From patchwork Tue Mar 25 23:36:36 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Myers X-Patchwork-Id: 333747 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org 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 ozlabs.org (Postfix) with ESMTPS id 745BB14009E for ; Wed, 26 Mar 2014 10:36:51 +1100 (EST) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:date:from:to:cc:subject:in-reply-to:message-id :references:mime-version:content-type; q=dns; s=default; b=ZxBbu +36HY8SQyyV8Sl0bMSAiytfdXVq0nLDPyhd1cc37TGxcRo1d97+MJl2IneiJmwHL /dQ15DBA/ttUK+uO3fmqlnTzC0vlTJnRXsNeI5smnroP5ycLckQaTOZAFTAkGvF9 14cRV+P207hwBwXvWsLvwn3fAoWtHvRD+F3jZ8= 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:date:from:to:cc:subject:in-reply-to:message-id :references:mime-version:content-type; s=default; bh=mSeb6BtTvPj nKL562P/jzh+XkX0=; b=QAsql9TGcZpVu3/TxKWpk55FGzpbN7McQKO83XBJnYd q9hRXl8dxogSxl9EiyiHhgGmX8G0wlBtAGAsrmThaEgDW0DhrHfgqNpKd8qCM+fq WHlgHNNgpTQoyb9GebNyqL+9jyD7kYjvoqegd0PS5zkMwYFtzZnM9x2i+FCX5ga8 = Received: (qmail 14885 invoked by alias); 25 Mar 2014 23:36:46 -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 14874 invoked by uid 89); 25 Mar 2014 23:36:45 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL, BAYES_00 autolearn=ham version=3.3.2 X-HELO: relay1.mentorg.com Date: Tue, 25 Mar 2014 23:36:36 +0000 From: "Joseph S. Myers" To: David Miller CC: , , , Subject: Re: Correct robust mutex / PI futex kernel assumptions (bug 9894) In-Reply-To: <20140325.192428.254241380718352578.davem@davemloft.net> Message-ID: References: <20140325.190632.1279135735148309574.davem@davemloft.net> <20140325.192428.254241380718352578.davem@davemloft.net> MIME-Version: 1.0 On Tue, 25 Mar 2014, David Miller wrote: > From: "Joseph S. Myers" > Date: Tue, 25 Mar 2014 23:20:00 +0000 > > > On Tue, 25 Mar 2014, David Miller wrote: > > > >> Actually, it turns out you can simply test for the CPP macro __sparc_v9__ > > > > In that case, here is a revised patch using __sparc_v9__ in place of > > __arch64__. > > It only get's set for 32-bit v9, you'll need to keep the > (__sparc__ && __arch64__) in an "||" conditional branch. > > Something like (__sparc__ && (__arch64__ || __sparc_v9__)) Here's a third patch version. 2014-03-25 Joseph Myers [BZ #9894] * sysdeps/unix/sysv/linux/kernel-features.h [__sparc__ && !__arch64__ && !__sparc_v9__] (__ASSUME_SET_ROBUST_LIST): Do not define. [__sparc__ && !__arch64__ && !__sparc_v9__] (__ASSUME_FUTEX_LOCK_PI): Likewise. [__sparc__ && !__arch64__ && !__sparc_v9__] (__ASSUME_REQUEUE_PI): Likewise. * sysdeps/unix/sysv/linux/arm/kernel-features.h (__ASSUME_FUTEX_LOCK_PI): Undefine. (__ASSUME_REQUEUE_PI): Likewise. (__ASSUME_SET_ROBUST_LIST): Likewise. * sysdeps/unix/sysv/linux/m68k/kernel-features.h [__LINUX_KERNEL_VERSION < 0x030a00] (__ASSUME_FUTEX_LOCK_PI): Undefine. * sysdeps/unix/sysv/linux/microblaze/kernel-features.h [__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_FUTEX_LOCK_PI): Likewise. [__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_REQUEUE_PI): Likewise. [__LINUX_KERNEL_VERSION < 0x020621] (__ASSUME_SET_ROBUST_LIST): Likewise. * sysdeps/unix/sysv/linux/mips/kernel-features.h [__mips == 1 || _MIPS_ARCH_R5900] (__ASSUME_FUTEX_LOCK_PI): Undefine. [__mips == 1 || _MIPS_ARCH_R5900] (__ASSUME_REQUEUE_PI): Likewise. [__mips == 1 || _MIPS_ARCH_R5900] (__ASSUME_SET_ROBUST_LIST): Likewise. diff --git a/sysdeps/unix/sysv/linux/arm/kernel-features.h b/sysdeps/unix/sysv/linux/arm/kernel-features.h index 401343b..96b7350 100644 --- a/sysdeps/unix/sysv/linux/arm/kernel-features.h +++ b/sysdeps/unix/sysv/linux/arm/kernel-features.h @@ -53,3 +53,10 @@ # undef __ASSUME_PSELECT # undef __ASSUME_PPOLL #endif + +/* The ARM kernel may or may not support + futex_atomic_cmpxchg_inatomic, depending on kernel + configuration. */ +#undef __ASSUME_FUTEX_LOCK_PI +#undef __ASSUME_REQUEUE_PI +#undef __ASSUME_SET_ROBUST_LIST diff --git a/sysdeps/unix/sysv/linux/kernel-features.h b/sysdeps/unix/sysv/linux/kernel-features.h index 555b82c..db6af35 100644 --- a/sysdeps/unix/sysv/linux/kernel-features.h +++ b/sysdeps/unix/sysv/linux/kernel-features.h @@ -106,9 +106,12 @@ # define __ASSUME_ATFCTS 1 #endif -/* Support for inter-process robust mutexes was added in 2.6.17. */ +/* Support for inter-process robust mutexes was added in 2.6.17 (but + some architectures lack futex_atomic_cmpxchg_inatomic in some + configurations). */ #if __LINUX_KERNEL_VERSION >= 0x020611 \ - && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020613) + && (!defined __sh__ || __LINUX_KERNEL_VERSION >= 0x020613) \ + && !(defined __sparc__ && !defined __arch64__ && !defined __sparc_v9__) # define __ASSUME_SET_ROBUST_LIST 1 #endif @@ -119,8 +122,10 @@ # define __ASSUME_COMPLETE_READV_WRITEV 1 #endif -/* Support for PI futexes was added in 2.6.18. */ -#if __LINUX_KERNEL_VERSION >= 0x020612 +/* Support for PI futexes was added in 2.6.18 (but some architectures + lack futex_atomic_cmpxchg_inatomic in some configurations). */ +#if __LINUX_KERNEL_VERSION >= 0x020612 \ + && !(defined __sparc__ && !defined __arch64__ && !defined __sparc_v9__) # define __ASSUME_FUTEX_LOCK_PI 1 #endif @@ -223,8 +228,11 @@ # define __ASSUME_PWRITEV 1 #endif -/* Support for FUTEX_*_REQUEUE_PI was added in 2.6.31. */ -#if __LINUX_KERNEL_VERSION >= 0x02061f +/* Support for FUTEX_*_REQUEUE_PI was added in 2.6.31 (but some + architectures lack futex_atomic_cmpxchg_inatomic in some + configurations). */ +#if __LINUX_KERNEL_VERSION >= 0x02061f \ + && !(defined __sparc__ && !defined __arch64__ && !defined __sparc_v9__) # define __ASSUME_REQUEUE_PI 1 #endif diff --git a/sysdeps/unix/sysv/linux/m68k/kernel-features.h b/sysdeps/unix/sysv/linux/m68k/kernel-features.h index cb8915f..bc340bd 100644 --- a/sysdeps/unix/sysv/linux/m68k/kernel-features.h +++ b/sysdeps/unix/sysv/linux/m68k/kernel-features.h @@ -48,6 +48,7 @@ /* No support for PI futexes or robust mutexes before 3.10 for m68k. */ #if __LINUX_KERNEL_VERSION < 0x030a00 +# undef __ASSUME_FUTEX_LOCK_PI # undef __ASSUME_REQUEUE_PI # undef __ASSUME_SET_ROBUST_LIST #endif diff --git a/sysdeps/unix/sysv/linux/microblaze/kernel-features.h b/sysdeps/unix/sysv/linux/microblaze/kernel-features.h index f9a61a9..a62b839 100644 --- a/sysdeps/unix/sysv/linux/microblaze/kernel-features.h +++ b/sysdeps/unix/sysv/linux/microblaze/kernel-features.h @@ -43,6 +43,13 @@ #include_next +/* Support for futex_atomic_cmpxchg_inatomic was added in 2.6.33. */ +#if __LINUX_KERNEL_VERSION < 0x020621 +# undef __ASSUME_FUTEX_LOCK_PI +# undef __ASSUME_REQUEUE_PI +# undef __ASSUME_SET_ROBUST_LIST +#endif + /* The MicroBlaze kernel does not support the pselect6, preadv and pwritev syscalls. */ #undef __ASSUME_PSELECT diff --git a/sysdeps/unix/sysv/linux/mips/kernel-features.h b/sysdeps/unix/sysv/linux/mips/kernel-features.h index 52cbf3a..19d3cba 100644 --- a/sysdeps/unix/sysv/linux/mips/kernel-features.h +++ b/sysdeps/unix/sysv/linux/mips/kernel-features.h @@ -53,3 +53,11 @@ #if _MIPS_SIM == _ABIN32 && __LINUX_KERNEL_VERSION < 0x020623 # undef __ASSUME_GETDENTS64_SYSCALL #endif + +/* The MIPS kernel does not support futex_atomic_cmpxchg_inatomic if + emulating LL/SC. */ +#if __mips == 1 || defined _MIPS_ARCH_R5900 +# undef __ASSUME_FUTEX_LOCK_PI +# undef __ASSUME_REQUEUE_PI +# undef __ASSUME_SET_ROBUST_LIST +#endif