From owner-svn-src-all@freebsd.org Thu Oct 19 00:38:15 2017 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 8863FE47DC7; Thu, 19 Oct 2017 00:38:15 +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 mx1.freebsd.org (Postfix) with ESMTPS id 494E77039E; Thu, 19 Oct 2017 00:38:15 +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 v9J0cEbj033511; Thu, 19 Oct 2017 00:38:14 GMT (envelope-from mjg@FreeBSD.org) Received: (from mjg@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id v9J0cEQ1033510; Thu, 19 Oct 2017 00:38:14 GMT (envelope-from mjg@FreeBSD.org) Message-Id: <201710190038.v9J0cEQ1033510@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mjg set sender to mjg@FreeBSD.org using -f From: Mateusz Guzik Date: Thu, 19 Oct 2017 00:38:14 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r324734 - head/sys/kern X-SVN-Group: head X-SVN-Commit-Author: mjg X-SVN-Commit-Paths: head/sys/kern X-SVN-Commit-Revision: 324734 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: 2.1.23 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: Thu, 19 Oct 2017 00:38:15 -0000 Author: mjg Date: Thu Oct 19 00:38:14 2017 New Revision: 324734 URL: https://svnweb.freebsd.org/changeset/base/324734 Log: Tidy up pmc support at execve. The proc-specific check is inherently racy, so the code can just unlock beforehand. MFC after: 1 week Modified: head/sys/kern/kern_exec.c Modified: head/sys/kern/kern_exec.c ============================================================================== --- head/sys/kern/kern_exec.c Thu Oct 19 00:31:00 2017 (r324733) +++ head/sys/kern/kern_exec.c Thu Oct 19 00:38:14 2017 (r324734) @@ -849,28 +849,23 @@ interpret: p->p_args = newargs; newargs = NULL; + PROC_UNLOCK(p); + #ifdef HWPMC_HOOKS /* * Check if system-wide sampling is in effect or if the * current process is using PMCs. If so, do exec() time * processing. This processing needs to happen AFTER the * P_INEXEC flag is cleared. - * - * The proc lock needs to be released before taking the PMC - * SX. */ if (PMC_SYSTEM_SAMPLING_ACTIVE() || PMC_PROC_IS_USING_PMCS(p)) { - PROC_UNLOCK(p); VOP_UNLOCK(imgp->vp, 0); pe.pm_credentialschanged = credential_changing; pe.pm_entryaddr = imgp->entry_addr; PMC_CALL_HOOK_X(td, PMC_FN_PROCESS_EXEC, (void *) &pe); vn_lock(imgp->vp, LK_SHARED | LK_RETRY); - } else - PROC_UNLOCK(p); -#else /* !HWPMC_HOOKS */ - PROC_UNLOCK(p); + } #endif /* Set values passed into the program in registers. */