From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: libc-alpha@sourceware.org
Subject: [PATCH 01/15] nptl: Set cancellation type and state on pthread_exit (BZ #28267)
Date: Thu, 30 Sep 2021 17:00:37 -0300 [thread overview]
Message-ID: <20210930200051.1017457-2-adhemerval.zanella@linaro.org> (raw)
In-Reply-To: <20210930200051.1017457-1-adhemerval.zanella@linaro.org>
It is required by POSIX XSH 2.9.5 Thread Cancellation under the heading
Thread Cancellation Cleanup Handlers.
Checked x86_64-linux-gnu.
---
nptl/Makefile | 3 +-
nptl/cancellation.c | 7 ++-
nptl/pthread_cancel.c | 1 -
nptl/pthread_exit.c | 4 +-
nptl/pthread_testcancel.c | 1 -
nptl/tst-cleanup5.c | 129 ++++++++++++++++++++++++++++++++++++++
sysdeps/nptl/pthreadP.h | 18 ++++--
7 files changed, 152 insertions(+), 11 deletions(-)
create mode 100644 nptl/tst-cleanup5.c
diff --git a/nptl/Makefile b/nptl/Makefile
index ff4d590f11..e1e195cc15 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -306,7 +306,8 @@ tests = tst-attr2 tst-attr3 tst-default-attr \
tst-pthread-gdb-attach tst-pthread-gdb-attach-static \
tst-pthread_exit-nothreads \
tst-pthread_exit-nothreads-static \
- tst-thread-setspecific
+ tst-thread-setspecific \
+ tst-cleanup5
tests-nolibpthread = \
tst-pthread_exit-nothreads \
diff --git a/nptl/cancellation.c b/nptl/cancellation.c
index 44f8417845..7cef9487bf 100644
--- a/nptl/cancellation.c
+++ b/nptl/cancellation.c
@@ -41,7 +41,6 @@ __pthread_enable_asynccancel (void)
&& !(ch & EXITING_BITMASK)
&& !(ch & TERMINATED_BITMASK))
{
- THREAD_SETMEM (self, result, PTHREAD_CANCELED);
__do_cancel ();
}
@@ -63,3 +62,9 @@ __pthread_disable_asynccancel (int oldtype)
self->canceltype = PTHREAD_CANCEL_DEFERRED;
}
libc_hidden_def (__pthread_disable_asynccancel)
+
+void
+__do_cancel (void)
+{
+ __exit_thread (PTHREAD_CANCELED);
+}
diff --git a/nptl/pthread_cancel.c b/nptl/pthread_cancel.c
index a8aa3b3d15..868cf676a3 100644
--- a/nptl/pthread_cancel.c
+++ b/nptl/pthread_cancel.c
@@ -107,7 +107,6 @@ __pthread_cancel (pthread_t th)
__libc_multiple_threads = 1;
#endif
- THREAD_SETMEM (pd, result, PTHREAD_CANCELED);
if (pd->cancelstate == PTHREAD_CANCEL_ENABLE
&& pd->canceltype == PTHREAD_CANCEL_ASYNCHRONOUS)
__do_cancel ();
diff --git a/nptl/pthread_exit.c b/nptl/pthread_exit.c
index f54388a8e2..14a73043bf 100644
--- a/nptl/pthread_exit.c
+++ b/nptl/pthread_exit.c
@@ -31,9 +31,7 @@ __pthread_exit (void *value)
" must be installed for pthread_exit to work\n");
}
- THREAD_SETMEM (THREAD_SELF, result, value);
-
- __do_cancel ();
+ __exit_thread (value);
}
libc_hidden_def (__pthread_exit)
weak_alias (__pthread_exit, pthread_exit)
diff --git a/nptl/pthread_testcancel.c b/nptl/pthread_testcancel.c
index 7a7a199b6d..6c613462ab 100644
--- a/nptl/pthread_testcancel.c
+++ b/nptl/pthread_testcancel.c
@@ -29,7 +29,6 @@ ___pthread_testcancel (void)
&& !(cancelhandling & EXITING_BITMASK)
&& !(cancelhandling & TERMINATED_BITMASK))
{
- THREAD_SETMEM (self, result, PTHREAD_CANCELED);
__do_cancel ();
}
}
diff --git a/nptl/tst-cleanup5.c b/nptl/tst-cleanup5.c
new file mode 100644
index 0000000000..f1f81a40fe
--- /dev/null
+++ b/nptl/tst-cleanup5.c
@@ -0,0 +1,129 @@
+/* Check if cancellation state and type is correctly set on thread exit.
+ 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 <support/check.h>
+#include <support/xthread.h>
+#include <support/xunistd.h>
+
+static int pipefds[2];
+static pthread_barrier_t b;
+
+static void
+clh (void *arg)
+{
+ /* Although POSIX state setting either the cancellation state or type is
+ undefined during cleanup handler execution, both calls should be safe
+ since none has any side-effect (they should not change current state
+ neither trigger a pending cancellation). */
+
+ int state;
+ TEST_VERIFY (pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &state) == 0);
+ TEST_COMPARE (state, PTHREAD_CANCEL_DISABLE);
+
+ int type;
+ TEST_VERIFY (pthread_setcanceltype (PTHREAD_CANCEL_DEFERRED, &type) == 0);
+ TEST_COMPARE (type, PTHREAD_CANCEL_DEFERRED);
+}
+
+/* Check if a thread with PTHREAD_CANCEL_DEFERRED cancellation on
+ pthread_cleanup_pop sets the correct state and type as pthread_exit. */
+static void *
+tf_cancel_deferred (void *arg)
+{
+ xpthread_barrier_wait (&b);
+
+ pthread_cleanup_push (clh, NULL);
+
+ char c;
+ read (pipefds[0], &c, 1);
+
+ pthread_cleanup_pop (1);
+
+ return NULL;
+}
+
+/* Check if a thread with PTHREAD_CANCEL_DEFERRED cancellation on
+ blocked read() sets the correct state and type as pthread_exit. */
+static void *
+tf_testcancel (void *arg)
+{
+ xpthread_barrier_wait (&b);
+
+ pthread_cleanup_push (clh, NULL);
+
+ char c;
+ read (pipefds[0], &c, 1);
+
+ pthread_testcancel ();
+
+ pthread_cleanup_pop (1);
+
+ return NULL;
+}
+
+#define EXIT_EXPECTED_VALUE ((void *) 42)
+
+/* Check if a thread with PTHREAD_CANCEL_DEFERRED cancellation on
+ pthread_exit() sets the correct state and type. */
+static void *
+tf_exit (void *arg)
+{
+ xpthread_barrier_wait (&b);
+
+ pthread_cleanup_push (clh, NULL);
+
+ pthread_exit (EXIT_EXPECTED_VALUE);
+
+ pthread_cleanup_pop (1);
+
+ return NULL;
+}
+
+static int
+do_test (void)
+{
+ xpipe (pipefds);
+
+ xpthread_barrier_init (&b, NULL, 2);
+ {
+ pthread_t th = xpthread_create (NULL, tf_cancel_deferred, NULL);
+ xpthread_barrier_wait (&b);
+ xpthread_cancel (th);
+ void *r = xpthread_join (th);
+ TEST_VERIFY (r == PTHREAD_CANCELED);
+ }
+
+ {
+ pthread_t th = xpthread_create (NULL, tf_testcancel, NULL);
+ xpthread_barrier_wait (&b);
+ xpthread_cancel (th);
+ void *r = xpthread_join (th);
+ TEST_VERIFY (r == PTHREAD_CANCELED);
+ }
+
+ {
+ pthread_t th = xpthread_create (NULL, tf_exit, NULL);
+ xpthread_barrier_wait (&b);
+ void *r = xpthread_join (th);
+ TEST_VERIFY (r == EXIT_EXPECTED_VALUE);
+ }
+
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/nptl/pthreadP.h b/sysdeps/nptl/pthreadP.h
index 0e39afecc6..aebddb361b 100644
--- a/sysdeps/nptl/pthreadP.h
+++ b/sysdeps/nptl/pthreadP.h
@@ -267,20 +267,30 @@ extern void __pthread_unregister_cancel (__pthread_unwind_buf_t *__buf)
__cleanup_fct_attribute;
libc_hidden_proto (__pthread_unregister_cancel)
-/* Called when a thread reacts on a cancellation request. */
-static inline void
-__attribute ((noreturn, always_inline))
-__do_cancel (void)
+static _Noreturn inline void
+__exit_thread (void *value)
{
struct pthread *self = THREAD_SELF;
/* Make sure we get no more cancellations. */
THREAD_ATOMIC_BIT_SET (self, cancelhandling, EXITING_BIT);
+ THREAD_SETMEM (self, result, value);
+
+ /* It is required by POSIX XSH 2.9.5 Thread Cancellation under the heading
+ Thread Cancellation Cleanup Handlers and also avoid further cancellation
+ wrapper to act on cancellation. */
+ THREAD_SETMEM (self, cancelstate, PTHREAD_CANCEL_DISABLE);
+ THREAD_SETMEM (self, canceltype, PTHREAD_CANCEL_DEFERRED);
+
__pthread_unwind ((__pthread_unwind_buf_t *)
THREAD_GETMEM (self, cleanup_jmp_buf));
}
+/* It is a wrapper over __exit_thread (PTHREAD_CANCELED). It is has its own
+ implementation because it might be called by arch-specific asm code. */
+_Noreturn void __do_cancel (void) attribute_hidden;
+
/* Internal prototypes. */
--
2.30.2
next prev parent reply other threads:[~2021-09-30 20:00 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-30 20:00 [PATCH 00/15] Fix various NPTL synchronization issues Adhemerval Zanella
2021-09-30 20:00 ` Adhemerval Zanella [this message]
2021-09-30 20:00 ` [PATCH 02/15] nptl: Handle robust PI mutexes for !__ASSUME_SET_ROBUST_LIST (BZ #28268) Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 03/15] nptl: Do not use pthread set_tid_address as state synchronization (BZ #19951) Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 04/15] nptl: Move setxid flag out of cancelhandling Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 05/15] nptl: Replace struct thread cancelhandling field Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 06/15] nptl: Use exit_lock when accessing TID on pthread_getaffinity_np Adhemerval Zanella
2021-09-30 20:54 ` Florian Weimer
2021-10-04 12:45 ` Cyril Hrubis
2021-10-04 19:27 ` Florian Weimer
2021-10-04 19:53 ` Adhemerval Zanella
2021-10-05 7:35 ` Cyril Hrubis
2021-10-05 13:47 ` Adhemerval Zanella
2021-10-10 14:37 ` Florian Weimer
2021-09-30 20:00 ` [PATCH 07/15] nptl: Use exit_lock when accessing TID on pthread_setaffinity Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 08/15] nptl: Use exit_lock when accessing TID on pthread_getcpuclockid Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 09/15] nptl: Use exit_lock when accessing TID on pthread_setschedparam Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 10/15] nptl: Use exit_lock when accessing TID on pthread_getschedparam Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 11/15] nptl: Use exit_lock when accessing TID on pthread_getname_np Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 12/15] nptl: Use exit_lock when accessing TID on pthread_setname_np Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 13/15] nptl: Use exit_lock when accessing TID on pthread_sigqueue Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 14/15] nptl: Use exit_lock when accessing TID on pthread_setschedprio Adhemerval Zanella
2021-09-30 20:00 ` [PATCH 15/15] nptl: Remove INVALID_TD_P Adhemerval Zanella
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210930200051.1017457-2-adhemerval.zanella@linaro.org \
--to=adhemerval.zanella@linaro.org \
--cc=libc-alpha@sourceware.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).