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Thu, 9 Oct 2025 11:15:21 +0000 (GMT) Message-ID: Date: Thu, 9 Oct 2025 16:45:19 +0530 Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [patch v2 2/7] blk-mq-sched: unify elevators checking for async requests To: Yu Kuai , axboe@kernel.dk, bvanassche@acm.org, ming.lei@redhat.com, jmoyer@redhat.com Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yi.zhang@huawei.com, yangerkun@huawei.com, johnny.chenyi@huawei.com References: <20251009074634.527661-1-yukuai1@huaweicloud.com> <20251009074634.527661-3-yukuai1@huaweicloud.com> Content-Language: en-US From: Nilay Shroff In-Reply-To: <20251009074634.527661-3-yukuai1@huaweicloud.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: TYg84TneXMJdH4uTVDTvY6q1MsHUjDVe X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMDA4MDEyMSBTYWx0ZWRfXzg5KbgVmLQkS eq+a6ssalK/zPGT/VM09qGBArW7Ev1klN1/6lh8ODsqWgNNWFNKEqfewj/vXu3E6cXZklspueio duScgkxozdwJhSILj6hhnQ3XAb2VjyI/m16xzK0DR6yafhxcqM8xIbeXITOeQ6vPpsjqXcAmWLK wBYtIMUkVttlOMmeR9Z00+czHpTq67KP1KsZWkIibmXpvycayNbHH8satiC78ClQ51YJBWIr8jr 5rO6zkjvuMR+jp1SoVh6COCpPCodtmS+9bMEVQvIG/IoWbw5yUnDSxdfbpK/zaUdCwuSXFFGE+H QE6YR0VT/nZFcIMdZefIJsCuVEHw5m5TMTBC+bub37+DNKnYuDv0rss/JmxYsgbrxGRmLpYbtQh sbTeu5SvXKevZ+ofb14+LPJztYlaDw== X-Authority-Analysis: v=2.4 cv=cKntc1eN c=1 sm=1 tr=0 ts=68e7994e cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=IkcTkHD0fZMA:10 a=x6icFKpwvdMA:10 a=i0EeH86SAAAA:8 a=VnNF1IyMAAAA:8 a=wiJGR1NNRVUR7wOXJQEA:9 a=QEXdDO2ut3YA:10 a=zgiPjhLxNE0A:10 a=cPQSjfK2_nFv0Q5t_7PE:22 X-Proofpoint-GUID: TYg84TneXMJdH4uTVDTvY6q1MsHUjDVe X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1117,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-10-09_03,2025-10-06_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1011 impostorscore=0 adultscore=0 lowpriorityscore=0 malwarescore=0 suspectscore=0 bulkscore=0 phishscore=0 spamscore=0 priorityscore=1501 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2510020000 definitions=main-2510080121 On 10/9/25 1:16 PM, Yu Kuai wrote: > From: Yu Kuai > > bfq and mq-deadline consider sync writes as async requests and only > resver tags for sync reads by async_depth, however, kyber doesn't > consider sync writes as async requests for now. > > Consider the case there are lots of dirty pages, and user use fsync to > flush dirty pages. In this case sched_tags can be exhausted by sync writes > and sync reads can stuck waiting for tag. Hence let kyber follow what > mq-deadline and bfq did, and unify async requests checking for all > elevators. > > Signed-off-by: Yu Kuai Looks good to me: Reviewed-by: Nilay Shroff