diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/powerpc/elision-lock.c')
-rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/elision-lock.c | 43 |
1 files changed, 9 insertions, 34 deletions
diff --git a/sysdeps/unix/sysv/linux/powerpc/elision-lock.c b/sysdeps/unix/sysv/linux/powerpc/elision-lock.c index 7f9bcc2bf1..dd1e4c3b17 100644 --- a/sysdeps/unix/sysv/linux/powerpc/elision-lock.c +++ b/sysdeps/unix/sysv/linux/powerpc/elision-lock.c @@ -1,5 +1,5 @@ /* elision-lock.c: Elided pthread mutex lock. - Copyright (C) 2015 Free Software Foundation, Inc. + Copyright (C) 2015-2016 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -23,27 +23,6 @@ #include <elision-conf.h> #include "htm.h" -/* PowerISA 2.0.7 Section B.5.5 defines isync to be insufficient as a - barrier in acquire mechanism for HTM operations, a strong 'sync' is - required. */ -#undef __arch_compare_and_exchange_val_32_acq -#define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \ - ({ \ - __typeof (*(mem)) __tmp; \ - __typeof (mem) __memp = (mem); \ - __asm __volatile ( \ - "1: lwarx %0,0,%1" MUTEX_HINT_ACQ "\n" \ - " cmpw %0,%2\n" \ - " bne 2f\n" \ - " stwcx. %3,0,%1\n" \ - " bne- 1b\n" \ - "2: sync" \ - : "=&r" (__tmp) \ - : "b" (__memp), "r" (oldval), "r" (newval) \ - : "cr0", "memory"); \ - __tmp; \ - }) - #if !defined(LLL_LOCK) && !defined(EXTRAARG) /* Make sure the configuration code is always linked in for static libraries. */ @@ -68,40 +47,36 @@ __lll_lock_elision (int *lock, short *adapt_count, EXTRAARG int pshared) { if (*adapt_count > 0) { - (*adapt_count)--; goto use_lock; } - int try_begin = aconf.try_tbegin; - while (1) + for (int i = aconf.try_tbegin; i > 0; i--) { - if (__builtin_tbegin (0)) + if (__libc_tbegin (0)) { if (*lock == 0) return 0; /* Lock was busy. Fall back to normal locking. */ - __builtin_tabort (_ABORT_LOCK_BUSY); + __libc_tabort (_ABORT_LOCK_BUSY); } else { /* A persistent failure indicates that a retry will probably result in another failure. Use normal locking now and for the next couple of calls. */ - if (try_begin-- <= 0 - || _TEXASRU_FAILURE_PERSISTENT (__builtin_get_texasru ())) + if (_TEXASRU_FAILURE_PERSISTENT (__builtin_get_texasru ())) { if (aconf.skip_lock_internal_abort > 0) *adapt_count = aconf.skip_lock_internal_abort; goto use_lock; } - /* Same logic as above, but for for a number of temporary failures - in a row. */ - else if (aconf.skip_lock_out_of_tbegin_retries > 0 - && aconf.try_tbegin > 0) - *adapt_count = aconf.skip_lock_out_of_tbegin_retries; } } + /* Fall back to locks for a bit if retries have been exhausted */ + if (aconf.try_tbegin > 0 && aconf.skip_lock_out_of_tbegin_retries > 0) + *adapt_count = aconf.skip_lock_out_of_tbegin_retries; + use_lock: return LLL_LOCK ((*lock), pshared); } |