diff options
Diffstat (limited to 'arch/powerpc/kernel/time.c')
| -rw-r--r-- | arch/powerpc/kernel/time.c | 61 |
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) } EXPORT_SYMBOL(udelay); -static inline void update_gtod(u64 new_tb_stamp, u64 new_stamp_xsec, - u64 new_tb_to_xs) -{ - /* - * tb_update_count is used to allow the userspace gettimeofday code - * to assure itself that it sees a consistent view of the tb_to_xs and - * stamp_xsec variables. It reads the tb_update_count, then reads - * tb_to_xs and stamp_xsec and then reads tb_update_count again. If - * the two values of tb_update_count match and are even then the - * tb_to_xs and stamp_xsec values are consistent. If not, then it - * loops back and reads them again until this criteria is met. - * We expect the caller to have done the first increment of - * vdso_data->tb_update_count already. - */ - vdso_data->tb_orig_stamp = new_tb_stamp; - vdso_data->stamp_xsec = new_stamp_xsec; - vdso_data->tb_to_xs = new_tb_to_xs; - vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec; - vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec; - vdso_data->stamp_xtime = xtime; - smp_wmb(); - ++(vdso_data->tb_update_count); -} - #ifdef CONFIG_SMP unsigned long profile_pc(struct pt_regs *regs) { @@ -873,10 +849,37 @@ static cycle_t timebase_read(struct clocksource *cs) return (cycle_t)get_tb(); } +static inline void update_gtod(u64 new_tb_stamp, u64 new_stamp_xsec, + u64 new_tb_to_xs, struct timespec *now, + u32 frac_sec) +{ + /* + * tb_update_count is used to allow the userspace gettimeofday code + * to assure itself that it sees a consistent view of the tb_to_xs and + * stamp_xsec variables. It reads the tb_update_count, then reads + * tb_to_xs and stamp_xsec and then reads tb_update_count again. If + * the two values of tb_update_count match and are even then the + * tb_to_xs and stamp_xsec values are consistent. If not, then it + * loops back and reads them again until this criteria is met. + * We expect the caller to have done the first increment of + * vdso_data->tb_update_count already. + */ + vdso_data->tb_orig_stamp = new_tb_stamp; + vdso_data->stamp_xsec = new_stamp_xsec; + vdso_data->tb_to_xs = new_tb_to_xs; + vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec; + vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec; + vdso_data->stamp_xtime = *now; + vdso_data->stamp_sec_fraction = frac_sec; + smp_wmb(); + ++(vdso_data->tb_update_count); +} + void update_vsyscall(struct timespec *wall_time, struct clocksource *clock, u32 mult) { u64 t2x, stamp_xsec; + u32 frac_sec; if (clock != &clocksource_timebase) return; @@ -888,10 +891,14 @@ void update_vsyscall(struct timespec *wall_time, struct clocksource *clock, /* XXX this assumes clock->shift == 22 */ /* 4611686018 ~= 2^(20+64-22) / 1e9 */ t2x = (u64) mult * 4611686018ULL; - stamp_xsec = (u64) xtime.tv_nsec * XSEC_PER_SEC; + stamp_xsec = (u64) wall_time->tv_nsec * XSEC_PER_SEC; do_div(stamp_xsec, 1000000000); - stamp_xsec += (u64) xtime.tv_sec * XSEC_PER_SEC; - update_gtod(clock->cycle_last, stamp_xsec, t2x); + stamp_xsec += (u64) wall_time->tv_sec * XSEC_PER_SEC; + + BUG_ON(wall_time->tv_nsec >= NSEC_PER_SEC); + /* this is tv_nsec / 1e9 as a 0.32 fraction */ + frac_sec = ((u64) wall_time->tv_nsec * 18446744073ULL) >> 32; + update_gtod(clock->cycle_last, stamp_xsec, t2x, wall_time, frac_sec); } void update_vsyscall_tz(void) |