From nobody Fri Apr 4 06:28:10 2025 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=nongnu.org ARC-Seal: i=1; a=rsa-sha256; t=1741442301; cv=none; d=zohomail.com; s=zohoarc; b=Y2KCFbsN0PfRq15aACuJjXy4dcbH7YJaYyymoeoKA/CMzGcdn/wEzjnNiEcJBhouR1qhtqHYCyj3UC35NqeuCUW3kJmI0j2ABBIZYs4AB2bSgIgUnW9WsEydxSh3XW0pEBE4Y7QRdSd5RUxAkO2NO4QXbdnjXJUOjkFQH4Puybw= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1741442301; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Reply-To:Reply-To:References:Sender:Subject:Subject:To:To:Message-Id; bh=LEqOrPWMs68iFWnEL8kLp7ux2NOAI0bJNTIIi5TIJlQ=; b=EPef9/+J1mMRxoO5OvTiZ/H2bJHweFBzgC5vyaIxmOkMWQW+8UW0zJGPAv/OYd9RkaGEjnZkChjhAv4mi9w8w+cA42n9Smvnkvl8SATm0Tjdy+huRG29ToWgtBQ7HxXAaAWXLV1Cs7qXlgP4S97XKtxzHaF4oVBKmYRq354lYzo= ARC-Authentication-Results: i=1; mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1741442301861768.6382547993638; Sat, 8 Mar 2025 05:58:21 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tqugF-0004Mk-H4; Sat, 08 Mar 2025 08:57:36 -0500 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 1tqrEv-0006sg-9F; Sat, 08 Mar 2025 05:17:05 -0500 Received: from szxga08-in.huawei.com ([45.249.212.255]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tqrEr-00005s-Br; Sat, 08 Mar 2025 05:17:04 -0500 Received: from mail.maildlp.com (unknown [172.19.88.194]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Z8zTY5SsZz1cyTb; Sat, 8 Mar 2025 18:11:45 +0800 (CST) Received: from kwepemk500007.china.huawei.com (unknown [7.202.194.92]) by mail.maildlp.com (Postfix) with ESMTPS id C50FA140380; Sat, 8 Mar 2025 18:16:43 +0800 (CST) Received: from huawei.com (10.246.99.19) by kwepemk500007.china.huawei.com (7.202.194.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Sat, 8 Mar 2025 18:16:42 +0800 To: , , , , , CC: , , , , , , , , , , , Subject: [PATCH 1/2] io/block: Refactoring the bdrv_drained_begin() function and implement a timeout mechanism. Date: Sat, 8 Mar 2025 18:16:17 +0800 Message-ID: <20250308101618.721954-2-zoudongjie@huawei.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20250308101618.721954-1-zoudongjie@huawei.com> References: <20250308101618.721954-1-zoudongjie@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.246.99.19] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemk500007.china.huawei.com (7.202.194.92) Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=45.249.212.255; envelope-from=zoudongjie@huawei.com; helo=szxga08-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-Mailman-Approved-At: Sat, 08 Mar 2025 08:57:19 -0500 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: , Reply-to: zoudongjie From: zoudongjie via Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZM-MESSAGEID: 1741442304955019000 Content-Type: text/plain; charset="utf-8" From: Zhu Yangyang The bdrv_drained_begin() function is a blocking function. In scenarios wher= e network storage is used and network links fail, it may block for a long time. Therefore, we add a timeout parameter to control the duration of the block. Since bdrv_drained_begin() has been widely adopted, both bdrv_drained_begin= () and bdrv_drained_begin_timeout() will be retained. Signed-off-by: Zhu Yangyang --- block/io.c | 55 ++++++++++++++++++++++++++++++------- include/block/aio-wait.h | 58 ++++++++++++++++++++++++++++++++++++++++ include/block/block-io.h | 7 +++++ util/aio-wait.c | 7 +++++ 4 files changed, 117 insertions(+), 10 deletions(-) diff --git a/block/io.c b/block/io.c index d369b994df..03b8b2dca7 100644 --- a/block/io.c +++ b/block/io.c @@ -255,6 +255,8 @@ typedef struct { bool begin; bool poll; BdrvChild *parent; + int ret; + int64_t timeout; } BdrvCoDrainData; =20 /* Returns true if BDRV_POLL_WHILE() should go into a blocking aio_poll() = */ @@ -283,6 +285,8 @@ static bool bdrv_drain_poll_top_level(BlockDriverState = *bs, return bdrv_drain_poll(bs, ignore_parent, false); } =20 +static int bdrv_do_drained_begin_timeout(BlockDriverState *bs, + BdrvChild *parent, bool poll, int64_t timeout); static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, bool poll); static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent); @@ -296,7 +300,8 @@ static void bdrv_co_drain_bh_cb(void *opaque) if (bs) { bdrv_dec_in_flight(bs); if (data->begin) { - bdrv_do_drained_begin(bs, data->parent, data->poll); + data->ret =3D bdrv_do_drained_begin_timeout( + bs, data->parent, data->poll, data->timeout); } else { assert(!data->poll); bdrv_do_drained_end(bs, data->parent); @@ -310,10 +315,11 @@ static void bdrv_co_drain_bh_cb(void *opaque) aio_co_wake(co); } =20 -static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, - bool begin, - BdrvChild *parent, - bool poll) +static int coroutine_fn bdrv_co_yield_to_drain_timeout(BlockDriverState *b= s, + bool begin, + BdrvChild *parent, + bool poll, + int64_t timeout) { BdrvCoDrainData data; Coroutine *self =3D qemu_coroutine_self(); @@ -329,6 +335,8 @@ static void coroutine_fn bdrv_co_yield_to_drain(BlockDr= iverState *bs, .begin =3D begin, .parent =3D parent, .poll =3D poll, + .timeout =3D timeout, + .ret =3D 0 }; =20 if (bs) { @@ -342,16 +350,25 @@ static void coroutine_fn bdrv_co_yield_to_drain(Block= DriverState *bs, /* If we are resumed from some other event (such as an aio completion = or a * timer callback), it is a bug in the caller that should be fixed. */ assert(data.done); + return data.ret; } =20 -static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, - bool poll) +static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, + bool begin, + BdrvChild *parent, + bool poll) +{ + bdrv_co_yield_to_drain_timeout(bs, begin, parent, poll, -1); +} + +static int bdrv_do_drained_begin_timeout(BlockDriverState *bs, + BdrvChild *parent, bool poll, int64_t timeout_ms) { IO_OR_GS_CODE(); =20 if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(bs, true, parent, poll); - return; + return bdrv_co_yield_to_drain_timeout(bs, true, parent, poll, + timeout_ms); } =20 GLOBAL_STATE_CODE(); @@ -375,8 +392,20 @@ static void bdrv_do_drained_begin(BlockDriverState *bs= , BdrvChild *parent, * nodes. */ if (poll) { - BDRV_POLL_WHILE(bs, bdrv_drain_poll_top_level(bs, parent)); + if (timeout_ms < 0) { + BDRV_POLL_WHILE(bs, bdrv_drain_poll_top_level(bs, parent)); + } else { + return BDRV_POLL_WHILE_TIMEOUT( + bs, bdrv_drain_poll_top_level(bs, parent), timeout_ms); + } } + return 0; +} + +static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, + bool poll) +{ + bdrv_do_drained_begin_timeout(bs, parent, poll, -1); } =20 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, BdrvChild *parent) @@ -390,6 +419,12 @@ bdrv_drained_begin(BlockDriverState *bs) IO_OR_GS_CODE(); bdrv_do_drained_begin(bs, NULL, true); } +int coroutine_mixed_fn +bdrv_drained_begin_timeout(BlockDriverState *bs, int64_t timeout_ms) +{ + IO_OR_GS_CODE(); + return bdrv_do_drained_begin_timeout(bs, NULL, true, timeout_ms); +} =20 /** * This function does not poll, nor must any of its recursively called diff --git a/include/block/aio-wait.h b/include/block/aio-wait.h index cf5e8bde1c..efbcb9777a 100644 --- a/include/block/aio-wait.h +++ b/include/block/aio-wait.h @@ -28,6 +28,8 @@ #include "block/aio.h" #include "qemu/main-loop.h" =20 +#define AIO_WAIT_INTERVAL 10 /* ms */ + /** * AioWait: * @@ -56,6 +58,11 @@ typedef struct { unsigned num_waiters; } AioWait; =20 +typedef struct { + struct QEMUTimer *timer; + int64_t interval; +} AioWaitTimer; + extern AioWait global_aio_wait; =20 /** @@ -99,6 +106,55 @@ extern AioWait global_aio_wait; qatomic_dec(&wait_->num_waiters); \ waited_; }) =20 +/** + * AIO_WAIT_WHILE_TIMEOUT: + * + * Refer to the implementation of AIO_WAIT_WHILE_INTERNAL, + * the timeout parameter is added. + */ +#define AIO_WAIT_WHILE_TIMEOUT(ctx, cond, timeout) ({ \ + int ret_ =3D 0; = \ + AioWait *wait_ =3D &global_aio_wait; = \ + AioContext *ctx_ =3D (ctx); = \ + int64_t start_ =3D qemu_clock_get_ms(QEMU_CLOCK_REALTIME); = \ + int64_t deadline_ =3D start_ + (timeout); = \ + /* Ensure that the aio_poll exits periodically to check timeout. */ \ + AioWaitTimer *s_ =3D g_malloc0(sizeof(AioWaitTimer)); = \ + s_->interval =3D AIO_WAIT_INTERVAL; = \ + /* Increment wait_->num_waiters before evaluating cond. */ \ + qatomic_inc(&wait_->num_waiters); \ + /* Paired with smp_mb in aio_wait_kick(). */ \ + smp_mb__after_rmw(); \ + if (ctx_ && in_aio_context_home_thread(ctx_)) { \ + s_->timer =3D aio_timer_new(ctx_, QEMU_CLOCK_REALTIME, = \ + SCALE_MS, aio_wait_timer_retry, s_); \ + aio_wait_timer_retry(s_); \ + while ((cond)) { \ + aio_poll(ctx_, true); \ + if (qemu_clock_get_ms(QEMU_CLOCK_REALTIME) > deadline_) { \ + ret_ =3D -ETIMEDOUT; = \ + break; \ + } \ + } \ + } else { \ + s_->timer =3D aio_timer_new(qemu_get_aio_context(), = \ + QEMU_CLOCK_REALTIME, SCALE_MS, aio_wait_timer_retry, s_); \ + aio_wait_timer_retry(s_); \ + while ((cond)) { \ + assert(qemu_get_current_aio_context() =3D=3D = \ + qemu_get_aio_context()); \ + aio_poll(qemu_get_aio_context(), true); \ + if (qemu_clock_get_ms(QEMU_CLOCK_REALTIME) > deadline_) { \ + ret_ =3D -ETIMEDOUT; = \ + break; \ + } \ + } \ + } \ + qatomic_dec(&wait_->num_waiters); \ + timer_free(s_->timer); \ + g_free(s_); \ + ret_; }) + #define AIO_WAIT_WHILE(ctx, cond) \ AIO_WAIT_WHILE_INTERNAL(ctx, cond) =20 @@ -149,4 +205,6 @@ static inline bool in_aio_context_home_thread(AioContex= t *ctx) } } =20 +void aio_wait_timer_retry(void *opaque); + #endif /* QEMU_AIO_WAIT_H */ diff --git a/include/block/block-io.h b/include/block/block-io.h index b49e0537dd..84f92d2b09 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -354,6 +354,11 @@ bdrv_co_copy_range(BdrvChild *src, int64_t src_offset, AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \ cond); }) =20 +#define BDRV_POLL_WHILE_TIMEOUT(bs, cond, timeout) ({ \ + BlockDriverState *bs_ =3D (bs); \ + AIO_WAIT_WHILE_TIMEOUT(bdrv_get_aio_context(bs_), \ + cond, timeout); }) + void bdrv_drain(BlockDriverState *bs); =20 int co_wrapper_mixed_bdrv_rdlock @@ -431,6 +436,8 @@ bdrv_drain_poll(BlockDriverState *bs, BdrvChild *ignore= _parent, */ void bdrv_drained_begin(BlockDriverState *bs); =20 +int bdrv_drained_begin_timeout(BlockDriverState *bs, int64_t timeout_ms); + /** * bdrv_do_drained_begin_quiesce: * diff --git a/util/aio-wait.c b/util/aio-wait.c index b5336cf5fd..9aed165529 100644 --- a/util/aio-wait.c +++ b/util/aio-wait.c @@ -84,3 +84,10 @@ void aio_wait_bh_oneshot(AioContext *ctx, QEMUBHFunc *cb= , void *opaque) aio_bh_schedule_oneshot(ctx, aio_wait_bh, &data); AIO_WAIT_WHILE_UNLOCKED(NULL, !data.done); } + +void aio_wait_timer_retry(void *opaque) +{ + AioWaitTimer *s =3D opaque; + + timer_mod(s->timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + s->interv= al); +} --=20 2.33.0