diff --git a/arch/x86/include/asm/vgtod.h b/arch/x86/include/asm/vgtod.h index dc27a69e5d2..3d61e204826 100644 --- a/arch/x86/include/asm/vgtod.h +++ b/arch/x86/include/asm/vgtod.h @@ -21,6 +21,7 @@ struct vsyscall_gtod_data { u32 shift; } clock; struct timespec wall_to_monotonic; + struct timespec wall_time_coarse; }; extern struct vsyscall_gtod_data __vsyscall_gtod_data __section_vsyscall_gtod_data; diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index 25ee06a80aa..cf53a78e2dc 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -87,6 +87,7 @@ void update_vsyscall(struct timespec *wall_time, struct clocksource *clock) vsyscall_gtod_data.wall_time_sec = wall_time->tv_sec; vsyscall_gtod_data.wall_time_nsec = wall_time->tv_nsec; vsyscall_gtod_data.wall_to_monotonic = wall_to_monotonic; + vsyscall_gtod_data.wall_time_coarse = __current_kernel_time(); write_sequnlock_irqrestore(&vsyscall_gtod_data.lock, flags); } diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c index 6a40b78b46a..ee55754cc3c 100644 --- a/arch/x86/vdso/vclock_gettime.c +++ b/arch/x86/vdso/vclock_gettime.c @@ -86,14 +86,47 @@ notrace static noinline int do_monotonic(struct timespec *ts) return 0; } +notrace static noinline int do_realtime_coarse(struct timespec *ts) +{ + unsigned long seq; + do { + seq = read_seqbegin(>od->lock); + ts->tv_sec = gtod->wall_time_coarse.tv_sec; + ts->tv_nsec = gtod->wall_time_coarse.tv_nsec; + } while (unlikely(read_seqretry(>od->lock, seq))); + return 0; +} + +notrace static noinline int do_monotonic_coarse(struct timespec *ts) +{ + unsigned long seq, ns, secs; + do { + seq = read_seqbegin(>od->lock); + secs = gtod->wall_time_coarse.tv_sec; + ns = gtod->wall_time_coarse.tv_nsec; + secs += gtod->wall_to_monotonic.tv_sec; + ns += gtod->wall_to_monotonic.tv_nsec; + } while (unlikely(read_seqretry(>od->lock, seq))); + vset_normalized_timespec(ts, secs, ns); + return 0; +} + notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts) { - if (likely(gtod->sysctl_enabled && gtod->clock.vread)) + if (likely(gtod->sysctl_enabled)) switch (clock) { case CLOCK_REALTIME: - return do_realtime(ts); + if (likely(gtod->clock.vread)) + return do_realtime(ts); + break; case CLOCK_MONOTONIC: - return do_monotonic(ts); + if (likely(gtod->clock.vread)) + return do_monotonic(ts); + break; + case CLOCK_REALTIME_COARSE: + return do_realtime_coarse(ts); + case CLOCK_MONOTONIC_COARSE: + return do_monotonic_coarse(ts); } return vdso_fallback_gettime(clock, ts); } diff --git a/include/linux/time.h b/include/linux/time.h index f505988398e..256232f7e5e 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -110,6 +110,8 @@ extern int timekeeping_suspended; unsigned long get_seconds(void); struct timespec current_kernel_time(void); +struct timespec __current_kernel_time(void); /* does not hold xtime_lock */ +struct timespec get_monotonic_coarse(void); #define CURRENT_TIME (current_kernel_time()) #define CURRENT_TIME_SEC ((struct timespec) { get_seconds(), 0 }) @@ -243,6 +245,8 @@ struct itimerval { #define CLOCK_PROCESS_CPUTIME_ID 2 #define CLOCK_THREAD_CPUTIME_ID 3 #define CLOCK_MONOTONIC_RAW 4 +#define CLOCK_REALTIME_COARSE 5 +#define CLOCK_MONOTONIC_COARSE 6 /* * The IDs of various hardware clocks: diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c index d089d052c4a..495440779ce 100644 --- a/kernel/posix-timers.c +++ b/kernel/posix-timers.c @@ -242,6 +242,25 @@ static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp) return 0; } + +static int posix_get_realtime_coarse(clockid_t which_clock, struct timespec *tp) +{ + *tp = current_kernel_time(); + return 0; +} + +static int posix_get_monotonic_coarse(clockid_t which_clock, + struct timespec *tp) +{ + *tp = get_monotonic_coarse(); + return 0; +} + +int posix_get_coarse_res(const clockid_t which_clock, struct timespec *tp) +{ + *tp = ktime_to_timespec(KTIME_LOW_RES); + return 0; +} /* * Initialize everything, well, just everything in Posix clocks/timers ;) */ @@ -262,10 +281,26 @@ static __init int init_posix_timers(void) .timer_create = no_timer_create, .nsleep = no_nsleep, }; + struct k_clock clock_realtime_coarse = { + .clock_getres = posix_get_coarse_res, + .clock_get = posix_get_realtime_coarse, + .clock_set = do_posix_clock_nosettime, + .timer_create = no_timer_create, + .nsleep = no_nsleep, + }; + struct k_clock clock_monotonic_coarse = { + .clock_getres = posix_get_coarse_res, + .clock_get = posix_get_monotonic_coarse, + .clock_set = do_posix_clock_nosettime, + .timer_create = no_timer_create, + .nsleep = no_nsleep, + }; register_posix_clock(CLOCK_REALTIME, &clock_realtime); register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic); register_posix_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw); + register_posix_clock(CLOCK_REALTIME_COARSE, &clock_realtime_coarse); + register_posix_clock(CLOCK_MONOTONIC_COARSE, &clock_monotonic_coarse); posix_timers_cache = kmem_cache_create("posix_timers_cache", sizeof (struct k_itimer), 0, SLAB_PANIC, diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 15e06defca5..03cbeb34d14 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -847,6 +847,10 @@ unsigned long get_seconds(void) } EXPORT_SYMBOL(get_seconds); +struct timespec __current_kernel_time(void) +{ + return xtime_cache; +} struct timespec current_kernel_time(void) { @@ -862,3 +866,20 @@ struct timespec current_kernel_time(void) return now; } EXPORT_SYMBOL(current_kernel_time); + +struct timespec get_monotonic_coarse(void) +{ + struct timespec now, mono; + unsigned long seq; + + do { + seq = read_seqbegin(&xtime_lock); + + now = xtime_cache; + mono = wall_to_monotonic; + } while (read_seqretry(&xtime_lock, seq)); + + set_normalized_timespec(&now, now.tv_sec + mono.tv_sec, + now.tv_nsec + mono.tv_nsec); + return now; +}