posix_cpu_timers: consolidate timer list cleanups

Cleaning up the posix cpu timers on task exit shares some common code
among timer list types, most notably the list traversal and expiry time
update.

Unify this in a common helper.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index e5286b5492820d84a4c34d1fea0725a4cf7afbd7..b30775f88a4e2534e3300a92147a647ab88333fd 100644 (file)
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -382,6 +382,21 @@ static int posix_cpu_timer_del(struct k_itimer *timer)
        return ret;
 }
 
+static void cleanup_timers_list(struct list_head *head,
+                               unsigned long long curr)
+{
+       struct cpu_timer_list *timer, *next;
+
+       list_for_each_entry_safe(timer, next, head, entry) {
+               list_del_init(&timer->entry);
+               if (timer->expires < curr) {
+                       timer->expires = 0;
+               } else {
+                       timer->expires -= curr;
+               }
+       }
+}
+
 /*
  * Clean out CPU timers still ticking when a thread exited.  The task
  * pointer is cleared, and the expiry time is replaced with the residual
@@ -392,37 +407,12 @@ static void cleanup_timers(struct list_head *head,
                           cputime_t utime, cputime_t stime,
                           unsigned long long sum_exec_runtime)
 {
-       struct cpu_timer_list *timer, *next;
-       cputime_t ptime = utime + stime;
 
-       list_for_each_entry_safe(timer, next, head, entry) {
-               list_del_init(&timer->entry);
-               if (timer->expires < cputime_to_expires(ptime)) {
-                       timer->expires = 0;
-               } else {
-                       timer->expires -= cputime_to_expires(ptime);
-               }
-       }
-
-       ++head;
-       list_for_each_entry_safe(timer, next, head, entry) {
-               list_del_init(&timer->entry);
-               if (timer->expires < cputime_to_expires(utime)) {
-                       timer->expires = 0;
-               } else {
-                       timer->expires -= cputime_to_expires(utime);
-               }
-       }
+       cputime_t ptime = utime + stime;
 
-       ++head;
-       list_for_each_entry_safe(timer, next, head, entry) {
-               list_del_init(&timer->entry);
-               if (timer->expires < sum_exec_runtime) {
-                       timer->expires = 0;
-               } else {
-                       timer->expires -= sum_exec_runtime;
-               }
-       }
+       cleanup_timers_list(head, cputime_to_expires(ptime));
+       cleanup_timers_list(++head, cputime_to_expires(utime));
+       cleanup_timers_list(++head, sum_exec_runtime);
 }
 
 /*