From: Muni Sekhar <munisekharrms@gmail.com>
To: Bharath Vedartham <linux.bhar@gmail.com>
Cc: kernelnewbies <kernelnewbies@kernelnewbies.org>
Subject: Re: wait_event()\ wait_event_interruptible()\ wait_event_interruptible_timeout() and wake_up()
Date: Mon, 29 Jul 2019 23:37:34 +0530 [thread overview]
Message-ID: <CAHhAz+gCJ4KrvO87D1gE01cdmdzya22RGZwh3Rz78OtZEn641w@mail.gmail.com> (raw)
In-Reply-To: <20190729180122.GA11403@bharath12345-Inspiron-5559>
On Mon, Jul 29, 2019 at 11:31 PM Bharath Vedartham <linux.bhar@gmail.com> wrote:
>
> On Mon, Jul 29, 2019 at 10:48:57PM +0530, Muni Sekhar wrote:
> > Hi All,
> >
> > Let us assume that multiple processes are waiting on wait_event()\
> > wait_event_interruptible()\ wait_event_interruptible_timeout(), which
> > process gets woken up on calling wake_up()??
> >
> > I presume wake_up() picks one process, but is there any algorithm to
> > pick which process?
> >
> >
> > --
> > Thanks,
> > Sekhar
> Sorry to spoil the fun here. But check out what the queue data structure
> is all about. 'wait_queue' :)
A wait queue is a doubly linked list of wait_queue_t structures that
hold pointers to the process task structures of the processes that are
blocking. Each list is headed up by a wait_queue_head_t structure,
which marks the head of the list and holds the spinlock to the list to
prevent wait_queue_t additional race conditions
>
> Thank you
> Bharath
> > _______________________________________________
> > Kernelnewbies mailing list
> > Kernelnewbies@kernelnewbies.org
> > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
--
Thanks,
Sekhar
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next prev parent reply other threads:[~2019-07-29 18:08 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-29 17:18 wait_event()\ wait_event_interruptible()\ wait_event_interruptible_timeout() and wake_up() Muni Sekhar
2019-07-29 17:28 ` Greg KH
2019-07-29 18:01 ` Bharath Vedartham
2019-07-29 18:07 ` Muni Sekhar [this message]
2019-07-29 18:29 ` Valdis Klētnieks
2019-07-29 18:27 ` Valdis Klētnieks
2019-07-30 1:59 ` Muni Sekhar
2019-08-06 8:45 ` Muni Sekhar
2019-08-06 11:42 ` Valdis Klētnieks
2019-08-06 12:00 ` Muni Sekhar
2019-08-06 12:26 ` Greg KH
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