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Tue, 7 Apr 2020 06:41:41 +0000 Subject: Re: [PATCH for-5.0 v2 2/3] block: Increase BB.in_flight for coroutine interfaces To: Kevin Wolf , qemu-block@nongnu.org References: <20200406171403.6761-1-kwolf@redhat.com> <20200406171403.6761-3-kwolf@redhat.com> From: Vladimir Sementsov-Ogievskiy X-Tagtoolbar-Keys: D20200407094132107 Message-ID: <9d0aa9cc-61a1-fd14-357e-6fb0ba2742dd@virtuozzo.com> Date: Tue, 7 Apr 2020 09:41:32 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 In-Reply-To: <20200406171403.6761-3-kwolf@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: AM6P195CA0017.EURP195.PROD.OUTLOOK.COM (2603:10a6:209:81::30) To AM7PR08MB5494.eurprd08.prod.outlook.com (2603:10a6:20b:dc::15) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [192.168.100.2] (185.215.60.160) by AM6P195CA0017.EURP195.PROD.OUTLOOK.COM (2603:10a6:209:81::30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2878.16 via Frontend Transport; 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BlockDriverState *bs; + blk_inc_in_flight(blk); blk_wait_while_drained(blk); /* Call blk_bs() only after waiting, the graph may have changed */ @@ -1175,6 +1176,7 @@ int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset, ret = bdrv_co_preadv(blk->root, offset, bytes, qiov, flags); bdrv_dec_in_flight(bs); + blk_dec_in_flight(blk); return ret; } @@ -1337,7 +1339,6 @@ static void blk_aio_complete(BlkAioEmAIOCB *acb) { if (acb->has_returned) { acb->common.cb(acb->common.opaque, acb->rwco.ret); - blk_dec_in_flight(acb->rwco.blk); qemu_aio_unref(acb); } } @@ -1357,7 +1358,6 @@ static BlockAIOCB *blk_aio_prwv(BlockBackend *blk, int64_t offset, int bytes, BlkAioEmAIOCB *acb; Coroutine *co; - blk_inc_in_flight(blk); acb = blk_aio_get(&blk_aio_em_aiocb_info, blk, cb, opaque); acb->rwco = (BlkRwCo) { .blk = blk, @@ -1388,9 +1388,7 @@ static void blk_aio_read_entry(void *opaque) QEMUIOVector *qiov = rwco->iobuf; if (rwco->blk->quiesce_counter) { - blk_dec_in_flight(rwco->blk); blk_wait_while_drained(rwco->blk); - blk_inc_in_flight(rwco->blk); } assert(qiov->size == acb->bytes); (and same for write, ioctl, flush, discard). It seems more consistent.. Should it work? -- Best regards, Vladimir