From patchwork Thu Jan 30 21:30:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 11358763 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 996BD139A for ; Thu, 30 Jan 2020 21:35:14 +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 6D84120674 for ; Thu, 30 Jan 2020 21:35:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Jmiftbca" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D84120674 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:39354 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ixHSz-0003sO-Fd for patchwork-qemu-devel@patchwork.kernel.org; Thu, 30 Jan 2020 16:35:13 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:55866) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ixHPV-0006lE-W4 for qemu-devel@nongnu.org; Thu, 30 Jan 2020 16:31:39 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ixHPU-0004pz-Jw for qemu-devel@nongnu.org; Thu, 30 Jan 2020 16:31:37 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:38449 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ixHPU-0004mR-G0 for qemu-devel@nongnu.org; Thu, 30 Jan 2020 16:31:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580419893; 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=rCXifKAz8zdxy0qXQ36bHA8fkm12N4h0f95Q6RTvdGc=; b=JmiftbcaTWO+bqn1t+yiUMOCuTj+0ByRsvQLoBHpH67R5kQSTtsgb5GxisG1UIXjge6noA qCP8hsR5HimqJSWVexZ6Uohh+wzB67/ONWg8nphFxMWFrce8ObPGv/Cd/V9SpFF4/0YDzx UQcCRWnZTmB0KHaamAgSLt55M6Ow6lA= 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-29-Gh2ATA1DMfCbOoPsok2cJA-1; Thu, 30 Jan 2020 16:31:31 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B425610054E3; Thu, 30 Jan 2020 21:31:29 +0000 (UTC) Received: from localhost (unknown [10.36.118.87]) by smtp.corp.redhat.com (Postfix) with ESMTP id 498CC84BCE; Thu, 30 Jan 2020 21:31:29 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [PULL 02/18] block/io: wait for serialising requests when a request becomes serialising Date: Thu, 30 Jan 2020 21:30:58 +0000 Message-Id: <20200130213114.325157-3-stefanha@redhat.com> In-Reply-To: <20200130213114.325157-1-stefanha@redhat.com> References: <20200130213114.325157-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: Gh2ATA1DMfCbOoPsok2cJA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.81 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-block@nongnu.org, Julia Suvorova , Markus Armbruster , Max Reitz , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Aarushi Mehta Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Paolo Bonzini Marking without waiting would not result in actual serialising behavior. Thus, make a call bdrv_mark_request_serialising sufficient for serialisation to happen. Signed-off-by: Paolo Bonzini Message-id: 1578495356-46219-3-git-send-email-pbonzini@redhat.com Message-Id: <1578495356-46219-3-git-send-email-pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi --- block/file-posix.c | 1 - block/io.c | 40 +++++++++++++++++---------------------- include/block/block_int.h | 3 +-- 3 files changed, 18 insertions(+), 26 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index 1b805bd938..2b08b02d27 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -2753,7 +2753,6 @@ raw_do_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int bytes, req->overlap_bytes = req->bytes; bdrv_mark_request_serialising(req, bs->bl.request_alignment); - bdrv_wait_serialising_requests(req); } #endif diff --git a/block/io.c b/block/io.c index b3a67fe1db..c466df8ed5 100644 --- a/block/io.c +++ b/block/io.c @@ -41,6 +41,7 @@ #define MAX_BOUNCE_BUFFER (32768 << BDRV_SECTOR_BITS) static void bdrv_parent_cb_resize(BlockDriverState *bs); +static bool coroutine_fn bdrv_wait_serialising_requests(BdrvTrackedRequest *self); static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int bytes, BdrvRequestFlags flags); @@ -715,7 +716,7 @@ static void tracked_request_begin(BdrvTrackedRequest *req, qemu_co_mutex_unlock(&bs->reqs_lock); } -void bdrv_mark_request_serialising(BdrvTrackedRequest *req, uint64_t align) +bool bdrv_mark_request_serialising(BdrvTrackedRequest *req, uint64_t align) { int64_t overlap_offset = req->offset & ~(align - 1); uint64_t overlap_bytes = ROUND_UP(req->offset + req->bytes, align) @@ -728,18 +729,7 @@ void bdrv_mark_request_serialising(BdrvTrackedRequest *req, uint64_t align) req->overlap_offset = MIN(req->overlap_offset, overlap_offset); req->overlap_bytes = MAX(req->overlap_bytes, overlap_bytes); -} - -static bool is_request_serialising_and_aligned(BdrvTrackedRequest *req) -{ - /* - * If the request is serialising, overlap_offset and overlap_bytes are set, - * so we can check if the request is aligned. Otherwise, don't care and - * return false. - */ - - return req->serialising && (req->offset == req->overlap_offset) && - (req->bytes == req->overlap_bytes); + return bdrv_wait_serialising_requests(req); } /** @@ -823,7 +813,7 @@ void bdrv_dec_in_flight(BlockDriverState *bs) bdrv_wakeup(bs); } -bool coroutine_fn bdrv_wait_serialising_requests(BdrvTrackedRequest *self) +static bool coroutine_fn bdrv_wait_serialising_requests(BdrvTrackedRequest *self) { BlockDriverState *bs = self->bs; BdrvTrackedRequest *req; @@ -1455,10 +1445,10 @@ static int coroutine_fn bdrv_aligned_preadv(BdrvChild *child, * it ensures that the CoR read and write operations are atomic and * guest writes cannot interleave between them. */ bdrv_mark_request_serialising(req, bdrv_get_cluster_size(bs)); + } else { + bdrv_wait_serialising_requests(req); } - bdrv_wait_serialising_requests(req); - if (flags & BDRV_REQ_COPY_ON_READ) { int64_t pnum; @@ -1851,13 +1841,19 @@ bdrv_co_write_req_prepare(BdrvChild *child, int64_t offset, uint64_t bytes, assert(!(flags & ~BDRV_REQ_MASK)); if (flags & BDRV_REQ_SERIALISING) { - bdrv_mark_request_serialising(req, bdrv_get_cluster_size(bs)); + 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)); + } else { + bdrv_wait_serialising_requests(req); } - waited = bdrv_wait_serialising_requests(req); - - assert(!waited || !req->serialising || - is_request_serialising_and_aligned(req)); assert(req->overlap_offset <= offset); assert(offset + bytes <= req->overlap_offset + req->overlap_bytes); assert(end_sector <= bs->total_sectors || child->perm & BLK_PERM_RESIZE); @@ -2019,7 +2015,6 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BdrvChild *child, padding = bdrv_init_padding(bs, offset, bytes, &pad); if (padding) { bdrv_mark_request_serialising(req, align); - bdrv_wait_serialising_requests(req); bdrv_padding_rmw_read(child, req, &pad, true); @@ -2122,7 +2117,6 @@ int coroutine_fn bdrv_co_pwritev_part(BdrvChild *child, if (bdrv_pad_request(bs, &qiov, &qiov_offset, &offset, &bytes, &pad)) { bdrv_mark_request_serialising(&req, align); - bdrv_wait_serialising_requests(&req); bdrv_padding_rmw_read(child, &req, &pad, false); } diff --git a/include/block/block_int.h b/include/block/block_int.h index dd033d0b37..640fb82c78 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -999,8 +999,7 @@ extern unsigned int bdrv_drain_all_count; void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent); void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent); -bool coroutine_fn bdrv_wait_serialising_requests(BdrvTrackedRequest *self); -void bdrv_mark_request_serialising(BdrvTrackedRequest *req, uint64_t align); +bool coroutine_fn bdrv_mark_request_serialising(BdrvTrackedRequest *req, uint64_t align); BdrvTrackedRequest *coroutine_fn bdrv_co_get_self_request(BlockDriverState *bs); int get_tmp_filename(char *filename, int size);