From 4a0e637738f06673725792d74eed67f8779b62c7 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 16 Jul 2014 21:05:13 +0000 Subject: clocksource: Get rid of cycle_last cycle_last was added to the clocksource to support the TSC validation. We moved that to the core code, so we can get rid of the extra copy. Signed-off-by: Thomas Gleixner Signed-off-by: John Stultz --- arch/arm64/kernel/vdso.c | 2 +- arch/ia64/kernel/time.c | 4 ++-- arch/powerpc/kernel/time.c | 4 ++-- arch/s390/kernel/time.c | 2 +- arch/tile/kernel/time.c | 2 +- arch/x86/kernel/vsyscall_gtod.c | 2 +- arch/x86/kvm/x86.c | 2 +- include/linux/clocksource.h | 2 -- include/linux/timekeeper_internal.h | 7 ++++--- kernel/time/timekeeping.c | 23 +++++++++++------------ 10 files changed, 24 insertions(+), 26 deletions(-) diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 50384fec56c4..574672f001f7 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -224,7 +224,7 @@ void update_vsyscall(struct timekeeper *tk) vdso_data->wtm_clock_nsec = tk->wall_to_monotonic.tv_nsec; if (!use_syscall) { - vdso_data->cs_cycle_last = tk->clock->cycle_last; + vdso_data->cs_cycle_last = tk->cycle_last; vdso_data->xtime_clock_sec = tk->xtime_sec; vdso_data->xtime_clock_nsec = tk->xtime_nsec; vdso_data->cs_mult = tk->mult; diff --git a/arch/ia64/kernel/time.c b/arch/ia64/kernel/time.c index 71c52bc7c28d..11dc42da7daf 100644 --- a/arch/ia64/kernel/time.c +++ b/arch/ia64/kernel/time.c @@ -441,7 +441,7 @@ void update_vsyscall_tz(void) } void update_vsyscall_old(struct timespec *wall, struct timespec *wtm, - struct clocksource *c, u32 mult) + struct clocksource *c, u32 mult, cycles_t cycle_last) { write_seqcount_begin(&fsyscall_gtod_data.seq); @@ -450,7 +450,7 @@ void update_vsyscall_old(struct timespec *wall, struct timespec *wtm, fsyscall_gtod_data.clk_mult = mult; fsyscall_gtod_data.clk_shift = c->shift; fsyscall_gtod_data.clk_fsys_mmio = c->archdata.fsys_mmio; - fsyscall_gtod_data.clk_cycle_last = c->cycle_last; + fsyscall_gtod_data.clk_cycle_last = cycle_last; /* copy kernel time structures */ fsyscall_gtod_data.wall_time.tv_sec = wall->tv_sec; diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 9fff9cdcc519..368ab374d33c 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -741,7 +741,7 @@ static cycle_t timebase_read(struct clocksource *cs) } void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm, - struct clocksource *clock, u32 mult) + struct clocksource *clock, u32 mult, cycle_t cycle_last) { u64 new_tb_to_xs, new_stamp_xsec; u32 frac_sec; @@ -774,7 +774,7 @@ void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm, * We expect the caller to have done the first increment of * vdso_data->tb_update_count already. */ - vdso_data->tb_orig_stamp = clock->cycle_last; + vdso_data->tb_orig_stamp = cycle_last; vdso_data->stamp_xsec = new_stamp_xsec; vdso_data->tb_to_xs = new_tb_to_xs; vdso_data->wtom_clock_sec = wtm->tv_sec; diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index 0931b110c826..97950f392613 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -220,7 +220,7 @@ void update_vsyscall(struct timekeeper *tk) /* Make userspace gettimeofday spin until we're done. */ ++vdso_data->tb_update_count; smp_wmb(); - vdso_data->xtime_tod_stamp = tk->clock->cycle_last; + vdso_data->xtime_tod_stamp = tk->cycle_last; vdso_data->xtime_clock_sec = tk->xtime_sec; vdso_data->xtime_clock_nsec = tk->xtime_nsec; vdso_data->wtom_clock_sec = diff --git a/arch/tile/kernel/time.c b/arch/tile/kernel/time.c index ae70155c2f16..d22d5bfc1e4e 100644 --- a/arch/tile/kernel/time.c +++ b/arch/tile/kernel/time.c @@ -269,7 +269,7 @@ void update_vsyscall(struct timekeeper *tk) /* Userspace gettimeofday will spin while this value is odd. */ ++vdso_data->tb_update_count; smp_wmb(); - vdso_data->xtime_tod_stamp = clock->cycle_last; + vdso_data->xtime_tod_stamp = tk->cycle_last; vdso_data->xtime_clock_sec = tk->xtime_sec; vdso_data->xtime_clock_nsec = tk->xtime_nsec; vdso_data->wtom_clock_sec = wtm->tv_sec; diff --git a/arch/x86/kernel/vsyscall_gtod.c b/arch/x86/kernel/vsyscall_gtod.c index 9531fbb123ba..c3cb3c144591 100644 --- a/arch/x86/kernel/vsyscall_gtod.c +++ b/arch/x86/kernel/vsyscall_gtod.c @@ -32,7 +32,7 @@ void update_vsyscall(struct timekeeper *tk) /* copy vsyscall data */ vdata->vclock_mode = tk->clock->archdata.vclock_mode; - vdata->cycle_last = tk->clock->cycle_last; + vdata->cycle_last = tk->cycle_last; vdata->mask = tk->clock->mask; vdata->mult = tk->mult; vdata->shift = tk->shift; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 63832f5110b6..7b25125f3f42 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1001,7 +1001,7 @@ static void update_pvclock_gtod(struct timekeeper *tk) /* copy pvclock gtod data */ vdata->clock.vclock_mode = tk->clock->archdata.vclock_mode; - vdata->clock.cycle_last = tk->clock->cycle_last; + vdata->clock.cycle_last = tk->cycle_last; vdata->clock.mask = tk->clock->mask; vdata->clock.mult = tk->mult; vdata->clock.shift = tk->shift; diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index a16b497d5159..653f0e2b6ca9 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -162,7 +162,6 @@ extern u64 timecounter_cyc2time(struct timecounter *tc, * @archdata: arch-specific data * @suspend: suspend function for the clocksource, if necessary * @resume: resume function for the clocksource, if necessary - * @cycle_last: most recent cycle counter value seen by ::read() * @owner: module reference, must be set by clocksource in modules */ struct clocksource { @@ -171,7 +170,6 @@ struct clocksource { * clocksource itself is cacheline aligned. */ cycle_t (*read)(struct clocksource *cs); - cycle_t cycle_last; cycle_t mask; u32 mult; u32 shift; diff --git a/include/linux/timekeeper_internal.h b/include/linux/timekeeper_internal.h index 2e20275a7083..cb88096222c0 100644 --- a/include/linux/timekeeper_internal.h +++ b/include/linux/timekeeper_internal.h @@ -29,6 +29,8 @@ struct timekeeper { /* Current clocksource used for timekeeping. */ struct clocksource *clock; + /* Last cycle value */ + cycle_t cycle_last; /* NTP adjusted clock multiplier */ u32 mult; /* The shift value of the current clocksource. */ @@ -62,8 +64,6 @@ struct timekeeper { /* Number of clock cycles in one NTP interval. */ cycle_t cycle_interval; - /* Last cycle value (also stored in clock->cycle_last) */ - cycle_t cycle_last; /* Number of clock shifted nano seconds in one NTP interval. */ u64 xtime_interval; /* shifted nano seconds left over when rounding cycle_interval */ @@ -91,7 +91,8 @@ extern void update_vsyscall_tz(void); #elif defined(CONFIG_GENERIC_TIME_VSYSCALL_OLD) extern void update_vsyscall_old(struct timespec *ts, struct timespec *wtm, - struct clocksource *c, u32 mult); + struct clocksource *c, u32 mult, + cycles_t cycle_last); extern void update_vsyscall_tz(void); #else diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 531805013786..4e748c404749 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -121,7 +121,7 @@ static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock) old_clock = tk->clock; tk->clock = clock; - tk->cycle_last = clock->cycle_last = clock->read(clock); + tk->cycle_last = clock->read(clock); /* Do the ns -> cycle conversion first, using original mult */ tmp = NTP_INTERVAL_LENGTH; @@ -182,7 +182,7 @@ static inline s64 timekeeping_get_ns(struct timekeeper *tk) cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ - delta = clocksource_delta(cycle_now, clock->cycle_last, clock->mask); + delta = clocksource_delta(cycle_now, tk->cycle_last, clock->mask); nsec = delta * tk->mult + tk->xtime_nsec; nsec >>= tk->shift; @@ -202,7 +202,7 @@ static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk) cycle_now = clock->read(clock); /* calculate the delta since the last update_wall_time: */ - delta = clocksource_delta(cycle_now, clock->cycle_last, clock->mask); + delta = clocksource_delta(cycle_now, tk->cycle_last, clock->mask); /* convert delta to nanoseconds. */ nsec = clocksource_cyc2ns(delta, clock->mult, clock->shift); @@ -218,7 +218,8 @@ static inline void update_vsyscall(struct timekeeper *tk) struct timespec xt; xt = tk_xtime(tk); - update_vsyscall_old(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult); + update_vsyscall_old(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult, + tk->cycle_last); } static inline void old_vsyscall_fixup(struct timekeeper *tk) @@ -342,8 +343,8 @@ static void timekeeping_forward_now(struct timekeeper *tk) clock = tk->clock; cycle_now = clock->read(clock); - delta = clocksource_delta(cycle_now, clock->cycle_last, clock->mask); - tk->cycle_last = clock->cycle_last = cycle_now; + delta = clocksource_delta(cycle_now, tk->cycle_last, clock->mask); + tk->cycle_last = cycle_now; tk->xtime_nsec += delta * tk->mult; @@ -1020,13 +1021,13 @@ static void timekeeping_resume(void) */ cycle_now = clock->read(clock); if ((clock->flags & CLOCK_SOURCE_SUSPEND_NONSTOP) && - cycle_now > clock->cycle_last) { + cycle_now > tk->cycle_last) { u64 num, max = ULLONG_MAX; u32 mult = clock->mult; u32 shift = clock->shift; s64 nsec = 0; - cycle_delta = clocksource_delta(cycle_now, clock->cycle_last, + cycle_delta = clocksource_delta(cycle_now, tk->cycle_last, clock->mask); /* @@ -1053,7 +1054,7 @@ static void timekeeping_resume(void) __timekeeping_inject_sleeptime(tk, &ts_delta); /* Re-base the last cycle value */ - tk->cycle_last = clock->cycle_last = cycle_now; + tk->cycle_last = cycle_now; tk->ntp_error = 0; timekeeping_suspended = 0; timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET); @@ -1433,7 +1434,7 @@ void update_wall_time(void) #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET offset = real_tk->cycle_interval; #else - offset = clocksource_delta(clock->read(clock), clock->cycle_last, + offset = clocksource_delta(clock->read(clock), tk->cycle_last, clock->mask); #endif @@ -1477,8 +1478,6 @@ void update_wall_time(void) clock_set |= accumulate_nsecs_to_secs(tk); write_seqcount_begin(&tk_core.seq); - /* Update clock->cycle_last with the new value */ - clock->cycle_last = tk->cycle_last; /* * Update the real timekeeper. * -- cgit v1.2.3