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Date: Sun, 8 Jul 2007 15:16:25 +0400
From: Oleg Nesterov <oleg@tv-sign.ru>
To: "Robert P. J. Day" <rpjday@mindspring.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>, linux-kernel@vger.kernel.org
Subject: Re: schedule_timeout() called with state TASK_RUNNING from fs/select.c
Message-ID: <20070708111625.GA180@tv-sign.ru>
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Robert P. J. Day wrote:
>
>  as i understand it, schedule_timeout() should always be called with
> a current->state of TASK_INTERRUPTIBLE or TASK_UNINTERRUPTIBLE, no?

No.

Yes, it is pointless to call schedule() if it is known that ->state ==
TASK_RUNNING, but sometimes the task doesn't know its state when it
calls schedule/schedule_timeout, the state could be changed by
try_to_wake_up().

See wait_event_timeout() as an example.

Oleg.