From patchwork Tue Jun 10 16:15:43 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bernard Ogden X-Patchwork-Id: 1417 Received: (qmail 30641 invoked by alias); 10 Jun 2014 16:16:03 -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 30616 invoked by uid 89); 10 Jun 2014 16:16:01 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_LOW, SPF_PASS autolearn=ham version=3.3.2 X-HELO: mail-wi0-f174.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:content-type:mime-version:subject:from :in-reply-to:date:cc:content-transfer-encoding:message-id:references :to; bh=dj1s76acO80QKtipBi3K3gxGI1AH6+MCGAmJtVWq1B8=; b=i8jxamfJ1VPVjKLv6pbBfaiJI192SxzuhFsVAaW5Ty/wsltwVDFYXinHsFXF0S/Qd1 5E7VmBsFPlCVV4uTb7SffpeVISH1gEQGH8DCetJ4Ah22+Nd0wMlYwTvS6hfZFb0662P8 sL7Ucu4vqtBd50EZNmmrYb97uz8IaylJnlVS3BhCYf7Eh28ggUfzMbVmBu4tegksy10k CDd5m/GkpCj/H/0AS1JR8LifgnwLDlDyEL5VzuLvqxBEbVQDwuCbxBlH/NRiDSTnKtId +jCgA9iOpE2Cuht2BMyDd/kiaoU3msRyGh09SaBGVGVtoniIjbarFO3dmvA2xQVkOpx7 ONqw== X-Gm-Message-State: ALoCoQm3DdPwKPkXXEKObFpWvsx/qD3vNKFk3kLQsMwDi5B0qz6Aixnk0zhs60CANNbOFm8WNdC4 X-Received: by 10.194.71.81 with SMTP id s17mr43865783wju.10.1402416952928; Tue, 10 Jun 2014 09:15:52 -0700 (PDT) Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.2\)) Subject: Re: [PATCH 6/9][v2] Alpha - Remove alpha lowlevellock.h From: Bernard Ogden In-Reply-To: Date: Tue, 10 Jun 2014 17:15:43 +0100 Cc: libc-alpha@sourceware.org Message-Id: References: <41DCC830-45D9-462C-91DE-13AE4D648139@linaro.org> To: "Joseph S. Myers" Great. Here's a patch to remove it instead. I forgot to mention the changes this causes for alpha - lll_futex_timed_wait_bitset now mainpulates its return value through the usual macros - as callers do more than just compare return value to 0, it may have been a bug that it was not doing so before. lll_futex_timed_wait_requeue_pi now calls INTERNAL_SYSCALL_ERROR_P on the return value. This function only has one caller, and that caller just compares return value to 0, so the behaviour is equivalent. 2014-06-09 Bernard Ogden * sysdeps/unix/sysv/linux/alpha/lowlevellock.h: Remove file. On 9 Jun 2014, at 21:39, Joseph S. Myers wrote: > On Mon, 9 Jun 2014, Bernard Ogden wrote: > >> Simplify alpha lowlevellock.h >> >> alpha's lowlevellock.h defines NR_futex, so we keep it but reduce >> it to that define and an include-next to get the linux >> lowlevellock.h. > > But you don't need that definition. glibc assumes at least 2.6.32 kernel > (headers and at runtime), and 2.6.32 headers define __NR_futex for alpha. > Such definitions of syscall numbers in glibc are mostly redundant > nowadays. (nptl/sysdeps/i386/tls.h and > sysdeps/unix/sysv/linux/i386/clone.S are two more examples where such a > syscall number is defined, probably for convenience in building glibc when > the syscall was very new, but no longer need to be defined as long as the > files include the right headers.) > > -- > Joseph S. Myers > joseph@codesourcery.com diff --git a/sysdeps/unix/sysv/linux/alpha/lowlevellock.h b/sysdeps/unix/sysv/linux/alpha/lowlevellock.h deleted file mode 100644 index 361bd34..0000000 --- a/sysdeps/unix/sysv/linux/alpha/lowlevellock.h +++ /dev/null @@ -1,322 +0,0 @@ -/* Copyright (C) 2003-2014 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 - . */ - -#ifndef _LOWLEVELLOCK_H -#define _LOWLEVELLOCK_H 1 - -#include -#include -#include -#include -#include -#include - - -#define __NR_futex 394 -#define FUTEX_WAIT 0 -#define FUTEX_WAKE 1 -#define FUTEX_REQUEUE 3 -#define FUTEX_CMP_REQUEUE 4 -#define FUTEX_WAKE_OP 5 -#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE ((4 << 24) | 1) -#define FUTEX_LOCK_PI 6 -#define FUTEX_UNLOCK_PI 7 -#define FUTEX_TRYLOCK_PI 8 -#define FUTEX_WAIT_BITSET 9 -#define FUTEX_WAKE_BITSET 10 -#define FUTEX_WAIT_REQUEUE_PI 11 -#define FUTEX_CMP_REQUEUE_PI 12 -#define FUTEX_PRIVATE_FLAG 128 -#define FUTEX_CLOCK_REALTIME 256 - -#define FUTEX_BITSET_MATCH_ANY 0xffffffff - -/* Values for 'private' parameter of locking macros. Yes, the - definition seems to be backwards. But it is not. The bit will be - reversed before passing to the system call. */ -#define LLL_PRIVATE 0 -#define LLL_SHARED FUTEX_PRIVATE_FLAG - - -#if !defined NOT_IN_libc || defined IS_IN_rtld -/* In libc.so or ld.so all futexes are private. */ -# ifdef __ASSUME_PRIVATE_FUTEX -# define __lll_private_flag(fl, private) \ - ((fl) | FUTEX_PRIVATE_FLAG) -# else -# define __lll_private_flag(fl, private) \ - ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex)) -# endif -#else -# ifdef __ASSUME_PRIVATE_FUTEX -# define __lll_private_flag(fl, private) \ - (((fl) | FUTEX_PRIVATE_FLAG) ^ (private)) -# else -# define __lll_private_flag(fl, private) \ - (__builtin_constant_p (private) \ - ? ((private) == 0 \ - ? ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex)) \ - : (fl)) \ - : ((fl) | (((private) ^ FUTEX_PRIVATE_FLAG) \ - & THREAD_GETMEM (THREAD_SELF, header.private_futex)))) -# endif -#endif - - -#define lll_futex_wait(futexp, val, private) \ - lll_futex_timed_wait (futexp, val, NULL, private) - -#define lll_futex_timed_wait_bitset(futexp, val, timespec, clockbit, private) \ - ({ \ - INTERNAL_SYSCALL_DECL (__err); \ - long int __ret; \ - int __op = FUTEX_WAIT_BITSET | clockbit; \ - \ - __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp), \ - __lll_private_flag (__op, private), \ - (val), (timespec), NULL /* Unused. */, \ - FUTEX_BITSET_MATCH_ANY); \ - __ret; \ - }) - -#define lll_futex_timed_wait(futexp, val, timespec, private) \ - ({ \ - INTERNAL_SYSCALL_DECL (__err); \ - long int __ret; \ - __ret = INTERNAL_SYSCALL (futex, __err, 4, (futexp), \ - __lll_private_flag (FUTEX_WAIT, private), \ - (val), (timespec)); \ - INTERNAL_SYSCALL_ERROR_P (__ret, __err)? -__ret : __ret; \ - }) - -#define lll_futex_wake(futexp, nr, private) \ - ({ \ - INTERNAL_SYSCALL_DECL (__err); \ - long int __ret; \ - __ret = INTERNAL_SYSCALL (futex, __err, 4, (futexp), \ - __lll_private_flag (FUTEX_WAKE, private), \ - (nr), 0); \ - INTERNAL_SYSCALL_ERROR_P (__ret, __err)? -__ret : __ret; \ - }) - -#define lll_robust_dead(futexv, private) \ - do \ - { \ - int *__futexp = &(futexv); \ - atomic_or (__futexp, FUTEX_OWNER_DIED); \ - lll_futex_wake (__futexp, 1, private); \ - } \ - while (0) - -/* Returns non-zero if error happened, zero if success. */ -#define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val, private) \ - ({ \ - INTERNAL_SYSCALL_DECL (__err); \ - long int __ret; \ - __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp), \ - __lll_private_flag (FUTEX_CMP_REQUEUE, private),\ - (nr_wake), (nr_move), (mutex), (val)); \ - INTERNAL_SYSCALL_ERROR_P (__ret, __err); \ - }) - -/* Returns non-zero if error happened, zero if success. */ -#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2, private) \ - ({ \ - INTERNAL_SYSCALL_DECL (__err); \ - long int __ret; \ - __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp), \ - __lll_private_flag (FUTEX_WAKE_OP, private), \ - (nr_wake), (nr_wake2), (futexp2), \ - FUTEX_OP_CLEAR_WAKE_IF_GT_ONE); \ - INTERNAL_SYSCALL_ERROR_P (__ret, __err); \ - }) - -/* Priority Inheritance support. */ -#define lll_futex_wait_requeue_pi(futexp, val, mutex, private) \ - lll_futex_timed_wait_requeue_pi (futexp, val, NULL, 0, mutex, private) - -#define lll_futex_timed_wait_requeue_pi(futexp, val, timespec, clockbit, \ - mutex, private) \ - ({ \ - INTERNAL_SYSCALL_DECL (__err); \ - int __op = FUTEX_WAIT_REQUEUE_PI | clockbit; \ - \ - INTERNAL_SYSCALL (futex, __err, 5, (futexp), \ - __lll_private_flag (__op, private), \ - (val), (timespec), mutex); \ - }) - -#define lll_futex_cmp_requeue_pi(futexp, nr_wake, nr_move, mutex, val, priv) \ - ({ \ - INTERNAL_SYSCALL_DECL (__err); \ - long int __ret; \ - \ - __ret = INTERNAL_SYSCALL (futex, __err, 6, (futexp), \ - __lll_private_flag (FUTEX_CMP_REQUEUE_PI, priv),\ - (nr_wake), (nr_move), (mutex), (val)); \ - INTERNAL_SYSCALL_ERROR_P (__ret, __err); \ - }) - -static inline int __attribute__((always_inline)) -__lll_trylock(int *futex) -{ - return atomic_compare_and_exchange_val_acq (futex, 1, 0) != 0; -} -#define lll_trylock(lock) __lll_trylock (&(lock)) - - -static inline int __attribute__((always_inline)) -__lll_cond_trylock(int *futex) -{ - return atomic_compare_and_exchange_val_acq (futex, 2, 0) != 0; -} -#define lll_cond_trylock(lock) __lll_cond_trylock (&(lock)) - - -static inline int __attribute__((always_inline)) -__lll_robust_trylock(int *futex, int id) -{ - return atomic_compare_and_exchange_val_acq (futex, id, 0) != 0; -} -#define lll_robust_trylock(lock, id) \ - __lll_robust_trylock (&(lock), id) - -extern void __lll_lock_wait_private (int *futex) attribute_hidden; -extern void __lll_lock_wait (int *futex, int private) attribute_hidden; -extern int __lll_robust_lock_wait (int *futex, int private) attribute_hidden; - -static inline void __attribute__((always_inline)) -__lll_lock(int *futex, int private) -{ - if (atomic_compare_and_exchange_bool_acq (futex, 1, 0) != 0) - { - if (__builtin_constant_p (private) && private == LLL_PRIVATE) - __lll_lock_wait_private (futex); - else - __lll_lock_wait (futex, private); - } -} -#define lll_lock(futex, private) __lll_lock (&(futex), private) - - -static inline int __attribute__ ((always_inline)) -__lll_robust_lock (int *futex, int id, int private) -{ - int result = 0; - if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0) - result = __lll_robust_lock_wait (futex, private); - return result; -} -#define lll_robust_lock(futex, id, private) \ - __lll_robust_lock (&(futex), id, private) - - -static inline void __attribute__ ((always_inline)) -__lll_cond_lock (int *futex, int private) -{ - if (atomic_compare_and_exchange_bool_acq (futex, 2, 0) != 0) - __lll_lock_wait (futex, private); -} -#define lll_cond_lock(futex, private) __lll_cond_lock (&(futex), private) - - -#define lll_robust_cond_lock(futex, id, private) \ - __lll_robust_lock (&(futex), (id) | FUTEX_WAITERS, private) - - -extern int __lll_timedlock_wait (int *futex, const struct timespec *, - int private) attribute_hidden; -extern int __lll_robust_timedlock_wait (int *futex, const struct timespec *, - int private) attribute_hidden; - -static inline int __attribute__ ((always_inline)) -__lll_timedlock (int *futex, const struct timespec *abstime, int private) -{ - int result = 0; - if (atomic_compare_and_exchange_bool_acq (futex, 1, 0) != 0) - result = __lll_timedlock_wait (futex, abstime, private); - return result; -} -#define lll_timedlock(futex, abstime, private) \ - __lll_timedlock (&(futex), abstime, private) - - -static inline int __attribute__ ((always_inline)) -__lll_robust_timedlock (int *futex, const struct timespec *abstime, - int id, int private) -{ - int result = 0; - if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0) - result = __lll_robust_timedlock_wait (futex, abstime, private); - return result; -} -#define lll_robust_timedlock(futex, abstime, id, private) \ - __lll_robust_timedlock (&(futex), abstime, id, private) - - -#define __lll_unlock(futex, private) \ - (void) \ - ({ int *__futex = (futex); \ - int __oldval = atomic_exchange_rel (__futex, 0); \ - if (__builtin_expect (__oldval > 1, 0)) \ - lll_futex_wake (__futex, 1, private); \ - }) -#define lll_unlock(futex, private) __lll_unlock(&(futex), private) - - -#define __lll_robust_unlock(futex, private) \ - (void) \ - ({ int *__futex = (futex); \ - int __oldval = atomic_exchange_rel (__futex, 0); \ - if (__builtin_expect (__oldval & FUTEX_WAITERS, 0)) \ - lll_futex_wake (__futex, 1, private); \ - }) -#define lll_robust_unlock(futex, private) \ - __lll_robust_unlock(&(futex), private) - - -#define lll_islocked(futex) \ - (futex != 0) - -/* Initializers for lock. */ -#define LLL_LOCK_INITIALIZER (0) -#define LLL_LOCK_INITIALIZER_LOCKED (1) - - -/* The kernel notifies a process which uses CLONE_CHILD_CLEARTID via futex - wakeup when the clone terminates. The memory location contains the - thread ID while the clone is running and is reset to zero - afterwards. */ -#define lll_wait_tid(tid) \ - do { \ - __typeof (tid) __tid; \ - while ((__tid = (tid)) != 0) \ - lll_futex_wait (&(tid), __tid, LLL_SHARED); \ - } while (0) - -extern int __lll_timedwait_tid (int *, const struct timespec *) - attribute_hidden; - -#define lll_timedwait_tid(tid, abstime) \ - ({ \ - int __res = 0; \ - if ((tid) != 0) \ - __res = __lll_timedwait_tid (&(tid), (abstime)); \ - __res; \ - }) - -#endif /* lowlevellock.h */