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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 13A70C3F2D8 for ; Mon, 2 Mar 2020 10:07:02 +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 DC4212086A for ; Mon, 2 Mar 2020 10:07:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DC4212086A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=virtuozzo.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57844 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j8hyW-0006Rl-UI for qemu-devel@archiver.kernel.org; Mon, 02 Mar 2020 05:07:00 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:50789) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j8hxV-0004WT-NW for qemu-devel@nongnu.org; Mon, 02 Mar 2020 05:05:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j8hxU-0007lq-Ji for qemu-devel@nongnu.org; Mon, 02 Mar 2020 05:05:57 -0500 Received: from relay.sw.ru ([185.231.240.75]:48184) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j8hxR-0007jH-ST; Mon, 02 Mar 2020 05:05:54 -0500 Received: from vovaso.qa.sw.ru ([10.94.3.0] helo=kvm.qa.sw.ru) by relay.sw.ru with esmtp (Exim 4.92.3) (envelope-from ) id 1j8hxI-000350-Gj; Mon, 02 Mar 2020 13:05:44 +0300 From: Vladimir Sementsov-Ogievskiy To: qemu-block@nongnu.org Subject: [PATCH 5/5] block/io: auto-no-fallback for write-zeroes Date: Mon, 2 Mar 2020 13:05:37 +0300 Message-Id: <20200302100537.29058-6-vsementsov@virtuozzo.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20200302100537.29058-1-vsementsov@virtuozzo.com> References: <20200302100537.29058-1-vsementsov@virtuozzo.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 185.231.240.75 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: fam@euphon.net, kwolf@redhat.com, vsementsov@virtuozzo.com, qemu-devel@nongnu.org, mreitz@redhat.com, stefanha@redhat.com, den@openvz.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" NBD driver may has max_pwrite_zeroes but doesn't has max_pwrite_zeroes_no_fallback limit. This means, that (when BDRV_REQ_NO_FALLBACK is supported) it is beneficial to try send request with BDRV_REQ_NO_FALLBACK instead of splitting the request accordingly to max_pwrite_zeroes. If failed, fallback to old behavior. Signed-off-by: Vladimir Sementsov-Ogievskiy --- block/io.c | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-) diff --git a/block/io.c b/block/io.c index c64566b4cf..48d71b0883 100644 --- a/block/io.c +++ b/block/io.c @@ -1752,17 +1752,28 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, int head = 0; int tail = 0; - int max_write_zeroes = MIN_NON_ZERO((flags & BDRV_REQ_NO_FALLBACK) ? - bs->bl.max_pwrite_zeroes_no_fallback : - bs->bl.max_pwrite_zeroes, INT_MAX); + int max_write_zeroes; int alignment = MAX(bs->bl.pwrite_zeroes_alignment, bs->bl.request_alignment); int max_transfer = MIN_NON_ZERO(bs->bl.max_transfer, MAX_BOUNCE_BUFFER); + bool auto_no_fallback; if (!drv) { return -ENOMEDIUM; } + if (!(flags & BDRV_REQ_NO_FALLBACK) && + (bs->supported_zero_flags & BDRV_REQ_NO_FALLBACK) && + bs->bl.max_pwrite_zeroes && + bs->bl.max_pwrite_zeroes < bytes && + (bs->bl.max_pwrite_zeroes < bs->bl.max_pwrite_zeroes_no_fallback || + bs->bl.max_pwrite_zeroes_no_fallback == 0)) + { + assert(drv->bdrv_co_pwrite_zeroes); + flags |= BDRV_REQ_NO_FALLBACK; + auto_no_fallback = true; + } + if ((flags & ~bs->supported_zero_flags) & BDRV_REQ_NO_FALLBACK) { return -ENOTSUP; } @@ -1770,7 +1781,11 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, assert(alignment % bs->bl.request_alignment == 0); head = offset % alignment; tail = (offset + bytes) % alignment; - max_write_zeroes = QEMU_ALIGN_DOWN(max_write_zeroes, alignment); + max_write_zeroes = + QEMU_ALIGN_DOWN(MIN_NON_ZERO((flags & BDRV_REQ_NO_FALLBACK) ? + bs->bl.max_pwrite_zeroes_no_fallback : + bs->bl.max_pwrite_zeroes, INT_MAX), + alignment); assert(max_write_zeroes >= bs->bl.request_alignment); while (bytes > 0 && !ret) { @@ -1801,6 +1816,13 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, if (drv->bdrv_co_pwrite_zeroes) { ret = drv->bdrv_co_pwrite_zeroes(bs, offset, num, flags & bs->supported_zero_flags); + if (ret == -ENOTSUP && auto_no_fallback) { + flags &= ~BDRV_REQ_NO_FALLBACK; + max_write_zeroes = + QEMU_ALIGN_DOWN(MIN_NON_ZERO(bs->bl.max_pwrite_zeroes, + INT_MAX), alignment); + continue; + } if (ret != -ENOTSUP && (flags & BDRV_REQ_FUA) && !(bs->supported_zero_flags & BDRV_REQ_FUA)) { need_flush = true; -- 2.21.0