From d4a00525d01345456bbba07514a9dc083f4b5b26 Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <fweisbec@gmail.com>
Date: Wed, 20 Mar 2013 15:06:56 +1100
Subject: [PATCH] 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>
---
 kernel/posix-cpu-timers.c | 48 ++++++++++++++++-----------------------
 1 file changed, 19 insertions(+), 29 deletions(-)

diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index e5286b549282..b30775f88a4e 100644
--- 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);
 }
 
 /*
-- 
2.39.5