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-rw-r--r--arch/powerpc/kernel/time.c61
1 files changed, 34 insertions, 27 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 0441bbdadbd1..5adebaf47f13 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -423,30 +423,6 @@ void udelay(unsigned long usecs)
423} 423}
424EXPORT_SYMBOL(udelay); 424EXPORT_SYMBOL(udelay);
425 425
426static inline void update_gtod(u64 new_tb_stamp, u64 new_stamp_xsec,
427 u64 new_tb_to_xs)
428{
429 /*
430 * tb_update_count is used to allow the userspace gettimeofday code
431 * to assure itself that it sees a consistent view of the tb_to_xs and
432 * stamp_xsec variables. It reads the tb_update_count, then reads
433 * tb_to_xs and stamp_xsec and then reads tb_update_count again. If
434 * the two values of tb_update_count match and are even then the
435 * tb_to_xs and stamp_xsec values are consistent. If not, then it
436 * loops back and reads them again until this criteria is met.
437 * We expect the caller to have done the first increment of
438 * vdso_data->tb_update_count already.
439 */
440 vdso_data->tb_orig_stamp = new_tb_stamp;
441 vdso_data->stamp_xsec = new_stamp_xsec;
442 vdso_data->tb_to_xs = new_tb_to_xs;
443 vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec;
444 vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec;
445 vdso_data->stamp_xtime = xtime;
446 smp_wmb();
447 ++(vdso_data->tb_update_count);
448}
449
450#ifdef CONFIG_SMP 426#ifdef CONFIG_SMP
451unsigned long profile_pc(struct pt_regs *regs) 427unsigned long profile_pc(struct pt_regs *regs)
452{ 428{
@@ -873,10 +849,37 @@ static cycle_t timebase_read(struct clocksource *cs)
873 return (cycle_t)get_tb(); 849 return (cycle_t)get_tb();
874} 850}
875 851
852static inline void update_gtod(u64 new_tb_stamp, u64 new_stamp_xsec,
853 u64 new_tb_to_xs, struct timespec *now,
854 u32 frac_sec)
855{
856 /*
857 * tb_update_count is used to allow the userspace gettimeofday code
858 * to assure itself that it sees a consistent view of the tb_to_xs and
859 * stamp_xsec variables. It reads the tb_update_count, then reads
860 * tb_to_xs and stamp_xsec and then reads tb_update_count again. If
861 * the two values of tb_update_count match and are even then the
862 * tb_to_xs and stamp_xsec values are consistent. If not, then it
863 * loops back and reads them again until this criteria is met.
864 * We expect the caller to have done the first increment of
865 * vdso_data->tb_update_count already.
866 */
867 vdso_data->tb_orig_stamp = new_tb_stamp;
868 vdso_data->stamp_xsec = new_stamp_xsec;
869 vdso_data->tb_to_xs = new_tb_to_xs;
870 vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec;
871 vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec;
872 vdso_data->stamp_xtime = *now;
873 vdso_data->stamp_sec_fraction = frac_sec;
874 smp_wmb();
875 ++(vdso_data->tb_update_count);
876}
877
876void update_vsyscall(struct timespec *wall_time, struct clocksource *clock, 878void update_vsyscall(struct timespec *wall_time, struct clocksource *clock,
877 u32 mult) 879 u32 mult)
878{ 880{
879 u64 t2x, stamp_xsec; 881 u64 t2x, stamp_xsec;
882 u32 frac_sec;
880 883
881 if (clock != &clocksource_timebase) 884 if (clock != &clocksource_timebase)
882 return; 885 return;
@@ -888,10 +891,14 @@ void update_vsyscall(struct timespec *wall_time, struct clocksource *clock,
888 /* XXX this assumes clock->shift == 22 */ 891 /* XXX this assumes clock->shift == 22 */
889 /* 4611686018 ~= 2^(20+64-22) / 1e9 */ 892 /* 4611686018 ~= 2^(20+64-22) / 1e9 */
890 t2x = (u64) mult * 4611686018ULL; 893 t2x = (u64) mult * 4611686018ULL;
891 stamp_xsec = (u64) xtime.tv_nsec * XSEC_PER_SEC; 894 stamp_xsec = (u64) wall_time->tv_nsec * XSEC_PER_SEC;
892 do_div(stamp_xsec, 1000000000); 895 do_div(stamp_xsec, 1000000000);
893 stamp_xsec += (u64) xtime.tv_sec * XSEC_PER_SEC; 896 stamp_xsec += (u64) wall_time->tv_sec * XSEC_PER_SEC;
894 update_gtod(clock->cycle_last, stamp_xsec, t2x); 897
898 BUG_ON(wall_time->tv_nsec >= NSEC_PER_SEC);
899 /* this is tv_nsec / 1e9 as a 0.32 fraction */
900 frac_sec = ((u64) wall_time->tv_nsec * 18446744073ULL) >> 32;
901 update_gtod(clock->cycle_last, stamp_xsec, t2x, wall_time, frac_sec);
895} 902}
896 903
897void update_vsyscall_tz(void) 904void update_vsyscall_tz(void)