From patchwork Thu Jan 14 10:33:37 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vadim Rozenfeld X-Patchwork-Id: 42867 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 50B24B7CDB for ; Thu, 14 Jan 2010 21:42:19 +1100 (EST) Received: from localhost ([127.0.0.1]:46178 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NVN3i-0000H0-NU for incoming@patchwork.ozlabs.org; Thu, 14 Jan 2010 05:36:10 -0500 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NVN1g-0000Eh-4C for qemu-devel@nongnu.org; Thu, 14 Jan 2010 05:34:04 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NVN1b-00007K-Un for qemu-devel@nongnu.org; Thu, 14 Jan 2010 05:34:03 -0500 Received: from [199.232.76.173] (port=38562 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NVN1b-00006w-Ei for qemu-devel@nongnu.org; Thu, 14 Jan 2010 05:33:59 -0500 Received: from mx1.redhat.com ([209.132.183.28]:37107) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NVN1a-0003o1-PB for qemu-devel@nongnu.org; Thu, 14 Jan 2010 05:33:59 -0500 Received: from int-mx04.intmail.prod.int.phx2.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.17]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o0EAXu0t021120 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 14 Jan 2010 05:33:56 -0500 Received: from [10.35.6.69] (vpn-6-69.tlv.redhat.com [10.35.6.69]) by int-mx04.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o0EAXs7H020738; Thu, 14 Jan 2010 05:33:54 -0500 From: Vadim Rozenfeld To: qemu-devel Date: Thu, 14 Jan 2010 12:33:37 +0200 Message-Id: <1263465217.7273.74.camel@localhost> Mime-Version: 1.0 X-Scanned-By: MIMEDefang 2.67 on 10.5.11.17 X-detected-operating-system: by monty-python.gnu.org: Genre and OS details not recognized. Cc: Dor Laor , Avi Kivity Subject: [Qemu-devel] [RFC][PATCH v2] suppressing queue notification with queue depth parameter (was: [RFC][PATCH] Queue notify support for virtio block device.) X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org The following patch allows to suppress virtio queue notification with the number of requests passed as parameter. Changes from v1: - code styling, - parameter "x-queue-depth-suppress-notify" for queue depth adjustment. repository: /home/vadimr/work/upstream/qemu branch: master commit d23a1c2fbd23e3da9a671a35c95324d2c630e4c9 Author: Vadim Rozenfeld Date: Thu Jan 14 08:09:26 2010 +0200 [RFC][PATCH v2] suppressing queue notification with queue depth parameter { @@ -2110,6 +2122,7 @@ DriveInfo *drive_init(QemuOpts *opts, void *opaque, const char *devaddr; DriveInfo *dinfo; int snapshot = 0; + int queue_depth = 1; *fatal_error = 1; @@ -2141,6 +2154,7 @@ DriveInfo *drive_init(QemuOpts *opts, void *opaque, file = qemu_opt_get(opts, "file"); serial = qemu_opt_get(opts, "serial"); + queue_depth = qemu_opt_get_number(opts, "x-queue-depth-suppress-notify",1); if ((buf = qemu_opt_get(opts, "if")) != NULL) { pstrcpy(devname, sizeof(devname), buf); @@ -2375,6 +2389,7 @@ DriveInfo *drive_init(QemuOpts *opts, void *opaque, dinfo->on_read_error = on_read_error; dinfo->on_write_error = on_write_error; dinfo->opts = opts; + dinfo->queue_depth = queue_depth; if (serial) strncpy(dinfo->serial, serial, sizeof(serial)); QTAILQ_INSERT_TAIL(&drives, dinfo, next); diff --git a/hw/virtio-blk.c b/hw/virtio-blk.c index cb1ae1f..93b584d 100644 --- a/hw/virtio-blk.c +++ b/hw/virtio-blk.c @@ -28,6 +28,8 @@ typedef struct VirtIOBlock char serial_str[BLOCK_SERIAL_STRLEN + 1]; QEMUBH *bh; size_t config_size; + unsigned int queue_depth; + unsigned int requests; } VirtIOBlock; static VirtIOBlock *to_virtio_blk(VirtIODevice *vdev) @@ -87,6 +89,8 @@ typedef struct VirtIOBlockReq struct VirtIOBlockReq *next; } VirtIOBlockReq; +static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq); + static void virtio_blk_req_complete(VirtIOBlockReq *req, int status) { VirtIOBlock *s = req->dev; @@ -95,6 +99,11 @@ static void virtio_blk_req_complete(VirtIOBlockReq *req, int status) virtqueue_push(s->vq, &req->elem, req->qiov.size + sizeof(*req->in)); virtio_notify(&s->vdev, s->vq); + virtio_blk_handle_output(&s->vdev, s->vq); + if (--s->requests == (s->queue_depth - 1)) { + virtio_queue_set_notification(s->vq, 1); + } + qemu_free(req); } @@ -340,6 +349,10 @@ static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq) exit(1); } + if (++s->requests == s->queue_depth) { + virtio_queue_set_notification(s->vq, 0); + } + req->out = (void *)req->elem.out_sg[0].iov_base; req->in = (void *)req->elem.in_sg[req->elem.in_num - 1].iov_base; @@ -502,6 +515,7 @@ VirtIODevice *virtio_blk_init(DeviceState *dev, DriveInfo *dinfo) s->vdev.reset = virtio_blk_reset; s->bs = dinfo->bdrv; s->rq = NULL; + s->queue_depth = drive_get_queue_depth(dinfo->bdrv); if (strlen(ps)) strncpy(s->serial_str, ps, sizeof(s->serial_str)); else diff --git a/qemu-config.c b/qemu-config.c index c3203c8..6fcf958 100644 --- a/qemu-config.c +++ b/qemu-config.c @@ -78,6 +78,10 @@ QemuOptsList qemu_drive_opts = { },{ .name = "readonly", .type = QEMU_OPT_BOOL, + },{ + .name = "x-queue-depth-suppress-notify", + .type = QEMU_OPT_NUMBER, + .help = "number of requests in queueu before suppressing notify", }, { /* end if list */ } }, diff --git a/sysemu.h b/sysemu.h index 9d80bb2..6eecbe1 100644 --- a/sysemu.h +++ b/sysemu.h @@ -183,6 +183,7 @@ typedef struct DriveInfo { BlockInterfaceErrorAction on_read_error; BlockInterfaceErrorAction on_write_error; char serial[BLOCK_SERIAL_STRLEN + 1]; + int queue_depth; QTAILQ_ENTRY(DriveInfo) next; } DriveInfo; @@ -198,6 +199,7 @@ extern DriveInfo *drive_get_by_id(const char *id); extern int drive_get_max_bus(BlockInterfaceType type); extern void drive_uninit(DriveInfo *dinfo); extern const char *drive_get_serial(BlockDriverState *bdrv); +extern int drive_get_queue_depth(BlockDriverState *bdrv); extern BlockInterfaceErrorAction drive_get_on_error( BlockDriverState *bdrv, int is_read); diff --git a/vl.c b/vl.c index b048e89..517d290 100644 --- a/vl.c +++ b/vl.c @@ -2043,6 +2043,18 @@ const char *drive_get_serial(BlockDriverState *bdrv) return "\0"; } +int drive_get_queue_depth(BlockDriverState *bdrv) +{ + DriveInfo *dinfo; + + QTAILQ_FOREACH(dinfo, &drives, next) { + if (dinfo->bdrv == bdrv) + return dinfo->queue_depth; + } + + return 1; +} + BlockInterfaceErrorAction drive_get_on_error( BlockDriverState *bdrv, int is_read)