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From: Andrey Konovalov <andreyknvl@gmail.com>
Date: Tue, 9 Jan 2024 04:27:48 +0100
Message-ID: <CA+fCnZdjF=8bchUs1RNA2e+8HSZTkOw6Tkz0Ye6Znh=zdf8yrA@mail.gmail.com>
Subject: Re: [PATCH 11/15] stackdepot: use read/write lock
To: Marco Elver <elver@google.com>
Cc: andrey.konovalov@linux.dev, Alexander Potapenko <glider@google.com>, 
	Dmitry Vyukov <dvyukov@google.com>, Vlastimil Babka <vbabka@suse.cz>, kasan-dev@googlegroups.com, 
	Evgenii Stepanov <eugenis@google.com>, Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org, 
	linux-kernel@vger.kernel.org, Andrey Konovalov <andreyknvl@google.com>
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On Tue, Jan 2, 2024 at 1:59=E2=80=AFPM Marco Elver <elver@google.com> wrote=
:
>
> > I started looking into using percpu-rwsem, but it appears that it
> > doesn't have the irqsave/irqrestore API flavor. I suspect that it
> > shouldn't be hard to add it, but I'd rather not pursue this as a part
> > of this series.
> >
> > So I still propose to keep the rwlock for now, and switch to
> > percpu-rwsem later together with the other perf changes.
>
> I may have gotten lost in the post-vacation email avalanche and missed
> it: did you already send the percpu-rwsem optimization? I am a little
> worried about the contention the plain rwlock introduces on big
> machines.

I didn't get to working on that part unfortunately :(

I filed https://bugzilla.kernel.org/show_bug.cgi?id=3D218312 for this.