diff options
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h')
-rw-r--r-- | nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h index a715879dbd..e9f895d6e8 100644 --- a/nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h +++ b/nptl/sysdeps/unix/sysv/linux/powerpc/lowlevellock.h @@ -1,4 +1,4 @@ -/* Copyright (C) 2003 Free Software Foundation, Inc. +/* Copyright (C) 2003, 2004 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003. @@ -100,6 +100,21 @@ #define lll_mutex_trylock(lock) __lll_trylock (&(lock)) +/* Set *futex to 2 if it is 0, atomically. Returns the old value */ +#define lll_mutex_cond_trylock(futex) \ + ({ int __val; \ + __asm __volatile ("1: lwarx %0,0,%2\n" \ + " cmpwi 0,%0,0\n" \ + " bne 2f\n" \ + " stwcx. %3,0,%2\n" \ + " bne- 1b\n" \ + "2: " __lll_acq_instr \ + : "=&r" (__val), "=m" (*futex) \ + : "r" (futex), "r" (2), "1" (*futex) \ + : "cr0", "memory"); \ + __val; \ + }) + extern void __lll_lock_wait (int *futex) attribute_hidden; |