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From: Tejun Heo <tj@kernel.org>
To: "boy.wu" <boy.wu@mediatek.com>
Cc: Josef Bacik <josef@toxicpanda.com>, Jens Axboe <axboe@kernel.dk>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	AngeloGioacchino Del Regno
	<angelogioacchino.delregno@collabora.com>,
	Boris Burkov <boris@bur.io>,
	cgroups@vger.kernel.org, linux-block@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-mediatek@lists.infradead.org, iverlin.wang@mediatek.com
Subject: Re: [PATCH] blk-cgroup: add spin_lock for u64_stats_update
Date: Fri, 5 Jul 2024 07:13:30 -1000	[thread overview]
Message-ID: <Zogpum23mjHZC8yO@slm.duckdns.org> (raw)
In-Reply-To: <20240705075544.11315-1-boy.wu@mediatek.com>

Hello,

On Fri, Jul 05, 2024 at 03:55:44PM +0800, boy.wu wrote:
> From: Boy Wu <boy.wu@mediatek.com>
> 
> In 32bit SMP systems, if the system is stressed on the sys node
> by processes, it may cause blkcg_fill_root_iostats to have a concurrent

What is sys node?

> problem on the seqlock in u64_stats_update, which will cause a deadlock 
> on u64_stats_fetch_begin in blkcg_print_one_stat.

I'm not following the scenario. Can you please detail the scenario where
this leads to deadlocks?

Thanks.

-- 
tejun

  parent reply	other threads:[~2024-07-05 17:13 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-07-05  7:55 [PATCH] blk-cgroup: add spin_lock for u64_stats_update boy.wu
2024-07-05 17:05 ` Markus Elfring
2024-07-08  2:52   ` Boy Wu (吳勃誼)
2024-07-08  5:43     ` Markus Elfring
2024-07-10  6:19       ` Boy Wu (吳勃誼)
2024-07-05 17:13 ` Tejun Heo [this message]
2024-07-08  2:00   ` [PATCH] " Boy Wu (吳勃誼)
2024-07-08 18:36     ` tj

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