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Date:   Fri, 21 Aug 2020 00:45:24 +0300
From:   Cyrill Gorcunov <gorcunov@gmail.com>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        criu@openvz.org, bpf@vger.kernel.org,
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Subject: Re: [PATCH 04/17] kcmp: In kcmp_epoll_target use fget_task
Message-ID: <20200820214524.GS2074@grain>
References: <87ft8l6ic3.fsf@x220.int.ebiederm.org>
 <20200817220425.9389-4-ebiederm@xmission.com>
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On Mon, Aug 17, 2020 at 05:04:12PM -0500, Eric W. Biederman wrote:
> Use the helper fget_task and simplify the code.
> 
> As well as simplifying the code this removes one unnecessary increment of
> struct files_struct.  This unnecessary increment of files_struct.count can
> result in exec unnecessarily unsharing files_struct and breaking posix
> locks, and it can result in fget_light having to fallback to fget reducing
> performance.
> 
> Suggested-by: Oleg Nesterov <oleg@redhat.com>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>

I really like this simplification!