Module Name: src
Committed By: joerg
Date: Wed Mar 7 23:31:44 UTC 2012
Modified Files:
src/lib/libpthread: sem.c
src/tests/lib/libpthread: t_sem.c
Log Message:
Remove libpthread's semaphore implementation and always use the kernel
one. The implementation doesn't provide an async-safe sem_post and can't
without a lot of work on the pthread primitives.
Remove bogus time out requirement in test case, it should have been
a "known failure" if anything.
To generate a diff of this commit:
cvs rdiff -u -r1.21 -r1.22 src/lib/libpthread/sem.c
cvs rdiff -u -r1.5 -r1.6 src/tests/lib/libpthread/t_sem.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/libpthread/sem.c
diff -u src/lib/libpthread/sem.c:1.21 src/lib/libpthread/sem.c:1.22
--- src/lib/libpthread/sem.c:1.21 Fri Nov 14 15:49:20 2008
+++ src/lib/libpthread/sem.c Wed Mar 7 23:31:44 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: sem.c,v 1.21 2008/11/14 15:49:20 ad Exp $ */
+/* $NetBSD: sem.c,v 1.22 2012/03/07 23:31:44 joerg Exp $ */
/*-
* Copyright (c) 2003, 2006, 2007 The NetBSD Foundation, Inc.
@@ -59,7 +59,7 @@
*/
#include <sys/cdefs.h>
-__RCSID("$NetBSD: sem.c,v 1.21 2008/11/14 15:49:20 ad Exp $");
+__RCSID("$NetBSD: sem.c,v 1.22 2012/03/07 23:31:44 joerg Exp $");
#include <sys/types.h>
#include <sys/ksem.h>
@@ -71,21 +71,14 @@ __RCSID("$NetBSD: sem.c,v 1.21 2008/11/1
#include <stdarg.h>
#include "pthread.h"
-#include "pthread_int.h"
struct _sem_st {
- unsigned int usem_magic;
-#define USEM_MAGIC 0x09fa4012
+ unsigned int ksem_magic;
+#define KSEM_MAGIC 0x90af0421U
- LIST_ENTRY(_sem_st) usem_list;
- intptr_t usem_semid; /* 0 -> user (non-shared) */
-#define USEM_USER 0 /* assumes kernel does not use NULL */
- sem_t *usem_identity;
-
- /* Protects data below. */
- pthread_mutex_t usem_interlock;
- pthread_cond_t usem_cv;
- unsigned int usem_count;
+ LIST_ENTRY(_sem_st) ksem_list;
+ intptr_t ksem_semid; /* 0 -> user (non-shared) */
+ sem_t *ksem_identity;
};
static int sem_alloc(unsigned int value, intptr_t semid, sem_t *semp);
@@ -98,11 +91,7 @@ static void
sem_free(sem_t sem)
{
- if (sem->usem_semid == USEM_USER) {
- pthread_cond_destroy(&sem->usem_cv);
- pthread_mutex_destroy(&sem->usem_interlock);
- }
- sem->usem_magic = 0;
+ sem->ksem_magic = 0;
free(sem);
}
@@ -117,30 +106,25 @@ sem_alloc(unsigned int value, intptr_t s
if ((sem = malloc(sizeof(struct _sem_st))) == NULL)
return (ENOSPC);
- sem->usem_magic = USEM_MAGIC;
- pthread_mutex_init(&sem->usem_interlock, NULL);
- pthread_cond_init(&sem->usem_cv, NULL);
- sem->usem_count = value;
- sem->usem_semid = semid;
-
+ sem->ksem_magic = KSEM_MAGIC;
+ sem->ksem_semid = semid;
+
*semp = sem;
return (0);
}
+/* ARGSUSED */
int
sem_init(sem_t *sem, int pshared, unsigned int value)
{
intptr_t semid;
int error;
- semid = USEM_USER;
-
- if (pshared && _ksem_init(value, &semid) == -1)
+ if (_ksem_init(value, &semid) == -1)
return (-1);
if ((error = sem_alloc(value, semid, sem)) != 0) {
- if (semid != USEM_USER)
- _ksem_destroy(semid);
+ _ksem_destroy(semid);
errno = error;
return (-1);
}
@@ -153,24 +137,14 @@ sem_destroy(sem_t *sem)
{
#ifdef ERRORCHECK
- if (sem == NULL || *sem == NULL || (*sem)->usem_magic != USEM_MAGIC) {
+ if (sem == NULL || *sem == NULL || (*sem)->ksem_magic != KSEM_MAGIC) {
errno = EINVAL;
return (-1);
}
#endif
- if ((*sem)->usem_semid != USEM_USER) {
- if (_ksem_destroy((*sem)->usem_semid))
- return (-1);
- } else {
- pthread_mutex_lock(&(*sem)->usem_interlock);
- if (!PTQ_EMPTY(&(*sem)->usem_cv.ptc_waiters)) {
- pthread_mutex_unlock(&(*sem)->usem_interlock);
- errno = EBUSY;
- return (-1);
- }
- pthread_mutex_unlock(&(*sem)->usem_interlock);
- }
+ if (_ksem_destroy((*sem)->ksem_semid) == -1)
+ return (-1);
sem_free(*sem);
@@ -209,10 +183,10 @@ sem_open(const char *name, int oflag, ..
* if we locate one.
*/
pthread_mutex_lock(&named_sems_mtx);
- LIST_FOREACH(s, &named_sems, usem_list) {
- if (s->usem_semid == semid) {
+ LIST_FOREACH(s, &named_sems, ksem_list) {
+ if (s->ksem_semid == semid) {
pthread_mutex_unlock(&named_sems_mtx);
- return (s->usem_identity);
+ return (s->ksem_identity);
}
}
@@ -223,9 +197,9 @@ sem_open(const char *name, int oflag, ..
if ((error = sem_alloc(value, semid, sem)) != 0)
goto bad;
- LIST_INSERT_HEAD(&named_sems, *sem, usem_list);
- (*sem)->usem_identity = sem;
+ LIST_INSERT_HEAD(&named_sems, *sem, ksem_list);
pthread_mutex_unlock(&named_sems_mtx);
+ (*sem)->ksem_identity = sem;
return (sem);
@@ -246,23 +220,19 @@ sem_close(sem_t *sem)
{
#ifdef ERRORCHECK
- if (sem == NULL || *sem == NULL || (*sem)->usem_magic != USEM_MAGIC) {
+ if (sem == NULL || *sem == NULL || (*sem)->ksem_magic != KSEM_MAGIC) {
errno = EINVAL;
return (-1);
}
#endif
- if ((*sem)->usem_semid == USEM_USER) {
- errno = EINVAL;
- return (-1);
- }
-
pthread_mutex_lock(&named_sems_mtx);
- if (_ksem_close((*sem)->usem_semid) == -1) {
+ if (_ksem_close((*sem)->ksem_semid) == -1) {
pthread_mutex_unlock(&named_sems_mtx);
return (-1);
}
- LIST_REMOVE((*sem), usem_list);
+
+ LIST_REMOVE((*sem), ksem_list);
pthread_mutex_unlock(&named_sems_mtx);
sem_free(*sem);
free(sem);
@@ -279,97 +249,29 @@ sem_unlink(const char *name)
int
sem_wait(sem_t *sem)
{
- pthread_t self;
- extern int pthread__started;
#ifdef ERRORCHECK
- if (sem == NULL || *sem == NULL || (*sem)->usem_magic != USEM_MAGIC) {
+ if (sem == NULL || *sem == NULL || (*sem)->ksem_magic != KSEM_MAGIC) {
errno = EINVAL;
return (-1);
}
#endif
- self = pthread__self();
-
- if ((*sem)->usem_semid != USEM_USER) {
- pthread__testcancel(self);
- return (_ksem_wait((*sem)->usem_semid));
- }
-
- if (pthread__started == 0) {
- sigset_t set, oset;
-
- sigfillset(&set);
- (void) sigprocmask(SIG_SETMASK, &set, &oset);
- for (;;) {
- if ((*sem)->usem_count > 0) {
- break;
- }
- (void) sigsuspend(&oset);
- }
- (*sem)->usem_count--;
- (void) sigprocmask(SIG_SETMASK, &oset, NULL);
- return 0;
- }
-
- pthread_mutex_lock(&(*sem)->usem_interlock);
- for (;;) {
- if (self->pt_cancel) {
- pthread_mutex_unlock(&(*sem)->usem_interlock);
- pthread__cancelled();
- }
- if ((*sem)->usem_count > 0)
- break;
- (void)pthread_cond_wait(&(*sem)->usem_cv,
- &(*sem)->usem_interlock);
- }
- (*sem)->usem_count--;
- pthread_mutex_unlock(&(*sem)->usem_interlock);
-
- return (0);
+ return (_ksem_wait((*sem)->ksem_semid));
}
int
sem_trywait(sem_t *sem)
{
- extern int pthread__started;
#ifdef ERRORCHECK
- if (sem == NULL || *sem == NULL || (*sem)->usem_magic != USEM_MAGIC) {
+ if (sem == NULL || *sem == NULL || (*sem)->ksem_magic != KSEM_MAGIC) {
errno = EINVAL;
return (-1);
}
#endif
- if ((*sem)->usem_semid != USEM_USER)
- return (_ksem_trywait((*sem)->usem_semid));
-
- if (pthread__started == 0) {
- sigset_t set, oset;
- int rv = 0;
-
- sigfillset(&set);
- (void) sigprocmask(SIG_SETMASK, &set, &oset);
- if ((*sem)->usem_count > 0) {
- (*sem)->usem_count--;
- } else {
- errno = EAGAIN;
- rv = -1;
- }
- (void) sigprocmask(SIG_SETMASK, &oset, NULL);
- return rv;
- }
-
- pthread_mutex_lock(&(*sem)->usem_interlock);
- if ((*sem)->usem_count == 0) {
- pthread_mutex_unlock(&(*sem)->usem_interlock);
- errno = EAGAIN;
- return (-1);
- }
- (*sem)->usem_count--;
- pthread_mutex_unlock(&(*sem)->usem_interlock);
-
- return (0);
+ return (_ksem_trywait((*sem)->ksem_semid));
}
int
@@ -377,21 +279,13 @@ sem_post(sem_t *sem)
{
#ifdef ERRORCHECK
- if (sem == NULL || *sem == NULL || (*sem)->usem_magic != USEM_MAGIC) {
+ if (sem == NULL || *sem == NULL || (*sem)->ksem_magic != KSEM_MAGIC) {
errno = EINVAL;
return (-1);
}
#endif
- if ((*sem)->usem_semid != USEM_USER)
- return (_ksem_post((*sem)->usem_semid));
-
- pthread_mutex_lock(&(*sem)->usem_interlock);
- (*sem)->usem_count++;
- pthread_cond_signal(&(*sem)->usem_cv);
- pthread_mutex_unlock(&(*sem)->usem_interlock);
-
- return (0);
+ return (_ksem_post((*sem)->ksem_semid));
}
int
@@ -399,17 +293,10 @@ sem_getvalue(sem_t * __restrict sem, int
{
#ifdef ERRORCHECK
- if (sem == NULL || *sem == NULL || (*sem)->usem_magic != USEM_MAGIC) {
+ if (sem == NULL || *sem == NULL || (*sem)->ksem_magic != KSEM_MAGIC) {
errno = EINVAL;
return (-1);
}
#endif
- if ((*sem)->usem_semid != USEM_USER)
- return (_ksem_getvalue((*sem)->usem_semid, sval));
-
- pthread_mutex_lock(&(*sem)->usem_interlock);
- *sval = (int) (*sem)->usem_count;
- pthread_mutex_unlock(&(*sem)->usem_interlock);
-
- return (0);
+ return (_ksem_getvalue((*sem)->ksem_semid, sval));
}
Index: src/tests/lib/libpthread/t_sem.c
diff -u src/tests/lib/libpthread/t_sem.c:1.5 src/tests/lib/libpthread/t_sem.c:1.6
--- src/tests/lib/libpthread/t_sem.c:1.5 Wed Nov 3 16:10:22 2010
+++ src/tests/lib/libpthread/t_sem.c Wed Mar 7 23:31:44 2012
@@ -1,4 +1,4 @@
-/* $NetBSD: t_sem.c,v 1.5 2010/11/03 16:10:22 christos Exp $ */
+/* $NetBSD: t_sem.c,v 1.6 2012/03/07 23:31:44 joerg Exp $ */
/*
* Copyright (c) 2008, 2010 The NetBSD Foundation, Inc.
@@ -86,7 +86,7 @@
#include <sys/cdefs.h>
__COPYRIGHT("@(#) Copyright (c) 2008, 2010\
The NetBSD Foundation, inc. All rights reserved.");
-__RCSID("$NetBSD: t_sem.c,v 1.5 2010/11/03 16:10:22 christos Exp $");
+__RCSID("$NetBSD: t_sem.c,v 1.6 2012/03/07 23:31:44 joerg Exp $");
#include <errno.h>
#include <fcntl.h>
@@ -290,13 +290,6 @@ ATF_TC_HEAD(before_start_one_thread, tc)
}
ATF_TC_BODY(before_start_one_thread, tc)
{
- /* TODO(jmmv): This really is a race condition test. However, we can't
- * yet mark it as such because ATF does not provide such functionality.
- * Let's just mark it as an unconditional expected timeout as I haven't
- * got it to pass any single time. */
- atf_tc_expect_timeout("Race condition; it is probably unsafe to call "
- "sem_post from a signal handler when using the pthread version");
-
before_start_test(true);
}
