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Date:   Tue, 28 Jun 2022 15:28:26 -0400
From:   "Alex Xu (Hello71)" <alex_y_xu@yahoo.ca>
Subject: Re: CONFIG_ANDROID (was: rcu_sched detected expedited stalls in
 amdgpu after suspend)
To:     paulmck@kernel.org
Cc:     alexander.deucher@amd.com, amd-gfx@lists.freedesktop.org,
        Arve =?iso-8859-1?b?SGr4bm5lduVn?= <arve@android.com>,
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        Hridya Valsaraju <hridya@google.com>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
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        linux-kernel@vger.kernel.org, Martijn Coenen <maco@android.com>,
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Excerpts from Paul E. McKenney's message of June 28, 2022 2:54 pm:
> All you need to do to get the previous behavior is to add something like
> this to your defconfig file:
>=20
> CONFIG_RCU_EXP_CPU_STALL_TIMEOUT=3D21000
>=20
> Any reason why this will not work for you?

As far as I know, I do not require any particular RCU debugging features=20
intended for developers; as an individual user and distro maintainer, I=20
would like to select the option corresponding to "emit errors for=20
unexpected conditions which should be reported upstream", not "emit=20
debugging information for development purposes".

Therefore, I think 0 is a suitable setting for me and most ordinary=20
(not tightly controlled) distributions. My concern is that other users=20
and distro maintainers will also have confusion about what value to set=20
and whether the warnings are important, since the help text does not say=20
anything about Android, and "make oldconfig" does not indicate that the=20
default value is different for Android.

My suggestion is that the default be set to 0, and if a non-zero value=20
is appropriate for Android, that should be communicated to the Android=20
developers, not made conditional on CONFIG_ANDROID.

Thanks,
Alex.