Re: [PATCH 2/13] use cpu_relax() in busy loop

[Chris Wright <chrisw@osdl.org>]

* 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);
 }