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Date:   Thu, 30 May 2019 18:13:48 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     David Laight <David.Laight@ACULAB.COM>
Cc:     "'Eric W. Biederman'" <ebiederm@xmission.com>,
        Deepa Dinamani <deepa.kernel@gmail.com>,
        Al Viro <viro@ZenIV.linux.org.uk>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: pselect/etc semantics
Message-ID: <20190530161348.GJ22536@redhat.com>
References: <20190522032144.10995-1-deepa.kernel@gmail.com>
 <20190529161157.GA27659@redhat.com>
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 <9150b8cb8123426492a82e193f45229e@AcuMS.aculab.com>
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On 05/30, David Laight wrote:
>
> 4) As an optimisation a signal that arrives after the timer
>    expires, but before the mask is restored can be 'deemed'
>    to have happened before the timeout expired and EINTR
>    returned.

This is what pselect/ppoll already does.

Oleg.