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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 E0B87C4361B for ; Fri, 18 Dec 2020 15:17:58 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 83BED23AFD for ; Fri, 18 Dec 2020 15:17:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 83BED23AFD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49666 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kqHW1-0006tc-E3 for qemu-devel@archiver.kernel.org; Fri, 18 Dec 2020 10:17:57 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:53694) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kqHRT-0001pL-3M for qemu-devel@nongnu.org; Fri, 18 Dec 2020 10:13:15 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:43827) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kqHRR-0005JF-Ed for qemu-devel@nongnu.org; Fri, 18 Dec 2020 10:13:14 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1608304392; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xJiEf52kBwjzkSm42TkiheUWTQr6Ww5uUJ9fkpn4mek=; b=dILsjvNYEHi2s5j7pAmrYlAZB56F35dIK6iYOYg64YoxVfHgYSjKnO4i+uNsYW9sBhVtpz PocbFj0QCxrNQX8jiZsRFv7vG5yYZzriskrAHmhdtLoioFNUOpULyPdE1wOyF3Lh939RcX 1SigPErTz6Eu2MItMKemVegE1JZhsKQ= 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-30-oj5G4S-FObaZt_GVGcXawQ-1; Fri, 18 Dec 2020 10:13:08 -0500 X-MC-Unique: oj5G4S-FObaZt_GVGcXawQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 41A1180362E; Fri, 18 Dec 2020 15:13:06 +0000 (UTC) Received: from localhost (ovpn-114-84.ams2.redhat.com [10.36.114.84]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C14C710013C0; Fri, 18 Dec 2020 15:13:05 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Subject: [PULL 06/30] block/io.c: drop assertion on double waiting for request serialisation Date: Fri, 18 Dec 2020 16:12:25 +0100 Message-Id: <20201218151249.715731-7-mreitz@redhat.com> In-Reply-To: <20201218151249.715731-1-mreitz@redhat.com> References: <20201218151249.715731-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=63.128.21.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action 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: Kevin Wolf , Peter Maydell , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Vladimir Sementsov-Ogievskiy The comments states, that on misaligned request we should have already been waiting. But for bdrv_padding_rmw_read, we called bdrv_mark_request_serialising with align = request_alignment, and now we serialise with align = cluster_size. So we may have to wait again with larger alignment. Note, that the only user of BDRV_REQ_SERIALISING is backup which issues cluster-aligned requests, so seems the assertion should not fire for now. But it's wrong anyway. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Paolo Bonzini Message-Id: <20201021145859.11201-3-vsementsov@virtuozzo.com> Signed-off-by: Max Reitz --- block/io.c | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/block/io.c b/block/io.c index 24205f5168..27370107b2 100644 --- a/block/io.c +++ b/block/io.c @@ -1827,7 +1827,6 @@ bdrv_co_write_req_prepare(BdrvChild *child, int64_t offset, uint64_t bytes, BdrvTrackedRequest *req, int flags) { BlockDriverState *bs = child->bs; - bool waited; int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE); if (bs->read_only) { @@ -1839,15 +1838,7 @@ bdrv_co_write_req_prepare(BdrvChild *child, int64_t offset, uint64_t bytes, assert(!(flags & ~BDRV_REQ_MASK)); if (flags & BDRV_REQ_SERIALISING) { - waited = bdrv_mark_request_serialising(req, bdrv_get_cluster_size(bs)); - /* - * For a misaligned request we should have already waited earlier, - * because we come after bdrv_padding_rmw_read which must be called - * with the request already marked as serialising. - */ - assert(!waited || - (req->offset == req->overlap_offset && - req->bytes == req->overlap_bytes)); + bdrv_mark_request_serialising(req, bdrv_get_cluster_size(bs)); } else { bdrv_wait_serialising_requests(req); } -- 2.29.2