From patchwork Thu Sep 14 14:00:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13385479 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 13D45EEAA40 for ; Thu, 14 Sep 2023 14:03:29 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qgmuq-00080h-6V; Thu, 14 Sep 2023 10:01:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgmuc-0007yZ-Bo for qemu-devel@nongnu.org; Thu, 14 Sep 2023 10:01:44 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgmuV-00019T-LP for qemu-devel@nongnu.org; Thu, 14 Sep 2023 10:01:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694700084; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MAOhD67sgYXgN63nbkZvtAVWc6L847RzatreqXJJcKg=; b=OtvgMg+a2oGF0N8ViVWKlunD/vS5Yj4A3eBBtQDIX4YDtFo68Bw+M2++0hyxjpUFYuZwla oxobt6Bjn8UzvV+WQUbLxwf1tRWC4nsURKbJJHGCNfd322jdPqCyTZkqsPsvCUoiOREN1E SBrtXVUIvhIWozRR38A7SPFIqd8uKhQ= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-369-GnC-y2r4MJKOnvasmPRETg-1; Thu, 14 Sep 2023 10:01:20 -0400 X-MC-Unique: GnC-y2r4MJKOnvasmPRETg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 34EA8857A9A; Thu, 14 Sep 2023 14:01:05 +0000 (UTC) Received: from localhost (unknown [10.39.194.105]) by smtp.corp.redhat.com (Postfix) with ESMTP id AD54E1054FC2; Thu, 14 Sep 2023 14:01:04 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , , Hanna Reitz , "Michael S. Tsirkin" Subject: [PATCH 1/4] block/file-posix: set up Linux AIO and io_uring in the current thread Date: Thu, 14 Sep 2023 10:00:58 -0400 Message-ID: <20230914140101.1065008-2-stefanha@redhat.com> In-Reply-To: <20230914140101.1065008-1-stefanha@redhat.com> References: <20230914140101.1065008-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org The file-posix block driver currently only sets up Linux AIO and io_uring in the BDS's AioContext. In the multi-queue block layer we must be able to submit I/O requests in AioContexts that do not have Linux AIO and io_uring set up yet since any thread can call into the block driver. Set up Linux AIO and io_uring for the current AioContext during request submission. We lose the ability to return an error from .bdrv_file_open() when Linux AIO and io_uring setup fails (e.g. due to resource limits). Instead the user only gets warnings and we fall back to aio=threads. This is still better than a fatal error after startup. Signed-off-by: Stefan Hajnoczi Reviewed-by: Eric Blake --- block/file-posix.c | 99 ++++++++++++++++++++++------------------------ 1 file changed, 47 insertions(+), 52 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index 4757914ac0..e9dbb87c57 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -713,17 +713,11 @@ static int raw_open_common(BlockDriverState *bs, QDict *options, #ifdef CONFIG_LINUX_AIO /* Currently Linux does AIO only for files opened with O_DIRECT */ - if (s->use_linux_aio) { - if (!(s->open_flags & O_DIRECT)) { - error_setg(errp, "aio=native was specified, but it requires " - "cache.direct=on, which was not specified."); - ret = -EINVAL; - goto fail; - } - if (!aio_setup_linux_aio(bdrv_get_aio_context(bs), errp)) { - error_prepend(errp, "Unable to use native AIO: "); - goto fail; - } + if (s->use_linux_aio && !(s->open_flags & O_DIRECT)) { + error_setg(errp, "aio=native was specified, but it requires " + "cache.direct=on, which was not specified."); + ret = -EINVAL; + goto fail; } #else if (s->use_linux_aio) { @@ -734,14 +728,7 @@ static int raw_open_common(BlockDriverState *bs, QDict *options, } #endif /* !defined(CONFIG_LINUX_AIO) */ -#ifdef CONFIG_LINUX_IO_URING - if (s->use_linux_io_uring) { - if (!aio_setup_linux_io_uring(bdrv_get_aio_context(bs), errp)) { - error_prepend(errp, "Unable to use io_uring: "); - goto fail; - } - } -#else +#ifndef CONFIG_LINUX_IO_URING if (s->use_linux_io_uring) { error_setg(errp, "aio=io_uring was specified, but is not supported " "in this build."); @@ -2442,6 +2429,44 @@ static bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov) return true; } +static inline bool raw_check_linux_io_uring(BDRVRawState *s) +{ + Error *local_err = NULL; + AioContext *ctx; + + if (!s->use_linux_io_uring) { + return false; + } + + ctx = qemu_get_current_aio_context(); + if (unlikely(!aio_setup_linux_io_uring(ctx, &local_err))) { + error_reportf_err(local_err, "Unable to use linux io_uring, " + "falling back to thread pool: "); + s->use_linux_io_uring = false; + return false; + } + return true; +} + +static inline bool raw_check_linux_aio(BDRVRawState *s) +{ + Error *local_err = NULL; + AioContext *ctx; + + if (!s->use_linux_aio) { + return false; + } + + ctx = qemu_get_current_aio_context(); + if (unlikely(!aio_setup_linux_aio(ctx, &local_err))) { + error_reportf_err(local_err, "Unable to use Linux AIO, " + "falling back to thread pool: "); + s->use_linux_aio = false; + return false; + } + return true; +} + static int coroutine_fn raw_co_prw(BlockDriverState *bs, uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int type) { @@ -2470,13 +2495,13 @@ static int coroutine_fn raw_co_prw(BlockDriverState *bs, uint64_t offset, if (s->needs_alignment && !bdrv_qiov_is_aligned(bs, qiov)) { type |= QEMU_AIO_MISALIGNED; #ifdef CONFIG_LINUX_IO_URING - } else if (s->use_linux_io_uring) { + } else if (raw_check_linux_io_uring(s)) { assert(qiov->size == bytes); ret = luring_co_submit(bs, s->fd, offset, qiov, type); goto out; #endif #ifdef CONFIG_LINUX_AIO - } else if (s->use_linux_aio) { + } else if (raw_check_linux_aio(s)) { assert(qiov->size == bytes); ret = laio_co_submit(s->fd, offset, qiov, type, s->aio_max_batch); @@ -2566,39 +2591,13 @@ static int coroutine_fn raw_co_flush_to_disk(BlockDriverState *bs) }; #ifdef CONFIG_LINUX_IO_URING - if (s->use_linux_io_uring) { + if (raw_check_linux_io_uring(s)) { return luring_co_submit(bs, s->fd, 0, NULL, QEMU_AIO_FLUSH); } #endif return raw_thread_pool_submit(handle_aiocb_flush, &acb); } -static void raw_aio_attach_aio_context(BlockDriverState *bs, - AioContext *new_context) -{ - BDRVRawState __attribute__((unused)) *s = bs->opaque; -#ifdef CONFIG_LINUX_AIO - if (s->use_linux_aio) { - Error *local_err = NULL; - if (!aio_setup_linux_aio(new_context, &local_err)) { - error_reportf_err(local_err, "Unable to use native AIO, " - "falling back to thread pool: "); - s->use_linux_aio = false; - } - } -#endif -#ifdef CONFIG_LINUX_IO_URING - if (s->use_linux_io_uring) { - Error *local_err = NULL; - if (!aio_setup_linux_io_uring(new_context, &local_err)) { - error_reportf_err(local_err, "Unable to use linux io_uring, " - "falling back to thread pool: "); - s->use_linux_io_uring = false; - } - } -#endif -} - static void raw_close(BlockDriverState *bs) { BDRVRawState *s = bs->opaque; @@ -3897,7 +3896,6 @@ BlockDriver bdrv_file = { .bdrv_co_copy_range_from = raw_co_copy_range_from, .bdrv_co_copy_range_to = raw_co_copy_range_to, .bdrv_refresh_limits = raw_refresh_limits, - .bdrv_attach_aio_context = raw_aio_attach_aio_context, .bdrv_co_truncate = raw_co_truncate, .bdrv_co_getlength = raw_co_getlength, @@ -4267,7 +4265,6 @@ static BlockDriver bdrv_host_device = { .bdrv_co_copy_range_from = raw_co_copy_range_from, .bdrv_co_copy_range_to = raw_co_copy_range_to, .bdrv_refresh_limits = raw_refresh_limits, - .bdrv_attach_aio_context = raw_aio_attach_aio_context, .bdrv_co_truncate = raw_co_truncate, .bdrv_co_getlength = raw_co_getlength, @@ -4403,7 +4400,6 @@ static BlockDriver bdrv_host_cdrom = { .bdrv_co_pwritev = raw_co_pwritev, .bdrv_co_flush_to_disk = raw_co_flush_to_disk, .bdrv_refresh_limits = cdrom_refresh_limits, - .bdrv_attach_aio_context = raw_aio_attach_aio_context, .bdrv_co_truncate = raw_co_truncate, .bdrv_co_getlength = raw_co_getlength, @@ -4529,7 +4525,6 @@ static BlockDriver bdrv_host_cdrom = { .bdrv_co_pwritev = raw_co_pwritev, .bdrv_co_flush_to_disk = raw_co_flush_to_disk, .bdrv_refresh_limits = cdrom_refresh_limits, - .bdrv_attach_aio_context = raw_aio_attach_aio_context, .bdrv_co_truncate = raw_co_truncate, .bdrv_co_getlength = raw_co_getlength, From patchwork Thu Sep 14 14:00:59 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13385478 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 13BAAEEAA46 for ; Thu, 14 Sep 2023 14:02:49 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qgmuV-0007x8-Ie; Thu, 14 Sep 2023 10:01:35 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgmu9-0007qG-B4 for qemu-devel@nongnu.org; Thu, 14 Sep 2023 10:01:16 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgmu7-00016D-Pb for qemu-devel@nongnu.org; Thu, 14 Sep 2023 10:01:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694700070; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+EW5i/CXHPkV539q/Tucf8Yr3W4QFWyx9CktEylXY7c=; b=En79K4VxMVlqQ9YJgbfDMEiLe4gOFr7erq3NfvB5xCsPnjUNx+L8thSsrIgwdoMMW0TSvH +MiRcBNk+X/qBOwnFhSKE1TYFjZyhAnF7xlQzzOluzu8pjT8X22Cn77HyGWLNQaNJdc79A 7edjFTO1khGxvCZVfUwRsMQQnHbta6A= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-691-R_MECfEePD-P1AdGHMebhA-1; Thu, 14 Sep 2023 10:01:07 -0400 X-MC-Unique: R_MECfEePD-P1AdGHMebhA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 40CFC18312C0; Thu, 14 Sep 2023 14:01:07 +0000 (UTC) Received: from localhost (unknown [10.39.194.105]) by smtp.corp.redhat.com (Postfix) with ESMTP id BEA26200A35C; Thu, 14 Sep 2023 14:01:06 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , , Hanna Reitz , "Michael S. Tsirkin" Subject: [PATCH 2/4] virtio-blk: add lock to protect s->rq Date: Thu, 14 Sep 2023 10:00:59 -0400 Message-ID: <20230914140101.1065008-3-stefanha@redhat.com> In-Reply-To: <20230914140101.1065008-1-stefanha@redhat.com> References: <20230914140101.1065008-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org s->rq is accessed from IO_CODE and GLOBAL_STATE_CODE. Introduce a lock to protect s->rq and eliminate reliance on the AioContext lock. Signed-off-by: Stefan Hajnoczi Reviewed-by: Eric Blake --- include/hw/virtio/virtio-blk.h | 3 +- hw/block/virtio-blk.c | 67 +++++++++++++++++++++++----------- 2 files changed, 47 insertions(+), 23 deletions(-) diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h index dafec432ce..9881009c22 100644 --- a/include/hw/virtio/virtio-blk.h +++ b/include/hw/virtio/virtio-blk.h @@ -54,7 +54,8 @@ struct VirtIOBlockReq; struct VirtIOBlock { VirtIODevice parent_obj; BlockBackend *blk; - void *rq; + QemuMutex rq_lock; + void *rq; /* protected by rq_lock */ VirtIOBlkConf conf; unsigned short sector_mask; bool original_wce; diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index a1f8e15522..ee38e089bc 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -82,8 +82,11 @@ static int virtio_blk_handle_rw_error(VirtIOBlockReq *req, int error, /* Break the link as the next request is going to be parsed from the * ring again. Otherwise we may end up doing a double completion! */ req->mr_next = NULL; - req->next = s->rq; - s->rq = req; + + WITH_QEMU_LOCK_GUARD(&s->rq_lock) { + req->next = s->rq; + s->rq = req; + } } else if (action == BLOCK_ERROR_ACTION_REPORT) { virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); if (acct_failed) { @@ -1183,10 +1186,13 @@ static void virtio_blk_dma_restart_bh(void *opaque) { VirtIOBlock *s = opaque; - VirtIOBlockReq *req = s->rq; + VirtIOBlockReq *req; MultiReqBuffer mrb = {}; - s->rq = NULL; + WITH_QEMU_LOCK_GUARD(&s->rq_lock) { + req = s->rq; + s->rq = NULL; + } aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); while (req) { @@ -1238,22 +1244,29 @@ static void virtio_blk_reset(VirtIODevice *vdev) AioContext *ctx; VirtIOBlockReq *req; + /* Dataplane has stopped... */ + assert(!s->dataplane_started); + + /* ...but requests may still be in flight. */ ctx = blk_get_aio_context(s->blk); aio_context_acquire(ctx); blk_drain(s->blk); + aio_context_release(ctx); /* We drop queued requests after blk_drain() because blk_drain() itself can * produce them. */ - while (s->rq) { - req = s->rq; - s->rq = req->next; - virtqueue_detach_element(req->vq, &req->elem, 0); - virtio_blk_free_request(req); + WITH_QEMU_LOCK_GUARD(&s->rq_lock) { + while (s->rq) { + req = s->rq; + s->rq = req->next; + + /* No other threads can access req->vq here */ + virtqueue_detach_element(req->vq, &req->elem, 0); + + virtio_blk_free_request(req); + } } - aio_context_release(ctx); - - assert(!s->dataplane_started); blk_set_enable_write_cache(s->blk, s->original_wce); } @@ -1443,18 +1456,22 @@ static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status) static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f) { VirtIOBlock *s = VIRTIO_BLK(vdev); - VirtIOBlockReq *req = s->rq; - while (req) { - qemu_put_sbyte(f, 1); + WITH_QEMU_LOCK_GUARD(&s->rq_lock) { + VirtIOBlockReq *req = s->rq; - if (s->conf.num_queues > 1) { - qemu_put_be32(f, virtio_get_queue_index(req->vq)); + while (req) { + qemu_put_sbyte(f, 1); + + if (s->conf.num_queues > 1) { + qemu_put_be32(f, virtio_get_queue_index(req->vq)); + } + + qemu_put_virtqueue_element(vdev, f, &req->elem); + req = req->next; } - - qemu_put_virtqueue_element(vdev, f, &req->elem); - req = req->next; } + qemu_put_sbyte(f, 0); } @@ -1480,8 +1497,11 @@ static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f, req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq)); virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req); - req->next = s->rq; - s->rq = req; + + WITH_QEMU_LOCK_GUARD(&s->rq_lock) { + req->next = s->rq; + s->rq = req; + } } return 0; @@ -1628,6 +1648,8 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) s->host_features); virtio_init(vdev, VIRTIO_ID_BLOCK, s->config_size); + qemu_mutex_init(&s->rq_lock); + s->blk = conf->conf.blk; s->rq = NULL; s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1; @@ -1679,6 +1701,7 @@ static void virtio_blk_device_unrealize(DeviceState *dev) virtio_del_queue(vdev, i); } qemu_coroutine_dec_pool_size(conf->num_queues * conf->queue_size / 2); + qemu_mutex_destroy(&s->rq_lock); blk_ram_registrar_destroy(&s->blk_ram_registrar); qemu_del_vm_change_state_handler(s->change); blockdev_mark_auto_del(s->blk); From patchwork Thu Sep 14 14:01:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13385480 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id CA82CEEAA45 for ; Thu, 14 Sep 2023 14:03:31 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qgmuP-0007vf-Up; Thu, 14 Sep 2023 10:01:30 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgmuB-0007qT-Dc for qemu-devel@nongnu.org; Thu, 14 Sep 2023 10:01:18 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgmu9-00016S-Lk for qemu-devel@nongnu.org; Thu, 14 Sep 2023 10:01:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694700073; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=86KzCOvFJg2LMFfuLkPAliW+kHglL9eVmg7cS+AqMcE=; b=aWWC8CbYr/LJ4qP7qP1+relXQc2E7p90uVRuQNbQnbh09R8BYsz9hgl5oTOALSsXvVTMxa eP+tA8GUjDyhk4rMRDjFF31/FrMeTE54k0OD9Q3+awQ87tQOYWAPZdeKP8zXcLfMCIv+oo L+ZWl6Zoo/eEW9gXYVYVz10xycND/Xs= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-189-D0DmRMC_Ozud6bEfO53eZw-1; Thu, 14 Sep 2023 10:01:09 -0400 X-MC-Unique: D0DmRMC_Ozud6bEfO53eZw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 10CE788B7A2; Thu, 14 Sep 2023 14:01:09 +0000 (UTC) Received: from localhost (unknown [10.39.194.105]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8F1EE1054FC1; Thu, 14 Sep 2023 14:01:08 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , , Hanna Reitz , "Michael S. Tsirkin" Subject: [PATCH 3/4] virtio-blk: don't lock AioContext in the completion code path Date: Thu, 14 Sep 2023 10:01:00 -0400 Message-ID: <20230914140101.1065008-4-stefanha@redhat.com> In-Reply-To: <20230914140101.1065008-1-stefanha@redhat.com> References: <20230914140101.1065008-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@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=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Nothing in the completion code path relies on the AioContext lock anymore. Virtqueues are only accessed from one thread at any moment and the s->rq global state is protected by its own lock now. Signed-off-by: Stefan Hajnoczi Reviewed-by: Eric Blake --- hw/block/virtio-blk.c | 34 ++++------------------------------ 1 file changed, 4 insertions(+), 30 deletions(-) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index ee38e089bc..f5315df042 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -105,7 +105,6 @@ static void virtio_blk_rw_complete(void *opaque, int ret) VirtIOBlock *s = next->dev; VirtIODevice *vdev = VIRTIO_DEVICE(s); - aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); while (next) { VirtIOBlockReq *req = next; next = req->mr_next; @@ -138,7 +137,6 @@ static void virtio_blk_rw_complete(void *opaque, int ret) block_acct_done(blk_get_stats(s->blk), &req->acct); virtio_blk_free_request(req); } - aio_context_release(blk_get_aio_context(s->conf.conf.blk)); } static void virtio_blk_flush_complete(void *opaque, int ret) @@ -146,19 +144,13 @@ static void virtio_blk_flush_complete(void *opaque, int ret) VirtIOBlockReq *req = opaque; VirtIOBlock *s = req->dev; - aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); - if (ret) { - if (virtio_blk_handle_rw_error(req, -ret, 0, true)) { - goto out; - } + if (ret && virtio_blk_handle_rw_error(req, -ret, 0, true)) { + return; } virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); block_acct_done(blk_get_stats(s->blk), &req->acct); virtio_blk_free_request(req); - -out: - aio_context_release(blk_get_aio_context(s->conf.conf.blk)); } static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret) @@ -168,11 +160,8 @@ static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret) bool is_write_zeroes = (virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type) & ~VIRTIO_BLK_T_BARRIER) == VIRTIO_BLK_T_WRITE_ZEROES; - aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); - if (ret) { - if (virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) { - goto out; - } + if (ret && virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) { + return; } virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); @@ -180,9 +169,6 @@ static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret) block_acct_done(blk_get_stats(s->blk), &req->acct); } virtio_blk_free_request(req); - -out: - aio_context_release(blk_get_aio_context(s->conf.conf.blk)); } #ifdef __linux__ @@ -229,10 +215,8 @@ static void virtio_blk_ioctl_complete(void *opaque, int status) virtio_stl_p(vdev, &scsi->data_len, hdr->dxfer_len); out: - aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); virtio_blk_req_complete(req, status); virtio_blk_free_request(req); - aio_context_release(blk_get_aio_context(s->conf.conf.blk)); g_free(ioctl_req); } @@ -672,7 +656,6 @@ static void virtio_blk_zone_report_complete(void *opaque, int ret) { ZoneCmdData *data = opaque; VirtIOBlockReq *req = data->req; - VirtIOBlock *s = req->dev; VirtIODevice *vdev = VIRTIO_DEVICE(req->dev); struct iovec *in_iov = data->in_iov; unsigned in_num = data->in_num; @@ -763,10 +746,8 @@ static void virtio_blk_zone_report_complete(void *opaque, int ret) } out: - aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); virtio_blk_req_complete(req, err_status); virtio_blk_free_request(req); - aio_context_release(blk_get_aio_context(s->conf.conf.blk)); g_free(data->zone_report_data.zones); g_free(data); } @@ -829,10 +810,8 @@ static void virtio_blk_zone_mgmt_complete(void *opaque, int ret) err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD; } - aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); virtio_blk_req_complete(req, err_status); virtio_blk_free_request(req); - aio_context_release(blk_get_aio_context(s->conf.conf.blk)); } static int virtio_blk_handle_zone_mgmt(VirtIOBlockReq *req, BlockZoneOp op) @@ -882,7 +861,6 @@ static void virtio_blk_zone_append_complete(void *opaque, int ret) { ZoneCmdData *data = opaque; VirtIOBlockReq *req = data->req; - VirtIOBlock *s = req->dev; VirtIODevice *vdev = VIRTIO_DEVICE(req->dev); int64_t append_sector, n; uint8_t err_status = VIRTIO_BLK_S_OK; @@ -905,10 +883,8 @@ static void virtio_blk_zone_append_complete(void *opaque, int ret) trace_virtio_blk_zone_append_complete(vdev, req, append_sector, ret); out: - aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); virtio_blk_req_complete(req, err_status); virtio_blk_free_request(req); - aio_context_release(blk_get_aio_context(s->conf.conf.blk)); g_free(data); } @@ -944,10 +920,8 @@ static int virtio_blk_handle_zone_append(VirtIOBlockReq *req, return 0; out: - aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); virtio_blk_req_complete(req, err_status); virtio_blk_free_request(req); - aio_context_release(blk_get_aio_context(s->conf.conf.blk)); return err_status; } From patchwork Thu Sep 14 14:01:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13385476 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 0F594EEAA44 for ; Thu, 14 Sep 2023 14:02:49 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qgmuo-00080X-Uy; Thu, 14 Sep 2023 10:01:54 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgmuH-0007tw-5n for qemu-devel@nongnu.org; Thu, 14 Sep 2023 10:01:22 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgmuB-00016t-RQ for qemu-devel@nongnu.org; Thu, 14 Sep 2023 10:01:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694700075; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ggWYSS4tCysLcdQD+okbR5l6Rp8lQ+134dpLIuJ4Qkw=; b=KWoNIEY3nForrqARPSawXvXZR8Xkzl7Qxut5DJrLWqSfh082FP1CMA5pklWhJg8btZ9YOS ZkqEPSYCtFbUHOnzluKdMc7/xezSiCNEgiHBHWzK3hnBg1Ju1tLHwQA6JBKnspbKQjY+DW kAPNuclH3S320rzNiYHxaOhnOfhxAH8= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-50-XQ3CJS9ZMSuYPN9I8yTznA-1; Thu, 14 Sep 2023 10:01:11 -0400 X-MC-Unique: XQ3CJS9ZMSuYPN9I8yTznA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E98B788B7AC; Thu, 14 Sep 2023 14:01:10 +0000 (UTC) Received: from localhost (unknown [10.39.194.105]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6D7359A; Thu, 14 Sep 2023 14:01:10 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , , Hanna Reitz , "Michael S. Tsirkin" Subject: [PATCH 4/4] virtio-blk: don't lock AioContext in the submission code path Date: Thu, 14 Sep 2023 10:01:01 -0400 Message-ID: <20230914140101.1065008-5-stefanha@redhat.com> In-Reply-To: <20230914140101.1065008-1-stefanha@redhat.com> References: <20230914140101.1065008-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@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_H3=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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org There is no need to acquire the AioContext lock around blk_aio_*() or blk_get_geometry() anymore. I/O plugging (defer_call()) also does not require the AioContext lock anymore. Signed-off-by: Stefan Hajnoczi Reviewed-by: Eric Blake --- hw/block/virtio-blk.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index f5315df042..e110f9718b 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -1111,7 +1111,6 @@ void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq) MultiReqBuffer mrb = {}; bool suppress_notifications = virtio_queue_get_notification(vq); - aio_context_acquire(blk_get_aio_context(s->blk)); defer_call_begin(); do { @@ -1137,7 +1136,6 @@ void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq) } defer_call_end(); - aio_context_release(blk_get_aio_context(s->blk)); } static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq) @@ -1168,7 +1166,6 @@ static void virtio_blk_dma_restart_bh(void *opaque) s->rq = NULL; } - aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); while (req) { VirtIOBlockReq *next = req->next; if (virtio_blk_handle_request(req, &mrb)) { @@ -1192,8 +1189,6 @@ static void virtio_blk_dma_restart_bh(void *opaque) /* Paired with inc in virtio_blk_dma_restart_cb() */ blk_dec_in_flight(s->conf.conf.blk); - - aio_context_release(blk_get_aio_context(s->conf.conf.blk)); } static void virtio_blk_dma_restart_cb(void *opaque, bool running,