@@ -491,6 +491,7 @@ extern int __pthread_setcanceltype (int type, int *oldtype);
extern int __pthread_enable_asynccancel (void) attribute_hidden;
extern void __pthread_disable_asynccancel (int oldtype)
internal_function attribute_hidden;
+extern void __pthread_testcancel (void);
#if IS_IN (libpthread)
hidden_proto (__pthread_mutex_init)
@@ -505,6 +506,7 @@ hidden_proto (__pthread_getspecific)
hidden_proto (__pthread_setspecific)
hidden_proto (__pthread_once)
hidden_proto (__pthread_setcancelstate)
+hidden_proto (__pthread_testcancel)
#endif
extern int __pthread_cond_broadcast_2_0 (pthread_cond_2_0_t *cond);
@@ -21,7 +21,9 @@
void
-pthread_testcancel (void)
+__pthread_testcancel (void)
{
CANCELLATION_P (THREAD_SELF);
}
+strong_alias (__pthread_testcancel, pthread_testcancel)
+hidden_def (__pthread_testcancel)
@@ -30,6 +30,9 @@ sem_timedwait (sem_t *sem, const struct timespec *abstime)
return -1;
}
+ /* Check cancellation for uncontended case. */
+ __pthread_testcancel ();
+
if (__new_sem_wait_fast ((struct new_sem *) sem, 0) == 0)
return 0;
else
@@ -23,6 +23,9 @@
int
__new_sem_wait (sem_t *sem)
{
+ /* Check cancellation for uncontended case. */
+ __pthread_testcancel ();
+
if (__new_sem_wait_fast ((struct new_sem *) sem, 0) == 0)
return 0;
else
@@ -1,4 +1,5 @@
-/* Copyright (C) 2003-2016 Free Software Foundation, Inc.
+/* Test sem_wait cancellation for uncontended case.
+ Copyright (C) 2003-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
@@ -23,104 +24,101 @@
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
-
+#include <stdbool.h>
static pthread_barrier_t bar;
static sem_t sem;
-
+static int ncall;
+static volatile int thread_ret;
static void
cleanup (void *arg)
{
- static int ncall;
-
if (++ncall != 1)
{
puts ("second call to cleanup");
- exit (1);
+ thread_ret = 1;
}
-
- printf ("cleanup call #%d\n", ncall);
}
-
static void *
tf (void *arg)
{
+ thread_ret = 0;
+ ncall = 0;
+
pthread_cleanup_push (cleanup, NULL);
int e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
- puts ("tf: 1st barrier_wait failed");
- exit (1);
+ puts ("error: tf: 1st barrier_wait failed");
+ thread_ret = 1;
+ return NULL;
}
- /* This call should block and be cancelable. */
sem_wait (&sem);
pthread_cleanup_pop (0);
- puts ("sem_wait returned");
-
return NULL;
}
-
static int
do_test (void)
{
pthread_t th;
+ thread_ret = 0;
+
if (pthread_barrier_init (&bar, NULL, 2) != 0)
{
- puts ("barrier_init failed");
- exit (1);
+ puts ("error: barrier_init failed");
+ return 1;
}
+ /* A value higher than 0 will check for uncontended pthread cancellation,
+ where the sem_wait operation will return immediatelly. */
if (sem_init (&sem, 0, 1) != 0)
{
- puts ("sem_init failed");
- exit (1);
+ puts ("error: sem_init failed");
+ return 1;
}
if (pthread_create (&th, NULL, tf, NULL) != 0)
{
- puts ("create failed");
- exit (1);
+ puts ("error: create failed");
+ return 1;
}
- /* Check whether cancellation is honored even before sem_wait does
- anything. */
if (pthread_cancel (th) != 0)
{
- puts ("1st cancel failed");
- exit (1);
+ puts ("error: pthread_cancel failed");
+ return 1;
}
int e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
- puts ("1st barrier_wait failed");
- exit (1);
+ puts ("error: 1st barrier_wait failed");
+ return 1;
}
void *r;
if (pthread_join (th, &r) != 0)
{
- puts ("join failed");
- exit (1);
+ puts ("error: pthread_join failed");
+ return 1;
}
if (r != PTHREAD_CANCELED)
{
- puts ("thread not canceled");
- exit (1);
+ puts ("error: thread not canceled");
+ return 1;
}
- return 0;
+ return thread_ret;
}
-
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
@@ -1,4 +1,5 @@
-/* Copyright (C) 2003-2016 Free Software Foundation, Inc.
+/* Test sem_wait cancellation for contended case.
+ Copyright (C) 2003-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
@@ -27,6 +28,8 @@
static pthread_barrier_t bar;
static sem_t sem;
+static int ncall;
+static volatile int thread_ret;
static void
@@ -37,23 +40,24 @@ cleanup (void *arg)
if (++ncall != 1)
{
puts ("second call to cleanup");
- exit (1);
+ thread_ret = 1;
}
-
- printf ("cleanup call #%d\n", ncall);
}
-
static void *
tf (void *arg)
{
+ thread_ret = 0;
+ ncall = 0;
+
pthread_cleanup_push (cleanup, NULL);
int e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
- puts ("tf: 1st barrier_wait failed");
- exit (1);
+ puts ("error: tf: 1st barrier_wait failed");
+ thread_ret = 1;
+ return NULL;
}
/* This call should block and be cancelable. */
@@ -61,8 +65,6 @@ tf (void *arg)
pthread_cleanup_pop (0);
- puts ("sem_wait returned");
-
return NULL;
}
@@ -71,30 +73,33 @@ static int
do_test (void)
{
pthread_t th;
+ thread_ret = 0;
if (pthread_barrier_init (&bar, NULL, 2) != 0)
{
- puts ("barrier_init failed");
- exit (1);
+ puts ("error: barrier_init failed");
+ return 1;
}
+ /* A value equal to 0 will check for contended pthread cancellation,
+ where the sem_wait operation will block. */
if (sem_init (&sem, 0, 0) != 0)
{
- puts ("sem_init failed");
- exit (1);
+ puts ("error: sem_init failed");
+ return 1;
}
if (pthread_create (&th, NULL, tf, NULL) != 0)
{
- puts ("create failed");
- exit (1);
+ puts ("error: create failed");
+ return 1;
}
int e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
- puts ("1st barrier_wait failed");
- exit (1);
+ puts ("error: 1st barrier_wait failed");
+ return 1;
}
/* Give the child a chance to go to sleep in sem_wait. */
@@ -103,15 +108,15 @@ do_test (void)
/* Check whether cancellation is honored when waiting in sem_wait. */
if (pthread_cancel (th) != 0)
{
- puts ("1st cancel failed");
- exit (1);
+ puts ("error: 1st cancel failed");
+ return 1;
}
void *r;
if (pthread_join (th, &r) != 0)
{
- puts ("join failed");
- exit (1);
+ puts ("error: join failed");
+ return 1;
}
if (r != PTHREAD_CANCELED)
@@ -120,7 +125,7 @@ do_test (void)
exit (1);
}
- return 0;
+ return thread_ret;
}
@@ -1,4 +1,5 @@
-/* Copyright (C) 2003-2016 Free Software Foundation, Inc.
+/* Test sem_timedwait cancellation for uncontended case.
+ Copyright (C) 2003-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
@@ -28,33 +29,35 @@
static pthread_barrier_t bar;
static sem_t sem;
+static int ncall;
+static volatile int thread_ret;
static void
cleanup (void *arg)
{
- static int ncall;
-
if (++ncall != 1)
{
puts ("second call to cleanup");
- exit (1);
+ thread_ret = 1;
}
-
- printf ("cleanup call #%d\n", ncall);
}
static void *
tf (void *arg)
{
+ thread_ret = 0;
+ ncall = 0;
+
pthread_cleanup_push (cleanup, NULL);
int e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
puts ("tf: 1st barrier_wait failed");
- exit (1);
+ thread_ret = 1;
+ return NULL;
}
struct timeval tv;
@@ -71,8 +74,6 @@ tf (void *arg)
pthread_cleanup_pop (0);
- puts ("sem_timedwait returned");
-
return NULL;
}
@@ -82,44 +83,46 @@ do_test (void)
{
pthread_t th;
+ thread_ret = 0;
+
if (pthread_barrier_init (&bar, NULL, 2) != 0)
{
- puts ("barrier_init failed");
- exit (1);
+ puts ("error: barrier_init failed");
+ return 1;
}
if (sem_init (&sem, 0, 1) != 0)
{
- puts ("sem_init failed");
- exit (1);
+ puts ("error: sem_init failed");
+ return 1;
}
if (pthread_create (&th, NULL, tf, NULL) != 0)
{
- puts ("create failed");
- exit (1);
+ puts ("error: create failed");
+ return 1;
}
/* Check whether cancellation is honored even before sem_timedwait does
anything. */
if (pthread_cancel (th) != 0)
{
- puts ("1st cancel failed");
- exit (1);
+ puts ("error: 1st cancel failed");
+ return 1;
}
int e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
puts ("1st barrier_wait failed");
- exit (1);
+ return 1;
}
void *r;
if (pthread_join (th, &r) != 0)
{
puts ("join failed");
- exit (1);
+ return 1;
}
if (r != PTHREAD_CANCELED)
@@ -128,7 +131,7 @@ do_test (void)
exit (1);
}
- return 0;
+ return thread_ret;
}
@@ -1,4 +1,5 @@
-/* Copyright (C) 2003-2016 Free Software Foundation, Inc.
+/* Test sem_timedwait cancellation for contended case.
+ Copyright (C) 2003-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
@@ -28,26 +29,27 @@
static pthread_barrier_t bar;
static sem_t sem;
+static int ncall;
+static volatile int thread_ret;
static void
cleanup (void *arg)
{
- static int ncall;
-
if (++ncall != 1)
{
puts ("second call to cleanup");
- exit (1);
+ thread_ret = 1;
}
-
- printf ("cleanup call #%d\n", ncall);
}
static void *
tf (void *arg)
{
+ thread_ret = 0;
+ ncall = 0;
+
int e;
pthread_cleanup_push (cleanup, NULL);
@@ -55,8 +57,9 @@ tf (void *arg)
e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
- puts ("tf: 1st barrier_wait failed");
- exit (1);
+ puts ("error: tf: 1st barrier_wait failed");
+ thread_ret = 1;
+ return NULL;
}
struct timeval tv;
@@ -74,8 +77,6 @@ tf (void *arg)
pthread_cleanup_pop (0);
- printf ("sem_timedwait returned, e = %d, errno = %d\n", e, errno);
-
return NULL;
}
@@ -85,29 +86,31 @@ do_test (void)
{
pthread_t th;
+ thread_ret = 0;
+
if (pthread_barrier_init (&bar, NULL, 2) != 0)
{
- puts ("barrier_init failed");
- exit (1);
+ puts ("error: barrier_init failed");
+ return 1;
}
if (sem_init (&sem, 0, 0) != 0)
{
- puts ("sem_init failed");
- exit (1);
+ puts ("error: sem_init failed");
+ return 1;
}
if (pthread_create (&th, NULL, tf, NULL) != 0)
{
- puts ("create failed");
- exit (1);
+ puts ("error: create failed");
+ return 1;
}
int e = pthread_barrier_wait (&bar);
if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD)
{
- puts ("1st barrier_wait failed");
- exit (1);
+ puts ("error: 1st barrier_wait failed");
+ return 1;
}
/* Give the child a chance to go to sleep in sem_wait. */
@@ -116,24 +119,24 @@ do_test (void)
/* Check whether cancellation is honored when waiting in sem_timedwait. */
if (pthread_cancel (th) != 0)
{
- puts ("1st cancel failed");
- exit (1);
+ puts ("error: 1st cancel failed");
+ return 1;
}
void *r;
if (pthread_join (th, &r) != 0)
{
- puts ("join failed");
- exit (1);
+ puts ("error: join failed");
+ return 1;
}
if (r != PTHREAD_CANCELED)
{
- puts ("thread not canceled");
- exit (1);
+ puts ("error: thread not canceled");
+ return 1;
}
- return 0;
+ return thread_ret;
}
This patch fixes both sem_wait and sem_timedwait cancellation point for uncontended case. In this scenario only atomics are involved and thus the futex cancellable call is not issue and a pending cancellation signal is not handled. The fix is straighforward by calling pthread_testcancel is both function start. Although it would be simpler to call CANCELLATION_P directly, I decided to add an internal pthread_testcancel alias and use it to export less internal implementation on such function. A possible change on how pthread_testcancel is internally implemented would lead to either continue to force use CANCELLATION_P or to adjust its every use. GLIBC testcases do have tests for uncontended cases, test-cancel12 and test-cancel14.c, however both are flawed by adding another cancellation point just after thread pthread_cleanup_pop: 47 static void * 48 tf (void *arg) 49 { 50 pthread_cleanup_push (cleanup, NULL); 51 52 int e = pthread_barrier_wait (&bar); 53 if (e != 0 && e != PTHREAD_BARRIER_SERIAL_THREAD) 54 { 55 puts ("tf: 1st barrier_wait failed"); 56 exit (1); 57 } 58 59 /* This call should block and be cancelable. */ 60 sem_wait (&sem); 61 62 pthread_cleanup_pop (0); 63 64 puts ("sem_wait returned"); 65 66 return NULL; 67 } So sem_{timed}wait does not act on cancellation, pthread_cleanup_pop executes 'cleanup' and then 'puts' acts on cancellation. Since pthread_cleanup_pop removed the clean-up handler, it will ran only once and thus it won't accuse an error to indicate sem_wait has not acted on the cancellation signal. This patch also fixes this behavior by removing the cancellation point 'puts'. It also adds some cleanup on all sem_{timed}wait cancel tests, mostly to avoid calling 'exit' and some error formatting. It partially fixes BZ #18243. Checked on x86_64. [BZ #18243] * nptl/pthreadP.h (__pthread_testcancel): Add prototype and hidden_proto. * nptl/pthread_testcancel.c (pthread_cancel): Add internal aliais definition. * nptl/sem_timedwait.c (sem_timedwait): Add cancellation check for uncontended case. * nptl/sem_wait.c (__new_sem_wait): Likewise. * nptl/tst-cancel12.c (ncall): New global variable. (thread_ret): Likewise. (clean): Remove cancellation points. (tf): Fix check for uncontended case and remove exit calls. (do_test): Likewise. * nptl/tst-cancel13.c (ncall): New global variable. (thread_ret): Likewise. (clean): Remove cancellation points. (tf): Fix check for uncontended case and remove exit calls. (do_test): Likewise. * nptl/tst-cancel14.c (ncall): New global variable. (thread_ret): Likewise. (clean): Remove cancellation points. (tf): Fix check for uncontended case and remove exit calls. (do_test): Likewise. * nptl/tst-cancel15.c (ncall): New global variable. (thread_ret): Likewise. (clean): Remove cancellation points. (tf): Fix check for uncontended case and remove exit calls. (do_test): Likewise. --- nptl/pthreadP.h | 2 ++ nptl/pthread_testcancel.c | 4 ++- nptl/sem_timedwait.c | 3 +++ nptl/sem_wait.c | 3 +++ nptl/tst-cancel12.c | 64 +++++++++++++++++++++++------------------------ nptl/tst-cancel13.c | 49 ++++++++++++++++++++---------------- nptl/tst-cancel14.c | 43 ++++++++++++++++--------------- nptl/tst-cancel15.c | 53 +++++++++++++++++++++------------------ 9 files changed, 148 insertions(+), 101 deletions(-)