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-rw-r--r--kernel/time/time.c53
1 files changed, 28 insertions, 25 deletions
diff --git a/kernel/time/time.c b/kernel/time/time.c
index 85d5bb1d67eb..86751c68e08d 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -268,10 +268,14 @@ EXPORT_SYMBOL(jiffies_to_msecs);
unsigned int jiffies_to_usecs(const unsigned long j)
{
-#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ)
+ /*
+ * Hz usually doesn't go much further MSEC_PER_SEC.
+ * jiffies_to_usecs() and usecs_to_jiffies() depend on that.
+ */
+ BUILD_BUG_ON(HZ > USEC_PER_SEC);
+
+#if !(USEC_PER_SEC % HZ)
return (USEC_PER_SEC / HZ) * j;
-#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC)
- return (j + (HZ / USEC_PER_SEC) - 1)/(HZ / USEC_PER_SEC);
#else
# if BITS_PER_LONG == 32
return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32;
@@ -287,26 +291,20 @@ EXPORT_SYMBOL(jiffies_to_usecs);
* @t: Timespec
* @gran: Granularity in ns.
*
- * Truncate a timespec to a granularity. gran must be smaller than a second.
- * Always rounds down.
- *
- * This function should be only used for timestamps returned by
- * current_kernel_time() or CURRENT_TIME, not with do_gettimeofday() because
- * it doesn't handle the better resolution of the latter.
+ * Truncate a timespec to a granularity. Always rounds down. gran must
+ * not be 0 nor greater than a second (NSEC_PER_SEC, or 10^9 ns).
*/
struct timespec timespec_trunc(struct timespec t, unsigned gran)
{
- /*
- * Division is pretty slow so avoid it for common cases.
- * Currently current_kernel_time() never returns better than
- * jiffies resolution. Exploit that.
- */
- if (gran <= jiffies_to_usecs(1) * 1000) {
+ /* Avoid division in the common cases 1 ns and 1 s. */
+ if (gran == 1) {
/* nothing */
- } else if (gran == 1000000000) {
+ } else if (gran == NSEC_PER_SEC) {
t.tv_nsec = 0;
- } else {
+ } else if (gran > 1 && gran < NSEC_PER_SEC) {
t.tv_nsec -= t.tv_nsec % gran;
+ } else {
+ WARN(1, "illegal file time granularity: %u", gran);
}
return t;
}
@@ -546,7 +544,7 @@ EXPORT_SYMBOL(__usecs_to_jiffies);
* value to a scaled second value.
*/
static unsigned long
-__timespec_to_jiffies(unsigned long sec, long nsec)
+__timespec64_to_jiffies(u64 sec, long nsec)
{
nsec = nsec + TICK_NSEC - 1;
@@ -554,22 +552,27 @@ __timespec_to_jiffies(unsigned long sec, long nsec)
sec = MAX_SEC_IN_JIFFIES;
nsec = 0;
}
- return (((u64)sec * SEC_CONVERSION) +
+ return ((sec * SEC_CONVERSION) +
(((u64)nsec * NSEC_CONVERSION) >>
(NSEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC;
}
-unsigned long
-timespec_to_jiffies(const struct timespec *value)
+static unsigned long
+__timespec_to_jiffies(unsigned long sec, long nsec)
{
- return __timespec_to_jiffies(value->tv_sec, value->tv_nsec);
+ return __timespec64_to_jiffies((u64)sec, nsec);
}
-EXPORT_SYMBOL(timespec_to_jiffies);
+unsigned long
+timespec64_to_jiffies(const struct timespec64 *value)
+{
+ return __timespec64_to_jiffies(value->tv_sec, value->tv_nsec);
+}
+EXPORT_SYMBOL(timespec64_to_jiffies);
void
-jiffies_to_timespec(const unsigned long jiffies, struct timespec *value)
+jiffies_to_timespec64(const unsigned long jiffies, struct timespec64 *value)
{
/*
* Convert jiffies to nanoseconds and separate with
@@ -580,7 +583,7 @@ jiffies_to_timespec(const unsigned long jiffies, struct timespec *value)
NSEC_PER_SEC, &rem);
value->tv_nsec = rem;
}
-EXPORT_SYMBOL(jiffies_to_timespec);
+EXPORT_SYMBOL(jiffies_to_timespec64);
/*
* We could use a similar algorithm to timespec_to_jiffies (with a