From patchwork Fri May 26 20:22:06 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 767560 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3wZJ4w2mSTz9s7h for ; Sat, 27 May 2017 06:43:44 +1000 (AEST) Received: from localhost ([::1]:38390 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dEM5F-0003LH-Vz for incoming@patchwork.ozlabs.org; Fri, 26 May 2017 16:43:42 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59126) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dELm2-0005yv-NI for qemu-devel@nongnu.org; Fri, 26 May 2017 16:23:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dELm1-0005ZM-H5 for qemu-devel@nongnu.org; Fri, 26 May 2017 16:23:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58458) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dELlr-0005Wr-DM; Fri, 26 May 2017 16:23:39 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 61E6037EEB; Fri, 26 May 2017 20:23:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 61E6037EEB Authentication-Results: ext-mx05.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx05.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=kwolf@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 61E6037EEB Received: from noname.redhat.com (ovpn-116-43.ams2.redhat.com [10.36.116.43]) by smtp.corp.redhat.com (Postfix) with ESMTP id 03976176C6; Fri, 26 May 2017 20:23:33 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Fri, 26 May 2017 22:22:06 +0200 Message-Id: <1495830130-30611-26-git-send-email-kwolf@redhat.com> In-Reply-To: <1495830130-30611-1-git-send-email-kwolf@redhat.com> References: <1495830130-30611-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Fri, 26 May 2017 20:23:38 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH 25/29] qed: Implement .bdrv_co_readv/writev X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, pbonzini@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com, mreitz@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Most of the qed code is now synchronous and matches the coroutine model. One notable exception is the serialisation between requests which can still schedule a callback. Before we can replace this with coroutine locks, let's convert the driver's external interfaces to the coroutine versions. We need to be careful to handle both requests that call the completion callback directly from the calling coroutine (i.e. fully synchronous code) and requests that involve some callback, so that we need to yield and wait for the completion callback coming from outside the coroutine. Signed-off-by: Kevin Wolf --- block/qed.c | 94 +++++++++++++++++++++++++------------------------------------ 1 file changed, 39 insertions(+), 55 deletions(-) diff --git a/block/qed.c b/block/qed.c index 6a83df2..29c3dc5 100644 --- a/block/qed.c +++ b/block/qed.c @@ -1326,16 +1326,31 @@ static void qed_aio_next_io(QEDAIOCB *acb) } } -static BlockAIOCB *qed_aio_setup(BlockDriverState *bs, - int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockCompletionFunc *cb, - void *opaque, int flags) +typedef struct QEDRequestCo { + Coroutine *co; + bool done; + int ret; +} QEDRequestCo; + +static void coroutine_fn qed_co_request_cb(void *opaque, int ret) +{ + QEDRequestCo *co = opaque; + + co->done = true; + co->ret = ret; + qemu_coroutine_enter_if_inactive(co->co); +} + +static int qed_co_request(BlockDriverState *bs, int64_t sector_num, + QEMUIOVector *qiov, int nb_sectors, int flags) { - QEDAIOCB *acb = qemu_aio_get(&qed_aiocb_info, bs, cb, opaque); + QEDRequestCo co = { + .co = qemu_coroutine_self(), + .done = false, + }; + QEDAIOCB *acb = qemu_aio_get(&qed_aiocb_info, bs, qed_co_request_cb, &co); - trace_qed_aio_setup(bs->opaque, acb, sector_num, nb_sectors, - opaque, flags); + trace_qed_aio_setup(bs->opaque, acb, sector_num, nb_sectors, &co, flags); acb->flags = flags; acb->qiov = qiov; @@ -1348,43 +1363,24 @@ static BlockAIOCB *qed_aio_setup(BlockDriverState *bs, /* Start request */ qed_aio_start_io(acb); - return &acb->common; -} -static BlockAIOCB *bdrv_qed_aio_readv(BlockDriverState *bs, - int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockCompletionFunc *cb, - void *opaque) -{ - return qed_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); + if (!co.done) { + qemu_coroutine_yield(); + } + + return co.ret; } -static BlockAIOCB *bdrv_qed_aio_writev(BlockDriverState *bs, - int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockCompletionFunc *cb, - void *opaque) +static int bdrv_qed_co_readv(BlockDriverState *bs, int64_t sector_num, + int nb_sectors, QEMUIOVector *qiov) { - return qed_aio_setup(bs, sector_num, qiov, nb_sectors, cb, - opaque, QED_AIOCB_WRITE); + return qed_co_request(bs, sector_num, qiov, nb_sectors, 0); } -typedef struct { - Coroutine *co; - int ret; - bool done; -} QEDWriteZeroesCB; - -static void coroutine_fn qed_co_pwrite_zeroes_cb(void *opaque, int ret) +static int bdrv_qed_co_writev(BlockDriverState *bs, int64_t sector_num, + int nb_sectors, QEMUIOVector *qiov) { - QEDWriteZeroesCB *cb = opaque; - - cb->done = true; - cb->ret = ret; - if (cb->co) { - aio_co_wake(cb->co); - } + return qed_co_request(bs, sector_num, qiov, nb_sectors, QED_AIOCB_WRITE); } static int coroutine_fn bdrv_qed_co_pwrite_zeroes(BlockDriverState *bs, @@ -1392,9 +1388,7 @@ static int coroutine_fn bdrv_qed_co_pwrite_zeroes(BlockDriverState *bs, int count, BdrvRequestFlags flags) { - BlockAIOCB *blockacb; BDRVQEDState *s = bs->opaque; - QEDWriteZeroesCB cb = { .done = false }; QEMUIOVector qiov; struct iovec iov; @@ -1411,19 +1405,9 @@ static int coroutine_fn bdrv_qed_co_pwrite_zeroes(BlockDriverState *bs, iov.iov_len = count; qemu_iovec_init_external(&qiov, &iov, 1); - blockacb = qed_aio_setup(bs, offset >> BDRV_SECTOR_BITS, &qiov, - count >> BDRV_SECTOR_BITS, - qed_co_pwrite_zeroes_cb, &cb, - QED_AIOCB_WRITE | QED_AIOCB_ZERO); - if (!blockacb) { - return -EIO; - } - if (!cb.done) { - cb.co = qemu_coroutine_self(); - qemu_coroutine_yield(); - } - assert(cb.done); - return cb.ret; + return qed_co_request(bs, offset >> BDRV_SECTOR_BITS, &qiov, + count >> BDRV_SECTOR_BITS, + QED_AIOCB_WRITE | QED_AIOCB_ZERO); } static int bdrv_qed_truncate(BlockDriverState *bs, int64_t offset, Error **errp) @@ -1619,8 +1603,8 @@ static BlockDriver bdrv_qed = { .bdrv_create = bdrv_qed_create, .bdrv_has_zero_init = bdrv_has_zero_init_1, .bdrv_co_get_block_status = bdrv_qed_co_get_block_status, - .bdrv_aio_readv = bdrv_qed_aio_readv, - .bdrv_aio_writev = bdrv_qed_aio_writev, + .bdrv_co_readv = bdrv_qed_co_readv, + .bdrv_co_writev = bdrv_qed_co_writev, .bdrv_co_pwrite_zeroes = bdrv_qed_co_pwrite_zeroes, .bdrv_truncate = bdrv_qed_truncate, .bdrv_getlength = bdrv_qed_getlength,