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Date:   Fri, 17 Jun 2022 17:56:43 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Eric Dumazet <edumazet@google.com>
Cc:     Waiman Long <longman@redhat.com>,
        Shakeel Butt <shakeelb@google.com>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        Will Deacon <will@kernel.org>, Roman Penyaev <rpenyaev@suse.de>
Subject: Re: [PATCH] locking/rwlocks: do not starve writers
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On Fri, Jun 17, 2022 at 05:24:58PM +0200, Eric Dumazet wrote:

> If only tasklist_lock is problematic and needs the unfair variant,
> then changing a few read_lock() for tasklist_lock will be less
> invasive than ~1000 read_lock() elsewhere....

This is unknown. tasklist_lock was the obvious one, there might be more.
Lockdep should be able to tell you.