X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fposix-timers.c;h=329ce0172074a8270b662e3850118d08d42c0dc0;hb=57a9f236ebe76be6fe1c85b5f7b3cea842e44177;hp=a1bf616178394f1906a11bb2bb063d16cb3b5902;hpb=c827ba4cb49a30ce581201fd0ba2be77cde412c7;p=linux-2.6-omap-h63xx.git

diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index a1bf6161783..329ce017207 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -31,7 +31,6 @@
  * POSIX clocks & timers
  */
 #include <linux/mm.h>
-#include <linux/smp_lock.h>
 #include <linux/interrupt.h>
 #include <linux/slab.h>
 #include <linux/time.h>
@@ -145,7 +144,7 @@ static int common_timer_set(struct k_itimer *, int,
 			    struct itimerspec *, struct itimerspec *);
 static int common_timer_del(struct k_itimer *timer);
 
-static int posix_timer_fn(struct hrtimer *data);
+static enum hrtimer_restart posix_timer_fn(struct hrtimer *data);
 
 static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags);
 
@@ -334,12 +333,12 @@ EXPORT_SYMBOL_GPL(posix_timer_event);
 
  * This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
  */
-static int posix_timer_fn(struct hrtimer *timer)
+static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
 {
 	struct k_itimer *timr;
 	unsigned long flags;
 	int si_private = 0;
-	int ret = HRTIMER_NORESTART;
+	enum hrtimer_restart ret = HRTIMER_NORESTART;
 
 	timr = container_of(timer, struct k_itimer, it.real.timer);
 	spin_lock_irqsave(&timr->it_lock, flags);
@@ -354,9 +353,40 @@ static int posix_timer_fn(struct hrtimer *timer)
 		 * it should be restarted.
 		 */
 		if (timr->it.real.interval.tv64 != 0) {
+			ktime_t now = hrtimer_cb_get_time(timer);
+
+			/*
+			 * FIXME: What we really want, is to stop this
+			 * timer completely and restart it in case the
+			 * SIG_IGN is removed. This is a non trivial
+			 * change which involves sighand locking
+			 * (sigh !), which we don't want to do late in
+			 * the release cycle.
+			 *
+			 * For now we just let timers with an interval
+			 * less than a jiffie expire every jiffie to
+			 * avoid softirq starvation in case of SIG_IGN
+			 * and a very small interval, which would put
+			 * the timer right back on the softirq pending
+			 * list. By moving now ahead of time we trick
+			 * hrtimer_forward() to expire the timer
+			 * later, while we still maintain the overrun
+			 * accuracy, but have some inconsistency in
+			 * the timer_gettime() case. This is at least
+			 * better than a starved softirq. A more
+			 * complex fix which solves also another related
+			 * inconsistency is already in the pipeline.
+			 */
+#ifdef CONFIG_HIGH_RES_TIMERS
+			{
+				ktime_t kj = ktime_set(0, NSEC_PER_SEC / HZ);
+
+				if (timr->it.real.interval.tv64 < kj.tv64)
+					now = ktime_add(now, kj);
+			}
+#endif
 			timr->it_overrun +=
-				hrtimer_forward(timer,
-						timer->base->softirq_time,
+				hrtimer_forward(timer, now,
 						timr->it.real.interval);
 			ret = HRTIMER_RESTART;
 			++timr->it_requeue_pending;
@@ -722,7 +752,7 @@ common_timer_set(struct k_itimer *timr, int flags,
 	if (!new_setting->it_value.tv_sec && !new_setting->it_value.tv_nsec)
 		return 0;
 
-	mode = flags & TIMER_ABSTIME ? HRTIMER_ABS : HRTIMER_REL;
+	mode = flags & TIMER_ABSTIME ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL;
 	hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
 	timr->it.real.timer.function = posix_timer_fn;
 
@@ -734,7 +764,7 @@ common_timer_set(struct k_itimer *timr, int flags,
 	/* SIGEV_NONE timers are not queued ! See common_timer_get */
 	if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
 		/* Setup correct expiry time for relative timers */
-		if (mode == HRTIMER_REL)
+		if (mode == HRTIMER_MODE_REL)
 			timer->expires = ktime_add(timer->expires,
 						   timer->base->get_time());
 		return 0;
@@ -950,7 +980,8 @@ static int common_nsleep(const clockid_t which_clock, int flags,
 			 struct timespec *tsave, struct timespec __user *rmtp)
 {
 	return hrtimer_nanosleep(tsave, rmtp, flags & TIMER_ABSTIME ?
-				 HRTIMER_ABS : HRTIMER_REL, which_clock);
+				 HRTIMER_MODE_ABS : HRTIMER_MODE_REL,
+				 which_clock);
 }
 
 asmlinkage long