hrtimers: Provide schedule_hrtimeout for CLOCK_REALTIME
The current version of schedule_hrtimeout() always uses the
monotonic clock. Some system calls such as mq_timedsend()
and mq_timedreceive(), however, require the use of the wall
clock due to the definition of the system call.
This patch provides the infrastructure to use schedule_hrtimeout()
with a CLOCK_REALTIME timer.
Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Tested-by: Pradyumna Sampath <pradysam@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Veen <arjan@infradead.org>
LKML-Reference: <20100402204331.167439615@osadl.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 0086628..b9b134b 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1749,6 +1749,57 @@
}
/**
+ * schedule_hrtimeout_range_clock - sleep until timeout
+ * @expires: timeout value (ktime_t)
+ * @delta: slack in expires timeout (ktime_t)
+ * @mode: timer mode, HRTIMER_MODE_ABS or HRTIMER_MODE_REL
+ * @clock: timer clock, CLOCK_MONOTONIC or CLOCK_REALTIME
+ */
+int __sched
+schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta,
+ const enum hrtimer_mode mode, int clock)
+{
+ struct hrtimer_sleeper t;
+
+ /*
+ * Optimize when a zero timeout value is given. It does not
+ * matter whether this is an absolute or a relative time.
+ */
+ if (expires && !expires->tv64) {
+ __set_current_state(TASK_RUNNING);
+ return 0;
+ }
+
+ /*
+ * A NULL parameter means "inifinte"
+ */
+ if (!expires) {
+ schedule();
+ __set_current_state(TASK_RUNNING);
+ return -EINTR;
+ }
+
+ hrtimer_init_on_stack(&t.timer, clock, mode);
+ hrtimer_set_expires_range_ns(&t.timer, *expires, delta);
+
+ hrtimer_init_sleeper(&t, current);
+
+ hrtimer_start_expires(&t.timer, mode);
+ if (!hrtimer_active(&t.timer))
+ t.task = NULL;
+
+ if (likely(t.task))
+ schedule();
+
+ hrtimer_cancel(&t.timer);
+ destroy_hrtimer_on_stack(&t.timer);
+
+ __set_current_state(TASK_RUNNING);
+
+ return !t.task ? 0 : -EINTR;
+}
+
+/**
* schedule_hrtimeout_range - sleep until timeout
* @expires: timeout value (ktime_t)
* @delta: slack in expires timeout (ktime_t)
@@ -1777,46 +1828,10 @@
* Returns 0 when the timer has expired otherwise -EINTR
*/
int __sched schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
- const enum hrtimer_mode mode)
+ const enum hrtimer_mode mode)
{
- struct hrtimer_sleeper t;
-
- /*
- * Optimize when a zero timeout value is given. It does not
- * matter whether this is an absolute or a relative time.
- */
- if (expires && !expires->tv64) {
- __set_current_state(TASK_RUNNING);
- return 0;
- }
-
- /*
- * A NULL parameter means "inifinte"
- */
- if (!expires) {
- schedule();
- __set_current_state(TASK_RUNNING);
- return -EINTR;
- }
-
- hrtimer_init_on_stack(&t.timer, CLOCK_MONOTONIC, mode);
- hrtimer_set_expires_range_ns(&t.timer, *expires, delta);
-
- hrtimer_init_sleeper(&t, current);
-
- hrtimer_start_expires(&t.timer, mode);
- if (!hrtimer_active(&t.timer))
- t.task = NULL;
-
- if (likely(t.task))
- schedule();
-
- hrtimer_cancel(&t.timer);
- destroy_hrtimer_on_stack(&t.timer);
-
- __set_current_state(TASK_RUNNING);
-
- return !t.task ? 0 : -EINTR;
+ return schedule_hrtimeout_range_clock(expires, delta, mode,
+ CLOCK_MONOTONIC);
}
EXPORT_SYMBOL_GPL(schedule_hrtimeout_range);
