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GNU C Library master sources branch master updated. glibc-2.17-883-g1717da5
- From: ak at sourceware dot org
- To: glibc-cvs at sourceware dot org
- Date: 2 Jul 2013 15:47:10 -0000
- Subject: GNU C Library master sources branch master updated. glibc-2.17-883-g1717da5
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http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=1717da59aed9612becd56aaa1249aac695af4c8a
commit 1717da59aed9612becd56aaa1249aac695af4c8a
Author: Andi Kleen <ak@linux.intel.com>
Date: Thu May 16 19:17:14 2013 -0700
Add a configure option to enable lock elision and disable by default
Can be enabled with --enable-lock-elision=yes at configure time.
diff --git a/ChangeLog b/ChangeLog
index 0b37552..11fbdd2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2013-07-02 Andi Kleen <ak@linux.intel.com>
+
+ * config.h.in (ENABLE_LOCK_ELISION): Add.
+ * configure.in (--enable-lock-elision): Add option.
+ * manual/install.texi: Document --enable lock elision.
+ * configure: Regenerate
+ * INSTALL: Regenerate.
+
2013-07-02 H.J. Lu <hongjiu.lu@intel.com>
* sysdeps/i386/i686/multiarch/strcasecmp.S (__strcasecmp): Enable
diff --git a/INSTALL b/INSTALL
index a749293..f1b498a 100644
--- a/INSTALL
+++ b/INSTALL
@@ -133,6 +133,9 @@ will be used, and CFLAGS sets optimization options for the compiler.
library. This option hardcodes the newly built C library path in
dynamic tests so that they can be invoked directly.
+`--enable-lock-elision=yes'
+ Enable lock elision for pthread mutexes and rwlocks by default.
+
`--build=BUILD-SYSTEM'
`--host=HOST-SYSTEM'
These options are for cross-compiling. If you specify both
diff --git a/config.h.in b/config.h.in
index b5c6f16..6284e2a 100644
--- a/config.h.in
+++ b/config.h.in
@@ -164,6 +164,9 @@
/* Define if __stack_chk_guard canary should be randomized at program startup. */
#undef ENABLE_STACKGUARD_RANDOMIZE
+/* Define if lock elision should be enabled by default. */
+#undef ENABLE_LOCK_ELISION
+
/* Package description. */
#undef PKGVERSION
diff --git a/configure b/configure
index edde310..a873b20 100755
--- a/configure
+++ b/configure
@@ -742,6 +742,7 @@ enable_versioning
enable_oldest_abi
enable_hardcoded_path_in_tests
enable_stackguard_randomization
+enable_lock_elision
enable_add_ons
enable_hidden_plt
enable_bind_now
@@ -1399,6 +1400,9 @@ Optional Features:
--enable-stackguard-randomization
initialize __stack_chk_guard canary with a random
number at program start
+ --enable-lock-elision=yes/no
+ Enable lock elision for pthread mutexes and rwlocks
+ by default
--enable-add-ons[=DIRS...]
configure and build add-ons in DIR1,DIR2,... search
for add-ons if no parameter given
@@ -3472,6 +3476,18 @@ if test "$enable_stackguard_randomize" = yes; then
fi
+# Check whether --enable-lock-elision was given.
+if test "${enable_lock_elision+set}" = set; then :
+ enableval=$enable_lock_elision; enable_lock_elision=$enableval
+else
+ enable_lock_elision=no
+fi
+
+if test "$enable_lock_elision" = yes ; then
+ $as_echo "#define ENABLE_LOCK_ELISION 1" >>confdefs.h
+
+fi
+
# Check whether --enable-add-ons was given.
if test "${enable_add_ons+set}" = set; then :
enableval=$enable_add_ons;
diff --git a/configure.in b/configure.in
index cc065db..cf118f8 100644
--- a/configure.in
+++ b/configure.in
@@ -184,6 +184,15 @@ if test "$enable_stackguard_randomize" = yes; then
AC_DEFINE(ENABLE_STACKGUARD_RANDOMIZE)
fi
+AC_ARG_ENABLE([lock-elision],
+ AC_HELP_STRING([--enable-lock-elision[=yes/no]],
+ [Enable lock elision for pthread mutexes and rwlocks by default]),
+ [enable_lock_elision=$enableval],
+ [enable_lock_elision=no])
+if test "$enable_lock_elision" = yes ; then
+ AC_DEFINE(ENABLE_LOCK_ELISION)
+fi
+
dnl Generic infrastructure for drop-in additions to libc.
AC_ARG_ENABLE([add-ons],
AC_HELP_STRING([--enable-add-ons@<:@=DIRS...@:>@],
diff --git a/manual/install.texi b/manual/install.texi
index 96d3bef..0c05f51 100644
--- a/manual/install.texi
+++ b/manual/install.texi
@@ -160,6 +160,9 @@ By default, dynamic tests are linked to run with the installed C library.
This option hardcodes the newly built C library path in dynamic tests
so that they can be invoked directly.
+@item --enable-lock-elision=yes
+Enable lock elision for pthread mutexes by default.
+
@item --build=@var{build-system}
@itemx --host=@var{host-system}
These options are for cross-compiling. If you specify both options and
diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index d32046e..46cf308 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,3 +1,8 @@
+2013-07-02 Andi Kleen <ak@linux.intel.com>
+
+ * sysdeps/unix/sysv/linux/x86/elision-conf.c (elision_init):
+ Check ENABLE_LOCK_ELISION.
+
2013-07-02 Andi Kleen <ak@linux.intel.com>
* pthread_mutexattr_settype.c (__pthread_mutexattr_settype):
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.c b/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.c
index 6277e48..118cfa7 100644
--- a/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.c
+++ b/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.c
@@ -16,6 +16,7 @@
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
+#include "config.h"
#include <pthreadP.h>
#include <init-arch.h>
#include <elision-conf.h>
@@ -70,8 +71,10 @@ elision_init (int argc __attribute__ ((unused)),
char **environ)
{
__elision_available = HAS_RTM;
+#ifdef ENABLE_LOCK_ELISION
__pthread_force_elision = __libc_enable_secure ? 0 : __elision_available;
__rwlock_rtm_enabled = __libc_enable_secure ? 0 : __elision_available;
+#endif
}
#ifdef SHARED
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=49186d21ef2d87986bccaf0a7c45c48c91b265f3
commit 49186d21ef2d87986bccaf0a7c45c48c91b265f3
Author: Andi Kleen <ak@linux.intel.com>
Date: Thu Jun 27 11:15:06 2013 -0700
Disable elision for any pthread_mutexattr_settype call
PTHREAD_MUTEX_NORMAL requires deadlock for nesting, DEFAULT
does not. Since glibc uses the same value (0) disable elision
for any call to pthread_mutexattr_settype() with a 0 value.
This implies that a program can disable elision by doing
pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_NORMAL)
Based on a original proposal by Rich Felker.
diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index 7f82b20..d32046e 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,4 +1,9 @@
2013-07-02 Andi Kleen <ak@linux.intel.com>
+
+ * pthread_mutexattr_settype.c (__pthread_mutexattr_settype):
+ Disable elision for PTHREAD_MUTEX_DEFAULT.
+
+2013-07-02 Andi Kleen <ak@linux.intel.com>
Hongjiu Lu <hongjiu.lu@intel.com>
* pthread_mutex_lock.c
diff --git a/nptl/pthread_mutexattr_settype.c b/nptl/pthread_mutexattr_settype.c
index 7b476e9..a85cdcb 100644
--- a/nptl/pthread_mutexattr_settype.c
+++ b/nptl/pthread_mutexattr_settype.c
@@ -30,6 +30,11 @@ __pthread_mutexattr_settype (attr, kind)
if (kind < PTHREAD_MUTEX_NORMAL || kind > PTHREAD_MUTEX_ADAPTIVE_NP)
return EINVAL;
+ /* Cannot distinguish between DEFAULT and NORMAL. So any settype
+ call disables elision for now. */
+ if (kind == PTHREAD_MUTEX_DEFAULT)
+ kind |= PTHREAD_MUTEX_NO_ELISION_NP;
+
iattr = (struct pthread_mutexattr *) attr;
iattr->mutexkind = (iattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_BITS) | kind;
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=e8c659d74e011346785355eeef03b7fb6f533c61
commit e8c659d74e011346785355eeef03b7fb6f533c61
Author: Andi Kleen <ak@linux.intel.com>
Date: Sat Dec 22 01:03:04 2012 -0800
Add elision to pthread_mutex_{try,timed,un}lock
Add elision paths to the basic mutex locks.
The normal path has a check for RTM and upgrades the lock
to RTM when available. Trylocks cannot automatically upgrade,
so they check for elision every time.
We use a 4 byte value in the mutex to store the lock
elision adaptation state. This is separate from the adaptive
spin state and uses a separate field.
Condition variables currently do not support elision.
Recursive mutexes and condition variables may be supported at some point,
but are not in the current implementation. Also "trylock" will
not automatically enable elision unless some other lock call
has been already called on the lock.
This version does not use IFUNC, so it means every lock has one
additional check for elision. Benchmarking showed the overhead
to be negligible.
diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index e7495b9..7f82b20 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,4 +1,22 @@
2013-07-02 Andi Kleen <ak@linux.intel.com>
+ Hongjiu Lu <hongjiu.lu@intel.com>
+
+ * pthread_mutex_lock.c
+ (__pthread_mutex_lock): Add lock elision support.
+ * pthread_mutex_timedlock.c (pthread_mutex_timedlock): Likewise.
+ * pthread_mutex_trylock.c (__pthread_mutex_trylock): Likewise.
+ * pthread_mutex_unlock.c (__pthread_mutex_unlock_usercnt): Likewise.
+ * sysdeps/unix/sysv/linux/pthread_mutex_cond_lock.c: Likewise.
+ * sysdeps/unix/sysv/linux/x86/bits/pthreadtypes.h: Likewise.
+ * sysdeps/unix/sysv/linux/x86/Makefile: New file.
+ * sysdeps/unix/sysv/linux/x86/force-elision.h: New file
+ * sysdeps/unix/sysv/linux/x86/pthread_mutex_cond_lock.c: Likewise.
+ * sysdeps/unix/sysv/linux/x86/pthread_mutex_lock.c: Likewise.
+ * sysdeps/unix/sysv/linux/x86/pthread_mutex_timedlock.c: Likewise.
+ * sysdeps/unix/sysv/linux/x86/pthread_mutex_trylock.c: Likewise.
+ * sysdeps/unix/sysv/linux/x86/pthread_mutex_unlock.c: Likewise.
+
+2013-07-02 Andi Kleen <ak@linux.intel.com>
* tst-mutex5.c: Include config.h.
(do_test): Add checks for ENABLE_LOCK_ELISION.
diff --git a/nptl/pthreadP.h b/nptl/pthreadP.h
index e6b80bf..789bbf6 100644
--- a/nptl/pthreadP.h
+++ b/nptl/pthreadP.h
@@ -110,8 +110,10 @@ enum
#define PTHREAD_MUTEX_TYPE(m) \
((m)->__data.__kind & 127)
+/* Don't include NO_ELISION, as that type is always the same
+ as the underlying lock type. */
#define PTHREAD_MUTEX_TYPE_ELISION(m) \
- ((m)->__data.__kind & (127|PTHREAD_MUTEX_ELISION_FLAGS_NP))
+ ((m)->__data.__kind & (127|PTHREAD_MUTEX_ELISION_NP))
#if LLL_PRIVATE == 0 && LLL_SHARED == 128
# define PTHREAD_MUTEX_PSHARED(m) \
diff --git a/nptl/pthread_mutex_lock.c b/nptl/pthread_mutex_lock.c
index fbedfd7..b37f39a 100644
--- a/nptl/pthread_mutex_lock.c
+++ b/nptl/pthread_mutex_lock.c
@@ -25,6 +25,14 @@
#include <lowlevellock.h>
#include <stap-probe.h>
+#ifndef lll_lock_elision
+#define lll_lock_elision(lock, try_lock, private) ({ \
+ lll_lock (lock, private); 0; })
+#endif
+
+#ifndef lll_trylock_elision
+#define lll_trylock_elision(a,t) lll_trylock(a)
+#endif
#ifndef LLL_MUTEX_LOCK
# define LLL_MUTEX_LOCK(mutex) \
@@ -34,39 +42,60 @@
# define LLL_ROBUST_MUTEX_LOCK(mutex, id) \
lll_robust_lock ((mutex)->__data.__lock, id, \
PTHREAD_ROBUST_MUTEX_PSHARED (mutex))
+# define LLL_MUTEX_LOCK_ELISION(mutex) \
+ lll_lock_elision ((mutex)->__data.__lock, (mutex)->__data.__elision, \
+ PTHREAD_MUTEX_PSHARED (mutex))
+# define LLL_MUTEX_TRYLOCK_ELISION(mutex) \
+ lll_trylock_elision((mutex)->__data.__lock, (mutex)->__data.__elision, \
+ PTHREAD_MUTEX_PSHARED (mutex))
#endif
+#ifndef FORCE_ELISION
+#define FORCE_ELISION(m, s)
+#endif
static int __pthread_mutex_lock_full (pthread_mutex_t *mutex)
__attribute_noinline__;
-
int
__pthread_mutex_lock (mutex)
pthread_mutex_t *mutex;
{
assert (sizeof (mutex->__size) >= sizeof (mutex->__data));
- unsigned int type = PTHREAD_MUTEX_TYPE (mutex);
+ unsigned int type = PTHREAD_MUTEX_TYPE_ELISION (mutex);
LIBC_PROBE (mutex_entry, 1, mutex);
- if (__builtin_expect (type & ~PTHREAD_MUTEX_KIND_MASK_NP, 0))
+ if (__builtin_expect (type & ~(PTHREAD_MUTEX_KIND_MASK_NP
+ | PTHREAD_MUTEX_ELISION_FLAGS_NP), 0))
return __pthread_mutex_lock_full (mutex);
- pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
-
- if (__builtin_expect (type, PTHREAD_MUTEX_TIMED_NP)
- == PTHREAD_MUTEX_TIMED_NP)
+ if (__builtin_expect (type == PTHREAD_MUTEX_TIMED_NP, 1))
{
+ FORCE_ELISION (mutex, goto elision);
simple:
/* Normal mutex. */
LLL_MUTEX_LOCK (mutex);
assert (mutex->__data.__owner == 0);
}
- else if (__builtin_expect (type == PTHREAD_MUTEX_RECURSIVE_NP, 1))
+#ifdef HAVE_ELISION
+ else if (__builtin_expect (type == PTHREAD_MUTEX_TIMED_ELISION_NP, 1))
+ {
+ elision: __attribute__((unused))
+ /* This case can never happen on a system without elision,
+ as the mutex type initialization functions will not
+ allow to set the elision flags. */
+ /* Don't record owner or users for elision case. This is a
+ tail call. */
+ return LLL_MUTEX_LOCK_ELISION (mutex);
+ }
+#endif
+ else if (__builtin_expect (PTHREAD_MUTEX_TYPE (mutex)
+ == PTHREAD_MUTEX_RECURSIVE_NP, 1))
{
/* Recursive mutex. */
+ pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
/* Check whether we already hold the mutex. */
if (mutex->__data.__owner == id)
@@ -87,7 +116,8 @@ __pthread_mutex_lock (mutex)
assert (mutex->__data.__owner == 0);
mutex->__data.__count = 1;
}
- else if (__builtin_expect (type == PTHREAD_MUTEX_ADAPTIVE_NP, 1))
+ else if (__builtin_expect (PTHREAD_MUTEX_TYPE (mutex)
+ == PTHREAD_MUTEX_ADAPTIVE_NP, 1))
{
if (! __is_smp)
goto simple;
@@ -117,13 +147,16 @@ __pthread_mutex_lock (mutex)
}
else
{
- assert (type == PTHREAD_MUTEX_ERRORCHECK_NP);
+ pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
+ assert (PTHREAD_MUTEX_TYPE (mutex) == PTHREAD_MUTEX_ERRORCHECK_NP);
/* Check whether we already hold the mutex. */
if (__builtin_expect (mutex->__data.__owner == id, 0))
return EDEADLK;
goto simple;
}
+ pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
+
/* Record the ownership. */
mutex->__data.__owner = id;
#ifndef NO_INCR
diff --git a/nptl/pthread_mutex_timedlock.c b/nptl/pthread_mutex_timedlock.c
index 3a36424..689cefa 100644
--- a/nptl/pthread_mutex_timedlock.c
+++ b/nptl/pthread_mutex_timedlock.c
@@ -25,6 +25,17 @@
#include <stap-probe.h>
+#ifndef lll_timedlock_elision
+#define lll_timedlock_elision(a,dummy,b,c) lll_timedlock(a, b, c)
+#endif
+
+#ifndef lll_trylock_elision
+#define lll_trylock_elision(a,t) lll_trylock(a)
+#endif
+
+#ifndef FORCE_ELISION
+#define FORCE_ELISION(m, s)
+#endif
int
pthread_mutex_timedlock (mutex, abstime)
@@ -40,10 +51,11 @@ pthread_mutex_timedlock (mutex, abstime)
/* We must not check ABSTIME here. If the thread does not block
abstime must not be checked for a valid value. */
- switch (__builtin_expect (PTHREAD_MUTEX_TYPE (mutex),
+ switch (__builtin_expect (PTHREAD_MUTEX_TYPE_ELISION (mutex),
PTHREAD_MUTEX_TIMED_NP))
{
/* Recursive mutex. */
+ case PTHREAD_MUTEX_RECURSIVE_NP|PTHREAD_MUTEX_ELISION_NP:
case PTHREAD_MUTEX_RECURSIVE_NP:
/* Check whether we already hold the mutex. */
if (mutex->__data.__owner == id)
@@ -78,12 +90,22 @@ pthread_mutex_timedlock (mutex, abstime)
/* FALLTHROUGH */
case PTHREAD_MUTEX_TIMED_NP:
+ FORCE_ELISION (mutex, goto elision);
simple:
/* Normal mutex. */
result = lll_timedlock (mutex->__data.__lock, abstime,
PTHREAD_MUTEX_PSHARED (mutex));
break;
+ case PTHREAD_MUTEX_TIMED_ELISION_NP:
+ elision: __attribute__((unused))
+ /* Don't record ownership */
+ return lll_timedlock_elision (mutex->__data.__lock,
+ mutex->__data.__spins,
+ abstime,
+ PTHREAD_MUTEX_PSHARED (mutex));
+
+
case PTHREAD_MUTEX_ADAPTIVE_NP:
if (! __is_smp)
goto simple;
diff --git a/nptl/pthread_mutex_trylock.c b/nptl/pthread_mutex_trylock.c
index 8f5279d..600c848 100644
--- a/nptl/pthread_mutex_trylock.c
+++ b/nptl/pthread_mutex_trylock.c
@@ -22,6 +22,16 @@
#include "pthreadP.h"
#include <lowlevellock.h>
+#ifndef lll_trylock_elision
+#define lll_trylock_elision(a,t) lll_trylock(a)
+#endif
+
+#ifndef DO_ELISION
+#define DO_ELISION(m) 0
+#endif
+
+/* We don't force elision in trylock, because this can lead to inconsistent
+ lock state if the lock was actually busy. */
int
__pthread_mutex_trylock (mutex)
@@ -30,10 +40,11 @@ __pthread_mutex_trylock (mutex)
int oldval;
pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
- switch (__builtin_expect (PTHREAD_MUTEX_TYPE (mutex),
+ switch (__builtin_expect (PTHREAD_MUTEX_TYPE_ELISION (mutex),
PTHREAD_MUTEX_TIMED_NP))
{
/* Recursive mutex. */
+ case PTHREAD_MUTEX_RECURSIVE_NP|PTHREAD_MUTEX_ELISION_NP:
case PTHREAD_MUTEX_RECURSIVE_NP:
/* Check whether we already hold the mutex. */
if (mutex->__data.__owner == id)
@@ -57,10 +68,20 @@ __pthread_mutex_trylock (mutex)
}
break;
- case PTHREAD_MUTEX_ERRORCHECK_NP:
+ case PTHREAD_MUTEX_TIMED_ELISION_NP:
+ elision:
+ if (lll_trylock_elision (mutex->__data.__lock,
+ mutex->__data.__elision) != 0)
+ break;
+ /* Don't record the ownership. */
+ return 0;
+
case PTHREAD_MUTEX_TIMED_NP:
+ if (DO_ELISION (mutex))
+ goto elision;
+ /*FALL THROUGH*/
case PTHREAD_MUTEX_ADAPTIVE_NP:
- /* Normal mutex. */
+ case PTHREAD_MUTEX_ERRORCHECK_NP:
if (lll_trylock (mutex->__data.__lock) != 0)
break;
@@ -378,4 +399,9 @@ __pthread_mutex_trylock (mutex)
return EBUSY;
}
+
+#ifndef __pthread_mutex_trylock
+#ifndef pthread_mutex_trylock
strong_alias (__pthread_mutex_trylock, pthread_mutex_trylock)
+#endif
+#endif
diff --git a/nptl/pthread_mutex_unlock.c b/nptl/pthread_mutex_unlock.c
index c0249f7..6914503 100644
--- a/nptl/pthread_mutex_unlock.c
+++ b/nptl/pthread_mutex_unlock.c
@@ -23,6 +23,10 @@
#include <lowlevellock.h>
#include <stap-probe.h>
+#ifndef lll_unlock_elision
+#define lll_unlock_elision(a,b) ({ lll_unlock (a,b); 0; })
+#endif
+
static int
internal_function
__pthread_mutex_unlock_full (pthread_mutex_t *mutex, int decr)
@@ -34,8 +38,9 @@ __pthread_mutex_unlock_usercnt (mutex, decr)
pthread_mutex_t *mutex;
int decr;
{
- int type = PTHREAD_MUTEX_TYPE (mutex);
- if (__builtin_expect (type & ~PTHREAD_MUTEX_KIND_MASK_NP, 0))
+ int type = PTHREAD_MUTEX_TYPE_ELISION (mutex);
+ if (__builtin_expect (type &
+ ~(PTHREAD_MUTEX_KIND_MASK_NP|PTHREAD_MUTEX_ELISION_FLAGS_NP), 0))
return __pthread_mutex_unlock_full (mutex, decr);
if (__builtin_expect (type, PTHREAD_MUTEX_TIMED_NP)
@@ -55,7 +60,14 @@ __pthread_mutex_unlock_usercnt (mutex, decr)
return 0;
}
- else if (__builtin_expect (type == PTHREAD_MUTEX_RECURSIVE_NP, 1))
+ else if (__builtin_expect (type == PTHREAD_MUTEX_TIMED_ELISION_NP, 1))
+ {
+ /* Don't reset the owner/users fields for elision. */
+ return lll_unlock_elision (mutex->__data.__lock,
+ PTHREAD_MUTEX_PSHARED (mutex));
+ }
+ else if (__builtin_expect (PTHREAD_MUTEX_TYPE (mutex)
+ == PTHREAD_MUTEX_RECURSIVE_NP, 1))
{
/* Recursive mutex. */
if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
@@ -66,7 +78,8 @@ __pthread_mutex_unlock_usercnt (mutex, decr)
return 0;
goto normal;
}
- else if (__builtin_expect (type == PTHREAD_MUTEX_ADAPTIVE_NP, 1))
+ else if (__builtin_expect (PTHREAD_MUTEX_TYPE (mutex)
+ == PTHREAD_MUTEX_ADAPTIVE_NP, 1))
goto normal;
else
{
diff --git a/nptl/sysdeps/unix/sysv/linux/pthread_mutex_cond_lock.c b/nptl/sysdeps/unix/sysv/linux/pthread_mutex_cond_lock.c
index b417da5..7b6fbc1 100644
--- a/nptl/sysdeps/unix/sysv/linux/pthread_mutex_cond_lock.c
+++ b/nptl/sysdeps/unix/sysv/linux/pthread_mutex_cond_lock.c
@@ -2,8 +2,15 @@
#define LLL_MUTEX_LOCK(mutex) \
lll_cond_lock ((mutex)->__data.__lock, PTHREAD_MUTEX_PSHARED (mutex))
+
+/* Not actually elided so far. Needed? */
+#define LLL_MUTEX_LOCK_ELISION(mutex) \
+ ({ lll_cond_lock ((mutex)->__data.__lock, PTHREAD_MUTEX_PSHARED (mutex)); 0; })
+
#define LLL_MUTEX_TRYLOCK(mutex) \
lll_cond_trylock ((mutex)->__data.__lock)
+#define LLL_MUTEX_TRYLOCK_ELISION(mutex) LLL_MUTEX_TRYLOCK(mutex)
+
#define LLL_ROBUST_MUTEX_LOCK(mutex, id) \
lll_robust_cond_lock ((mutex)->__data.__lock, id, \
PTHREAD_ROBUST_MUTEX_PSHARED (mutex))
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/x86/bits/pthreadtypes.h
index ccd896c..1852e07 100644
--- a/nptl/sysdeps/unix/sysv/linux/x86/bits/pthreadtypes.h
+++ b/nptl/sysdeps/unix/sysv/linux/x86/bits/pthreadtypes.h
@@ -101,14 +101,23 @@ typedef union
binary compatibility. */
int __kind;
#ifdef __x86_64__
- int __spins;
+ short __spins;
+ short __elision;
__pthread_list_t __list;
# define __PTHREAD_MUTEX_HAVE_PREV 1
+# define __PTHREAD_MUTEX_HAVE_ELISION 1
#else
unsigned int __nusers;
__extension__ union
{
- int __spins;
+ struct
+ {
+ short __espins;
+ short __elision;
+# define __spins d.__espins
+# define __elision d.__elision
+# define __PTHREAD_MUTEX_HAVE_ELISION 2
+ } d;
__pthread_slist_t __list;
};
#endif
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c b/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c
index 2939fc9..689a6fb 100644
--- a/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c
+++ b/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c
@@ -24,9 +24,8 @@
#define aconf __elision_aconf
-/* Try to elide a futex trylock. FUTEX is the futex variable. TRY_LOCK is the
- adaptation counter in the mutex. UPGRADED is != 0 when this is for an
- automatically upgraded lock. */
+/* Try to elide a futex trylock. FUTEX is the futex variable. ADAPT_COUNT is the
+ adaptation counter in the mutex. */
int
__lll_trylock_elision (int *futex, short *adapt_count)
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/force-elision.h b/nptl/sysdeps/unix/sysv/linux/x86/force-elision.h
new file mode 100644
index 0000000..703e930
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/force-elision.h
@@ -0,0 +1,31 @@
+/* force-elision.h: Automatic enabling of elision for mutexes
+ Copyright (C) 2013 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/>. */
+
+/* Check for elision on this lock without upgrading. */
+#define DO_ELISION(m) \
+ (__pthread_force_elision \
+ && (m->__data.__kind & PTHREAD_MUTEX_NO_ELISION_NP) == 0) \
+
+/* Automatically enable elision for existing user lock kinds. */
+#define FORCE_ELISION(m, s) \
+ if (__pthread_force_elision \
+ && (m->__data.__kind & PTHREAD_MUTEX_ELISION_FLAGS_NP) == 0) \
+ { \
+ mutex->__data.__kind |= PTHREAD_MUTEX_ELISION_NP; \
+ s; \
+ }
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_cond_lock.c b/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_cond_lock.c
new file mode 100644
index 0000000..962f101
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_cond_lock.c
@@ -0,0 +1,21 @@
+/* Copyright (C) 2013 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/>. */
+
+/* The cond lock is not actually elided yet, but we still need to handle
+ already elided locks. */
+#include <elision-conf.h>
+#include "sysdeps/unix/sysv/linux/pthread_mutex_cond_lock.c"
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_lock.c b/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_lock.c
new file mode 100644
index 0000000..e639460
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_lock.c
@@ -0,0 +1,21 @@
+/* Elided version of pthread_mutex_lock.
+ Copyright (C) 2011, 2012, 2013 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/>. */
+#include <elision-conf.h>
+#include "force-elision.h"
+
+#include "nptl/pthread_mutex_lock.c"
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_timedlock.c b/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_timedlock.c
new file mode 100644
index 0000000..5115d03
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_timedlock.c
@@ -0,0 +1,20 @@
+/* Elided version of pthread_mutex_timedlock.
+ Copyright (C) 2011, 2012, 2013 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/>. */
+#include <elision-conf.h>
+#include "force-elision.h"
+#include "nptl/pthread_mutex_timedlock.c"
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_trylock.c b/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_trylock.c
new file mode 100644
index 0000000..9bb4a65
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_trylock.c
@@ -0,0 +1,21 @@
+/* Elided version of pthread_mutex_trylock.
+ Copyright (C) 2011, 2012, 2013 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/>. */
+#include <elision-conf.h>
+#include "force-elision.h"
+
+#include "nptl/pthread_mutex_trylock.c"
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=68cc29355f3334c7ad18f648ff9a6383a0916d23
commit 68cc29355f3334c7ad18f648ff9a6383a0916d23
Author: Andi Kleen <ak@linux.intel.com>
Date: Fri Jun 28 05:19:37 2013 -0700
Add minimal test suite changes for elision enabled kernels
tst-mutex5 and 8 test some behaviour not required by POSIX,
that elision changes. This changes these tests to not check
this when elision is enabled at configure time.
diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index 97ff785..e7495b9 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,5 +1,13 @@
2013-07-02 Andi Kleen <ak@linux.intel.com>
+ * tst-mutex5.c: Include config.h.
+ (do_test): Add checks for ENABLE_LOCK_ELISION.
+ * tst-mutex8.c: Include config.h
+ (tf): Add checks for ENABLE_LOCK_ELISION.
+ (check_type): Likewise.
+
+2013-07-02 Andi Kleen <ak@linux.intel.com>
+
* pthreadP.h: Add elision types.
(PTHREAD_MUTEX_TYPE_ELISION): Add.
* sysdeps/pthread/pthread.h: Add elision initializers.
diff --git a/nptl/tst-mutex5.c b/nptl/tst-mutex5.c
index f19cd8c..c223f67 100644
--- a/nptl/tst-mutex5.c
+++ b/nptl/tst-mutex5.c
@@ -22,6 +22,7 @@
#include <time.h>
#include <unistd.h>
#include <sys/time.h>
+#include <config.h>
#ifndef TYPE
@@ -85,6 +86,8 @@ do_test (void)
return 1;
}
+ /* Elided locks do not time out. */
+#ifdef ENABLE_LOCK_ELISION
if (pthread_mutex_trylock (&m) == 0)
{
puts ("mutex_trylock succeeded");
@@ -180,6 +183,7 @@ do_test (void)
puts ("3rd timedlock didn't return right away");
return 1;
}
+#endif
if (pthread_mutex_unlock (&m) != 0)
{
diff --git a/nptl/tst-mutex8.c b/nptl/tst-mutex8.c
index 2089c50..d2307e4 100644
--- a/nptl/tst-mutex8.c
+++ b/nptl/tst-mutex8.c
@@ -93,6 +93,8 @@ tf (void *arg)
static int
check_type (const char *mas, pthread_mutexattr_t *ma)
{
+ int e __attribute__((unused));
+
if (pthread_mutex_init (m, ma) != 0)
{
printf ("1st mutex_init failed for %s\n", mas);
@@ -117,7 +119,10 @@ check_type (const char *mas, pthread_mutexattr_t *ma)
return 1;
}
- int e = pthread_mutex_destroy (m);
+ /* Elided mutexes don't fail destroy. If elision is not explicitly disabled
+ we don't know, so can also not check this. */
+#ifndef ENABLE_LOCK_ELISION
+ e = pthread_mutex_destroy (m);
if (e == 0)
{
printf ("mutex_destroy of self-locked mutex succeeded for %s\n", mas);
@@ -129,6 +134,7 @@ check_type (const char *mas, pthread_mutexattr_t *ma)
mas);
return 1;
}
+#endif
if (pthread_mutex_unlock (m) != 0)
{
@@ -142,6 +148,8 @@ check_type (const char *mas, pthread_mutexattr_t *ma)
return 1;
}
+ /* Elided mutexes don't fail destroy. */
+#ifndef ENABLE_LOCK_ELISION
e = pthread_mutex_destroy (m);
if (e == 0)
{
@@ -155,6 +163,7 @@ mutex_destroy of self-trylocked mutex did not return EBUSY %s\n",
mas);
return 1;
}
+#endif
if (pthread_mutex_unlock (m) != 0)
{
@@ -189,6 +198,8 @@ mutex_destroy of self-trylocked mutex did not return EBUSY %s\n",
return 1;
}
+ /* Elided mutexes don't fail destroy. */
+#ifndef ENABLE_LOCK_ELISION
e = pthread_mutex_destroy (m);
if (e == 0)
{
@@ -201,6 +212,7 @@ mutex_destroy of self-trylocked mutex did not return EBUSY %s\n",
mutex_destroy of condvar-used mutex did not return EBUSY for %s\n", mas);
return 1;
}
+#endif
done = true;
if (pthread_cond_signal (&c) != 0)
@@ -259,6 +271,8 @@ mutex_destroy of condvar-used mutex did not return EBUSY for %s\n", mas);
return 1;
}
+ /* Elided mutexes don't fail destroy. */
+#ifndef ENABLE_LOCK_ELISION
e = pthread_mutex_destroy (m);
if (e == 0)
{
@@ -273,6 +287,7 @@ mutex_destroy of condvar-used mutex did not return EBUSY for %s\n", mas);
mas);
return 1;
}
+#endif
if (pthread_cancel (th) != 0)
{
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=b023e4ca99f5e81f90d87d23cd267ef2abd2388c
commit b023e4ca99f5e81f90d87d23cd267ef2abd2388c
Author: Andi Kleen <ak@linux.intel.com>
Date: Sat Dec 22 00:58:34 2012 -0800
Add new internal mutex type flags for elision.
Add Enable/disable flags used internally
Extend the mutex initializers to have the fields needed for
elision. The layout stays the same, and this is not visible
to programs.
These changes are not exposed outside pthread
diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index d5eb9ea..97ff785 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,4 +1,13 @@
2013-07-02 Andi Kleen <ak@linux.intel.com>
+
+ * pthreadP.h: Add elision types.
+ (PTHREAD_MUTEX_TYPE_ELISION): Add.
+ * sysdeps/pthread/pthread.h: Add elision initializers.
+ (PTHREAD_MUTEX_ELISION_NP, PTHREAD_MUTEX_NO_ELISION_NP,
+ PTHREAD_MUTEX_PSHARED_NP): Add new flags.
+ (__PTHREAD_SPINS): Add.
+
+2013-07-02 Andi Kleen <ak@linux.intel.com>
Hongjiu Lu <hongjiu.lu@intel.com>
* sysdeps/unix/sysv/linux/i386/lowlevellock.h (__lll_timedwait_tid,
diff --git a/nptl/pthreadP.h b/nptl/pthreadP.h
index 7883fdf..e6b80bf 100644
--- a/nptl/pthreadP.h
+++ b/nptl/pthreadP.h
@@ -61,6 +61,10 @@
enum
{
PTHREAD_MUTEX_KIND_MASK_NP = 3,
+
+ PTHREAD_MUTEX_ELISION_NP = 256,
+ PTHREAD_MUTEX_NO_ELISION_NP = 512,
+
PTHREAD_MUTEX_ROBUST_NORMAL_NP = 16,
PTHREAD_MUTEX_ROBUST_RECURSIVE_NP
= PTHREAD_MUTEX_ROBUST_NORMAL_NP | PTHREAD_MUTEX_RECURSIVE_NP,
@@ -93,12 +97,21 @@ enum
PTHREAD_MUTEX_PP_ERRORCHECK_NP
= PTHREAD_MUTEX_PRIO_PROTECT_NP | PTHREAD_MUTEX_ERRORCHECK_NP,
PTHREAD_MUTEX_PP_ADAPTIVE_NP
- = PTHREAD_MUTEX_PRIO_PROTECT_NP | PTHREAD_MUTEX_ADAPTIVE_NP
+ = PTHREAD_MUTEX_PRIO_PROTECT_NP | PTHREAD_MUTEX_ADAPTIVE_NP,
+ PTHREAD_MUTEX_ELISION_FLAGS_NP
+ = PTHREAD_MUTEX_ELISION_NP | PTHREAD_MUTEX_NO_ELISION_NP,
+
+ PTHREAD_MUTEX_TIMED_ELISION_NP =
+ PTHREAD_MUTEX_TIMED_NP | PTHREAD_MUTEX_ELISION_NP,
+ PTHREAD_MUTEX_TIMED_NO_ELISION_NP =
+ PTHREAD_MUTEX_TIMED_NP | PTHREAD_MUTEX_NO_ELISION_NP,
};
#define PTHREAD_MUTEX_PSHARED_BIT 128
#define PTHREAD_MUTEX_TYPE(m) \
((m)->__data.__kind & 127)
+#define PTHREAD_MUTEX_TYPE_ELISION(m) \
+ ((m)->__data.__kind & (127|PTHREAD_MUTEX_ELISION_FLAGS_NP))
#if LLL_PRIVATE == 0 && LLL_SHARED == 128
# define PTHREAD_MUTEX_PSHARED(m) \
diff --git a/nptl/sysdeps/pthread/pthread.h b/nptl/sysdeps/pthread/pthread.h
index ded5ae5..61d5346 100644
--- a/nptl/sysdeps/pthread/pthread.h
+++ b/nptl/sysdeps/pthread/pthread.h
@@ -83,27 +83,39 @@ enum
/* Mutex initializers. */
+#if __PTHREAD_MUTEX_HAVE_ELISION == 1 /* 64bit layout. */
+#define __PTHREAD_SPINS 0, 0
+#elif __PTHREAD_MUTEX_HAVE_ELISION == 2 /* 32bit layout. */
+#define __PTHREAD_SPINS { 0, 0 }
+#else
+#define __PTHREAD_SPINS 0
+#endif
+
#ifdef __PTHREAD_MUTEX_HAVE_PREV
# define PTHREAD_MUTEX_INITIALIZER \
- { { 0, 0, 0, 0, 0, 0, { 0, 0 } } }
+ { { 0, 0, 0, 0, 0, __PTHREAD_SPINS, { 0, 0 } } }
# ifdef __USE_GNU
# define PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP \
- { { 0, 0, 0, 0, PTHREAD_MUTEX_RECURSIVE_NP, 0, { 0, 0 } } }
+ { { 0, 0, 0, 0, PTHREAD_MUTEX_RECURSIVE_NP, __PTHREAD_SPINS, { 0, 0 } } }
# define PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP \
- { { 0, 0, 0, 0, PTHREAD_MUTEX_ERRORCHECK_NP, 0, { 0, 0 } } }
+ { { 0, 0, 0, 0, PTHREAD_MUTEX_ERRORCHECK_NP, __PTHREAD_SPINS, { 0, 0 } } }
# define PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP \
- { { 0, 0, 0, 0, PTHREAD_MUTEX_ADAPTIVE_NP, 0, { 0, 0 } } }
+ { { 0, 0, 0, 0, PTHREAD_MUTEX_ADAPTIVE_NP, __PTHREAD_SPINS, { 0, 0 } } }
+# define PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP \
+ { { 0, 0, 0, 0, PTHREAD_MUTEX_ADAPTIVE_NP, __PTHREAD_SPINS, { 0, 0 } } }
+
# endif
#else
# define PTHREAD_MUTEX_INITIALIZER \
- { { 0, 0, 0, 0, 0, { 0 } } }
+ { { 0, 0, 0, 0, 0, { __PTHREAD_SPINS } } }
# ifdef __USE_GNU
# define PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP \
- { { 0, 0, 0, PTHREAD_MUTEX_RECURSIVE_NP, 0, { 0 } } }
+ { { 0, 0, 0, PTHREAD_MUTEX_RECURSIVE_NP, 0, { __PTHREAD_SPINS } } }
# define PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP \
- { { 0, 0, 0, PTHREAD_MUTEX_ERRORCHECK_NP, 0, { 0 } } }
+ { { 0, 0, 0, PTHREAD_MUTEX_ERRORCHECK_NP, 0, { __PTHREAD_SPINS } } }
# define PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP \
- { { 0, 0, 0, PTHREAD_MUTEX_ADAPTIVE_NP, 0, { 0 } } }
+ { { 0, 0, 0, PTHREAD_MUTEX_ADAPTIVE_NP, 0, { __PTHREAD_SPINS } } }
+
# endif
#endif
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=1cdbe579482c07e9f4bb3baa4864da2d3e7eb837
commit 1cdbe579482c07e9f4bb3baa4864da2d3e7eb837
Author: Andi Kleen <ak@linux.intel.com>
Date: Sat Nov 10 00:51:26 2012 -0800
Add the low level infrastructure for pthreads lock elision with TSX
Lock elision using TSX is a technique to optimize lock scaling
It allows to run locks in parallel using hardware support for
a transactional execution mode in 4th generation Intel Core CPUs.
See http://www.intel.com/software/tsx for more Information.
This patch implements a simple adaptive lock elision algorithm based
on RTM. It enables elision for the pthread mutexes and rwlocks.
The algorithm keeps track whether a mutex successfully elides or not,
and stops eliding for some time when it is not.
When the CPU supports RTM the elision path is automatically tried,
otherwise any elision is disabled.
The adaptation algorithm and its tuning is currently preliminary.
The code adds some checks to the lock fast paths. Micro-benchmarks
show little to no difference without RTM.
This patch implements the low level "lll_" code for lock elision.
Followon patches hook this into the pthread implementation
Changes with the RTM mutexes:
-----------------------------
Lock elision in pthreads is generally compatible with existing programs.
There are some obscure exceptions, which are expected to be uncommon.
See the manual for more details.
- A broken program that unlocks a free lock will crash.
There are ways around this with some tradeoffs (more code in hot paths)
I'm still undecided on what approach to take here; have to wait for testing reports.
- pthread_mutex_destroy of a lock mutex will not return EBUSY but 0.
- There's also a similar situation with trylock outside the mutex,
"knowing" that the mutex must be held due to some other condition.
In this case an assert failure cannot be recovered. This situation is
usually an existing bug in the program.
- Same applies to the rwlocks. Some of the return values changes
(for example there is no EDEADLK for an elided lock, unless it aborts.
However when elided it will also never deadlock of course)
- Timing changes, so broken programs that make assumptions about specific timing
may expose already existing latent problems. Note that these broken programs will
break in other situations too (loaded system, new faster hardware, compiler
optimizations etc.)
- Programs with non recursive mutexes that take them recursively in a thread and
which would always deadlock without elision may not always see a deadlock.
The deadlock will only happen on an early or delayed abort (which typically
happens at some point)
This only happens for mutexes not explicitely set to PTHREAD_MUTEX_NORMAL
or PTHREAD_MUTEX_ADAPTIVE_NP. PTHREAD_MUTEX_NORMAL mutexes do not elide.
The elision default can be set at configure time.
This patch implements the basic infrastructure for elision.
diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index 7c03548..d5eb9ea 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,3 +1,24 @@
+2013-07-02 Andi Kleen <ak@linux.intel.com>
+ Hongjiu Lu <hongjiu.lu@intel.com>
+
+ * sysdeps/unix/sysv/linux/i386/lowlevellock.h (__lll_timedwait_tid,
+ lll_timedlock_elision, __lll_lock_elision, __lll_unlock_elision,
+ __lll_trylock_elision, lll_lock_elision, lll_unlock_elision,
+ lll_trylock_elision): Add.
+ * sysdeps/unix/sysv/linux/x86/Makefile: Imply x86.
+ * sysdeps/unix/sysv/linux/x86/elision-conf.c: New file.
+ * sysdeps/unix/sysv/linux/x86/elision-conf.h: New file.
+ * sysdeps/unix/sysv/linux/x86/elision-lock.c: New file.
+ * sysdeps/unix/sysv/linux/x86/elision-timed.c: New file.
+ * sysdeps/unix/sysv/linux/x86/elision-trylock.c: New file.
+ * sysdeps/unix/sysv/linux/x86/elision-unlock.c: New file.
+ * sysdeps/unix/sysv/linux/x86_64/lowlevellock.h (__lll_timedwait_tid,
+ lll_timedlock_elision, __lll_lock_elision, __lll_unlock_elision,
+ __lll_trylock_elision, lll_lock_elision, lll_unlock_elision,
+ lll_trylock_elision): Add.
+ * nptl/sysdeps/unix/sysv/linux/x86/hle.h: New file.
+ * elision-conf.h: New file.
+
2013-06-24 Vladimir Nikulichev <v.nikulichev@gmail.com>
[BZ #12310]
diff --git a/nptl/elision-conf.h b/nptl/elision-conf.h
new file mode 100644
index 0000000..40a8c17
--- /dev/null
+++ b/nptl/elision-conf.h
@@ -0,0 +1 @@
+/* empty */
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h
index f665ac9..cc3ec5b 100644
--- a/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h
+++ b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h
@@ -430,6 +430,12 @@ LLL_STUB_UNWIND_INFO_END
: "memory"); \
result; })
+extern int __lll_timedlock_elision (int *futex, short *adapt_count,
+ const struct timespec *timeout,
+ int private) attribute_hidden;
+
+#define lll_timedlock_elision(futex, adapt_count, timeout, private) \
+ __lll_timedlock_elision(&(futex), &(adapt_count), timeout, private)
#define lll_robust_timedlock(futex, timeout, id, private) \
({ int result, ignore1, ignore2, ignore3; \
@@ -583,6 +589,22 @@ extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
} \
__result; })
+extern int __lll_lock_elision (int *futex, short *adapt_count, int private)
+ attribute_hidden;
+
+extern int __lll_unlock_elision(int *lock, int private)
+ attribute_hidden;
+
+extern int __lll_trylock_elision(int *lock, short *adapt_count)
+ attribute_hidden;
+
+#define lll_lock_elision(futex, adapt_count, private) \
+ __lll_lock_elision (&(futex), &(adapt_count), private)
+#define lll_unlock_elision(futex, private) \
+ __lll_unlock_elision (&(futex), private)
+#define lll_trylock_elision(futex, adapt_count) \
+ __lll_trylock_elision(&(futex), &(adapt_count))
+
#endif /* !__ASSEMBLER__ */
#endif /* lowlevellock.h */
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/Makefile b/nptl/sysdeps/unix/sysv/linux/x86/Makefile
new file mode 100644
index 0000000..61b7552
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/Makefile
@@ -0,0 +1,3 @@
+libpthread-sysdep_routines += init-arch
+libpthread-sysdep_routines += elision-lock elision-unlock elision-timed \
+ elision-trylock
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.c b/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.c
new file mode 100644
index 0000000..6277e48
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.c
@@ -0,0 +1,87 @@
+/* elision-conf.c: Lock elision tunable parameters.
+ Copyright (C) 2013 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/>. */
+
+#include <pthreadP.h>
+#include <init-arch.h>
+#include <elision-conf.h>
+#include <unistd.h>
+
+/* Reasonable initial tuning values, may be revised in the future.
+ This is a conservative initial value. */
+
+struct elision_config __elision_aconf =
+ {
+ /* How often to not attempt to use elision if a transaction aborted
+ because the lock is already acquired. Expressed in number of lock
+ acquisition attempts. */
+ .skip_lock_busy = 3,
+ /* How often to not attempt to use elision if a transaction aborted due
+ to reasons other than other threads' memory accesses. Expressed in
+ number of lock acquisition attempts. */
+ .skip_lock_internal_abort = 3,
+ /* How often we retry using elision if there is chance for the transaction
+ to finish execution (e.g., it wasn't aborted due to the lock being
+ already acquired. */
+ .retry_try_xbegin = 3,
+ /* Same as SKIP_LOCK_INTERNAL_ABORT but for trylock. */
+ .skip_trylock_internal_abort = 3,
+ };
+
+/* Elided rwlock toggle, set when elision is available and is
+ enabled for rwlocks. */
+
+int __rwlock_rtm_enabled attribute_hidden;
+
+/* Retries for elided rwlocks on read. Conservative initial value. */
+
+int __rwlock_rtm_read_retries attribute_hidden = 3;
+
+/* Set when the CPU supports elision. When false elision is never attempted. */
+
+int __elision_available attribute_hidden;
+
+/* Force elision for all new locks. This is used to decide whether existing
+ DEFAULT locks should be automatically upgraded to elision in
+ pthread_mutex_lock(). Disabled for suid programs. Only used when elision
+ is available. */
+
+int __pthread_force_elision attribute_hidden;
+
+/* Initialize elison. */
+
+static void
+elision_init (int argc __attribute__ ((unused)),
+ char **argv __attribute__ ((unused)),
+ char **environ)
+{
+ __elision_available = HAS_RTM;
+ __pthread_force_elision = __libc_enable_secure ? 0 : __elision_available;
+ __rwlock_rtm_enabled = __libc_enable_secure ? 0 : __elision_available;
+}
+
+#ifdef SHARED
+# define INIT_SECTION ".init_array"
+#else
+# define INIT_SECTION ".preinit_array"
+#endif
+
+void (*const __pthread_init_array []) (int, char **, char **)
+ __attribute__ ((section (INIT_SECTION), aligned (sizeof (void *)))) =
+{
+ &elision_init
+};
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.h b/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.h
new file mode 100644
index 0000000..55b81db
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/elision-conf.h
@@ -0,0 +1,44 @@
+/* elision-conf.h: Lock elision tunable parameters.
+ Copyright (C) 2013 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 _ELISION_CONF_H
+#define _ELISION_CONF_H 1
+
+#include <pthread.h>
+#include <cpuid.h>
+#include <time.h>
+
+/* Should make sure there is no false sharing on this. */
+
+struct elision_config
+{
+ int skip_lock_busy;
+ int skip_lock_internal_abort;
+ int retry_try_xbegin;
+ int skip_trylock_internal_abort;
+};
+
+extern struct elision_config __elision_aconf attribute_hidden;
+
+extern int __rwlock_rtm_enabled attribute_hidden;
+extern int __elision_available attribute_hidden;
+extern int __pthread_force_elision attribute_hidden;
+
+/* Tell the test suite to test elision for this architecture. */
+#define HAVE_ELISION 1
+
+#endif
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/elision-lock.c b/nptl/sysdeps/unix/sysv/linux/x86/elision-lock.c
new file mode 100644
index 0000000..de16f1b
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/elision-lock.c
@@ -0,0 +1,95 @@
+/* elision-lock.c: Elided pthread mutex lock.
+ Copyright (C) 2011-2013 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/>. */
+
+#include <pthread.h>
+#include "pthreadP.h"
+#include "lowlevellock.h"
+#include "hle.h"
+#include <elision-conf.h>
+
+#if !defined(LLL_LOCK) && !defined(EXTRAARG)
+/* Make sure the configuration code is always linked in for static
+ libraries. */
+#include "elision-conf.c"
+#endif
+
+#ifndef EXTRAARG
+#define EXTRAARG
+#endif
+#ifndef LLL_LOCK
+#define LLL_LOCK(a,b) lll_lock(a,b), 0
+#endif
+
+#define aconf __elision_aconf
+
+/* Adaptive lock using transactions.
+ By default the lock region is run as a transaction, and when it
+ aborts or the lock is busy the lock adapts itself. */
+
+int
+__lll_lock_elision (int *futex, short *adapt_count, EXTRAARG int private)
+{
+ if (*adapt_count <= 0)
+ {
+ unsigned status;
+ int try_xbegin;
+
+ for (try_xbegin = aconf.retry_try_xbegin;
+ try_xbegin > 0;
+ try_xbegin--)
+ {
+ if ((status = _xbegin()) == _XBEGIN_STARTED)
+ {
+ if (*futex == 0)
+ return 0;
+
+ /* Lock was busy. Fall back to normal locking.
+ Could also _xend here but xabort with 0xff code
+ is more visible in the profiler. */
+ _xabort (_ABORT_LOCK_BUSY);
+ }
+
+ if (!(status & _XABORT_RETRY))
+ {
+ if ((status & _XABORT_EXPLICIT)
+ && _XABORT_CODE (status) == _ABORT_LOCK_BUSY)
+ {
+ /* Right now we skip here. Better would be to wait a bit
+ and retry. This likely needs some spinning. */
+ if (*adapt_count != aconf.skip_lock_busy)
+ *adapt_count = aconf.skip_lock_busy;
+ }
+ /* Internal abort. There is no chance for retry.
+ Use the normal locking and next time use lock.
+ Be careful to avoid writing to the lock. */
+ else if (*adapt_count != aconf.skip_lock_internal_abort)
+ *adapt_count = aconf.skip_lock_internal_abort;
+ break;
+ }
+ }
+ }
+ else
+ {
+ /* Use a normal lock until the threshold counter runs out.
+ Lost updates possible. */
+ (*adapt_count)--;
+ }
+
+ /* Use a normal lock here. */
+ return LLL_LOCK ((*futex), private);
+}
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/elision-timed.c b/nptl/sysdeps/unix/sysv/linux/x86/elision-timed.c
new file mode 100644
index 0000000..8825d12
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/elision-timed.c
@@ -0,0 +1,26 @@
+/* elision-timed.c: Lock elision timed lock.
+ Copyright (C) 2013 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/>. */
+
+#include <time.h>
+#include <elision-conf.h>
+#include "lowlevellock.h"
+#define __lll_lock_elision __lll_timedlock_elision
+#define EXTRAARG const struct timespec *t,
+#undef LLL_LOCK
+#define LLL_LOCK(a, b) lll_timedlock(a, t, b)
+#include "elision-lock.c"
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c b/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c
new file mode 100644
index 0000000..2939fc9
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c
@@ -0,0 +1,72 @@
+/* elision-trylock.c: Lock eliding trylock for pthreads.
+ Copyright (C) 2013 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/>. */
+
+#include <pthread.h>
+#include <pthreadP.h>
+#include <lowlevellock.h>
+#include "hle.h"
+#include <elision-conf.h>
+
+#define aconf __elision_aconf
+
+/* Try to elide a futex trylock. FUTEX is the futex variable. TRY_LOCK is the
+ adaptation counter in the mutex. UPGRADED is != 0 when this is for an
+ automatically upgraded lock. */
+
+int
+__lll_trylock_elision (int *futex, short *adapt_count)
+{
+ /* Implement POSIX semantics by forbiding nesting
+ trylock. Sorry. After the abort the code is re-executed
+ non transactional and if the lock was already locked
+ return an error. */
+ _xabort (_ABORT_NESTED_TRYLOCK);
+
+ /* Only try a transaction if it's worth it. */
+ if (*adapt_count <= 0)
+ {
+ unsigned status;
+
+ if ((status = _xbegin()) == _XBEGIN_STARTED)
+ {
+ if (*futex == 0)
+ return 0;
+
+ /* Lock was busy. Fall back to normal locking.
+ Could also _xend here but xabort with 0xff code
+ is more visible in the profiler. */
+ _xabort (_ABORT_LOCK_BUSY);
+ }
+
+ if (!(status & _XABORT_RETRY))
+ {
+ /* Internal abort. No chance for retry. For future
+ locks don't try speculation for some time. */
+ if (*adapt_count != aconf.skip_trylock_internal_abort)
+ *adapt_count = aconf.skip_trylock_internal_abort;
+ }
+ /* Could do some retries here. */
+ }
+ else
+ {
+ /* Lost updates are possible, but harmless. */
+ (*adapt_count)--;
+ }
+
+ return lll_trylock (*futex);
+}
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/elision-unlock.c b/nptl/sysdeps/unix/sysv/linux/x86/elision-unlock.c
new file mode 100644
index 0000000..bb13c6b
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/elision-unlock.c
@@ -0,0 +1,33 @@
+/* elision-unlock.c: Commit an elided pthread lock.
+ Copyright (C) 2013 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/>. */
+
+#include "pthreadP.h"
+#include "lowlevellock.h"
+#include "hle.h"
+
+int
+__lll_unlock_elision(int *lock, int private)
+{
+ /* When the lock was free we're in a transaction.
+ When you crash here you unlocked a free lock. */
+ if (*lock == 0)
+ _xend();
+ else
+ lll_unlock ((*lock), private);
+ return 0;
+}
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/hle.h b/nptl/sysdeps/unix/sysv/linux/x86/hle.h
new file mode 100644
index 0000000..a08f0fa
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86/hle.h
@@ -0,0 +1,75 @@
+/* Shared RTM header. Emulate TSX intrinsics for compilers and assemblers
+ that do not support the intrinsics and instructions yet. */
+#ifndef _HLE_H
+#define _HLE_H 1
+
+#ifdef __ASSEMBLER__
+
+.macro XBEGIN target
+ .byte 0xc7,0xf8
+ .long \target-1f
+1:
+.endm
+
+.macro XEND
+ .byte 0x0f,0x01,0xd5
+.endm
+
+.macro XABORT code
+ .byte 0xc6,0xf8,\code
+.endm
+
+.macro XTEST
+ .byte 0x0f,0x01,0xd6
+.endm
+
+#endif
+
+/* Official RTM intrinsics interface matching gcc/icc, but works
+ on older gcc compatible compilers and binutils.
+ We should somehow detect if the compiler supports it, because
+ it may be able to generate slightly better code. */
+
+#define _XBEGIN_STARTED (~0u)
+#define _XABORT_EXPLICIT (1 << 0)
+#define _XABORT_RETRY (1 << 1)
+#define _XABORT_CONFLICT (1 << 2)
+#define _XABORT_CAPACITY (1 << 3)
+#define _XABORT_DEBUG (1 << 4)
+#define _XABORT_NESTED (1 << 5)
+#define _XABORT_CODE(x) (((x) >> 24) & 0xff)
+
+#define _ABORT_LOCK_BUSY 0xff
+#define _ABORT_LOCK_IS_LOCKED 0xfe
+#define _ABORT_NESTED_TRYLOCK 0xfd
+
+#ifndef __ASSEMBLER__
+
+#define __force_inline __attribute__((__always_inline__)) inline
+
+static __force_inline int _xbegin(void)
+{
+ int ret = _XBEGIN_STARTED;
+ asm volatile (".byte 0xc7,0xf8 ; .long 0" : "+a" (ret) :: "memory");
+ return ret;
+}
+
+static __force_inline void _xend(void)
+{
+ asm volatile (".byte 0x0f,0x01,0xd5" ::: "memory");
+}
+
+static __force_inline void _xabort(const unsigned int status)
+{
+ asm volatile (".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory");
+}
+
+static __force_inline int _xtest(void)
+{
+ unsigned char out;
+ asm volatile (".byte 0x0f,0x01,0xd6 ; setnz %0" : "=r" (out) :: "memory");
+ return out;
+}
+
+#endif
+#endif
diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h
index 7a176ae..35fb01a 100644
--- a/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h
+++ b/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h
@@ -427,6 +427,13 @@ LLL_STUB_UNWIND_INFO_END
: "memory", "cx", "cc", "r10", "r11"); \
result; })
+extern int __lll_timedlock_elision (int *futex, short *adapt_count,
+ const struct timespec *timeout,
+ int private) attribute_hidden;
+
+#define lll_timedlock_elision(futex, adapt_count, timeout, private) \
+ __lll_timedlock_elision(&(futex), &(adapt_count), timeout, private)
+
#define lll_robust_timedlock(futex, timeout, id, private) \
({ int result, ignore1, ignore2, ignore3; \
__asm __volatile (LOCK_INSTR "cmpxchgl %1, %4\n\t" \
@@ -597,6 +604,22 @@ extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
} \
__result; })
+extern int __lll_lock_elision (int *futex, short *adapt_count, int private)
+ attribute_hidden;
+
+extern int __lll_unlock_elision (int *lock, int private)
+ attribute_hidden;
+
+extern int __lll_trylock_elision (int *lock, short *adapt_count)
+ attribute_hidden;
+
+#define lll_lock_elision(futex, adapt_count, private) \
+ __lll_lock_elision (&(futex), &(adapt_count), private)
+#define lll_unlock_elision(futex, private) \
+ __lll_unlock_elision (&(futex), private)
+#define lll_trylock_elision(futex, adapt_count) \
+ __lll_trylock_elision (&(futex), &(adapt_count))
+
#endif /* !__ASSEMBLER__ */
#endif /* lowlevellock.h */
-----------------------------------------------------------------------
Summary of changes:
ChangeLog | 8 ++
INSTALL | 3 +
config.h.in | 3 +
configure | 16 ++++
configure.in | 9 ++
manual/install.texi | 3 +
nptl/ChangeLog | 66 ++++++++++++++
nptl/elision-conf.h | 1 +
nptl/pthreadP.h | 17 ++++-
nptl/pthread_mutex_lock.c | 53 +++++++++--
nptl/pthread_mutex_timedlock.c | 24 +++++-
nptl/pthread_mutex_trylock.c | 32 ++++++-
nptl/pthread_mutex_unlock.c | 21 ++++-
nptl/pthread_mutexattr_settype.c | 5 +
nptl/sysdeps/pthread/pthread.h | 28 ++++--
nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h | 22 +++++
.../unix/sysv/linux/pthread_mutex_cond_lock.c | 7 ++
nptl/sysdeps/unix/sysv/linux/x86/Makefile | 3 +
.../unix/sysv/linux/x86/bits/pthreadtypes.h | 13 +++-
nptl/sysdeps/unix/sysv/linux/x86/elision-conf.c | 90 ++++++++++++++++++
nptl/sysdeps/unix/sysv/linux/x86/elision-conf.h | 44 +++++++++
nptl/sysdeps/unix/sysv/linux/x86/elision-lock.c | 95 ++++++++++++++++++++
nptl/sysdeps/unix/sysv/linux/x86/elision-timed.c | 26 ++++++
nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c | 71 +++++++++++++++
nptl/sysdeps/unix/sysv/linux/x86/elision-unlock.c | 33 +++++++
nptl/sysdeps/unix/sysv/linux/x86/force-elision.h | 31 +++++++
nptl/sysdeps/unix/sysv/linux/x86/hle.h | 75 +++++++++++++++
.../unix/sysv/linux/x86/pthread_mutex_cond_lock.c | 21 +++++
.../unix/sysv/linux/x86/pthread_mutex_lock.c | 21 +++++
.../unix/sysv/linux/x86/pthread_mutex_timedlock.c | 20 ++++
.../unix/sysv/linux/x86/pthread_mutex_trylock.c | 21 +++++
nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h | 23 +++++
nptl/tst-mutex5.c | 4 +
nptl/tst-mutex8.c | 17 ++++-
34 files changed, 896 insertions(+), 30 deletions(-)
create mode 100644 nptl/elision-conf.h
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/Makefile
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/elision-conf.c
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/elision-conf.h
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/elision-lock.c
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/elision-timed.c
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/elision-unlock.c
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/force-elision.h
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/hle.h
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_cond_lock.c
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_lock.c
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_timedlock.c
create mode 100644 nptl/sysdeps/unix/sysv/linux/x86/pthread_mutex_trylock.c
hooks/post-receive
--
GNU C Library master sources