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authorJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
committerJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
commit0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (patch)
tree2ea1f8305970753e4a657acb2ccc15ca3eec8e2c /nptl/pthread_mutex_init.c
parent7d58530341304d403a6626d7f7a1913165fe2f32 (diff)
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2.5-18.1
Diffstat (limited to 'nptl/pthread_mutex_init.c')
-rw-r--r--nptl/pthread_mutex_init.c81
1 files changed, 78 insertions, 3 deletions
diff --git a/nptl/pthread_mutex_init.c b/nptl/pthread_mutex_init.c
index 074941daf3..96f1fb00f8 100644
--- a/nptl/pthread_mutex_init.c
+++ b/nptl/pthread_mutex_init.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
@@ -18,10 +18,10 @@
02111-1307 USA. */
#include <assert.h>
+#include <errno.h>
#include <string.h>
#include "pthreadP.h"
-
static const struct pthread_mutexattr default_attr =
{
/* Default is a normal mutex, not shared between processes. */
@@ -29,6 +29,11 @@ static const struct pthread_mutexattr default_attr =
};
+#ifndef __ASSUME_FUTEX_LOCK_PI
+static int tpi_supported;
+#endif
+
+
int
__pthread_mutex_init (mutex, mutexattr)
pthread_mutex_t *mutex;
@@ -40,17 +45,87 @@ __pthread_mutex_init (mutex, mutexattr)
imutexattr = (const struct pthread_mutexattr *) mutexattr ?: &default_attr;
+ /* Sanity checks. */
+ switch (__builtin_expect (imutexattr->mutexkind
+ & PTHREAD_MUTEXATTR_PROTOCOL_MASK,
+ PTHREAD_PRIO_NONE
+ << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT))
+ {
+ case PTHREAD_PRIO_NONE << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT:
+ break;
+
+ case PTHREAD_PRIO_INHERIT << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT:
+#ifndef __ASSUME_FUTEX_LOCK_PI
+ if (__builtin_expect (tpi_supported == 0, 0))
+ {
+ int lock = 0;
+ INTERNAL_SYSCALL_DECL (err);
+ int ret = INTERNAL_SYSCALL (futex, err, 4, &lock, FUTEX_UNLOCK_PI,
+ 0, 0);
+ assert (INTERNAL_SYSCALL_ERROR_P (ret, err));
+ tpi_supported = INTERNAL_SYSCALL_ERRNO (ret, err) == ENOSYS ? -1 : 1;
+ }
+ if (__builtin_expect (tpi_supported < 0, 0))
+ return ENOTSUP;
+#endif
+ break;
+
+ default:
+ /* XXX: For now we don't support robust priority protected mutexes. */
+ if (imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_ROBUST)
+ return ENOTSUP;
+ break;
+ }
+
/* Clear the whole variable. */
memset (mutex, '\0', __SIZEOF_PTHREAD_MUTEX_T);
/* Copy the values from the attribute. */
- mutex->__data.__kind = imutexattr->mutexkind & ~0x80000000;
+ mutex->__data.__kind = imutexattr->mutexkind & ~PTHREAD_MUTEXATTR_FLAG_BITS;
+
+ if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_ROBUST) != 0)
+ {
+#ifndef __ASSUME_SET_ROBUST_LIST
+ if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_PSHARED) != 0
+ && __set_robust_list_avail < 0)
+ return ENOTSUP;
+#endif
+
+ mutex->__data.__kind |= PTHREAD_MUTEX_ROBUST_NORMAL_NP;
+ }
+
+ switch (imutexattr->mutexkind & PTHREAD_MUTEXATTR_PROTOCOL_MASK)
+ {
+ case PTHREAD_PRIO_INHERIT << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT:
+ mutex->__data.__kind |= PTHREAD_MUTEX_PRIO_INHERIT_NP;
+ break;
+
+ case PTHREAD_PRIO_PROTECT << PTHREAD_MUTEXATTR_PROTOCOL_SHIFT:
+ mutex->__data.__kind |= PTHREAD_MUTEX_PRIO_PROTECT_NP;
+
+ int ceiling = (imutexattr->mutexkind
+ & PTHREAD_MUTEXATTR_PRIO_CEILING_MASK)
+ >> PTHREAD_MUTEXATTR_PRIO_CEILING_SHIFT;
+ if (! ceiling)
+ {
+ if (__sched_fifo_min_prio == -1)
+ __init_sched_fifo_prio ();
+ if (ceiling < __sched_fifo_min_prio)
+ ceiling = __sched_fifo_min_prio;
+ }
+ mutex->__data.__lock = ceiling << PTHREAD_MUTEX_PRIO_CEILING_SHIFT;
+ break;
+
+ default:
+ break;
+ }
/* Default values: mutex not used yet. */
// mutex->__count = 0; already done by memset
// mutex->__owner = 0; already done by memset
// mutex->__nusers = 0; already done by memset
// mutex->__spins = 0; already done by memset
+ // mutex->__next = NULL; already done by memset
return 0;
}