Re: [PATCH] Remove defered timer list in favor of moving the list time update

[george anzinger <george@mvista.com>]

[-- Attachment #1: Type: text/plain, Size: 1172 bytes --]

Andrew Morton wrote:
> george anzinger <george@mvista.com> wrote:
> 
>>I found a problem with the last version.  The attached is for 
>>2.5.65-1.1171 (i.e. after the other post 2.5.65 changes).  The bug is 
>>fixed, and theAndrew Morton wrote:
 > george anzinger <george@mvista.com> wrote:
 >
 >>I found a problem with the last version.  The attached is for
 >>2.5.65-1.1171 (i.e. after the other post 2.5.65 changes).  The bug is
 >>fixed, and the code even simpler here.
 >
 >
 > Thanks, I'll queue that up after Tim's stuff is merged.

And this removes the defered queue in favor of just moving the list 
time update to just prior to the repeat label.  (Apply after my 
"bumps" patch.)

Do I have the right Andrea?
 >
 >

-- 
George Anzinger   george@mvista.com
High-res-timers:  http://sourceforge.net/projects/high-res-timers/
Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml
  code even simpler here.
> 
> 
> Thanks, I'll queue that up after Tim's stuff is merged.
> 
> 

-- 
George Anzinger   george@mvista.com
High-res-timers:  http://sourceforge.net/projects/high-res-timers/
Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml

[-- Attachment #2: hrtimers-run-def.patch --]
[-- Type: text/plain, Size: 2022 bytes --]

--- linux-2.5.65-1.1171-run/kernel/timer.cX	2003-03-19 13:08:24.000000000 -0800
+++ linux/kernel/timer.c	2003-03-19 14:16:53.000000000 -0800
@@ -55,7 +55,6 @@
 	spinlock_t lock;
 	unsigned long timer_jiffies;
 	struct timer_list *running_timer;
-	struct list_head *run_timer_list_running;
 	tvec_root_t tv1;
 	tvec_t tv2;
 	tvec_t tv3;
@@ -100,12 +99,6 @@
 		check_timer_failed(timer);
 }
 
-/*
- * If a timer handler re-adds the timer with expires == jiffies, the timer
- * running code can lock up.  So here we detect that situation and park the
- * timer onto base->run_timer_list_running.  It will be added to the main timer
- * structures later, by __run_timers().
- */
 
 static void internal_add_timer(tvec_base_t *base, struct timer_list *timer)
 {
@@ -113,9 +106,7 @@
 	unsigned long idx = expires - base->timer_jiffies;
 	struct list_head *vec;
 
-	if (base->run_timer_list_running) {
-		vec = base->run_timer_list_running;
-	} else if (idx < TVR_SIZE) {
+	if (idx < TVR_SIZE) {
 		int i = expires & TVR_MASK;
 		vec = base->tv1.vec + i;
 	} else if (idx < 1 << (TVR_BITS + TVN_BITS)) {
@@ -405,7 +396,6 @@
 
 	spin_lock_irq(&base->lock);
 	while (time_after_eq(jiffies, base->timer_jiffies)) {
-		LIST_HEAD(deferred_timers);
 		struct list_head *head;
  		int index = base->timer_jiffies & TVR_MASK;
  
@@ -417,7 +407,7 @@
 				(! cascade(base, &base->tv3, INDEX(1))) &&
 					! cascade(base, &base->tv4, INDEX(2)))
 			cascade(base, &base->tv5, INDEX(3));
-		base->run_timer_list_running = &deferred_timers;
+		++base->timer_jiffies; 
 repeat:
 		head = base->tv1.vec + index;
 		if (!list_empty(head)) {
@@ -436,14 +426,6 @@
 			spin_lock_irq(&base->lock);
 			goto repeat;
 		}
-		base->run_timer_list_running = NULL;
-		++base->timer_jiffies; 
-		while (!list_empty(&deferred_timers)) {
-			timer = list_entry(deferred_timers.prev,
-						struct timer_list, entry);
-			list_del(&timer->entry);
-			internal_add_timer(base, timer);
-		}
 	}
 	set_running_timer(base, NULL);
 	spin_unlock_irq(&base->lock);