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-rw-r--r--include/linux/jiffies.h222
1 files changed, 19 insertions, 203 deletions
diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h
index 0ec6e28bccd..c080f61fb02 100644
--- a/include/linux/jiffies.h
+++ b/include/linux/jiffies.h
@@ -142,13 +142,13 @@ static inline u64 get_jiffies_64(void)
*
* And some not so obvious.
*
- * Note that we don't want to return MAX_LONG, because
+ * Note that we don't want to return LONG_MAX, because
* for various timeout reasons we often end up having
* to wait "jiffies+1" in order to guarantee that we wait
* at _least_ "jiffies" - so "jiffies+1" had better still
* be positive.
*/
-#define MAX_JIFFY_OFFSET ((~0UL >> 1)-1)
+#define MAX_JIFFY_OFFSET ((LONG_MAX >> 1)-1)
/*
* We want to do realistic conversions of time so we need to use the same
@@ -259,207 +259,23 @@ static inline u64 get_jiffies_64(void)
#endif
/*
- * Convert jiffies to milliseconds and back.
- *
- * Avoid unnecessary multiplications/divisions in the
- * two most common HZ cases:
- */
-static inline unsigned int jiffies_to_msecs(const unsigned long j)
-{
-#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ)
- return (MSEC_PER_SEC / HZ) * j;
-#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC)
- return (j + (HZ / MSEC_PER_SEC) - 1)/(HZ / MSEC_PER_SEC);
-#else
- return (j * MSEC_PER_SEC) / HZ;
-#endif
-}
-
-static inline unsigned int jiffies_to_usecs(const unsigned long j)
-{
-#if HZ <= USEC_PER_SEC && !(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
- return (j * USEC_PER_SEC) / HZ;
-#endif
-}
-
-static inline unsigned long msecs_to_jiffies(const unsigned int m)
-{
- if (m > jiffies_to_msecs(MAX_JIFFY_OFFSET))
- return MAX_JIFFY_OFFSET;
-#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ)
- return (m + (MSEC_PER_SEC / HZ) - 1) / (MSEC_PER_SEC / HZ);
-#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC)
- return m * (HZ / MSEC_PER_SEC);
-#else
- return (m * HZ + MSEC_PER_SEC - 1) / MSEC_PER_SEC;
-#endif
-}
-
-static inline unsigned long usecs_to_jiffies(const unsigned int u)
-{
- if (u > jiffies_to_usecs(MAX_JIFFY_OFFSET))
- return MAX_JIFFY_OFFSET;
-#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ)
- return (u + (USEC_PER_SEC / HZ) - 1) / (USEC_PER_SEC / HZ);
-#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC)
- return u * (HZ / USEC_PER_SEC);
-#else
- return (u * HZ + USEC_PER_SEC - 1) / USEC_PER_SEC;
-#endif
-}
-
-/*
- * The TICK_NSEC - 1 rounds up the value to the next resolution. Note
- * that a remainder subtract here would not do the right thing as the
- * resolution values don't fall on second boundries. I.e. the line:
- * nsec -= nsec % TICK_NSEC; is NOT a correct resolution rounding.
- *
- * Rather, we just shift the bits off the right.
- *
- * The >> (NSEC_JIFFIE_SC - SEC_JIFFIE_SC) converts the scaled nsec
- * value to a scaled second value.
- */
-static __inline__ unsigned long
-timespec_to_jiffies(const struct timespec *value)
-{
- unsigned long sec = value->tv_sec;
- long nsec = value->tv_nsec + TICK_NSEC - 1;
-
- if (sec >= MAX_SEC_IN_JIFFIES){
- sec = MAX_SEC_IN_JIFFIES;
- nsec = 0;
- }
- return (((u64)sec * SEC_CONVERSION) +
- (((u64)nsec * NSEC_CONVERSION) >>
- (NSEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC;
-
-}
-
-static __inline__ void
-jiffies_to_timespec(const unsigned long jiffies, struct timespec *value)
-{
- /*
- * Convert jiffies to nanoseconds and separate with
- * one divide.
- */
- u64 nsec = (u64)jiffies * TICK_NSEC;
- value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &value->tv_nsec);
-}
-
-/* Same for "timeval"
- *
- * Well, almost. The problem here is that the real system resolution is
- * in nanoseconds and the value being converted is in micro seconds.
- * Also for some machines (those that use HZ = 1024, in-particular),
- * there is a LARGE error in the tick size in microseconds.
-
- * The solution we use is to do the rounding AFTER we convert the
- * microsecond part. Thus the USEC_ROUND, the bits to be shifted off.
- * Instruction wise, this should cost only an additional add with carry
- * instruction above the way it was done above.
- */
-static __inline__ unsigned long
-timeval_to_jiffies(const struct timeval *value)
-{
- unsigned long sec = value->tv_sec;
- long usec = value->tv_usec;
-
- if (sec >= MAX_SEC_IN_JIFFIES){
- sec = MAX_SEC_IN_JIFFIES;
- usec = 0;
- }
- return (((u64)sec * SEC_CONVERSION) +
- (((u64)usec * USEC_CONVERSION + USEC_ROUND) >>
- (USEC_JIFFIE_SC - SEC_JIFFIE_SC))) >> SEC_JIFFIE_SC;
-}
-
-static __inline__ void
-jiffies_to_timeval(const unsigned long jiffies, struct timeval *value)
-{
- /*
- * Convert jiffies to nanoseconds and separate with
- * one divide.
- */
- u64 nsec = (u64)jiffies * TICK_NSEC;
- long tv_usec;
-
- value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &tv_usec);
- tv_usec /= NSEC_PER_USEC;
- value->tv_usec = tv_usec;
-}
-
-/*
- * Convert jiffies/jiffies_64 to clock_t and back.
+ * Convert various time units to each other:
*/
-static inline clock_t jiffies_to_clock_t(long x)
-{
-#if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0
- return x / (HZ / USER_HZ);
-#else
- u64 tmp = (u64)x * TICK_NSEC;
- do_div(tmp, (NSEC_PER_SEC / USER_HZ));
- return (long)tmp;
-#endif
-}
-
-static inline unsigned long clock_t_to_jiffies(unsigned long x)
-{
-#if (HZ % USER_HZ)==0
- if (x >= ~0UL / (HZ / USER_HZ))
- return ~0UL;
- return x * (HZ / USER_HZ);
-#else
- u64 jif;
-
- /* Don't worry about loss of precision here .. */
- if (x >= ~0UL / HZ * USER_HZ)
- return ~0UL;
-
- /* .. but do try to contain it here */
- jif = x * (u64) HZ;
- do_div(jif, USER_HZ);
- return jif;
-#endif
-}
-
-static inline u64 jiffies_64_to_clock_t(u64 x)
-{
-#if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0
- do_div(x, HZ / USER_HZ);
-#else
- /*
- * There are better ways that don't overflow early,
- * but even this doesn't overflow in hundreds of years
- * in 64 bits, so..
- */
- x *= TICK_NSEC;
- do_div(x, (NSEC_PER_SEC / USER_HZ));
-#endif
- return x;
-}
-
-static inline u64 nsec_to_clock_t(u64 x)
-{
-#if (NSEC_PER_SEC % USER_HZ) == 0
- do_div(x, (NSEC_PER_SEC / USER_HZ));
-#elif (USER_HZ % 512) == 0
- x *= USER_HZ/512;
- do_div(x, (NSEC_PER_SEC / 512));
-#else
- /*
- * max relative error 5.7e-8 (1.8s per year) for USER_HZ <= 1024,
- * overflow after 64.99 years.
- * exact for HZ=60, 72, 90, 120, 144, 180, 300, 600, 900, ...
- */
- x *= 9;
- do_div(x, (unsigned long)((9ull * NSEC_PER_SEC + (USER_HZ/2))
- / USER_HZ));
-#endif
- return x;
-}
+extern unsigned int jiffies_to_msecs(const unsigned long j);
+extern unsigned int jiffies_to_usecs(const unsigned long j);
+extern unsigned long msecs_to_jiffies(const unsigned int m);
+extern unsigned long usecs_to_jiffies(const unsigned int u);
+extern unsigned long timespec_to_jiffies(const struct timespec *value);
+extern void jiffies_to_timespec(const unsigned long jiffies,
+ struct timespec *value);
+extern unsigned long timeval_to_jiffies(const struct timeval *value);
+extern void jiffies_to_timeval(const unsigned long jiffies,
+ struct timeval *value);
+extern clock_t jiffies_to_clock_t(long x);
+extern unsigned long clock_t_to_jiffies(unsigned long x);
+extern u64 jiffies_64_to_clock_t(u64 x);
+extern u64 nsec_to_clock_t(u64 x);
+
+#define TIMESTAMP_SIZE 30
#endif
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