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authorUlrich Drepper <drepper@redhat.com>2004-03-24 06:36:06 +0000
committerUlrich Drepper <drepper@redhat.com>2004-03-24 06:36:06 +0000
commit2c0b891afe29dd28d0e6d75e0da8681db7fd100d (patch)
tree06fead8fc58acefbe9a9ebe353f0d596e73522ad /nptl/pthread_mutex_lock.c
parent565699e492f741bc4563c73046f457924c6f708a (diff)
downloadglibc-2c0b891afe29dd28d0e6d75e0da8681db7fd100d.tar.gz
Update.
* sysdeps/unix/sysv/linux/smp.h: New file. * sysdeps/unix/sysv/linux/sh/smp.h: New file. * init.c: Define __is_smp. (__pthread_initialize_minimal_internal): Call is_smp_system to initialize __is_smp. * pthreadP.h: Declare __is_smp. Define MAX_ADAPTIVE_COUNT is necessary. * pthread_mutex_init.c: Add comment regarding __spins field. * pthread_mutex_lock.c: Implement adaptive mutex type. * pthread_mutex_timedlock.c: Likewise. * sysdeps/unix/sysv/linux/pthread_mutex_cond_lock.c: Likewise. * sysdeps/unix/sysv/linux/alpha/bits/pthreadtypes.h (pthread_mutex_t): Add __spins field. * sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/ia64/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/sh/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/sparc/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/x86_64/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/alpha/bits/pthreadtypes.h: Define lll_mutex_cond_trylock. * sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/sh/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/sparc/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h: Likewise. Define BUSY_WAIT_NOP. * sysdeps/unix/sysv/linux/ia64/bits/pthreadtypes.h: Likewise. * sysdeps/unix/sysv/linux/x86_64/bits/pthreadtypes.h: Likewise. * tst-mutex5.c: Add support for testing adaptive mutexes. * tst-mutex7.c: Likewise. * tst-mutex5a.c: New file. * tst-mutex7a.c: New file. * Makefile (tests): Add tst-mutex5a and tst-mutex7a.
Diffstat (limited to 'nptl/pthread_mutex_lock.c')
-rw-r--r--nptl/pthread_mutex_lock.c34
1 files changed, 32 insertions, 2 deletions
diff --git a/nptl/pthread_mutex_lock.c b/nptl/pthread_mutex_lock.c
index ac770c5c00..ee39f20820 100644
--- a/nptl/pthread_mutex_lock.c
+++ b/nptl/pthread_mutex_lock.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
@@ -25,6 +25,7 @@
#ifndef LLL_MUTEX_LOCK
# define LLL_MUTEX_LOCK(mutex) lll_mutex_lock (mutex)
+# define LLL_MUTEX_TRYLOCK(mutex) lll_mutex_trylock (mutex)
#endif
@@ -32,6 +33,8 @@ int
__pthread_mutex_lock (mutex)
pthread_mutex_t *mutex;
{
+ assert (sizeof (mutex->__size) >= sizeof (mutex->__data));
+
pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
switch (__builtin_expect (mutex->__data.__kind, PTHREAD_MUTEX_TIMED_NP))
@@ -68,10 +71,37 @@ __pthread_mutex_lock (mutex)
default:
/* Correct code cannot set any other type. */
case PTHREAD_MUTEX_TIMED_NP:
- case PTHREAD_MUTEX_ADAPTIVE_NP:
+ simple:
/* Normal mutex. */
LLL_MUTEX_LOCK (mutex->__data.__lock);
break;
+
+ case PTHREAD_MUTEX_ADAPTIVE_NP:
+ if (! __is_smp)
+ goto simple;
+
+ if (LLL_MUTEX_TRYLOCK (mutex->__data.__lock) != 0)
+ {
+ int cnt = 0;
+ int max_cnt = MIN (MAX_ADAPTIVE_COUNT,
+ mutex->__data.__spins * 2 + 10);
+ do
+ {
+ if (cnt++ >= max_cnt)
+ {
+ LLL_MUTEX_LOCK (mutex->__data.__lock);
+ break;
+ }
+
+#ifdef BUSY_WAIT_NOP
+ BUSY_WAIT_NOP;
+#endif
+ }
+ while (LLL_MUTEX_TRYLOCK (mutex->__data.__lock) != 0);
+
+ mutex->__data.__spins += (cnt - mutex->__data.__spins) / 8;
+ }
+ break;
}
/* Record the ownership. */