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=-15.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 B55CAC433E0 for ; Mon, 18 Jan 2021 00:52:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8EE4B2250F for ; Mon, 18 Jan 2021 00:52:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730288AbhARAwl (ORCPT ); Sun, 17 Jan 2021 19:52:41 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:36805 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728042AbhARAwM (ORCPT ); Sun, 17 Jan 2021 19:52:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610931046; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lPxOXpRZEK8+IoExIpG2BMHmyj4cl+h7wOpVuwGrBn8=; b=ZlqMouaT53SBhaTL3l9ezHraet70FIAQtkM+3BSvbiJYYqkrB6ulawhNwo/RuCauohM18q md0d50fT8RgxFvIazfuG5dTDvTY9/v3yviS/1pfzCuL2S03yeBuiQ57/jq2vRATIZ2ykDn UypUsl/cXq7sb09jBWDaDcO6dfNMgMw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-577-3MLxtRWzPGSKtHIXp-e0JQ-1; Sun, 17 Jan 2021 19:50:42 -0500 X-MC-Unique: 3MLxtRWzPGSKtHIXp-e0JQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B61D2800D55; Mon, 18 Jan 2021 00:50:40 +0000 (UTC) Received: from localhost (ovpn-12-73.pek2.redhat.com [10.72.12.73]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0D7C15D9CC; Mon, 18 Jan 2021 00:50:36 +0000 (UTC) From: Ming Lei To: Jens Axboe , linux-block@vger.kernel.org, "Martin K . Petersen" , linux-scsi@vger.kernel.org Cc: Ming Lei , Omar Sandoval , Kashyap Desai , Sumanesh Samanta , "Ewan D . Milne" , Hannes Reinecke Subject: [PATCH V6 12/13] scsi: make sure sdev->queue_depth is <= max(shost->can_queue, 1024) Date: Mon, 18 Jan 2021 08:49:20 +0800 Message-Id: <20210118004921.202545-13-ming.lei@redhat.com> In-Reply-To: <20210118004921.202545-1-ming.lei@redhat.com> References: <20210118004921.202545-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Limit scsi device's queue depth is less than max(host->can_queue, 1024) in scsi_change_queue_depth(), and 1024 is big enough for saturating current fast SCSI LUN(SSD, or raid volume on multiple SSDs). Also single hw queue depth is usually enough for saturating single LUN because per-core performance is often considered in storage design. We need this patch for replacing sdev->device_busy with sbitmap which has to be pre-allocated with reasonable max depth. Cc: Omar Sandoval Cc: Kashyap Desai Cc: Sumanesh Samanta Cc: Ewan D. Milne Tested-by: Sumanesh Samanta Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei --- drivers/scsi/scsi.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index 24619c3bebd5..a28d48c850cf 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -214,6 +214,15 @@ void scsi_finish_command(struct scsi_cmnd *cmd) scsi_io_completion(cmd, good_bytes); } + +/* + * 1024 is big enough for saturating the fast scsi LUN now + */ +static int scsi_device_max_queue_depth(struct scsi_device *sdev) +{ + return max_t(int, sdev->host->can_queue, 1024); +} + /** * scsi_change_queue_depth - change a device's queue depth * @sdev: SCSI Device in question @@ -223,6 +232,8 @@ void scsi_finish_command(struct scsi_cmnd *cmd) */ int scsi_change_queue_depth(struct scsi_device *sdev, int depth) { + depth = min_t(int, depth, scsi_device_max_queue_depth(sdev)); + if (depth > 0) { sdev->queue_depth = depth; wmb(); -- 2.28.0