diff options
| -rw-r--r-- | include/linux/jiffies.h | 136 | ||||
| -rw-r--r-- | kernel/time.c | 106 |
2 files changed, 98 insertions, 144 deletions
diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h index 69cfc6e09..c039fe131 100644 --- a/include/linux/jiffies.h +++ b/include/linux/jiffies.h @@ -276,138 +276,10 @@ extern unsigned long preset_lpj; /* * Convert various time units to each other: */ - -/* - * Avoid unnecessary multiplications/divisions in the - * two most common HZ cases: - */ -static __always_inline unsigned int -__inline_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 -# if BITS_PER_LONG == 32 - return (HZ_TO_MSEC_MUL32 * j) >> HZ_TO_MSEC_SHR32; -# else - return (j * HZ_TO_MSEC_NUM) / HZ_TO_MSEC_DEN; -# endif -#endif -} -extern unsigned int __jiffies_to_msecs(const unsigned long j); - -#define jiffies_to_msecs(x) \ - (__builtin_constant_p(x) ? \ - __inline_jiffies_to_msecs(x) : \ - __jiffies_to_msecs(x)) - -static __always_inline unsigned int -__inline_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 -# if BITS_PER_LONG == 32 - return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32; -# else - return (j * HZ_TO_USEC_NUM) / HZ_TO_USEC_DEN; -# endif -#endif -} -extern unsigned int __jiffies_to_usecs(const unsigned long j); - -#define jiffies_to_usecs(x) \ - (__builtin_constant_p(x) ? \ - __inline_jiffies_to_usecs(x) : \ - __jiffies_to_usecs(x)) - -/* - * When we convert to jiffies then we interpret incoming values - * the following way: - * - * - negative values mean 'infinite timeout' (MAX_JIFFY_OFFSET) - * - * - 'too large' values [that would result in larger than - * MAX_JIFFY_OFFSET values] mean 'infinite timeout' too. - * - * - all other values are converted to jiffies by either multiplying - * the input value by a factor or dividing it with a factor - * - * We must also be careful about 32-bit overflows. - */ -static __always_inline unsigned long -__inline_msecs_to_jiffies(const unsigned int m) -{ - /* - * Negative value, means infinite timeout: - */ - if ((int)m < 0) - return MAX_JIFFY_OFFSET; - -#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ) - /* - * HZ is equal to or smaller than 1000, and 1000 is a nice - * round multiple of HZ, divide with the factor between them, - * but round upwards: - */ - return (m + (MSEC_PER_SEC / HZ) - 1) / (MSEC_PER_SEC / HZ); -#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC) - /* - * HZ is larger than 1000, and HZ is a nice round multiple of - * 1000 - simply multiply with the factor between them. - * - * But first make sure the multiplication result cannot - * overflow: - */ - if (m > jiffies_to_msecs(MAX_JIFFY_OFFSET)) - return MAX_JIFFY_OFFSET; - - return m * (HZ / MSEC_PER_SEC); -#else - /* - * Generic case - multiply, round and divide. But first - * check that if we are doing a net multiplication, that - * we wouldn't overflow: - */ - if (HZ > MSEC_PER_SEC && m > jiffies_to_msecs(MAX_JIFFY_OFFSET)) - return MAX_JIFFY_OFFSET; - - return (MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32) - >> MSEC_TO_HZ_SHR32; -#endif -} -extern unsigned long __msecs_to_jiffies(const unsigned int m); - -#define msecs_to_jiffies(x) \ - (__builtin_constant_p(x) ? \ - __inline_msecs_to_jiffies(x) : \ - __msecs_to_jiffies(x)) - -static __always_inline unsigned long -__inline_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 (USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32) - >> USEC_TO_HZ_SHR32; -#endif -} -extern unsigned long __usecs_to_jiffies(const unsigned int u); - -#define usecs_to_jiffies(x) \ - (__builtin_constant_p(x) ? \ - __inline_usecs_to_jiffies(x) : \ - __usecs_to_jiffies(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); diff --git a/kernel/time.c b/kernel/time.c index 27dc71b73..5d4d9a024 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -244,18 +244,41 @@ EXPORT_SYMBOL(current_fs_time); /* * Convert jiffies to milliseconds and back. + * + * Avoid unnecessary multiplications/divisions in the + * two most common HZ cases: */ -unsigned int __jiffies_to_msecs(const unsigned long j) +unsigned int jiffies_to_msecs(const unsigned long j) { - return __inline_jiffies_to_msecs(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 +# if BITS_PER_LONG == 32 + return (HZ_TO_MSEC_MUL32 * j) >> HZ_TO_MSEC_SHR32; +# else + return (j * HZ_TO_MSEC_NUM) / HZ_TO_MSEC_DEN; +# endif +#endif } -EXPORT_SYMBOL(__jiffies_to_msecs); +EXPORT_SYMBOL(jiffies_to_msecs); -unsigned int __jiffies_to_usecs(const unsigned long j) +unsigned int jiffies_to_usecs(const unsigned long j) { - return __inline_jiffies_to_usecs(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 +# if BITS_PER_LONG == 32 + return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32; +# else + return (j * HZ_TO_USEC_NUM) / HZ_TO_USEC_DEN; +# endif +#endif } -EXPORT_SYMBOL(__jiffies_to_usecs); +EXPORT_SYMBOL(jiffies_to_usecs); /** * timespec_trunc - Truncate timespec to a granularity @@ -404,17 +427,76 @@ struct timeval ns_to_timeval(const s64 nsec) } EXPORT_SYMBOL(ns_to_timeval); -unsigned long __msecs_to_jiffies(const unsigned int m) +/* + * When we convert to jiffies then we interpret incoming values + * the following way: + * + * - negative values mean 'infinite timeout' (MAX_JIFFY_OFFSET) + * + * - 'too large' values [that would result in larger than + * MAX_JIFFY_OFFSET values] mean 'infinite timeout' too. + * + * - all other values are converted to jiffies by either multiplying + * the input value by a factor or dividing it with a factor + * + * We must also be careful about 32-bit overflows. + */ +unsigned long msecs_to_jiffies(const unsigned int m) { - return __inline_msecs_to_jiffies(m); + /* + * Negative value, means infinite timeout: + */ + if ((int)m < 0) + return MAX_JIFFY_OFFSET; + +#if HZ <= MSEC_PER_SEC && !(MSEC_PER_SEC % HZ) + /* + * HZ is equal to or smaller than 1000, and 1000 is a nice + * round multiple of HZ, divide with the factor between them, + * but round upwards: + */ + return (m + (MSEC_PER_SEC / HZ) - 1) / (MSEC_PER_SEC / HZ); +#elif HZ > MSEC_PER_SEC && !(HZ % MSEC_PER_SEC) + /* + * HZ is larger than 1000, and HZ is a nice round multiple of + * 1000 - simply multiply with the factor between them. + * + * But first make sure the multiplication result cannot + * overflow: + */ + if (m > jiffies_to_msecs(MAX_JIFFY_OFFSET)) + return MAX_JIFFY_OFFSET; + + return m * (HZ / MSEC_PER_SEC); +#else + /* + * Generic case - multiply, round and divide. But first + * check that if we are doing a net multiplication, that + * we wouldn't overflow: + */ + if (HZ > MSEC_PER_SEC && m > jiffies_to_msecs(MAX_JIFFY_OFFSET)) + return MAX_JIFFY_OFFSET; + + return (MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32) + >> MSEC_TO_HZ_SHR32; +#endif } -EXPORT_SYMBOL(__msecs_to_jiffies); +EXPORT_SYMBOL(msecs_to_jiffies); -unsigned long __usecs_to_jiffies(const unsigned int u) +unsigned long usecs_to_jiffies(const unsigned int u) { - return __inline_usecs_to_jiffies(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 (USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32) + >> USEC_TO_HZ_SHR32; +#endif } -EXPORT_SYMBOL(__usecs_to_jiffies); +EXPORT_SYMBOL(usecs_to_jiffies); /* * The TICK_NSEC - 1 rounds up the value to the next resolution. Note |