diff options
Diffstat (limited to 'kernel/time.c')
| -rw-r--r-- | kernel/time.c | 63 |
1 files changed, 29 insertions, 34 deletions
diff --git a/kernel/time.c b/kernel/time.c index 35d373a98782..6a08660b4fac 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -35,6 +35,8 @@ #include <linux/syscalls.h> #include <linux/security.h> #include <linux/fs.h> +#include <linux/slab.h> +#include <linux/math64.h> #include <asm/uaccess.h> #include <asm/unistd.h> @@ -244,7 +246,7 @@ unsigned int inline jiffies_to_msecs(const unsigned long j) return (j + (HZ / MSEC_PER_SEC) - 1)/(HZ / MSEC_PER_SEC); #else # if BITS_PER_LONG == 32 - return ((u64)HZ_TO_MSEC_MUL32 * j) >> HZ_TO_MSEC_SHR32; + return (HZ_TO_MSEC_MUL32 * j) >> HZ_TO_MSEC_SHR32; # else return (j * HZ_TO_MSEC_NUM) / HZ_TO_MSEC_DEN; # endif @@ -260,7 +262,7 @@ unsigned int inline jiffies_to_usecs(const unsigned long j) return (j + (HZ / USEC_PER_SEC) - 1)/(HZ / USEC_PER_SEC); #else # if BITS_PER_LONG == 32 - return ((u64)HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32; + return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32; # else return (j * HZ_TO_USEC_NUM) / HZ_TO_USEC_DEN; # endif @@ -390,13 +392,17 @@ EXPORT_SYMBOL(set_normalized_timespec); struct timespec ns_to_timespec(const s64 nsec) { struct timespec ts; + s32 rem; if (!nsec) return (struct timespec) {0, 0}; - ts.tv_sec = div_long_long_rem_signed(nsec, NSEC_PER_SEC, &ts.tv_nsec); - if (unlikely(nsec < 0)) - set_normalized_timespec(&ts, ts.tv_sec, ts.tv_nsec); + ts.tv_sec = div_s64_rem(nsec, NSEC_PER_SEC, &rem); + if (unlikely(rem < 0)) { + ts.tv_sec--; + rem += NSEC_PER_SEC; + } + ts.tv_nsec = rem; return ts; } @@ -470,7 +476,7 @@ unsigned long msecs_to_jiffies(const unsigned int m) if (HZ > MSEC_PER_SEC && m > jiffies_to_msecs(MAX_JIFFY_OFFSET)) return MAX_JIFFY_OFFSET; - return ((u64)MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32) + return (MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32) >> MSEC_TO_HZ_SHR32; #endif } @@ -485,7 +491,7 @@ unsigned long usecs_to_jiffies(const unsigned int u) #elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC) return u * (HZ / USEC_PER_SEC); #else - return ((u64)USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32) + return (USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32) >> USEC_TO_HZ_SHR32; #endif } @@ -526,8 +532,10 @@ 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); + u32 rem; + value->tv_sec = div_u64_rem((u64)jiffies * TICK_NSEC, + NSEC_PER_SEC, &rem); + value->tv_nsec = rem; } EXPORT_SYMBOL(jiffies_to_timespec); @@ -565,12 +573,11 @@ 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; + u32 rem; - value->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &tv_usec); - tv_usec /= NSEC_PER_USEC; - value->tv_usec = tv_usec; + value->tv_sec = div_u64_rem((u64)jiffies * TICK_NSEC, + NSEC_PER_SEC, &rem); + value->tv_usec = rem / NSEC_PER_USEC; } EXPORT_SYMBOL(jiffies_to_timeval); @@ -586,9 +593,7 @@ clock_t jiffies_to_clock_t(long x) return x / (HZ / USER_HZ); # endif #else - u64 tmp = (u64)x * TICK_NSEC; - do_div(tmp, (NSEC_PER_SEC / USER_HZ)); - return (long)tmp; + return div_u64((u64)x * TICK_NSEC, NSEC_PER_SEC / USER_HZ); #endif } EXPORT_SYMBOL(jiffies_to_clock_t); @@ -600,16 +605,12 @@ unsigned long clock_t_to_jiffies(unsigned long x) 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; + return div_u64((u64)x * HZ, USER_HZ); #endif } EXPORT_SYMBOL(clock_t_to_jiffies); @@ -618,10 +619,9 @@ u64 jiffies_64_to_clock_t(u64 x) { #if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 # if HZ < USER_HZ - x *= USER_HZ; - do_div(x, HZ); + x = div_u64(x * USER_HZ, HZ); # elif HZ > USER_HZ - do_div(x, HZ / USER_HZ); + x = div_u64(x, HZ / USER_HZ); # else /* Nothing to do */ # endif @@ -631,8 +631,7 @@ u64 jiffies_64_to_clock_t(u64 x) * 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)); + x = div_u64(x * TICK_NSEC, (NSEC_PER_SEC / USER_HZ)); #endif return x; } @@ -641,21 +640,17 @@ EXPORT_SYMBOL(jiffies_64_to_clock_t); u64 nsec_to_clock_t(u64 x) { #if (NSEC_PER_SEC % USER_HZ) == 0 - do_div(x, (NSEC_PER_SEC / USER_HZ)); + return div_u64(x, NSEC_PER_SEC / USER_HZ); #elif (USER_HZ % 512) == 0 - x *= USER_HZ/512; - do_div(x, (NSEC_PER_SEC / 512)); + return div_u64(x * USER_HZ / 512, 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)); + return div_u64(x * 9, (9ull * NSEC_PER_SEC + (USER_HZ / 2)) / USER_HZ); #endif - return x; } #if (BITS_PER_LONG < 64) |
