From nobody Thu May 2 15:00:11 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) client-ip=209.132.183.28; envelope-from=libvir-list-bounces@redhat.com; helo=mx1.redhat.com; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of redhat.com designates 209.132.183.28 as permitted sender) smtp.mailfrom=libvir-list-bounces@redhat.com Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by mx.zohomail.com with SMTPS id 1500972259603879.4470242509011; Tue, 25 Jul 2017 01:44:19 -0700 (PDT) Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0C187C0D804C; Tue, 25 Jul 2017 08:44:12 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8E2B98E82B; Tue, 25 Jul 2017 08:44:09 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 9F4C0180597C; Tue, 25 Jul 2017 08:44:03 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id v6P8hxHc025294 for ; Tue, 25 Jul 2017 04:43:59 -0400 Received: by smtp.corp.redhat.com (Postfix) id 516E48D573; Tue, 25 Jul 2017 08:43:59 +0000 (UTC) Received: from moe.brq.redhat.com (unknown [10.43.2.192]) by smtp.corp.redhat.com (Postfix) with ESMTP id CE8B38F341 for ; Tue, 25 Jul 2017 08:43:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 0C187C0D804C Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=libvir-list-bounces@redhat.com From: Michal Privoznik To: libvir-list@redhat.com Date: Tue, 25 Jul 2017 10:43:50 +0200 Message-Id: <442bf49a5959df6e919e5434e5396ed9593a4b33.1500972230.git.mprivozn@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-loop: libvir-list@redhat.com Subject: [libvirt] [PATCH] Revert "virthread: Introduce virRWLockInitPreferWriter" X-BeenThere: libvir-list@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: Development discussions about the libvirt library & tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: libvir-list-bounces@redhat.com Errors-To: libvir-list-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Tue, 25 Jul 2017 08:44:17 +0000 (UTC) X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" This reverts commit 328bd24443d2a345a5832ee48ebba0208f8036ea. As it turns out, this is not portable and very Linux & glibc specific. Worse, this may lead to not starving writers on Linux but everywhere else. Revert this and if the starvation occurs resolve it. Signed-off-by: Michal Privoznik Reviewed-by: Daniel P. Berrange --- src/libvirt_private.syms | 1 - src/util/virobject.c | 2 +- src/util/virthread.c | 35 ----------------------------------- src/util/virthread.h | 1 - 4 files changed, 1 insertion(+), 38 deletions(-) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 3cc6f4c6e..d98417678 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -2733,7 +2733,6 @@ virMutexUnlock; virOnce; virRWLockDestroy; virRWLockInit; -virRWLockInitPreferWriter; virRWLockRead; virRWLockUnlock; virRWLockWrite; diff --git a/src/util/virobject.c b/src/util/virobject.c index 4236abfef..b1bb378b4 100644 --- a/src/util/virobject.c +++ b/src/util/virobject.c @@ -275,7 +275,7 @@ virObjectRWLockableNew(virClassPtr klass) if (!(obj =3D virObjectNew(klass))) return NULL; =20 - if (virRWLockInitPreferWriter(&obj->lock) < 0) { + if (virRWLockInit(&obj->lock) < 0) { virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("Unable to initialize RW lock")); virObjectUnref(obj); diff --git a/src/util/virthread.c b/src/util/virthread.c index a8dd72f8b..6c495158f 100644 --- a/src/util/virthread.c +++ b/src/util/virthread.c @@ -95,15 +95,6 @@ void virMutexUnlock(virMutexPtr m) } =20 =20 -/** - * virRWLockInit: - * @m: rwlock to init - * - * Initializes RW lock using pthread default attributes (which - * is PTHREAD_RWLOCK_PREFER_READER_NP). - * - * Returns 0 on success, -1 otherwise. - */ int virRWLockInit(virRWLockPtr m) { int ret; @@ -115,32 +106,6 @@ int virRWLockInit(virRWLockPtr m) return 0; } =20 - -/** - * virRWLockInitPreferWriter: - * @m: rwlock to init - * - * Initializes RW lock which prefers writers over readers. - * - * Returns 0 on success, -1 otherwise. - */ -int virRWLockInitPreferWriter(virRWLockPtr m) -{ - int ret; - pthread_rwlockattr_t attr; - - pthread_rwlockattr_init(&attr); - pthread_rwlockattr_setkind_np(&attr, PTHREAD_RWLOCK_PREFER_WRITER_NONR= ECURSIVE_NP); - ret =3D pthread_rwlock_init(&m->lock, &attr); - pthread_rwlockattr_destroy(&attr); - if (ret !=3D 0) { - errno =3D ret; - return -1; - } - return 0; -} - - void virRWLockDestroy(virRWLockPtr m) { pthread_rwlock_destroy(&m->lock); diff --git a/src/util/virthread.h b/src/util/virthread.h index 18b785af2..e466d9bf0 100644 --- a/src/util/virthread.h +++ b/src/util/virthread.h @@ -136,7 +136,6 @@ void virMutexUnlock(virMutexPtr m); =20 =20 int virRWLockInit(virRWLockPtr m) ATTRIBUTE_RETURN_CHECK; -int virRWLockInitPreferWriter(virRWLockPtr m) ATTRIBUTE_RETURN_CHECK; void virRWLockDestroy(virRWLockPtr m); =20 void virRWLockRead(virRWLockPtr m); --=20 2.13.0 -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list