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=-18.8 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,USER_AGENT_GIT autolearn=unavailable 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 E2AF0C4332D for ; Tue, 2 Mar 2021 06:41:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B4BAD6148E for ; Tue, 2 Mar 2021 06:41:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1573912AbhCBD2R (ORCPT ); Mon, 1 Mar 2021 22:28:17 -0500 Received: from mail.kernel.org ([198.145.29.99]:51350 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236783AbhCAUdo (ORCPT ); Mon, 1 Mar 2021 15:33:44 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3FB2C65104; Mon, 1 Mar 2021 18:09:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614622172; bh=oP76Qz3NljqfPRGvR0YglTT+F7RxoB8GYhz+DtHEjAw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qOwQzIWUiMOm4F7RG1e73K2jwwmhU7tdCCxuyQZwBXHEyShEtbHI8081Z1rI31/oK AcnbBrB6BZ8bdWgwlI7fY9+9SKAm9jOKSowQKYrrBN1DwVG5P2NnXfiOmzLh91GYY/ Yc2qxxl03DFIovEW8USdq1lpTbMaxe8AIX9tRKCk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mikulas Patocka , "J. Bruce Fields" , Mike Snitzer Subject: [PATCH 5.11 757/775] dm writecache: fix performance degradation in ssd mode Date: Mon, 1 Mar 2021 17:15:25 +0100 Message-Id: <20210301161238.722034854@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161201.679371205@linuxfoundation.org> References: <20210301161201.679371205@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mikulas Patocka commit cb728484a7710c202f02b96aa0962ce9b07aa5c2 upstream. Fix a thinko in ssd_commit_superblock. region.count is in sectors, not bytes. This bug doesn't corrupt data, but it causes performance degradation. Signed-off-by: Mikulas Patocka Fixes: dc8a01ae1dbd ("dm writecache: optimize superblock write") Cc: stable@vger.kernel.org # v5.7+ Reported-by: J. Bruce Fields Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-writecache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -523,7 +523,7 @@ static void ssd_commit_superblock(struct region.bdev = wc->ssd_dev->bdev; region.sector = 0; - region.count = PAGE_SIZE; + region.count = PAGE_SIZE >> SECTOR_SHIFT; if (unlikely(region.sector + region.count > wc->metadata_sectors)) region.count = wc->metadata_sectors - region.sector;