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Date:   Mon, 27 Sep 2021 09:53:59 -0700
From:   Sultan Alsawaf <sultan@kerneltoast.com>
To:     Michal Hocko <mhocko@suse.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: vmscan: Replace shrinker_rwsem trylocks with SRCU
 protection
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On Mon, Sep 27, 2021 at 10:36:36AM +0200, Michal Hocko wrote:
> Can you be more specific about those scenarios please?

I see frequent tmpfs mounts/unmounts in Android which result in lots of
superblocks being created and destroyed, and each superblock has its own
shrinker.

> I have a vague recollection that this approach has been proposed in the
> past. Have you checked previous attempts?

I wasn't aware that there were previous attempts. Is this [1] the previous
attempt you're thinking of? It seems like the thread just died out. Was the main
gripe that always enabling CONFIG_SRCU increased the kernel's size too much when
tinyfication was desired?

Sultan

[1] https://lore.kernel.org/all/153365347929.19074.12509495712735843805.stgit@localhost.localdomain/