diff options
| -rw-r--r-- | ChangeLog | 11 | ||||
| -rw-r--r-- | sysdeps/powerpc/nptl/elide.h | 111 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h | 8 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/elision-conf.c | 3 |
4 files changed, 130 insertions, 3 deletions
diff --git a/ChangeLog b/ChangeLog index 829c7ec74a..6737953b3c 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,16 @@ 2014-01-12 Adhemerval Zanella <azanella@linux.vnet.ibm.com> + * sysdeps/powerpc/nptl/elide.h: New file: generic lock elision support + for powerpc. + * sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h + [pthread_rwlock_t] (__pad1): Change size to 7 bytes in 64 bits case + and remove it for 32 bits case. + [pthread_rwlock_t] (__rwelision): New field for lock elision. + (__PTHREAD_RWLOCK_ELISION_EXTRA): Adjust for new lock elision field + initialization. + * sysdeps/unix/sysv/linux/powerpc/elision-conf.c (elision_init): + Disable lock elision with rdlocks if elision is not available. + * sysdeps/unix/sysv/linux/powerpc/Makefile [nptl] (sysdep_routines): Add lock elision objects. * sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h diff --git a/sysdeps/powerpc/nptl/elide.h b/sysdeps/powerpc/nptl/elide.h new file mode 100644 index 0000000000..01572d99ce --- /dev/null +++ b/sysdeps/powerpc/nptl/elide.h @@ -0,0 +1,111 @@ +/* elide.h: Generic lock elision support for powerpc. + Copyright (C) 2014 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#ifndef ELIDE_PPC_H +# define ELIDE_PPC_H + +#ifdef ENABLE_LOCK_ELISION +# include <htm.h> +# include <elision-conf.h> + +/* Returns true if the lock defined by is_lock_free as elided. + ADAPT_COUNT is a pointer to per-lock state variable. */ + +static inline bool +__elide_lock (uint8_t *adapt_count, int is_lock_free) +{ + if (*adapt_count > 0) + { + (*adapt_count)--; + return false; + } + + for (int i = __elision_aconf.try_tbegin; i > 0; i--) + { + if (__builtin_tbegin (0)) + { + if (is_lock_free) + return true; + /* Lock was busy. */ + __builtin_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 (_TEXASRU_FAILURE_PERSISTENT (__builtin_get_texasru ())) + { + if (__elision_aconf.skip_lock_internal_abort > 0) + *adapt_count = __elision_aconf.skip_lock_internal_abort; + break; + } + /* Same logic as above, but for a number of temporary failures in a + a row. */ + else if (__elision_aconf.skip_lock_out_of_tbegin_retries > 0 + && __elision_aconf.try_tbegin > 0) + *adapt_count = __elision_aconf.skip_lock_out_of_tbegin_retries; + } + } + + return false; +} + +# define ELIDE_LOCK(adapt_count, is_lock_free) \ + __elide_lock (&(adapt_count), is_lock_free) + + +static inline bool +__elide_trylock (uint8_t *adapt_count, int is_lock_free, int write) +{ + if (__elision_aconf.try_tbegin > 0) + { + if (write) + __builtin_tabort (_ABORT_NESTED_TRYLOCK); + return __elide_lock (adapt_count, is_lock_free); + } + return false; +} + +# define ELIDE_TRYLOCK(adapt_count, is_lock_free, write) \ + __elide_trylock (&(adapt_count), is_lock_free, write) + + +static inline bool +__elide_unlock (int is_lock_free) +{ + if (is_lock_free) + { + __builtin_tend (0); + return true; + } + return false; +} + +# define ELIDE_UNLOCK(is_lock_free) \ + __elide_unlock (is_lock_free) + +# else + +# define ELIDE_LOCK(adapt_count, is_lock_free) 0 +# define ELIDE_TRYLOCK(adapt_count, is_lock_free, write) 0 +# define ELIDE_UNLOCK(is_lock_free) 0 + +#endif /* ENABLE_LOCK_ELISION */ + +#endif diff --git a/sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h b/sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h index 0f971cdf21..7cbdb2cb77 100644 --- a/sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h +++ b/sysdeps/unix/sysv/linux/powerpc/bits/pthreadtypes.h @@ -172,11 +172,13 @@ typedef union unsigned int __nr_writers_queued; int __writer; int __shared; - unsigned long int __pad1; + unsigned char __rwelision; + unsigned char __pad1[7]; unsigned long int __pad2; /* FLAGS must stay at this position in the structure to maintain binary compatibility. */ unsigned int __flags; +# define __PTHREAD_RWLOCK_ELISION_EXTRA 0, {0, 0, 0, 0, 0, 0, 0 } } __data; # else struct @@ -187,20 +189,20 @@ typedef union unsigned int __writer_wakeup; unsigned int __nr_readers_queued; unsigned int __nr_writers_queued; - unsigned char __pad1; + unsigned char __rwelision; unsigned char __pad2; unsigned char __shared; /* FLAGS must stay at this position in the structure to maintain binary compatibility. */ unsigned char __flags; int __writer; +#define __PTHREAD_RWLOCK_ELISION_EXTRA 0 } __data; # endif char __size[__SIZEOF_PTHREAD_RWLOCK_T]; long int __align; } pthread_rwlock_t; -#define __PTHREAD_RWLOCK_ELISION_EXTRA 0 typedef union { diff --git a/sysdeps/unix/sysv/linux/powerpc/elision-conf.c b/sysdeps/unix/sysv/linux/powerpc/elision-conf.c index 1d962e1d20..70fbbb2215 100644 --- a/sysdeps/unix/sysv/linux/powerpc/elision-conf.c +++ b/sysdeps/unix/sysv/linux/powerpc/elision-conf.c @@ -63,6 +63,9 @@ elision_init (int argc __attribute__ ((unused)), int elision_available = (GLRO (dl_hwcap2) & PPC_FEATURE2_HAS_HTM) ? 1 : 0; __pthread_force_elision = __libc_enable_secure ? 0 : elision_available; #endif + if (!__pthread_force_elision) + /* Disable elision on rwlocks. */ + __elision_aconf.try_tbegin = 0; } #ifdef SHARED |