lkml.org 
[lkml]   [2003]   [Sep]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    SubjectRe: [PATCH 2/13] use cpu_relax() in busy loop
    * Arjan van de Ven (arjanv@redhat.com) wrote:
    > ehmmm how about making this use mdelay instead ?
    > (not to speak of maybe making it sleep, but that's a less obvious
    > transformation)

    I didn't want to change to sleep semantics of the call w/out better
    review of spinlocks held/irq disabled, etc. But, after feedback from
    Mitch, looks like these were only called during module init/exit. This
    look ok?

    thanks,
    -chris

    [PATCH 2/13] use schedule_timeout() instead of busy loop

    Replace fore200e_spin() busy loops with schedule_timeout().

    ===== fore200e.c 1.19 vs edited =====
    --- 1.19/drivers/atm/fore200e.c Tue Sep 2 11:07:59 2003
    +++ edited/fore200e.c Fri Sep 19 12:24:15 2003
    @@ -229,7 +229,8 @@
    u32 hb1, hb2;

    hb1 = fore200e->bus->read(&fore200e->cp_queues->heartbeat);
    - fore200e_spin(10);
    + set_current_state(TASK_UNINTERRUPTIBLE);
    + schedule_timeout(10 * HZ/1000);
    hb2 = fore200e->bus->read(&fore200e->cp_queues->heartbeat);

    if (hb2 <= hb1) {
    @@ -244,14 +245,6 @@
    #endif


    -static void
    -fore200e_spin(int msecs)
    -{
    - unsigned long timeout = jiffies + MSECS(msecs);
    - while (time_before(jiffies, timeout));
    -}
    -
    -
    static int
    fore200e_poll(struct fore200e* fore200e, volatile u32* addr, u32 val, int msecs)
    {
    @@ -551,7 +544,8 @@
    fore200e_pca_reset(struct fore200e* fore200e)
    {
    writel(PCA200E_HCR_RESET, fore200e->regs.pca.hcr);
    - fore200e_spin(10);
    + set_current_state(TASK_UNINTERRUPTIBLE);
    + schedule_timeout(10 * HZ/1000);
    writel(0, fore200e->regs.pca.hcr);
    }

    @@ -831,7 +825,8 @@
    fore200e_sba_reset(struct fore200e* fore200e)
    {
    fore200e->bus->write(SBA200E_HCR_RESET, fore200e->regs.sba.hcr);
    - fore200e_spin(10);
    + set_current_state(TASK_UNINTERRUPTIBLE);
    + schedule_timeout(10 * HZ/1000);
    fore200e->bus->write(0, fore200e->regs.sba.hcr);
    }

    -
    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: 2005-03-22 13:48    [W:0.038 / U:29.556 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site