lkml.org 
[lkml]   [2007]   [Mar]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRE: Clarification required about select vs wake_up race condition
    Date
    From
    Hi,
    Our driver is not in the kernel tree yet.
    The code snippet from poll entry point is as follows:

    mask = 0;
    poll_wait(filp, &(sap_desc->recv_any_wq), poll_table);
    /* We don't have yet a waiting queue for writers... */
    lock_mts();
    if ((sap_desc->recv_q.first != NULL) &&
    (block_ssync_event(sap_desc->recv_q.first) == FALSE)) {
    /* The queue can be read. */
    mask |= POLLIN | POLLRDNORM;
    }
    unlock_mts();
    //MTS_HOOK(mts_syscall_exit,__FUNCTION__,mask);
    return mask;

    The wake_up_interruptible(&(sap_desc->recv_any_wq)) is executed
    from the sending process.

    Hope this is sufficient. As I mentioned in my previous mail, what I
    am trying to understand better is the kernel code path of do_select()
    versus wake_up_interruptible.

    Thanks,
    Ravi

    -----Original Message-----
    From: Arjan van de Ven [mailto:arjan@infradead.org]
    Sent: Wednesday, March 14, 2007 4:08 AM
    To: Ravinandan Arakali (rarakali)
    Cc: linux-kernel@vger.kernel.org
    Subject: Re: Clarification required about select vs wake_up race
    condition

    On Mon, 2007-03-12 at 12:44 -0700, Ravinandan Arakali (rarakali) wrote:
    > Hi,
    > I am facing following problem and was wondering if somebody could help

    > me out.
    > Our char driver(pretty much like all other char drivers) does a
    > poll_wait()


    you forgot to include your (full) sourcecode or a pointer to that...
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2007-03-14 17:37    [W:0.029 / U:0.852 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site