From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 60554C4CECE for ; Mon, 14 Oct 2019 17:56:08 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3C70220873 for ; Mon, 14 Oct 2019 17:56:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3C70220873 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:55086 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iK4Zh-00014b-DB for qemu-devel@archiver.kernel.org; Mon, 14 Oct 2019 13:56:05 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52566) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iK4YW-0008R8-Sq for qemu-devel@nongnu.org; Mon, 14 Oct 2019 13:54:54 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iK4YU-0006ct-B7 for qemu-devel@nongnu.org; Mon, 14 Oct 2019 13:54:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51074) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iK4YU-0006cW-3D for qemu-devel@nongnu.org; Mon, 14 Oct 2019 13:54:50 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BC8D610CC203 for ; Mon, 14 Oct 2019 17:54:48 +0000 (UTC) Received: from dgilbert-t580.localhost (unknown [10.36.118.31]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1FF72608C2; Mon, 14 Oct 2019 17:54:42 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, mst@redhat.com Subject: [PATCH] virito: Use auto rcu_read macros Date: Mon, 14 Oct 2019 18:54:40 +0100 Message-Id: <20191014175440.152609-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.65]); Mon, 14 Oct 2019 17:54:48 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: stefanha@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: "Dr. David Alan Gilbert" Use RCU_READ_LOCK_GUARD and WITH_RCU_READ_LOCK_GUARD to replace the manual rcu_read_(un)lock calls. I think the only change is virtio_load which was missing unlocks in error paths; those end up being fatal errors so it's not that important anyway. Signed-off-by: Dr. David Alan Gilbert --- hw/virtio/virtio.c | 46 ++++++++++++++++------------------------------ 1 file changed, 16 insertions(+), 30 deletions(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 527df03bfd..15ae9da60b 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -337,7 +337,7 @@ void virtio_queue_set_notification(VirtQueue *vq, int= enable) return; } =20 - rcu_read_lock(); + RCU_READ_LOCK_GUARD(); if (virtio_vdev_has_feature(vq->vdev, VIRTIO_RING_F_EVENT_IDX)) { vring_set_avail_event(vq, vring_avail_idx(vq)); } else if (enable) { @@ -349,7 +349,6 @@ void virtio_queue_set_notification(VirtQueue *vq, int= enable) /* Expose avail event/used flags before caller checks the avail = idx. */ smp_mb(); } - rcu_read_unlock(); } =20 int virtio_queue_ready(VirtQueue *vq) @@ -393,9 +392,8 @@ int virtio_queue_empty(VirtQueue *vq) return 0; } =20 - rcu_read_lock(); + RCU_READ_LOCK_GUARD(); empty =3D vring_avail_idx(vq) =3D=3D vq->last_avail_idx; - rcu_read_unlock(); return empty; } =20 @@ -530,10 +528,9 @@ void virtqueue_flush(VirtQueue *vq, unsigned int cou= nt) void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem, unsigned int len) { - rcu_read_lock(); + RCU_READ_LOCK_GUARD(); virtqueue_fill(vq, elem, len, 0); virtqueue_flush(vq, 1); - rcu_read_unlock(); } =20 /* Called within rcu_read_lock(). */ @@ -624,7 +621,7 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigne= d int *in_bytes, return; } =20 - rcu_read_lock(); + RCU_READ_LOCK_GUARD(); idx =3D vq->last_avail_idx; total_bufs =3D in_total =3D out_total =3D 0; =20 @@ -719,7 +716,6 @@ done: if (out_bytes) { *out_bytes =3D out_total; } - rcu_read_unlock(); return; =20 err: @@ -869,7 +865,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) if (unlikely(vdev->broken)) { return NULL; } - rcu_read_lock(); + RCU_READ_LOCK_GUARD(); if (virtio_queue_empty_rcu(vq)) { goto done; } @@ -977,7 +973,6 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz) trace_virtqueue_pop(vq, elem, elem->in_num, elem->out_num); done: address_space_cache_destroy(&indirect_desc_cache); - rcu_read_unlock(); =20 return elem; =20 @@ -1680,13 +1675,10 @@ static bool virtio_should_notify(VirtIODevice *vd= ev, VirtQueue *vq) =20 void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq) { - bool should_notify; - rcu_read_lock(); - should_notify =3D virtio_should_notify(vdev, vq); - rcu_read_unlock(); - - if (!should_notify) { - return; + WITH_RCU_READ_LOCK_GUARD() { + if (!virtio_should_notify(vdev, vq)) { + return; + } } =20 trace_virtio_notify_irqfd(vdev, vq); @@ -1718,13 +1710,10 @@ static void virtio_irq(VirtQueue *vq) =20 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq) { - bool should_notify; - rcu_read_lock(); - should_notify =3D virtio_should_notify(vdev, vq); - rcu_read_unlock(); - - if (!should_notify) { - return; + WITH_RCU_READ_LOCK_GUARD() { + if (!virtio_should_notify(vdev, vq)) { + return; + } } =20 trace_virtio_notify(vdev, vq); @@ -2241,7 +2230,7 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, in= t version_id) vdev->start_on_kick =3D true; } =20 - rcu_read_lock(); + RCU_READ_LOCK_GUARD(); for (i =3D 0; i < num; i++) { if (vdev->vq[i].vring.desc) { uint16_t nheads; @@ -2289,7 +2278,6 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, in= t version_id) } } } - rcu_read_unlock(); =20 return 0; } @@ -2422,21 +2410,19 @@ void virtio_queue_set_last_avail_idx(VirtIODevice= *vdev, int n, uint16_t idx) =20 void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) { - rcu_read_lock(); + RCU_READ_LOCK_GUARD(); if (vdev->vq[n].vring.desc) { vdev->vq[n].last_avail_idx =3D vring_used_idx(&vdev->vq[n]); vdev->vq[n].shadow_avail_idx =3D vdev->vq[n].last_avail_idx; } - rcu_read_unlock(); } =20 void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) { - rcu_read_lock(); + RCU_READ_LOCK_GUARD(); if (vdev->vq[n].vring.desc) { vdev->vq[n].used_idx =3D vring_used_idx(&vdev->vq[n]); } - rcu_read_unlock(); } =20 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n) --=20 2.23.0