From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Fri, 29 Mar 2019 18:37:23 +0100
From: Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH] Convert struct pid count to refcount_t
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To: Joel Fernandes <joel@joelfernandes.org>
Cc: Jann Horn <jannh@google.com>, Kees Cook <keescook@chromium.org>, "Eric W. Biederman" <ebiederm@xmission.com>, LKML <linux-kernel@vger.kernel.org>, Android Kernel Team <kernel-team@android.com>, Kernel Hardening <kernel-hardening@lists.openwall.com>, Andrew Morton <akpm@linux-foundation.org>, Matthew Wilcox <willy@infradead.org>, Michal Hocko <mhocko@suse.com>, "Reshetova, Elena" <elena.reshetova@intel.com>
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On 03/28, Joel Fernandes wrote:
>
> Also Oleg, why not just call refcount_dec_and_test like below?

Of course we can, this is just optimization to avoid the atomic op if possible.

Does this optimization really help? I have no idea ;)

But as you can see, it surely helps to provoke the interesting discussions!

Oleg.