
+ if (status != 0)
+ {
+ write_message ("error: unexpected exit status from subprocess\n");
+ error_indicator = 1;
+ return;
+ }
+}
+
+static void
+liveness_signal_handler (int signo)
+{
+ if (progress_indicator)
+ progress_indicator = 0;
+ else
+ write_message ("warning: thread seems to be stuck\n");
+}
+
+struct signal_send_args
+{
+ pthread_t target;
+ int signo;
+ bool sleep;
+};
+#define SIGNAL_SEND_GET_ARG(arg, field) \
+ (((struct signal_send_args *)(arg))->field)
+
+/* Send SIGNO to the parent thread. If SLEEP, wait a second between
+ signals, otherwise use barriers to delay sending signals. */
+static void *
+signal_sender (void *args)
+{
+ int signo = SIGNAL_SEND_GET_ARG (args, signo);
+ bool sleep = SIGNAL_SEND_GET_ARG (args, sleep);
+
+ pthread_t target = SIGNAL_SEND_GET_ARG (args, target);
+ while (true)
+ {
+ if (!sleep)
+ xpthread_barrier_wait (&barrier);
+ xpthread_kill (target, signo);
+ if (sleep)
+ usleep (1 * 1000 * 1000);
+ else
+ xpthread_barrier_wait (&barrier);
+ }
+ return NULL;
+}
+
+static pthread_t sigusr1_sender[5];
+static pthread_t sigusr2_sender;
+
+static int
+do_test (void)
+{
+ xsignal (SIGUSR1, sigusr1_handler);
+ xsignal (SIGUSR2, liveness_signal_handler);
+
+ pthread_t self = pthread_self ();
+
+ struct signal_send_args sigusr2_args = { self, SIGUSR2, true };
+ sigusr2_sender = xpthread_create (NULL, signal_sender, &sigusr2_args);
+
+ /* Send SIGUSR1 signals from several threads. Hopefully, one
+ signal will hit one of the ciritical functions. Use a barrier to
+ avoid sending signals while not running fork/free/malloc. */
+ struct signal_send_args sigusr1_args = { self, SIGUSR1, false };
+ xpthread_barrier_init (&barrier, NULL,
+ array_length (sigusr1_sender) + 1);
+ for (size_t i = 0; i < array_length (sigusr1_sender); ++i)
+ sigusr1_sender[i] = xpthread_create (NULL, signal_sender, &sigusr1_args);
+
+ void *objects[malloc_objects] = {};
+ unsigned int fork_signals = 0;
+ unsigned int free_signals = 0;
+ unsigned int malloc_signals = 0;
+ unsigned int seed = 1;
+ for (int i = 0; i < iterations; ++i)
+ {
+ progress_indicator = 1;
+ int slot = rand_r (&seed) % malloc_objects;
+ size_t size = rand_r (&seed) % malloc_maximum_size;
+
+ /* Occasionally do a fork first, to catch deadlocks there as
+ well (see bug 24161). */
+ bool do_fork = (rand_r (&seed) % 7) == 0;
+
+ xpthread_barrier_wait (&barrier);
+ if (do_fork)
+ {
+ sigusr1_received = 0;
+ pid_t pid = _Fork ();
+ TEST_VERIFY_EXIT (pid != -1);
+ if (sigusr1_received)
+ ++fork_signals;
+ if (pid == 0)
+ _exit (0);
+ int status;
+ int ret = TEMP_FAILURE_RETRY (waitpid (pid, &status, 0));
+ if (ret < 0)
+ FAIL_EXIT1 ("waitpid: %m");
+ TEST_COMPARE (status, 0);
+ }
+ sigusr1_received = 0;
+ free (objects[slot]);
+ if (sigusr1_received)
+ ++free_signals;
+ sigusr1_received = 0;
+ objects[slot] = malloc (size);
+ if (sigusr1_received)
+ ++malloc_signals;
+ xpthread_barrier_wait (&barrier);
+
+ if (objects[slot] == NULL || error_indicator != 0)
+ {
+ printf ("error: malloc: %m\n");
+ return 1;
+ }
+ }
+
+ /* Clean up allocations. */
+ for (int slot = 0; slot < malloc_objects; ++slot)
+ free (objects[slot]);
+
+ printf ("info: signals received during fork: %u\n", fork_signals);
+ printf ("info: signals received during free: %u\n", free_signals);
+ printf ("info: signals received during malloc: %u\n", malloc_signals);
+
+ return 0;
+}
+
+#define TIMEOUT 100
+#include <support/test-driver.c>
diff --git a/manual/process.texi b/manual/process.texi
index 54e65f76c6..e17149ce60 100644
--- a/manual/process.texi
+++ b/manual/process.texi
@@ -138,8 +138,8 @@ creating a process and making it run another program.
@cindex parent process
@cindex subprocess
A new processes is created when one of the functions
-@code{posix_spawn}, @code{fork}, or @code{vfork} is called. (The
-@code{system} and @code{popen} also create new processes internally.)
+@code{posix_spawn}, @code{fork}, @code{_Fork} or @code{vfork} is called.
+(The @code{system} and @code{popen} also create new processes internally.)
Due to the name of the @code{fork} function, the act of creating a new
process is sometimes called @dfn{forking} a process. Each new process
(the @dfn{child process} or @dfn{subprocess}) is allocated a process
@@ -155,9 +155,10 @@ limited information about why the child terminated---for example, its
exit status code.
A newly forked child process continues to execute the same program as
-its parent process, at the point where the @code{fork} call returns.
-You can use the return value from @code{fork} to tell whether the program
-is running in the parent process or the child.
+its parent process, at the point where the @code{fork} or @code{_Fork}
+call returns. You can use the return value from @code{fork} or
+@code{_Fork} to tell whether the program is running in the parent process
+or the child.
@cindex process image
Having several processes run the same program is only occasionally
@@ -249,16 +250,13 @@ It is declared in the header file @file{unistd.h}.
@deftypefun pid_t fork (void)
@standards{POSIX.1, unistd.h}
@safety{@prelim{}@mtsafe{}@asunsafe{@ascuplugin{}}@acunsafe{@aculock{}}}
-@c The nptl/.../linux implementation safely collects fork_handlers into
-@c an alloca()ed linked list and increments ref counters; it uses atomic
-@c ops and retries, avoiding locking altogether. It then takes the
-@c IO_list lock, resets the thread-local pid, and runs fork. The parent
-@c restores the thread-local pid, releases the lock, and runs parent
-@c handlers, decrementing the ref count and signaling futex wait if
-@c requested by unregister_atfork. The child bumps the fork generation,
-@c sets the thread-local pid, resets cpu clocks, initializes the robust
-@c mutex list, the stream locks, the IO_list lock, the dynamic loader
-@c lock, runs the child handlers, reseting ref counters to 1, and
+@c The posix/fork.c implementation iterates over the fork_handlers
+@c using a lock. It then takes the IO_list lock, resets the thread-local
+@c pid, and runs fork. The parent releases the lock, and runs parent
+@c handlers, and unlocks the internal lock. The child bumps the fork
+@c generation, sets the thread-local pid, resets cpu clocks, initializes
+@c the robust mutex list, the stream locks, the IO_list lock, the dynamic
+@c loader lock, runs the child handlers, reseting ref counters to 1, and
@c initializes the fork lock. These are all safe, unless atfork
@c handlers themselves are unsafe.
The @code{fork} function creates a new process.
@@ -322,6 +320,17 @@ process is cleared. (The child process inherits its mask of blocked
signals and signal actions from the parent process.)
@end itemize
+@deftypefun pid_t _Fork (void)
+@standards{GNU, unistd.h}
+@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
+The @code{_Fork} function is similar to @code{fork} but does not issue
+any atfork callback registered with @code{pthread_atfork} neither reset
+any internal state or locks (such as the malloc one) and only setup a
+minimal state required to call async-signal-safe functions (such as raise
+or execve).
+
+It is an async-signal-safe replacement of @code{fork}.
+@end deftypefun
@deftypefun pid_t vfork (void)
@standards{BSD, unistd.h}
diff --git a/posix/Makefile b/posix/Makefile
index ea0cf2fdae..9bcaef611c 100644
--- a/posix/Makefile
+++ b/posix/Makefile
@@ -126,7 +126,7 @@ test-srcs := globtest
tests += wordexp-test tst-exec tst-spawn tst-spawn2 tst-spawn3
endif
ifeq (yesyes,$(build-shared)$(have-thread-library))
-tests += tst-getopt-cancel
+tests += tst-getopt-cancel tst-_Fork
endif
tests-static = tst-exec-static tst-spawn-static
tests += $(tests-static)
@@ -295,6 +295,7 @@ $(objpfx)ptestcases.h: PTESTS PTESTS2C.sed
$(objpfx)runptests.o: $(objpfx)ptestcases.h
$(objpfx)tst-getopt-cancel: $(shared-thread-library)
+$(objpfx)tst-_Fork: $(shared-thread-library)
test-xfail-annexc = yes
$(objpfx)annexc.out: $(objpfx)annexc
diff --git a/posix/Versions b/posix/Versions
index b77e251e00..4a5bd3a274 100644
--- a/posix/Versions
+++ b/posix/Versions
@@ -148,6 +148,7 @@ libc {
GLIBC_2.30 {
}
GLIBC_2.34 {
+ _Fork;
execveat;
}
GLIBC_PRIVATE {
diff --git a/posix/fork.c b/posix/fork.c
index ff527a74f2..f34ec72aa6 100644
--- a/posix/fork.c
+++ b/posix/fork.c
@@ -41,7 +41,10 @@ __libc_fork (void)
{
/* Determine if we are running multiple threads. We skip some fork
handlers in the single-thread case, to make fork safer to use in
- signal handlers. */
+ signal handlers. Although POSIX has dropped async-signal-safe
+ requirement for fork (Austin Group tracker issue #62) this is
+ best effort to make is async-signal-safe at least for single-thread
+ case. */
bool multiple_threads = __libc_single_threaded == 0;
__run_fork_handlers (atfork_run_prepare, multiple_threads);
diff --git a/posix/tst-_Fork.c b/posix/tst-_Fork.c
new file mode 100644
index 0000000000..29a7ab6aaf
--- /dev/null
+++ b/posix/tst-_Fork.c
@@ -0,0 +1,218 @@
+/* Basic tests for _Fork.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <array_length.h>
+#include <stdlib.h>
+#include <string.h>
+#include <pthread.h>
+#include <stdbool.h>
+#include <support/check.h>
+#include <support/xsignal.h>
+#include <support/temp_file.h>
+#include <support/xunistd.h>
+#include <support/xthread.h>
+
+/* For single-thread, _Fork behaves like fork. */
+static int
+singlethread_test (void)
+{
+ const char testdata1[] = "abcdefghijklmnopqrtuvwxz";
+ enum { testdatalen1 = array_length (testdata1) };
+ const char testdata2[] = "01234567890";
+ enum { testdatalen2 = array_length (testdata2) };
+
+ pid_t ppid = getpid ();
+
+ int tempfd = create_temp_file ("tst-_Fork", NULL);
+
+ /* Check if the opened file is shared between process by read and write
+ some data on parent and child processes. */
+ xwrite (tempfd, testdata1, testdatalen1);
+ off_t off = xlseek (tempfd, 0, SEEK_CUR);
+ TEST_COMPARE (off, testdatalen1);
+
+ pid_t pid = _Fork ();
+ TEST_VERIFY_EXIT (pid != -1);
+ if (pid == 0)
+ {
+ TEST_VERIFY_EXIT (getpid () != ppid);
+ TEST_COMPARE (getppid(), ppid);
+
+ TEST_COMPARE (xlseek (tempfd, 0, SEEK_CUR), testdatalen1);
+
+ xlseek (tempfd, 0, SEEK_SET);
+ char buf[testdatalen1];
+ TEST_COMPARE (read (tempfd, buf, sizeof (buf)), testdatalen1);
+ TEST_COMPARE (memcmp (buf, testdata1, testdatalen1), 0);
+
+ xlseek (tempfd, 0, SEEK_SET);
+ xwrite (tempfd, testdata2, testdatalen2);
+
+ close (tempfd);
+
+ _exit (EXIT_SUCCESS);
+ }
+
+ int status;
+ xwaitpid (pid, &status, 0);
+ TEST_VERIFY (WIFEXITED (status));
+ TEST_COMPARE (WEXITSTATUS (status), EXIT_SUCCESS);
+
+ TEST_COMPARE (xlseek (tempfd, 0, SEEK_CUR), testdatalen2);
+
+ xlseek (tempfd, 0, SEEK_SET);
+ char buf[testdatalen2];
+ TEST_COMPARE (read (tempfd, buf, sizeof (buf)), testdatalen2);
+
+ TEST_COMPARE (memcmp (buf, testdata2, testdatalen2), 0);
+
+ return 0;
+}
+
+
+static volatile sig_atomic_t sigusr1_handler_ran;
+static pid_t sig_pid = -1;
+#define SIG_PID_EXIT_CODE 20
+
+static void
+sigusr1_handler (int signum)
+{
+ TEST_COMPARE (signum, SIGUSR1);
+
+ pid_t ppid = getpid ();
+
+ sig_pid = _Fork ();
+ TEST_VERIFY_EXIT (sig_pid != -1);
+ if (sig_pid == 0)
+ {
+ TEST_VERIFY_EXIT (getpid () != ppid);
+ TEST_COMPARE (getppid(), ppid);
+
+ _exit (SIG_PID_EXIT_CODE);
+ }
+
+ sigusr1_handler_ran = 1;
+}
+
+/* _Fork is async-signal-safe, so check if it can successfully issue
+ a new process in a signal handler. */
+static int
+singlethread_signal_test (void)
+{
+ xsignal (SIGUSR1, &sigusr1_handler);
+ /* Assume synchronous signal handling. */
+ xraise (SIGUSR1);
+ TEST_COMPARE (sigusr1_handler_ran, 1);
+
+ int status;
+ xwaitpid (sig_pid, &status, 0);
+ TEST_VERIFY (WIFEXITED (status));
+ TEST_COMPARE (WEXITSTATUS (status), SIG_PID_EXIT_CODE);
+
+ xsignal (SIGUSR1, SIG_DFL);
+
+ return 0;
+}
+
+
+static bool atfork_prepare_var;
+static bool atfork_parent_var;
+static bool atfork_child_var;
+
+static void
+atfork_prepare (void)
+{
+ atfork_prepare_var = true;
+}
+
+static void
+atfork_parent (void)
+{
+ atfork_parent_var = true;
+}
+
+static void
+atfork_child (void)
+{
+ atfork_child_var = true;
+}
+
+/* Different than fork, _Fork does not execute any pthread_atfork
+ handlers. */
+static int
+singlethread_atfork_test (void)
+{
+ pthread_atfork (atfork_prepare, atfork_parent, atfork_child);
+ singlethread_test ();
+ TEST_COMPARE (atfork_prepare_var, false);
+ TEST_COMPARE (atfork_parent_var, false);
+ TEST_COMPARE (atfork_child_var, false);
+
+ return 0;
+}
+
+
+static void *
+mt_atfork_test (void *args)
+{
+ singlethread_atfork_test ();
+
+ return NULL;
+}
+
+static int
+multithread_atfork_test (void)
+{
+ pthread_t thr = xpthread_create (NULL, mt_atfork_test, NULL);
+ xpthread_join (thr);
+
+ return 0;
+}
+
+
+static void *
+mt_signal_test (void *args)
+{
+ singlethread_signal_test ();
+
+ return NULL;
+}
+
+static int
+multithread_signal_test (void)
+{
+ pthread_t thr = xpthread_create (NULL, mt_signal_test, NULL);
+ xpthread_join (thr);
+
+ return 0;
+}
+
+
+static int
+do_test (void)
+{
+ singlethread_atfork_test ();
+ singlethread_signal_test ();
+
+ multithread_atfork_test ();
+ multithread_signal_test ();
+
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/posix/unistd.h b/posix/unistd.h
index d9d8929f71..fa06c890ba 100644
--- a/posix/unistd.h
+++ b/posix/unistd.h
@@ -781,6 +781,13 @@ extern __pid_t fork (void) __THROWNL;
extern __pid_t vfork (void) __THROW;
#endif /* Use misc or XPG < 7. */
+#ifdef __USE_GNU
+/* This is similar to fork, however it does not run the atfork handlers
+ neither reinitialize any internal locks in multithread case.
+ Different than fork, _Fork is async-signal-safe. */
+extern __pid_t _Fork (void) __THROWNL;
+#endif
+
/* Return the pathname of the terminal FD is open on, or NULL on errors.
The returned storage is good only until the next call to this function. */
diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
index 29094366e3..cef176bf49 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
@@ -2273,6 +2273,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
index 74998fc5b0..a283233386 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -2354,6 +2354,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist
index 8ce7184069..83e5044311 100644
--- a/sysdeps/unix/sysv/linux/arc/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arc/libc.abilist
@@ -2032,6 +2032,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
index 3eb6816ffc..c92d854d71 100644
--- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
@@ -180,6 +180,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
index bd3a7c2830..965e429b9f 100644
--- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
@@ -177,6 +177,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
index 14dade3ad5..99e018ab34 100644
--- a/sysdeps/unix/sysv/linux/csky/libc.abilist
+++ b/sysdeps/unix/sysv/linux/csky/libc.abilist
@@ -2216,6 +2216,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
index 286ac0c44d..3baee07b5f 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -2167,6 +2167,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
index e33fe31138..9213cf6f5f 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -2343,6 +2343,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __isnanf128 F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
index eedd7293e2..09e648d116 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -2200,6 +2200,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __isnanf128 F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
index 0cf1c052db..693059a29d 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -181,6 +181,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
index 9a457376e2..d93f1ad9d3 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -2287,6 +2287,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
index 540e503a0b..f47653c75e 100644
--- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
@@ -2267,6 +2267,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
index f630215296..bc597a364d 100644
--- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
@@ -2264,6 +2264,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
index f4f2d706c0..4ff26334a4 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -2250,6 +2250,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
index ee5b775cd0..62fc4300a7 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -2248,6 +2248,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
index 6d9798fb9a..57961e207a 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -2256,6 +2256,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
index e6d6053906..d232b52f1d 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -2250,6 +2250,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
index 743d981081..28f2b84d86 100644
--- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
@@ -2306,6 +2306,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
index e173d5a95c..ac8e4e42b1 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -2314,6 +2314,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
index b5e32bef98..33ae79b1e4 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -2347,6 +2347,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
index 20168d3df3..f3f01b7530 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
@@ -2168,6 +2168,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
index 5f94b1ce64..e48f556e18 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
@@ -2468,6 +2468,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __isnanf128 F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
index 3fe5e16e5d..135566d49b 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
@@ -2034,6 +2034,7 @@ GLIBC_2.33 wprintf F
GLIBC_2.33 write F
GLIBC_2.33 writev F
GLIBC_2.33 wscanf F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
index f9beb99367..f8ef5b129e 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
@@ -2234,6 +2234,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
index bfa492a8c7..433b8a77de 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -2312,6 +2312,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
index 27e9b47768..28fdea2b53 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -2205,6 +2205,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
index b5cd5109ad..e268195353 100644
--- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
@@ -2174,6 +2174,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
index 1b20c9fcb1..297f203f4a 100644
--- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
@@ -2171,6 +2171,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
index c99298c588..ef6e31286b 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -2303,6 +2303,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
index 19c6041c49..356d615440 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -2222,6 +2222,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
GLIBC_2.34 __pthread_key_create F
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
index 9c5096c1d9..77ada190ea 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -2182,6 +2182,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __isnanf128 F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
index 15bec846ec..40f351de5d 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
@@ -2287,6 +2287,7 @@ GLIBC_2.33 mknod F
GLIBC_2.33 mknodat F
GLIBC_2.33 stat F
GLIBC_2.33 stat64 F
+GLIBC_2.34 _Fork F
GLIBC_2.34 __isnanf128 F
GLIBC_2.34 __libc_start_main F
GLIBC_2.34 __pthread_cleanup_routine F
--
2.30.2
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-05-03 20:54 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-05-03 20:54 [PATCH v3 1/4] posix: Consolidate fork implementation Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 2/4] posix: Do not clobber errno by atfork handlers Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 3/4] Consolidate pthread_atfork Adhemerval Zanella
2021-05-03 20:54 ` [PATCH v3 4/4] posix: Add _Fork [BZ #4737] Adhemerval Zanella
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