Hook up group scheduler with control groups

[pandora-kernel.git] / kernel / hrtimer.c

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index c21ca6b..b2b2c2b 100644 (file)
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -277,6 +277,30 @@ ktime_t ktime_add_ns(const ktime_t kt, u64 nsec)
 }
 
 EXPORT_SYMBOL_GPL(ktime_add_ns);
+
+/**
+ * ktime_sub_ns - Subtract a scalar nanoseconds value from a ktime_t variable
+ * @kt:                minuend
+ * @nsec:      the scalar nsec value to subtract
+ *
+ * Returns the subtraction of @nsec from @kt in ktime_t format
+ */
+ktime_t ktime_sub_ns(const ktime_t kt, u64 nsec)
+{
+       ktime_t tmp;
+
+       if (likely(nsec < NSEC_PER_SEC)) {
+               tmp.tv64 = nsec;
+       } else {
+               unsigned long rem = do_div(nsec, NSEC_PER_SEC);
+
+               tmp = ktime_set((long)nsec, rem);
+       }
+
+       return ktime_sub(kt, tmp);
+}
+
+EXPORT_SYMBOL_GPL(ktime_sub_ns);
 # endif /* !CONFIG_KTIME_SCALAR */
 
 /*
@@ -1262,8 +1286,7 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
 long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 {
        struct hrtimer_sleeper t;
-       struct timespec __user *rmtp;
-       struct timespec tu;
+       struct timespec *rmtp;
        ktime_t time;
 
        restart->fn = do_no_restart_syscall;
@@ -1274,14 +1297,12 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
        if (do_nanosleep(&t, HRTIMER_MODE_ABS))
                return 0;
 
-       rmtp = (struct timespec __user *) restart->arg1;
+       rmtp = (struct timespec *)restart->arg1;
        if (rmtp) {
                time = ktime_sub(t.timer.expires, t.timer.base->get_time());
                if (time.tv64 <= 0)
                        return 0;
-               tu = ktime_to_timespec(time);
-               if (copy_to_user(rmtp, &tu, sizeof(tu)))
-                       return -EFAULT;
+               *rmtp = ktime_to_timespec(time);
        }
 
        restart->fn = hrtimer_nanosleep_restart;
@@ -1290,12 +1311,11 @@ long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
        return -ERESTART_RESTARTBLOCK;
 }
 
-long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
+long hrtimer_nanosleep(struct timespec *rqtp, struct timespec *rmtp,
                       const enum hrtimer_mode mode, const clockid_t clockid)
 {
        struct restart_block *restart;
        struct hrtimer_sleeper t;
-       struct timespec tu;
        ktime_t rem;
 
        hrtimer_init(&t.timer, clockid, mode);
@@ -1311,9 +1331,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
                rem = ktime_sub(t.timer.expires, t.timer.base->get_time());
                if (rem.tv64 <= 0)
                        return 0;
-               tu = ktime_to_timespec(rem);
-               if (copy_to_user(rmtp, &tu, sizeof(tu)))
-                       return -EFAULT;
+               *rmtp = ktime_to_timespec(rem);
        }
 
        restart = &current_thread_info()->restart_block;
@@ -1329,7 +1347,8 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
 asmlinkage long
 sys_nanosleep(struct timespec __user *rqtp, struct timespec __user *rmtp)
 {
-       struct timespec tu;
+       struct timespec tu, rmt;
+       int ret;
 
        if (copy_from_user(&tu, rqtp, sizeof(tu)))
                return -EFAULT;
@@ -1337,7 +1356,15 @@ sys_nanosleep(struct timespec __user *rqtp, struct timespec __user *rmtp)
        if (!timespec_valid(&tu))
                return -EINVAL;
 
-       return hrtimer_nanosleep(&tu, rmtp, HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+       ret = hrtimer_nanosleep(&tu, rmtp ? &rmt : NULL, HRTIMER_MODE_REL,
+                               CLOCK_MONOTONIC);
+
+       if (ret && rmtp) {
+               if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
+                       return -EFAULT;
+       }
+
+       return ret;
 }
 
 /*