From patchwork Thu Apr 24 14:42:21 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Liebler X-Patchwork-Id: 668 Return-Path: X-Original-To: siddhesh@wilcox.dreamhost.com Delivered-To: siddhesh@wilcox.dreamhost.com Received: from homiemail-mx22.g.dreamhost.com (mx2.sub5.homie.mail.dreamhost.com [208.113.200.128]) by wilcox.dreamhost.com (Postfix) with ESMTP id D3487360D42 for ; Thu, 24 Apr 2014 07:42:44 -0700 (PDT) Received: by homiemail-mx22.g.dreamhost.com (Postfix, from userid 14307373) id 90F714F43800; Thu, 24 Apr 2014 07:42:44 -0700 (PDT) X-Original-To: glibc@patchwork.siddhesh.in Delivered-To: x14307373@homiemail-mx22.g.dreamhost.com Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by homiemail-mx22.g.dreamhost.com (Postfix) with ESMTPS id 6C3D34F3F7A8 for ; Thu, 24 Apr 2014 07:42:44 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:to:from:subject:date:message-id:mime-version :content-type; q=dns; s=default; b=YmvpedGVDGYYHo2rHIMtLoUZiTcb4 kIk0qrteNNaqIQRI4fyXebCtCn86W2qyziRjF0+h1BIjKXI33OU2dJsyVYVgFcdR 46MoW4k8PNbD6X+7iO/c3J9sP319jSxDdFY0D0eORwNamgwzCBT5gJoq88uBfmBh UKnbocAjabCb/c= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:to:from:subject:date:message-id:mime-version :content-type; s=default; bh=WhE6XwaiTXt2hkLy+h9P9YZTXQo=; b=MlL TgOvD+kRfeE2q4zj1pm61s2RqTye9P9nEQ92j1Tlo7hyAUtNREJZuMQhKU+94D27 P4xKcpiD9w4fddWwIHdTWglXk/M7IWRNK5ID6/TgDbejP6ASNigJuQgfUEgKU9OX McStDTz5W5OMe/SdyKCVKCc8vn+RZgougBQjHtVw= Received: (qmail 14886 invoked by alias); 24 Apr 2014 14:42:42 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 14877 invoked by uid 89); 24 Apr 2014 14:42:41 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.4 required=5.0 tests=AWL, BAYES_00, RCVD_IN_DNSWL_NONE, RP_MATCHES_RCVD, SPF_HELO_PASS, SPF_PASS autolearn=ham version=3.3.2 X-HELO: plane.gmane.org To: libc-alpha@sourceware.org From: Stefan Liebler Subject: [PATCH] S/390: Port of lock elision to System/z Date: Thu, 24 Apr 2014 16:42:21 +0200 Lines: 931 Message-ID: Mime-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 X-DH-Original-To: glibc@patchwork.siddhesh.in Hi, this is a port of the lock elision implementation of Intel to System/z. This is the continuation of Dominik Vogts patch (https://sourceware.org/ml/libc-alpha/2013-11/msg00546.html). The lock elision code is only built with --enable-lock-elision=yes. Then default mutexes are elided via __builtin_tbegin, if the cpu supports transactions. By default lock elision is not enabled and the elision code is not built (Intel always builds the elision code). This is necessary in order to compile glibc on S/390 with an gcc without transactions-support. The requirements on gcc are checked by configure-script. Binutils are needed in version 2.24, which is already checked by configure-script. The patch is tested on S390 / S390x with lock-elision enabled /disabled. This implementation breaks pthread_mutex_destroy in the same way as described in Bug 16657. Ok? Bye --- 2014-04-24 Stefan Liebler * config.make.in (enable-lock-elision): New Makefile variable. * configure.ac: Likewise. * configure: Regenerate. * sysdeps/s390/configure.ac: Add check for gcc transactions support. * sysdeps/s390/configure: Regenerate. * nptl/sysdeps/unix/sysv/linux/s390/Makefile: New file. Build elision files if enabled. * nptl/sysdeps/unix/sysv/linux/s390/elision-conf.c: New file. Add lock elision support for s390. * nptl/sysdeps/unix/sysv/linux/s390/elision-conf.h: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/elision-lock.c: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/elision-timed.c: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/elision-trylock.c: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/elision-unlock.c: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/force-elision.h: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_cond_lock.c: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_lock.c: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_timedlock.c: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_trylock.c: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_unlock.c: Likewise. * nptl/sysdeps/unix/sysv/linux/s390/lowlevellock.h: (__lll_timedlock_elision, __lll_lock_elision) (__lll_unlock_elision, __lll_trylock_elision) (lll_timedlock_elision, lll_lock_elision) (lll_unlock_elision, lll_trylock_elision): Add. * nptl/sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h (pthread_mutex_t): Add lock elision support for s390. --- diff --git a/config.make.in b/config.make.in index 132d179..6bcab8a 100644 --- a/config.make.in +++ b/config.make.in @@ -93,6 +93,7 @@ build-nscd = @build_nscd@ use-nscd = @use_nscd@ build-hardcoded-path-in-tests= @hardcoded_path_in_tests@ build-pt-chown = @build_pt_chown@ +enable-lock-elision = @enable_lock_elision@ # Build tools. CC = @CC@ diff --git a/configure b/configure index 8b0b222..ecc282b 100755 --- a/configure +++ b/configure @@ -651,6 +651,7 @@ libc_cv_nss_crypt all_warnings force_install bindnow +enable_lock_elision hardcoded_path_in_tests oldest_abi use_default_link @@ -3476,6 +3477,7 @@ else enable_lock_elision=no fi + if test "$enable_lock_elision" = yes ; then $as_echo "#define ENABLE_LOCK_ELISION 1" >>confdefs.h diff --git a/configure.ac b/configure.ac index 97a9591..babfe57 100644 --- a/configure.ac +++ b/configure.ac @@ -184,6 +184,7 @@ AC_ARG_ENABLE([lock-elision], [Enable lock elision for pthread mutexes by default]), [enable_lock_elision=$enableval], [enable_lock_elision=no]) +AC_SUBST(enable_lock_elision) if test "$enable_lock_elision" = yes ; then AC_DEFINE(ENABLE_LOCK_ELISION) fi diff --git a/nptl/sysdeps/unix/sysv/linux/s390/Makefile b/nptl/sysdeps/unix/sysv/linux/s390/Makefile new file mode 100644 index 0000000..269832f --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/Makefile @@ -0,0 +1,10 @@ +ifeq ($(enable-lock-elision),yes) +libpthread-sysdep_routines += elision-lock elision-unlock elision-timed \ + elision-trylock + +elision-CFLAGS = -mhtm +CFLAGS-elision-lock.c = $(elision-CFLAGS) +CFLAGS-elision-timed.c = $(elision-CFLAGS) +CFLAGS-elision-trylock.c = $(elision-CFLAGS) +CFLAGS-elision-unlock.c = $(elision-CFLAGS) +endif diff --git a/nptl/sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h b/nptl/sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h index 8264de0..d70f8b3 100644 --- a/nptl/sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h +++ b/nptl/sysdeps/unix/sysv/linux/s390/bits/pthreadtypes.h @@ -89,14 +89,37 @@ typedef union binary compatibility. */ int __kind; #if __WORDSIZE == 64 +# ifdef ENABLE_LOCK_ELISION + short __spins; + short __elision; + /* Mutex __spins initializer used by PTHREAD_MUTEX_INITIALIZER. */ +# define __PTHREAD_SPINS 0, 0 +# else int __spins; + /* Mutex __spins initializer used by PTHREAD_MUTEX_INITIALIZER. */ +# define __PTHREAD_SPINS 0 +# endif __pthread_list_t __list; # define __PTHREAD_MUTEX_HAVE_PREV 1 #else unsigned int __nusers; __extension__ union { +# ifdef ENABLE_LOCK_ELISION + struct + { + short __espins; + short __elision; + } _d; +# define __spins _d.__espins +# define __elision _d.__elision + /* Mutex __spins initializer used by PTHREAD_MUTEX_INITIALIZER. */ +# define __PTHREAD_SPINS { 0, 0 } +# else int __spins; + /* Mutex __spins initializer used by PTHREAD_MUTEX_INITIALIZER. */ +# define __PTHREAD_SPINS 0 +# endif __pthread_slist_t __list; }; #endif @@ -105,8 +128,6 @@ typedef union long int __align; } pthread_mutex_t; -/* Mutex __spins initializer used by PTHREAD_MUTEX_INITIALIZER. */ -#define __PTHREAD_SPINS 0 typedef union { diff --git a/nptl/sysdeps/unix/sysv/linux/s390/elision-conf.c b/nptl/sysdeps/unix/sysv/linux/s390/elision-conf.c new file mode 100644 index 0000000..b92e0ea --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/elision-conf.c @@ -0,0 +1,81 @@ +/* Lock elision tunable parameters. + 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 + . */ + +#include +#include +#include +#include +#include + +/* 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 to not attempt to use elision if a lock used up all retries + without success. Expressed in number of lock acquisition attempts. */ + .skip_lock_out_of_tbegin_retries = 3, + /* How often we try 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. */ + .try_tbegin = 3, + /* Same as SKIP_LOCK_INTERNAL_ABORT but for trylock. */ + .skip_trylock_internal_abort = 3, + }; + +/* 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 = 0; + +/* Initialize elison. */ + +static void +elision_init (int argc __attribute__ ((unused)), + char **argv __attribute__ ((unused)), + char **environ) +{ + /* Set when the CPU supports elision. When false elision is never attempted. */ + int elision_available = (GLRO (dl_hwcap) & HWCAP_S390_TE) ? 1 : 0; + + __pthread_force_elision = __libc_enable_secure ? 0 : elision_available; +} + +#ifdef SHARED +# define INIT_SECTION ".init_array" +# define MAYBE_CONST +#else +# define INIT_SECTION ".preinit_array" +# define MAYBE_CONST const +#endif + +void (*MAYBE_CONST __pthread_init_array []) (int, char **, char **) + __attribute__ ((section (INIT_SECTION), aligned (sizeof (void *)))) = +{ + &elision_init +}; diff --git a/nptl/sysdeps/unix/sysv/linux/s390/elision-conf.h b/nptl/sysdeps/unix/sysv/linux/s390/elision-conf.h new file mode 100644 index 0000000..d9e9794 --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/elision-conf.h @@ -0,0 +1,44 @@ +/* Lock elision tunable parameters. + 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 + . */ +#ifdef ENABLE_LOCK_ELISION +#ifndef _ELISION_CONF_H +#define _ELISION_CONF_H 1 + +#include +#include + +/* Should make sure there is no false sharing on this. */ + +struct elision_config +{ + int skip_lock_busy; + int skip_lock_internal_abort; + int skip_lock_out_of_tbegin_retries; + int try_tbegin; + int skip_trylock_internal_abort; +}; + +extern struct elision_config __elision_aconf attribute_hidden; + +extern int __pthread_force_elision attribute_hidden; + +/* Tell the test suite to test elision for this architecture. */ +#define HAVE_ELISION 1 + +#endif +#endif diff --git a/nptl/sysdeps/unix/sysv/linux/s390/elision-lock.c b/nptl/sysdeps/unix/sysv/linux/s390/elision-lock.c new file mode 100644 index 0000000..89b647c --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/elision-lock.c @@ -0,0 +1,123 @@ +/* Elided pthread mutex lock. + 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 + . */ + +#include +#include +#include +#include +#include +#include + +#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) + { + __asm__ volatile (".machinemode \"zarch_nohighgprs\"\n\t" + ".machine \"all\"" + : : : "memory"); + + int try_tbegin; + for (try_tbegin = aconf.try_tbegin; + try_tbegin > 0; + try_tbegin--) + { + unsigned status; + if (__builtin_expect + ((status = __builtin_tbegin((void *)0)) == _HTM_TBEGIN_STARTED, 1)) + { + if (*futex == 0) + return 0; + /* Lock was busy. Fall back to normal locking. */ + if (__builtin_expect (__builtin_tx_nesting_depth (), 1)) + { + /* In a non-nested transaction there is no need to abort, + which is expensive. */ + __builtin_tend (); + if (aconf.skip_lock_busy > 0) + *adapt_count = aconf.skip_lock_busy; + goto use_lock; + } + else /* nesting depth is > 1 */ + { + /* A nested transaction will abort eventually because it + cannot make any progress before *futex changes back to 0. + So we may as well abort immediately. + This persistently aborts the outer transaction to force + the outer mutex use the default lock instead of retrying + with transactions until the try_tbegin of the outer mutex + is zero. + The adapt_count of this inner mutex is not changed, + because using the default lock with the inner mutex + would abort the outer transaction. + */ + __builtin_tabort (_HTM_FIRST_USER_ABORT_CODE + 1); + } + } + else + { + asm volatile ("" ::: "f0", "f1", "f2", "f3", "f4", "f5", "f6", + "f7", "f8", "f9", "f10", "f11", "f12", "f13", + "f14", "f15", "cc", "memory"); + + if (status != _HTM_TBEGIN_TRANSIENT) + { + /* A persistent abort (cc 1 or 3) indicates that a retry is + probably futile. Use the normal locking now and for the + next couple of calls. + Be careful to avoid writing to the lock. */ + 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 tepmorary failures in a + row. */ + if (aconf.skip_lock_out_of_tbegin_retries > 0 && aconf.try_tbegin > 0) + *adapt_count = aconf.skip_lock_out_of_tbegin_retries; + } + else + { + /* Lost updates are possible, but harmless. Due to races this might lead + to *adapt_count becoming less than zero. */ + (*adapt_count)--; + } + + use_lock: + return LLL_LOCK ((*futex), private); +} diff --git a/nptl/sysdeps/unix/sysv/linux/s390/elision-timed.c b/nptl/sysdeps/unix/sysv/linux/s390/elision-timed.c new file mode 100644 index 0000000..a8d8b2a --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/elision-timed.c @@ -0,0 +1,26 @@ +/* Lock elision timed lock. + 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 + . */ + +#include +#include +#include +#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/s390/elision-trylock.c b/nptl/sysdeps/unix/sysv/linux/s390/elision-trylock.c new file mode 100644 index 0000000..8ec8c71 --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/elision-trylock.c @@ -0,0 +1,97 @@ +/* Elided pthread mutex trylock. + 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 + . */ + +#include +#include +#include +#include +#include + +#define aconf __elision_aconf + +/* 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) +{ + __asm__ volatile (".machinemode \"zarch_nohighgprs\"\n\t" + ".machine \"all\"" + : : : "memory"); + + /* Implement POSIX semantics by forbiding nesting elided trylocks. + Sorry. After the abort the code is re-executed + non transactional and if the lock was already locked + return an error. */ + if (__builtin_tx_nesting_depth () > 0) + { + /* Note that this abort may terminate an outermost transaction that + was created outside glibc. + This persistently aborts the current transactions to force + them to use the default lock instead of retrying transactions + until their try_tbegin is zero. + */ + __builtin_tabort (_HTM_FIRST_USER_ABORT_CODE + 1); + } + + /* Only try a transaction if it's worth it. */ + if (*adapt_count <= 0) + { + unsigned status; + + if (__builtin_expect + ((status = __builtin_tbegin ((void *)0)) == _HTM_TBEGIN_STARTED, 1)) + { + if (*futex == 0) + return 0; + /* Lock was busy. Fall back to normal locking. */ + /* Since we are in a non-nested transaction there is no need to abort, + which is expensive. */ + __builtin_tend (); + /* Note: Changing the adapt_count here might abort a transaction on a + different cpu, but that could happen anyway when the futex is + acquired, so there's no need to check the nesting depth here. */ + if (aconf.skip_lock_busy > 0) + *adapt_count = aconf.skip_lock_busy; + } + else + { + asm volatile ("" ::: "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", + "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15", + "cc", "memory"); + if (status != _HTM_TBEGIN_TRANSIENT) + { + /* A persistent abort (cc 1 or 3) indicates that a retry is + probably futile. Use the normal locking now and for the + next couple of calls. + Be careful to avoid writing to the lock. */ + if (aconf.skip_trylock_internal_abort > 0) + *adapt_count = aconf.skip_trylock_internal_abort; + } + } + /* Could do some retries here. */ + } + else + { + /* Lost updates are possible, but harmless. Due to races this might lead + to *adapt_count becoming less than zero. */ + (*adapt_count)--; + } + + return lll_trylock (*futex); +} diff --git a/nptl/sysdeps/unix/sysv/linux/s390/elision-unlock.c b/nptl/sysdeps/unix/sysv/linux/s390/elision-unlock.c new file mode 100644 index 0000000..44d05cb --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/elision-unlock.c @@ -0,0 +1,38 @@ +/* Commit an elided pthread lock. + 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 + . */ + +#include +#include + +int +__lll_unlock_elision(int *lock, int private) +{ + /* If the lock is free, we elided the lock earlier. This does not + necessarily mean that we are in a transaction, because the user code may + have closed the transaction, but that is impossible to detect reliably. */ + if (*lock == 0) + { + __asm__ volatile (".machinemode \"zarch_nohighgprs\"\n\t" + ".machine \"all\"" + : : : "memory"); + __builtin_tend(); + } + else + lll_unlock ((*lock), private); + return 0; +} diff --git a/nptl/sysdeps/unix/sysv/linux/s390/force-elision.h b/nptl/sysdeps/unix/sysv/linux/s390/force-elision.h new file mode 100644 index 0000000..8fd7684 --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/force-elision.h @@ -0,0 +1,33 @@ +/* Automatic enabling of elision for mutexes + 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 + . */ + +#ifdef ENABLE_LOCK_ELISION +/* 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; \ + } +#endif diff --git a/nptl/sysdeps/unix/sysv/linux/s390/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/s390/lowlevellock.h index 864dcbc..3b6bc6e 100644 --- a/nptl/sysdeps/unix/sysv/linux/s390/lowlevellock.h +++ b/nptl/sysdeps/unix/sysv/linux/s390/lowlevellock.h @@ -285,6 +285,15 @@ __lll_timedlock (int *futex, const struct timespec *abstime, int private) #define lll_timedlock(futex, abstime, private) \ __lll_timedlock (&(futex), abstime, private) +#ifdef ENABLE_LOCK_ELISION +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) +#endif + static inline int __attribute__ ((always_inline)) __lll_robust_timedlock (int *futex, const struct timespec *abstime, @@ -360,4 +369,22 @@ extern int __lll_timedwait_tid (int *, const struct timespec *) __res; \ }) +#ifdef ENABLE_LOCK_ELISION +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 + #endif /* lowlevellock.h */ diff --git a/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_cond_lock.c b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_cond_lock.c new file mode 100644 index 0000000..6fc0f96 --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_cond_lock.c @@ -0,0 +1,22 @@ +/* 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 + . */ + +/* The cond lock is not actually elided yet, but we still need to handle + already elided locks. */ +#include + +#include diff --git a/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_lock.c b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_lock.c new file mode 100644 index 0000000..6fd6a98 --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_lock.c @@ -0,0 +1,22 @@ +/* Elided version of pthread_mutex_lock. + 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 + . */ + +#include +#include + +#include diff --git a/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_timedlock.c b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_timedlock.c new file mode 100644 index 0000000..d0e6537 --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_timedlock.c @@ -0,0 +1,22 @@ +/* Elided version of pthread_mutex_timedlock. + 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 + . */ + +#include +#include + +#include diff --git a/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_trylock.c b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_trylock.c new file mode 100644 index 0000000..ea8a8ff --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_trylock.c @@ -0,0 +1,22 @@ +/* Elided version of pthread_mutex_trylock. + 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 + . */ + +#include +#include + +#include diff --git a/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_unlock.c b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_unlock.c new file mode 100644 index 0000000..d244dca --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/s390/pthread_mutex_unlock.c @@ -0,0 +1,19 @@ +/* Elided version of pthread_mutex_trylock. + 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 + . */ + +#include diff --git a/sysdeps/s390/configure b/sysdeps/s390/configure index c2d05f7..6948cc2 100644 --- a/sysdeps/s390/configure +++ b/sysdeps/s390/configure @@ -68,5 +68,41 @@ if test $ac_verc_fail = yes; then fi + +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for __builtin_tbegin" >&5 +$as_echo_n "checking for __builtin_tbegin... " >&6; } +if ${libc_cv_gcc_builtin_tbegin+:} false; then : + $as_echo_n "(cached) " >&6 +else + cat > conftest.c <<\EOF +#include +void testtransaction () +{ + if (__builtin_tbegin (0) == _HTM_TBEGIN_STARTED) + { + __builtin_tend (); + } +} +EOF +if { ac_try='${CC-cc} -mhtm -O2 -S conftest.c -o - | grep -w tbegin > /dev/null' + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5 + (eval $ac_try) 2>&5 + ac_status=$? + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5 + test $ac_status = 0; }; } ; +then + libc_cv_gcc_builtin_tbegin=yes +else + libc_cv_gcc_builtin_tbegin=no +fi +rm -f conftest* +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_gcc_builtin_tbegin" >&5 +$as_echo "$libc_cv_gcc_builtin_tbegin" >&6; } + +if test "$enable_lock_elision" = yes && test "$libc_cv_gcc_builtin_tbegin" = no ; then + critic_missing="$critic_missing The used GCC has no support for __builtin_tbegin, which is needed for lock-elision on target S390." +fi + test -n "$critic_missing" && as_fn_error $? " *** $critic_missing" "$LINENO" 5 diff --git a/sysdeps/s390/configure.ac b/sysdeps/s390/configure.ac index 59cfdd1..493e9a4 100644 --- a/sysdeps/s390/configure.ac +++ b/sysdeps/s390/configure.ac @@ -10,5 +10,31 @@ AC_CHECK_PROG_VER(AS, $AS, --version, [GNU assembler.* \([0-9]*\.[0-9.]*\)], [2.2[4-9]*|2.[3-9][0-9]*|[3-9].*|[1-9][0-9]*], critic_missing="$critic_missing The program AS is required in version >= 2.24 for target S390.") + +AC_CACHE_CHECK(for __builtin_tbegin, libc_cv_gcc_builtin_tbegin, [dnl +cat > conftest.c <<\EOF +#include +void testtransaction () +{ + if (__builtin_tbegin (0) == _HTM_TBEGIN_STARTED) + { + __builtin_tend (); + } +} +EOF +dnl +dnl test, if the tbegin instruction is used by __builtin_tbegin +if AC_TRY_COMMAND([${CC-cc} -mhtm -O2 -S conftest.c -o - | grep -w tbegin > /dev/null]) ; +then + libc_cv_gcc_builtin_tbegin=yes +else + libc_cv_gcc_builtin_tbegin=no +fi +rm -f conftest* ]) + +if test "$enable_lock_elision" = yes && test "$libc_cv_gcc_builtin_tbegin" = no ; then + critic_missing="$critic_missing The used GCC has no support for __builtin_tbegin, which is needed for lock-elision on target S390." +fi + test -n "$critic_missing" && AC_MSG_ERROR([ *** $critic_missing])