From owner-svn-src-all@freebsd.org Fri Jan 12 13:40:51 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 91666E6526F; Fri, 12 Jan 2018 13:40:51 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 6DDD669F80; Fri, 12 Jan 2018 13:40:51 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id C6DFD2451F; Fri, 12 Jan 2018 13:40:50 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id w0CDeoMF046645; Fri, 12 Jan 2018 13:40:50 GMT (envelope-from mjg@FreeBSD.org) Received: (from mjg@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w0CDeoI9046644; Fri, 12 Jan 2018 13:40:50 GMT (envelope-from mjg@FreeBSD.org) Message-Id: <201801121340.w0CDeoI9046644@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mjg set sender to mjg@FreeBSD.org using -f From: Mateusz Guzik Date: Fri, 12 Jan 2018 13:40:50 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r327875 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: mjg X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 327875 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Jan 2018 13:40:51 -0000 Author: mjg Date: Fri Jan 12 13:40:50 2018 New Revision: 327875 URL: https://svnweb.freebsd.org/changeset/base/327875 Log: mtx: use fcmpset to cover setting MTX_CONTESTED Modified: head/sys/kern/kern_mutex.c Modified: head/sys/kern/kern_mutex.c ============================================================================== --- head/sys/kern/kern_mutex.c Fri Jan 12 13:39:02 2018 (r327874) +++ head/sys/kern/kern_mutex.c Fri Jan 12 13:40:50 2018 (r327875) @@ -578,6 +578,7 @@ __mtx_lock_sleep(volatile uintptr_t *c, uintptr_t v) ts = turnstile_trywait(&m->lock_object); v = MTX_READ_VALUE(m); +retry_turnstile: /* * Check if the lock has been released while spinning for @@ -609,10 +610,8 @@ __mtx_lock_sleep(volatile uintptr_t *c, uintptr_t v) * or the state of the MTX_RECURSED bit changed. */ if ((v & MTX_CONTESTED) == 0 && - !atomic_cmpset_ptr(&m->mtx_lock, v, v | MTX_CONTESTED)) { - turnstile_cancel(ts); - v = MTX_READ_VALUE(m); - continue; + !atomic_fcmpset_ptr(&m->mtx_lock, &v, v | MTX_CONTESTED)) { + goto retry_turnstile; } /*