From: Arjan van de Ven <arjan@linux.intel.com>
Date: Mon, 8 Sep 2008 15:58:59 +0000 (-0700)
Subject: hrtimer: make the nanosleep() syscall use the per process slack
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=3bd012060f962567aadb52b27b2fc8fdc91102c7;p=linux-beck.git

hrtimer: make the nanosleep() syscall use the per process slack

This patch makes the nanosleep() system call use the per process
slack value; with this users are able to externally control existing
applications to reduce the wakeup rate.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
---

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index a0222097c57e..9a4c90185566 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1563,9 +1563,14 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
 	struct restart_block *restart;
 	struct hrtimer_sleeper t;
 	int ret = 0;
+	unsigned long slack;
+
+	slack = current->timer_slack_ns;
+	if (rt_task(current))
+		slack = 0;
 
 	hrtimer_init_on_stack(&t.timer, clockid, mode);
-	hrtimer_set_expires(&t.timer, timespec_to_ktime(*rqtp));
+	hrtimer_set_expires_range_ns(&t.timer, timespec_to_ktime(*rqtp), slack);
 	if (do_nanosleep(&t, mode))
 		goto out;