From owner-svn-src-all@freebsd.org Sun Apr 22 09:30:08 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A5FA3FAED7C; Sun, 22 Apr 2018 09:30:08 +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 2FB2C78E2E; Sun, 22 Apr 2018 09:30:08 +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 2AB7413F9E; Sun, 22 Apr 2018 09:30:08 +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 w3M9U7Di051991; Sun, 22 Apr 2018 09:30:07 GMT (envelope-from mjg@FreeBSD.org) Received: (from mjg@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w3M9U788051989; Sun, 22 Apr 2018 09:30:07 GMT (envelope-from mjg@FreeBSD.org) Message-Id: <201804220930.w3M9U788051989@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mjg set sender to mjg@FreeBSD.org using -f From: Mateusz Guzik Date: Sun, 22 Apr 2018 09:30:07 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r332870 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: mjg X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 332870 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: Sun, 22 Apr 2018 09:30:08 -0000 Author: mjg Date: Sun Apr 22 09:30:07 2018 New Revision: 332870 URL: https://svnweb.freebsd.org/changeset/base/332870 Log: lockf: slightly depessimize 1. check if P_ADVLOCK is already set and if so, don't lock to set it (stolen from DragonFly) 2. when trying for fast path unlock, check that we are doing unlock first instead of taking the interlock for no reason (e.g. if we want to *lock*). whilere make it more likely that falling fast path will not take the interlock either by checking for state Note the code is severely pessimized both single- and multithreaded. Modified: head/sys/kern/kern_descrip.c head/sys/kern/kern_lockf.c Modified: head/sys/kern/kern_descrip.c ============================================================================== --- head/sys/kern/kern_descrip.c Sun Apr 22 06:11:46 2018 (r332869) +++ head/sys/kern/kern_descrip.c Sun Apr 22 09:30:07 2018 (r332870) @@ -648,9 +648,11 @@ kern_fcntl(struct thread *td, int fd, int cmd, intptr_ error = EBADF; break; } - PROC_LOCK(p->p_leader); - p->p_leader->p_flag |= P_ADVLOCK; - PROC_UNLOCK(p->p_leader); + if ((p->p_leader->p_flag & P_ADVLOCK) == 0) { + PROC_LOCK(p->p_leader); + p->p_leader->p_flag |= P_ADVLOCK; + PROC_UNLOCK(p->p_leader); + } error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, flp, flg); break; @@ -659,9 +661,11 @@ kern_fcntl(struct thread *td, int fd, int cmd, intptr_ error = EBADF; break; } - PROC_LOCK(p->p_leader); - p->p_leader->p_flag |= P_ADVLOCK; - PROC_UNLOCK(p->p_leader); + if ((p->p_leader->p_flag & P_ADVLOCK) == 0) { + PROC_LOCK(p->p_leader); + p->p_leader->p_flag |= P_ADVLOCK; + PROC_UNLOCK(p->p_leader); + } error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, flp, flg); break; Modified: head/sys/kern/kern_lockf.c ============================================================================== --- head/sys/kern/kern_lockf.c Sun Apr 22 06:11:46 2018 (r332869) +++ head/sys/kern/kern_lockf.c Sun Apr 22 09:30:07 2018 (r332870) @@ -479,15 +479,15 @@ retry_setlock: /* * Avoid the common case of unlocking when inode has no locks. */ - VI_LOCK(vp); - if ((*statep) == NULL) { - if (ap->a_op != F_SETLK) { + if (ap->a_op != F_SETLK && (*statep) == NULL) { + VI_LOCK(vp); + if ((*statep) == NULL) { fl->l_type = F_UNLCK; VI_UNLOCK(vp); return (0); } + VI_UNLOCK(vp); } - VI_UNLOCK(vp); /* * Map our arguments to an existing lock owner or create one