From nobody Thu May 2 17:42:18 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1571075769; cv=none; d=zoho.com; s=zohoarc; b=n/bEibtVozKeAI2uPyU8ONs2RcqWpUCU9fNowqF0bXfMSrht7la8XXtDXtIqT7kFOf73OoRXbuR04c3k9Hx9RBhwxquORzu7fIbFkje8v3SsvW6YvNM82TISewUAddSLt/y2Ucg7LJIS+9razzVGsIYMC7o1MTg1rvE3ir/sTWE= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1571075769; h=Content-Transfer-Encoding:Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Sender:Subject:To; bh=q5XiGkSacx1wHC2r0wphBN/pgHvk1SDo7w0TZK1ILE0=; b=lOFvJ7b1oBt+5+tmJInM3/Gzyfbokgh1kRHzEO8ynismM7AC51Bwy4nsAImzwi9EvGagxkC0MXUSYjn3OS7/nffAQj/k2AHgBfamtMmrDXX/Ri0XWgns3hrrVC/D5/+3fBaFHzk3hhy2s6DsXvsxPvf5dL3sY31Wg5rYYTPAILI= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 157107576986165.89642466201167; Mon, 14 Oct 2019 10:56:09 -0700 (PDT) Received: from localhost ([::1]:55086 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iK4Zj-00014b-QD for importer@patchew.org; Mon, 14 Oct 2019 13:56:08 -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+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" 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 Reviewed-by: Stefan Hajnoczi --- 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 e= nable) 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 e= nable) /* Expose avail event/used flags before caller checks the avail id= x. */ 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 count) 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, unsigned = 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 *vdev= , 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, int = 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, int = 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