From: Tejun Heo tj@kernel.org
mainline inclusion from mainline-v5.13-rc1 commit f46ec84b5acbf8d7067d71a6bbdde213d4b86036 category: bugfix bugzilla: 187443, https://gitee.com/openeuler/kernel/issues/I5PFPV CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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ioc_adjust_base_vrate() ignored vrate_min when rq_wait_pct indicates that there is QD contention. The reasoning was that QD depletion always reliably indicates device saturation and thus it's safe to override user specified vrate_min. However, this sometimes leads to unnecessary throttling, especially on really fast devices, because vrate adjustments have delays and inertia. It also confuses users because the behavior violates the explicitly specified configuration.
This patch drops the special case handling so that vrate_min is always applied.
Signed-off-by: Tejun Heo tj@kernel.org Link: https://lore.kernel.org/r/YIIo1HuyNmhDeiNx@slm.duckdns.org Signed-off-by: Jens Axboe axboe@kernel.dk
confilict: block/blk-iocost.c
Signed-off-by: Li Nan linan122@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- block/blk-iocost.c | 4 ---- 1 file changed, 4 deletions(-)
diff --git a/block/blk-iocost.c b/block/blk-iocost.c index fb8f959a7f32..08e4ba856e3b 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -2341,10 +2341,6 @@ static void ioc_timer_fn(struct timer_list *timer) u64 vrate = ioc->vtime_base_rate; u64 vrate_min = ioc->vrate_min, vrate_max = ioc->vrate_max;
- /* rq_wait signal is always reliable, ignore user vrate_min */ - if (rq_wait_pct > RQ_WAIT_BUSY_PCT) - vrate_min = VRATE_MIN; - /* * If vrate is out of bounds, apply clamp gradually as the * bounds can change abruptly. Otherwise, apply busy_level