From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michal =?utf-8?Q?Koutn=C3=BD?= <mkoutny-IBi9RG/b67k@public.gmane.org>
Subject: Re: [PATCH v3 6/8] workingset: memcg: sleep when flushing stats in
 workingset_refault()
Date: Wed, 5 Apr 2023 10:00:47 +0200
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To: Yosry Ahmed <yosryahmed-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>
Cc: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Josef Bacik <josef-DigfWCa+lFGyeJad7bwFQA@public.gmane.org>, Jens Axboe <axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org>, Zefan Li <lizefan.x-EC8Uxl6Npydl57MIdRCFDg@public.gmane.org>, Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>, Michal Hocko <mhocko-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Roman Gushchin <roman.gushchin-fxUVXftIFDnyG1zEObXtfA@public.gmane.org>, Shakeel Butt <shakeelb-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Muchun Song <muchun.song-fxUVXftIFDnyG1zEObXtfA@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Vasily Averin <vasily.averin-fxUVXftIFDnyG1zEObXtfA@public.gmane.org>, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-block-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, bpf-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Michal Hocko <mhocko-IBi9RG/b67k@public.gmane.org>


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On Tue, Apr 04, 2023 at 11:09:02AM -0700, Yosry Ahmed <yosryahmed-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org> wrote:
> IIUC there are multiple places where we can sleep in this path, we can
> sleep waiting for a page to be read from disk, we can sleep during
> allocating the page to read into, and IIUC the allocations on the
> fault path can even run into reclaim, going into the vmscan code. So
> there are precedents, but I am not sure if that's enough argument.

I expect it'd depend on the proportion of the slow/fast paths.
OK, let's see how it turns out in wider population.

Thanks,
Michal

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