From patchwork Thu May 30 11:28:11 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 10968633 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E30991398 for ; Thu, 30 May 2019 11:28:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D526028B03 for ; Thu, 30 May 2019 11:28:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C8EDC28B0F; Thu, 30 May 2019 11:28:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 619EB28B03 for ; Thu, 30 May 2019 11:28:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726924AbfE3L2X (ORCPT ); Thu, 30 May 2019 07:28:23 -0400 Received: from mail-wr1-f65.google.com ([209.85.221.65]:41562 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726699AbfE3L2R (ORCPT ); Thu, 30 May 2019 07:28:17 -0400 Received: by mail-wr1-f65.google.com with SMTP id c2so3963693wrm.8; Thu, 30 May 2019 04:28:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=0zslCchXkU9/iE2gw3QRd9dcZ6RTFcWD2DAc5YM+PJU=; b=l/k58YGHILVSQ3nCQBqu7l0MU9SYbdSF3ri5oKMWxBw/9EO1UR+Zs57slpEHC4BfJw ZLELcw/QSBiSq7Jh0wbnj3uynynmL864AH/3COtA/u5hTMo3m0lNJWdhlXUhUlzsYoyy fkjjmovfRx2HZJ8Xk3Ouek+ofPuCSXcHfIb1ox3iCCO087iziUEHTXX2t1y/bSb2MFha dmUSImR2uxEoiI/vokVk9xaQIPx8ZMP4uYPpd11XhIDf5MoTREoTv9ZPRiHKk2cbyPBx EkyUW3hAwsXthKIxjPmtJ8VbMilnfy4XcH6/yRs3m5V2pPOgf663vx7HlIPJOvDRqPHs GeCQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=0zslCchXkU9/iE2gw3QRd9dcZ6RTFcWD2DAc5YM+PJU=; b=Dw8e0whjCLHOSxVSyZ3k84OgOjBv8eb9hvPxODmos0CU1FFeobzASrQk0UzZ3fVHOA H4q1uFMc++GrA8ANElCIGzOB2bpjCI6vTdNwj5VJPGgWBvDh4J2aEaYdAecBabMA/Qew bT32jXZubQyjBzKxs6oZZHwpZuIUERI8xOJdARN4Xa3MCZpNPQKRM31COE021/fB0+42 KHXgJuqt8AO84dXNQxnInEmL4tsViX9u0AP3i3V22PpINUYy4h+PdpQdOQLgiS64VjwI jI+Z7gjV85atAw2wlxcu1zXt2ib8qodT7BsaLEG8a7OTUdIbN+kwzA9ZL6n7aREmy5kY TVLQ== X-Gm-Message-State: APjAAAWi+wKfNj6IQI0xzLtZF8kZuQpz5MArUSLRmIngElkwn0fgb024 4794iMGZNsC3mzEGYv1kLp+0wweV X-Google-Smtp-Source: APXvYqwQ1ZolElu//tR8q8fWIFyB08c1e/wWz3z13PLYJQojuLdZFVZt1KGebgNtncrsD4/yItIvJQ== X-Received: by 2002:a5d:6389:: with SMTP id p9mr2330104wru.297.1559215695004; Thu, 30 May 2019 04:28:15 -0700 (PDT) Received: from donizetti.redhat.com ([2001:b07:6468:f312:f91e:ffe0:9205:3b26]) by smtp.gmail.com with ESMTPSA id o14sm2601855wrp.77.2019.05.30.04.28.14 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Thu, 30 May 2019 04:28:14 -0700 (PDT) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: jejb@linux.ibm.com, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, stefanha@redhat.com Subject: [PATCH 2/2] virtio_scsi: implement request batching Date: Thu, 30 May 2019 13:28:11 +0200 Message-Id: <20190530112811.3066-3-pbonzini@redhat.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190530112811.3066-1-pbonzini@redhat.com> References: <20190530112811.3066-1-pbonzini@redhat.com> MIME-Version: 1.0 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Adding the command and kicking the virtqueue so far was done one after another. Make the kick optional, so that we can take into account SCMD_LAST. We also need a commit_rqs callback to kick the device if blk-mq aborts the submission before the last request is reached. Suggested-by: Stefan Hajnoczi Signed-off-by: Paolo Bonzini Reviewed-by: Hannes Reinecke Reviewed-by: Ming Lei --- drivers/scsi/virtio_scsi.c | 55 +++++++++++++++++++++++++++----------- 1 file changed, 40 insertions(+), 15 deletions(-) diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c index 8af01777d09c..918c811cea95 100644 --- a/drivers/scsi/virtio_scsi.c +++ b/drivers/scsi/virtio_scsi.c @@ -375,14 +375,7 @@ static void virtscsi_event_done(struct virtqueue *vq) virtscsi_vq_done(vscsi, &vscsi->event_vq, virtscsi_complete_event); }; -/** - * virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue - * @vq : the struct virtqueue we're talking about - * @cmd : command structure - * @req_size : size of the request buffer - * @resp_size : size of the response buffer - */ -static int virtscsi_add_cmd(struct virtqueue *vq, +static int __virtscsi_add_cmd(struct virtqueue *vq, struct virtio_scsi_cmd *cmd, size_t req_size, size_t resp_size) { @@ -427,17 +420,39 @@ static int virtscsi_add_cmd(struct virtqueue *vq, return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_ATOMIC); } -static int virtscsi_kick_cmd(struct virtio_scsi_vq *vq, +static void virtscsi_kick_vq(struct virtio_scsi_vq *vq) +{ + bool needs_kick; + unsigned long flags; + + spin_lock_irqsave(&vq->vq_lock, flags); + needs_kick = virtqueue_kick_prepare(vq->vq); + spin_unlock_irqrestore(&vq->vq_lock, flags); + + if (needs_kick) + virtqueue_notify(vq->vq); +} + +/** + * virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue, optionally kick it + * @vq : the struct virtqueue we're talking about + * @cmd : command structure + * @req_size : size of the request buffer + * @resp_size : size of the response buffer + * @kick : whether to kick the virtqueue immediately + */ +static int virtscsi_add_cmd(struct virtio_scsi_vq *vq, struct virtio_scsi_cmd *cmd, - size_t req_size, size_t resp_size) + size_t req_size, size_t resp_size, + bool kick) { unsigned long flags; int err; bool needs_kick = false; spin_lock_irqsave(&vq->vq_lock, flags); - err = virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size); - if (!err) + err = __virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size); + if (!err && kick) needs_kick = virtqueue_kick_prepare(vq->vq); spin_unlock_irqrestore(&vq->vq_lock, flags); @@ -502,6 +517,7 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, struct virtio_scsi *vscsi = shost_priv(shost); struct virtio_scsi_vq *req_vq = virtscsi_pick_vq_mq(vscsi, sc); struct virtio_scsi_cmd *cmd = scsi_cmd_priv(sc); + bool kick; unsigned long flags; int req_size; int ret; @@ -531,7 +547,8 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, req_size = sizeof(cmd->req.cmd); } - ret = virtscsi_kick_cmd(req_vq, cmd, req_size, sizeof(cmd->resp.cmd)); + kick = (sc->flags & SCMD_LAST) != 0; + ret = virtscsi_add_cmd(req_vq, cmd, req_size, sizeof(cmd->resp.cmd), kick); if (ret == -EIO) { cmd->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET; spin_lock_irqsave(&req_vq->vq_lock, flags); @@ -549,8 +566,8 @@ static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) int ret = FAILED; cmd->comp = ∁ - if (virtscsi_kick_cmd(&vscsi->ctrl_vq, cmd, - sizeof cmd->req.tmf, sizeof cmd->resp.tmf) < 0) + if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd, + sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0) goto out; wait_for_completion(&comp); @@ -664,6 +681,13 @@ static int virtscsi_map_queues(struct Scsi_Host *shost) return blk_mq_virtio_map_queues(qmap, vscsi->vdev, 2); } +static void virtscsi_commit_rqs(struct Scsi_Host *shost, u16 hwq) +{ + struct virtio_scsi *vscsi = shost_priv(shost); + + virtscsi_kick_vq(&vscsi->req_vqs[hwq]); +} + /* * The host guarantees to respond to each command, although I/O * latencies might be higher than on bare metal. Reset the timer @@ -681,6 +705,7 @@ static struct scsi_host_template virtscsi_host_template = { .this_id = -1, .cmd_size = sizeof(struct virtio_scsi_cmd), .queuecommand = virtscsi_queuecommand, + .commit_rqs = virtscsi_commit_rqs, .change_queue_depth = virtscsi_change_queue_depth, .eh_abort_handler = virtscsi_abort, .eh_device_reset_handler = virtscsi_device_reset,