2.6.26-rc1

 kernel

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 31e9f2a..36e0617 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -356,7 +356,8 @@ void open_softirq(int nr, void (*action)(struct softirq_action*), void *data)
 /* Tasklets */
 struct tasklet_head
 {
-   struct tasklet_struct *list;
+   struct tasklet_struct *head;
+   struct tasklet_struct **tail;
 };
 
 /* Some compilers disobey section attribute on statics when not
@@ -369,8 +370,9 @@ void __tasklet_schedule(struct tasklet_struct *t)
    unsigned long flags;
 
    local_irq_save(flags);
-   t->next = __get_cpu_var(tasklet_vec).list;
-   __get_cpu_var(tasklet_vec).list = t;
+   t->next = NULL;
+   *__get_cpu_var(tasklet_vec).tail = t;
+   __get_cpu_var(tasklet_vec).tail = &(t->next);
    raise_softirq_irqoff(TASKLET_SOFTIRQ);
    local_irq_restore(flags);
 }
@@ -382,8 +384,9 @@ void __tasklet_hi_schedule(struct tasklet_struct *t)
    unsigned long flags;
 
    local_irq_save(flags);
-   t->next = __get_cpu_var(tasklet_hi_vec).list;
-   __get_cpu_var(tasklet_hi_vec).list = t;
+   t->next = NULL;
+   *__get_cpu_var(tasklet_hi_vec).tail = t;
+   __get_cpu_var(tasklet_hi_vec).tail = &(t->next);
    raise_softirq_irqoff(HI_SOFTIRQ);
    local_irq_restore(flags);
 }
@@ -395,8 +398,9 @@ static void tasklet_action(struct softirq_action *a)
    struct tasklet_struct *list;
 
    local_irq_disable();
-   list = __get_cpu_var(tasklet_vec).list;
-   __get_cpu_var(tasklet_vec).list = NULL;
+   list = __get_cpu_var(tasklet_vec).head;
+   __get_cpu_var(tasklet_vec).head = NULL;
+   __get_cpu_var(tasklet_vec).tail = &__get_cpu_var(tasklet_vec).head;
    local_irq_enable();
 
    while (list) {
@@ -416,8 +420,9 @@ static void tasklet_action(struct softirq_action *a)
       }
 
       local_irq_disable();
-      t->next = __get_cpu_var(tasklet_vec).list;
-      __get_cpu_var(tasklet_vec).list = t;
+      t->next = NULL;
+      *__get_cpu_var(tasklet_vec).tail = t;
+      __get_cpu_var(tasklet_vec).tail = &(t->next);
       __raise_softirq_irqoff(TASKLET_SOFTIRQ);
       local_irq_enable();
    }
@@ -428,8 +433,9 @@ static void tasklet_hi_action(struct softirq_action *a)
    struct tasklet_struct *list;
 
    local_irq_disable();
-   list = __get_cpu_var(tasklet_hi_vec).list;
-   __get_cpu_var(tasklet_hi_vec).list = NULL;
+   list = __get_cpu_var(tasklet_hi_vec).head;
+   __get_cpu_var(tasklet_hi_vec).head = NULL;
+   __get_cpu_var(tasklet_hi_vec).tail = &__get_cpu_var(tasklet_hi_vec).head;
    local_irq_enable();
 
    while (list) {
@@ -449,8 +455,9 @@ static void tasklet_hi_action(struct softirq_action *a)
       }
 
       local_irq_disable();
-      t->next = __get_cpu_var(tasklet_hi_vec).list;
-      __get_cpu_var(tasklet_hi_vec).list = t;
+      t->next = NULL;
+      *__get_cpu_var(tasklet_hi_vec).tail = t;
+      __get_cpu_var(tasklet_hi_vec).tail = &(t->next);
       __raise_softirq_irqoff(HI_SOFTIRQ);
       local_irq_enable();
    }
@@ -487,6 +494,15 @@ EXPORT_SYMBOL(tasklet_kill);
 
 void __init softirq_init(void)
 {
+   int cpu;
+
+   for_each_possible_cpu(cpu) {
+      per_cpu(tasklet_vec, cpu).tail =
+         &per_cpu(tasklet_vec, cpu).head;
+      per_cpu(tasklet_hi_vec, cpu).tail =
+         &per_cpu(tasklet_hi_vec, cpu).head;
+   }
+
    open_softirq(TASKLET_SOFTIRQ, tasklet_action, NULL);
    open_softirq(HI_SOFTIRQ, tasklet_hi_action, NULL);
 }
@@ -555,9 +571,12 @@ void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu)
       return;
 
    /* CPU is dead, so no lock needed. */
-   for (i = &per_cpu(tasklet_vec, cpu).list; *i; i = &(*i)->next) {
+   for (i = &per_cpu(tasklet_vec, cpu).head; *i; i = &(*i)->next) {
       if (*i == t) {
          *i = t->next;
+         /* If this was the tail element, move the tail ptr */
+         if (*i == NULL)
+            per_cpu(tasklet_vec, cpu).tail = i;
          return;
       }
    }
@@ -566,20 +585,24 @@ void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu)
 
 static void takeover_tasklets(unsigned int cpu)
 {
-   struct tasklet_struct **i;
-
    /* CPU is dead, so no lock needed. */
    local_irq_disable();
 
    /* Find end, append list for that CPU. */
-   for (i = &__get_cpu_var(tasklet_vec).list; *i; i = &(*i)->next);
-   *i = per_cpu(tasklet_vec, cpu).list;
-   per_cpu(tasklet_vec, cpu).list = NULL;
+   if (&per_cpu(tasklet_vec, cpu).head != per_cpu(tasklet_vec, cpu).tail) {
+      *(__get_cpu_var(tasklet_vec).tail) = per_cpu(tasklet_vec, cpu).head;
+      __get_cpu_var(tasklet_vec).tail = per_cpu(tasklet_vec, cpu).tail;
+      per_cpu(tasklet_vec, cpu).head = NULL;
+      per_cpu(tasklet_vec, cpu).tail = &per_cpu(tasklet_vec, cpu).head;
+   }
    raise_softirq_irqoff(TASKLET_SOFTIRQ);
 
-   for (i = &__get_cpu_var(tasklet_hi_vec).list; *i; i = &(*i)->next);
-   *i = per_cpu(tasklet_hi_vec, cpu).list;
-   per_cpu(tasklet_hi_vec, cpu).list = NULL;
+   if (&per_cpu(tasklet_hi_vec, cpu).head != per_cpu(tasklet_hi_vec, cpu).tail) {
+      *__get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).head;
+      __get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).tail;
+      per_cpu(tasklet_hi_vec, cpu).head = NULL;
+      per_cpu(tasklet_hi_vec, cpu).tail = &per_cpu(tasklet_hi_vec, cpu).head;
+   }
    raise_softirq_irqoff(HI_SOFTIRQ);
 
    local_irq_enable();