From 72199320d49dbafa1a99f94f1cd60dc90035c154 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 1 Mar 2018 17:33:32 +0100 Subject: timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock The planned change to unify the behaviour of the MONOTONIC and BOOTTIME clocks vs. suspend removes the ability to retrieve the active non-suspended time of a system. Provide a new CLOCK_MONOTONIC_ACTIVE clock which returns the active non-suspended time of the system via clock_gettime(). This preserves the old behaviour of CLOCK_MONOTONIC before the BOOTTIME/MONOTONIC unification. This new clock also allows applications to detect programmatically that the MONOTONIC and BOOTTIME clocks are identical. Signed-off-by: Thomas Gleixner Cc: Dmitry Torokhov Cc: John Stultz Cc: Jonathan Corbet Cc: Kevin Easton Cc: Linus Torvalds Cc: Mark Salyzyn Cc: Michael Kerrisk Cc: Peter Zijlstra Cc: Petr Mladek Cc: Prarit Bhargava Cc: Sergey Senozhatsky Cc: Steven Rostedt Link: http://lkml.kernel.org/r/20180301165149.965235774@linutronix.de Signed-off-by: Ingo Molnar --- include/uapi/linux/time.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/uapi/linux/time.h') diff --git a/include/uapi/linux/time.h b/include/uapi/linux/time.h index 53f8dd84beb5..61a187df8da2 100644 --- a/include/uapi/linux/time.h +++ b/include/uapi/linux/time.h @@ -61,6 +61,7 @@ struct itimerval { */ #define CLOCK_SGI_CYCLE 10 #define CLOCK_TAI 11 +#define CLOCK_MONOTONIC_ACTIVE 12 #define MAX_CLOCKS 16 #define CLOCKS_MASK (CLOCK_REALTIME | CLOCK_MONOTONIC) -- cgit v1.2.3 From a84d1169164b274f13b97a23ff235c000efe3b49 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 15 Mar 2018 17:12:40 +0100 Subject: y2038: Introduce struct __kernel_old_timeval Dealing with 'struct timeval' users in the y2038 series is a bit tricky: We have two definitions of timeval that are visible to user space, one comes from glibc (or some other C library), the other comes from linux/time.h. The kernel copy is what we want to be used for a number of structures defined by the kernel itself, e.g. elf_prstatus (used it core dumps), sysinfo and rusage (used in system calls). These generally tend to be used for passing time intervals rather than absolute (epoch-based) times, so they do not suffer from the y2038 overflow. Some of them could be changed to use 64-bit timestamps by creating new system calls, others like the core files cannot easily be changed. An application using these interfaces likely also uses gettimeofday() or other interfaces that use absolute times, and pass 'struct timeval' pointers directly into kernel interfaces, so glibc must redefine their timeval based on a 64-bit time_t when they introduce their y2038-safe interfaces. The only reasonable way forward I see is to remove the 'timeval' definion from the kernel's uapi headers, and change the interfaces that we do not want to (or cannot) duplicate for 64-bit times to use a new __kernel_old_timeval definition instead. This type should be avoided for all new interfaces (those can use 64-bit nanoseconds, or the 64-bit version of timespec instead), and should be used with great care when converting existing interfaces from timeval, to be sure they don't suffer from the y2038 overflow, and only with consensus for the particular user that using __kernel_old_timeval is better than moving to a 64-bit based interface. The structure name is intentionally chosen to not conflict with user space types, and to be ugly enough to discourage its use. Note that ioctl based interfaces that pass a bare 'timeval' pointer cannot change to '__kernel_old_timeval' because the user space source code refers to 'timeval' instead, and we don't want to modify the user space sources if possible. However, any application that relies on a structure to contain an embedded 'timeval' (e.g. by passing a pointer to the member into a function call that expects a timeval pointer) is broken when that structure gets converted to __kernel_old_timeval. I don't see any way around that, and we have to rely on the compiler to produce a warning or compile failure that will alert users when they recompile their sources against a new libc. Signed-off-by: Arnd Bergmann Signed-off-by: Thomas Gleixner Cc: Stephen Boyd Cc: John Stultz Cc: Al Viro Link: https://lkml.kernel.org/r/20180315161739.576085-1-arnd@arndb.de --- include/linux/time32.h | 1 + include/uapi/linux/time.h | 12 ++++++++++++ kernel/time/time.c | 12 ++++++++++++ 3 files changed, 25 insertions(+) (limited to 'include/uapi/linux/time.h') diff --git a/include/linux/time32.h b/include/linux/time32.h index 65b1de25198d..d2bcd4377b56 100644 --- a/include/linux/time32.h +++ b/include/linux/time32.h @@ -217,5 +217,6 @@ static inline s64 timeval_to_ns(const struct timeval *tv) * Returns the timeval representation of the nsec parameter. */ extern struct timeval ns_to_timeval(const s64 nsec); +extern struct __kernel_old_timeval ns_to_kernel_old_timeval(s64 nsec); #endif diff --git a/include/uapi/linux/time.h b/include/uapi/linux/time.h index 61a187df8da2..16a296612ba4 100644 --- a/include/uapi/linux/time.h +++ b/include/uapi/linux/time.h @@ -42,6 +42,18 @@ struct itimerval { struct timeval it_value; /* current value */ }; +/* + * legacy timeval structure, only embedded in structures that + * traditionally used 'timeval' to pass time intervals (not absolute + * times). Do not add new users. If user space fails to compile + * here, this is probably because it is not y2038 safe and needs to + * be changed to use another interface. + */ +struct __kernel_old_timeval { + __kernel_long_t tv_sec; + __kernel_long_t tv_usec; +}; + /* * The IDs of the various system clocks (for POSIX.1b interval timers): */ diff --git a/kernel/time/time.c b/kernel/time/time.c index bd4e6c7dd689..3044d48ebe56 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -488,6 +488,18 @@ struct timeval ns_to_timeval(const s64 nsec) } EXPORT_SYMBOL(ns_to_timeval); +struct __kernel_old_timeval ns_to_kernel_old_timeval(const s64 nsec) +{ + struct timespec64 ts = ns_to_timespec64(nsec); + struct __kernel_old_timeval tv; + + tv.tv_sec = ts.tv_sec; + tv.tv_usec = (suseconds_t)ts.tv_nsec / 1000; + + return tv; +} +EXPORT_SYMBOL(ns_to_kernel_old_timeval); + /** * set_normalized_timespec - set timespec sec and nsec parts and normalize * -- cgit v1.2.3 From a3ed0e4393d6885b4af7ce84b437dc696490a530 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 25 Apr 2018 15:33:38 +0200 Subject: Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME Revert commits 92af4dcb4e1c ("tracing: Unify the "boot" and "mono" tracing clocks") 127bfa5f4342 ("hrtimer: Unify MONOTONIC and BOOTTIME clock behavior") 7250a4047aa6 ("posix-timers: Unify MONOTONIC and BOOTTIME clock behavior") d6c7270e913d ("timekeeping: Remove boot time specific code") f2d6fdbfd238 ("Input: Evdev - unify MONOTONIC and BOOTTIME clock behavior") d6ed449afdb3 ("timekeeping: Make the MONOTONIC clock behave like the BOOTTIME clock") 72199320d49d ("timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock") As stated in the pull request for the unification of CLOCK_MONOTONIC and CLOCK_BOOTTIME, it was clear that we might have to revert the change. As reported by several folks systemd and other applications rely on the documented behaviour of CLOCK_MONOTONIC on Linux and break with the above changes. After resume daemons time out and other timeout related issues are observed. Rafael compiled this list: * systemd kills daemons on resume, after >WatchdogSec seconds of suspending (Genki Sky). [Verified that that's because systemd uses CLOCK_MONOTONIC and expects it to not include the suspend time.] * systemd-journald misbehaves after resume: systemd-journald[7266]: File /var/log/journal/016627c3c4784cd4812d4b7e96a34226/system.journal corrupted or uncleanly shut down, renaming and replacing. (Mike Galbraith). * NetworkManager reports "networking disabled" and networking is broken after resume 50% of the time (Pavel). [May be because of systemd.] * MATE desktop dims the display and starts the screensaver right after system resume (Pavel). * Full system hang during resume (me). [May be due to systemd or NM or both.] That happens on debian and open suse systems. It's sad, that these problems were neither catched in -next nor by those folks who expressed interest in this change. Reported-by: Rafael J. Wysocki Reported-by: Genki Sky , Reported-by: Pavel Machek Signed-off-by: Thomas Gleixner Cc: Dmitry Torokhov Cc: John Stultz Cc: Jonathan Corbet Cc: Kevin Easton Cc: Linus Torvalds Cc: Mark Salyzyn Cc: Michael Kerrisk Cc: Peter Zijlstra Cc: Petr Mladek Cc: Prarit Bhargava Cc: Sergey Senozhatsky Cc: Steven Rostedt --- Documentation/trace/ftrace.rst | 14 +++++-- drivers/input/evdev.c | 7 +++- include/linux/hrtimer.h | 2 + include/linux/timekeeper_internal.h | 2 - include/linux/timekeeping.h | 37 ++++++++++++------ include/uapi/linux/time.h | 1 - kernel/time/hrtimer.c | 16 +++++++- kernel/time/posix-stubs.c | 2 - kernel/time/posix-timers.c | 26 ++++++++----- kernel/time/tick-common.c | 15 ------- kernel/time/tick-internal.h | 6 --- kernel/time/tick-sched.c | 9 ----- kernel/time/timekeeping.c | 78 ++++++++++++++++++------------------- kernel/time/timekeeping.h | 1 + kernel/trace/trace.c | 2 +- 15 files changed, 114 insertions(+), 104 deletions(-) (limited to 'include/uapi/linux/time.h') diff --git a/Documentation/trace/ftrace.rst b/Documentation/trace/ftrace.rst index e45f0786f3f9..67d9c38e95eb 100644 --- a/Documentation/trace/ftrace.rst +++ b/Documentation/trace/ftrace.rst @@ -461,9 +461,17 @@ of ftrace. Here is a list of some of the key files: and ticks at the same rate as the hardware clocksource. boot: - Same as mono. Used to be a separate clock which accounted - for the time spent in suspend while CLOCK_MONOTONIC did - not. + This is the boot clock (CLOCK_BOOTTIME) and is based on the + fast monotonic clock, but also accounts for time spent in + suspend. Since the clock access is designed for use in + tracing in the suspend path, some side effects are possible + if clock is accessed after the suspend time is accounted before + the fast mono clock is updated. In this case, the clock update + appears to happen slightly sooner than it normally would have. + Also on 32-bit systems, it's possible that the 64-bit boot offset + sees a partial update. These effects are rare and post + processing should be able to handle them. See comments in the + ktime_get_boot_fast_ns() function for more information. To set a clock, simply echo the clock name into this file:: diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c index 46115a392098..c81c79d01d93 100644 --- a/drivers/input/evdev.c +++ b/drivers/input/evdev.c @@ -31,6 +31,7 @@ enum evdev_clock_type { EV_CLK_REAL = 0, EV_CLK_MONO, + EV_CLK_BOOT, EV_CLK_MAX }; @@ -197,10 +198,12 @@ static int evdev_set_clk_type(struct evdev_client *client, unsigned int clkid) case CLOCK_REALTIME: clk_type = EV_CLK_REAL; break; - case CLOCK_BOOTTIME: case CLOCK_MONOTONIC: clk_type = EV_CLK_MONO; break; + case CLOCK_BOOTTIME: + clk_type = EV_CLK_BOOT; + break; default: return -EINVAL; } @@ -311,6 +314,8 @@ static void evdev_events(struct input_handle *handle, ev_time[EV_CLK_MONO] = ktime_get(); ev_time[EV_CLK_REAL] = ktime_mono_to_real(ev_time[EV_CLK_MONO]); + ev_time[EV_CLK_BOOT] = ktime_mono_to_any(ev_time[EV_CLK_MONO], + TK_OFFS_BOOT); rcu_read_lock(); diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index a2656c3ebe81..3892e9c8b2de 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -161,9 +161,11 @@ struct hrtimer_clock_base { enum hrtimer_base_type { HRTIMER_BASE_MONOTONIC, HRTIMER_BASE_REALTIME, + HRTIMER_BASE_BOOTTIME, HRTIMER_BASE_TAI, HRTIMER_BASE_MONOTONIC_SOFT, HRTIMER_BASE_REALTIME_SOFT, + HRTIMER_BASE_BOOTTIME_SOFT, HRTIMER_BASE_TAI_SOFT, HRTIMER_MAX_CLOCK_BASES, }; diff --git a/include/linux/timekeeper_internal.h b/include/linux/timekeeper_internal.h index 4b3dca173e89..7acb953298a7 100644 --- a/include/linux/timekeeper_internal.h +++ b/include/linux/timekeeper_internal.h @@ -52,7 +52,6 @@ struct tk_read_base { * @offs_real: Offset clock monotonic -> clock realtime * @offs_boot: Offset clock monotonic -> clock boottime * @offs_tai: Offset clock monotonic -> clock tai - * @time_suspended: Accumulated suspend time * @tai_offset: The current UTC to TAI offset in seconds * @clock_was_set_seq: The sequence number of clock was set events * @cs_was_changed_seq: The sequence number of clocksource change events @@ -95,7 +94,6 @@ struct timekeeper { ktime_t offs_real; ktime_t offs_boot; ktime_t offs_tai; - ktime_t time_suspended; s32 tai_offset; unsigned int clock_was_set_seq; u8 cs_was_changed_seq; diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 9737fbec7019..588a0e4b1ab9 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -33,25 +33,20 @@ extern void ktime_get_ts64(struct timespec64 *ts); extern time64_t ktime_get_seconds(void); extern time64_t __ktime_get_real_seconds(void); extern time64_t ktime_get_real_seconds(void); -extern void ktime_get_active_ts64(struct timespec64 *ts); extern int __getnstimeofday64(struct timespec64 *tv); extern void getnstimeofday64(struct timespec64 *tv); extern void getboottime64(struct timespec64 *ts); -#define ktime_get_real_ts64(ts) getnstimeofday64(ts) - -/* Clock BOOTTIME compatibility wrappers */ -static inline void get_monotonic_boottime64(struct timespec64 *ts) -{ - ktime_get_ts64(ts); -} +#define ktime_get_real_ts64(ts) getnstimeofday64(ts) /* * ktime_t based interfaces */ + enum tk_offsets { TK_OFFS_REAL, + TK_OFFS_BOOT, TK_OFFS_TAI, TK_OFFS_MAX, }; @@ -62,10 +57,6 @@ extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs); extern ktime_t ktime_get_raw(void); extern u32 ktime_get_resolution_ns(void); -/* Clock BOOTTIME compatibility wrappers */ -static inline ktime_t ktime_get_boottime(void) { return ktime_get(); } -static inline u64 ktime_get_boot_ns(void) { return ktime_get(); } - /** * ktime_get_real - get the real (wall-) time in ktime_t format */ @@ -74,6 +65,17 @@ static inline ktime_t ktime_get_real(void) return ktime_get_with_offset(TK_OFFS_REAL); } +/** + * ktime_get_boottime - Returns monotonic time since boot in ktime_t format + * + * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the + * time spent in suspend. + */ +static inline ktime_t ktime_get_boottime(void) +{ + return ktime_get_with_offset(TK_OFFS_BOOT); +} + /** * ktime_get_clocktai - Returns the TAI time of day in ktime_t format */ @@ -100,6 +102,11 @@ static inline u64 ktime_get_real_ns(void) return ktime_to_ns(ktime_get_real()); } +static inline u64 ktime_get_boot_ns(void) +{ + return ktime_to_ns(ktime_get_boottime()); +} + static inline u64 ktime_get_tai_ns(void) { return ktime_to_ns(ktime_get_clocktai()); @@ -112,11 +119,17 @@ static inline u64 ktime_get_raw_ns(void) extern u64 ktime_get_mono_fast_ns(void); extern u64 ktime_get_raw_fast_ns(void); +extern u64 ktime_get_boot_fast_ns(void); extern u64 ktime_get_real_fast_ns(void); /* * timespec64 interfaces utilizing the ktime based ones */ +static inline void get_monotonic_boottime64(struct timespec64 *ts) +{ + *ts = ktime_to_timespec64(ktime_get_boottime()); +} + static inline void timekeeping_clocktai64(struct timespec64 *ts) { *ts = ktime_to_timespec64(ktime_get_clocktai()); diff --git a/include/uapi/linux/time.h b/include/uapi/linux/time.h index 16a296612ba4..4c0338ea308a 100644 --- a/include/uapi/linux/time.h +++ b/include/uapi/linux/time.h @@ -73,7 +73,6 @@ struct __kernel_old_timeval { */ #define CLOCK_SGI_CYCLE 10 #define CLOCK_TAI 11 -#define CLOCK_MONOTONIC_ACTIVE 12 #define MAX_CLOCKS 16 #define CLOCKS_MASK (CLOCK_REALTIME | CLOCK_MONOTONIC) diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index eda1210ce50f..14e858753d76 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -90,6 +90,11 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = .clockid = CLOCK_REALTIME, .get_time = &ktime_get_real, }, + { + .index = HRTIMER_BASE_BOOTTIME, + .clockid = CLOCK_BOOTTIME, + .get_time = &ktime_get_boottime, + }, { .index = HRTIMER_BASE_TAI, .clockid = CLOCK_TAI, @@ -105,6 +110,11 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) = .clockid = CLOCK_REALTIME, .get_time = &ktime_get_real, }, + { + .index = HRTIMER_BASE_BOOTTIME_SOFT, + .clockid = CLOCK_BOOTTIME, + .get_time = &ktime_get_boottime, + }, { .index = HRTIMER_BASE_TAI_SOFT, .clockid = CLOCK_TAI, @@ -119,7 +129,7 @@ static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = { [CLOCK_REALTIME] = HRTIMER_BASE_REALTIME, [CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC, - [CLOCK_BOOTTIME] = HRTIMER_BASE_MONOTONIC, + [CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME, [CLOCK_TAI] = HRTIMER_BASE_TAI, }; @@ -571,12 +581,14 @@ __hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base, unsigned int active_ static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base) { ktime_t *offs_real = &base->clock_base[HRTIMER_BASE_REALTIME].offset; + ktime_t *offs_boot = &base->clock_base[HRTIMER_BASE_BOOTTIME].offset; ktime_t *offs_tai = &base->clock_base[HRTIMER_BASE_TAI].offset; ktime_t now = ktime_get_update_offsets_now(&base->clock_was_set_seq, - offs_real, offs_tai); + offs_real, offs_boot, offs_tai); base->clock_base[HRTIMER_BASE_REALTIME_SOFT].offset = *offs_real; + base->clock_base[HRTIMER_BASE_BOOTTIME_SOFT].offset = *offs_boot; base->clock_base[HRTIMER_BASE_TAI_SOFT].offset = *offs_tai; return now; diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c index e0dbae98db9d..69a937c3cd81 100644 --- a/kernel/time/posix-stubs.c +++ b/kernel/time/posix-stubs.c @@ -83,8 +83,6 @@ int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp) case CLOCK_BOOTTIME: get_monotonic_boottime64(tp); break; - case CLOCK_MONOTONIC_ACTIVE: - ktime_get_active_ts64(tp); default: return -EINVAL; } diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index b6899b5060bd..10b7186d0638 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -252,16 +252,15 @@ static int posix_get_coarse_res(const clockid_t which_clock, struct timespec64 * return 0; } -static int posix_get_tai(clockid_t which_clock, struct timespec64 *tp) +static int posix_get_boottime(const clockid_t which_clock, struct timespec64 *tp) { - timekeeping_clocktai64(tp); + get_monotonic_boottime64(tp); return 0; } -static int posix_get_monotonic_active(clockid_t which_clock, - struct timespec64 *tp) +static int posix_get_tai(clockid_t which_clock, struct timespec64 *tp) { - ktime_get_active_ts64(tp); + timekeeping_clocktai64(tp); return 0; } @@ -1317,9 +1316,19 @@ static const struct k_clock clock_tai = { .timer_arm = common_hrtimer_arm, }; -static const struct k_clock clock_monotonic_active = { +static const struct k_clock clock_boottime = { .clock_getres = posix_get_hrtimer_res, - .clock_get = posix_get_monotonic_active, + .clock_get = posix_get_boottime, + .nsleep = common_nsleep, + .timer_create = common_timer_create, + .timer_set = common_timer_set, + .timer_get = common_timer_get, + .timer_del = common_timer_del, + .timer_rearm = common_hrtimer_rearm, + .timer_forward = common_hrtimer_forward, + .timer_remaining = common_hrtimer_remaining, + .timer_try_to_cancel = common_hrtimer_try_to_cancel, + .timer_arm = common_hrtimer_arm, }; static const struct k_clock * const posix_clocks[] = { @@ -1330,11 +1339,10 @@ static const struct k_clock * const posix_clocks[] = { [CLOCK_MONOTONIC_RAW] = &clock_monotonic_raw, [CLOCK_REALTIME_COARSE] = &clock_realtime_coarse, [CLOCK_MONOTONIC_COARSE] = &clock_monotonic_coarse, - [CLOCK_BOOTTIME] = &clock_monotonic, + [CLOCK_BOOTTIME] = &clock_boottime, [CLOCK_REALTIME_ALARM] = &alarm_clock, [CLOCK_BOOTTIME_ALARM] = &alarm_clock, [CLOCK_TAI] = &clock_tai, - [CLOCK_MONOTONIC_ACTIVE] = &clock_monotonic_active, }; static const struct k_clock *clockid_to_kclock(const clockid_t id) diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 099572ca4a8f..49edc1c4f3e6 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -419,19 +419,6 @@ void tick_suspend_local(void) clockevents_shutdown(td->evtdev); } -static void tick_forward_next_period(void) -{ - ktime_t delta, now = ktime_get(); - u64 n; - - delta = ktime_sub(now, tick_next_period); - n = ktime_divns(delta, tick_period); - tick_next_period += n * tick_period; - if (tick_next_period < now) - tick_next_period += tick_period; - tick_sched_forward_next_period(); -} - /** * tick_resume_local - Resume the local tick device * @@ -444,8 +431,6 @@ void tick_resume_local(void) struct tick_device *td = this_cpu_ptr(&tick_cpu_device); bool broadcast = tick_resume_check_broadcast(); - tick_forward_next_period(); - clockevents_tick_resume(td->evtdev); if (!broadcast) { if (td->mode == TICKDEV_MODE_PERIODIC) diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index 21efab7485ca..e277284c2831 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -141,12 +141,6 @@ static inline void tick_check_oneshot_broadcast_this_cpu(void) { } static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); } #endif /* !(BROADCAST && ONESHOT) */ -#if defined(CONFIG_NO_HZ_COMMON) || defined(CONFIG_HIGH_RES_TIMERS) -extern void tick_sched_forward_next_period(void); -#else -static inline void tick_sched_forward_next_period(void) { } -#endif - /* NO_HZ_FULL internal */ #ifdef CONFIG_NO_HZ_FULL extern void tick_nohz_init(void); diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index d31bec177fa5..da9455a6b42b 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -51,15 +51,6 @@ struct tick_sched *tick_get_tick_sched(int cpu) */ static ktime_t last_jiffies_update; -/* - * Called after resume. Make sure that jiffies are not fast forwarded due to - * clock monotonic being forwarded by the suspended time. - */ -void tick_sched_forward_next_period(void) -{ - last_jiffies_update = tick_next_period; -} - /* * Must be called with interrupts disabled ! */ diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index dcf7f20fcd12..49cbceef5deb 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -138,12 +138,7 @@ static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec64 wtm) static inline void tk_update_sleep_time(struct timekeeper *tk, ktime_t delta) { - /* Update both bases so mono and raw stay coupled. */ - tk->tkr_mono.base += delta; - tk->tkr_raw.base += delta; - - /* Accumulate time spent in suspend */ - tk->time_suspended += delta; + tk->offs_boot = ktime_add(tk->offs_boot, delta); } /* @@ -473,6 +468,36 @@ u64 ktime_get_raw_fast_ns(void) } EXPORT_SYMBOL_GPL(ktime_get_raw_fast_ns); +/** + * ktime_get_boot_fast_ns - NMI safe and fast access to boot clock. + * + * To keep it NMI safe since we're accessing from tracing, we're not using a + * separate timekeeper with updates to monotonic clock and boot offset + * protected with seqlocks. This has the following minor side effects: + * + * (1) Its possible that a timestamp be taken after the boot offset is updated + * but before the timekeeper is updated. If this happens, the new boot offset + * is added to the old timekeeping making the clock appear to update slightly + * earlier: + * CPU 0 CPU 1 + * timekeeping_inject_sleeptime64() + * __timekeeping_inject_sleeptime(tk, delta); + * timestamp(); + * timekeeping_update(tk, TK_CLEAR_NTP...); + * + * (2) On 32-bit systems, the 64-bit boot offset (tk->offs_boot) may be + * partially updated. Since the tk->offs_boot update is a rare event, this + * should be a rare occurrence which postprocessing should be able to handle. + */ +u64 notrace ktime_get_boot_fast_ns(void) +{ + struct timekeeper *tk = &tk_core.timekeeper; + + return (ktime_get_mono_fast_ns() + ktime_to_ns(tk->offs_boot)); +} +EXPORT_SYMBOL_GPL(ktime_get_boot_fast_ns); + + /* * See comment for __ktime_get_fast_ns() vs. timestamp ordering */ @@ -764,6 +789,7 @@ EXPORT_SYMBOL_GPL(ktime_get_resolution_ns); static ktime_t *offsets[TK_OFFS_MAX] = { [TK_OFFS_REAL] = &tk_core.timekeeper.offs_real, + [TK_OFFS_BOOT] = &tk_core.timekeeper.offs_boot, [TK_OFFS_TAI] = &tk_core.timekeeper.offs_tai, }; @@ -860,39 +886,6 @@ void ktime_get_ts64(struct timespec64 *ts) } EXPORT_SYMBOL_GPL(ktime_get_ts64); -/** - * ktime_get_active_ts64 - Get the active non-suspended monotonic clock - * @ts: pointer to timespec variable - * - * The function calculates the monotonic clock from the realtime clock and - * the wall_to_monotonic offset, subtracts the accumulated suspend time and - * stores the result in normalized timespec64 format in the variable - * pointed to by @ts. - */ -void ktime_get_active_ts64(struct timespec64 *ts) -{ - struct timekeeper *tk = &tk_core.timekeeper; - struct timespec64 tomono, tsusp; - u64 nsec, nssusp; - unsigned int seq; - - WARN_ON(timekeeping_suspended); - - do { - seq = read_seqcount_begin(&tk_core.seq); - ts->tv_sec = tk->xtime_sec; - nsec = timekeeping_get_ns(&tk->tkr_mono); - tomono = tk->wall_to_monotonic; - nssusp = tk->time_suspended; - } while (read_seqcount_retry(&tk_core.seq, seq)); - - ts->tv_sec += tomono.tv_sec; - ts->tv_nsec = 0; - timespec64_add_ns(ts, nsec + tomono.tv_nsec); - tsusp = ns_to_timespec64(nssusp); - *ts = timespec64_sub(*ts, tsusp); -} - /** * ktime_get_seconds - Get the seconds portion of CLOCK_MONOTONIC * @@ -1593,6 +1586,7 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk, return; } tk_xtime_add(tk, delta); + tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, *delta)); tk_update_sleep_time(tk, timespec64_to_ktime(*delta)); tk_debug_account_sleep_time(delta); } @@ -2125,7 +2119,7 @@ out: void getboottime64(struct timespec64 *ts) { struct timekeeper *tk = &tk_core.timekeeper; - ktime_t t = ktime_sub(tk->offs_real, tk->time_suspended); + ktime_t t = ktime_sub(tk->offs_real, tk->offs_boot); *ts = ktime_to_timespec64(t); } @@ -2188,6 +2182,7 @@ void do_timer(unsigned long ticks) * ktime_get_update_offsets_now - hrtimer helper * @cwsseq: pointer to check and store the clock was set sequence number * @offs_real: pointer to storage for monotonic -> realtime offset + * @offs_boot: pointer to storage for monotonic -> boottime offset * @offs_tai: pointer to storage for monotonic -> clock tai offset * * Returns current monotonic time and updates the offsets if the @@ -2197,7 +2192,7 @@ void do_timer(unsigned long ticks) * Called from hrtimer_interrupt() or retrigger_next_event() */ ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real, - ktime_t *offs_tai) + ktime_t *offs_boot, ktime_t *offs_tai) { struct timekeeper *tk = &tk_core.timekeeper; unsigned int seq; @@ -2214,6 +2209,7 @@ ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real, if (*cwsseq != tk->clock_was_set_seq) { *cwsseq = tk->clock_was_set_seq; *offs_real = tk->offs_real; + *offs_boot = tk->offs_boot; *offs_tai = tk->offs_tai; } diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h index 79b67f5e0343..7a9b4eb7a1d5 100644 --- a/kernel/time/timekeeping.h +++ b/kernel/time/timekeeping.h @@ -6,6 +6,7 @@ */ extern ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real, + ktime_t *offs_boot, ktime_t *offs_tai); extern int timekeeping_valid_for_hres(void); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index dfbcf9ee1447..414d7210b2ec 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1165,7 +1165,7 @@ static struct { { trace_clock, "perf", 1 }, { ktime_get_mono_fast_ns, "mono", 1 }, { ktime_get_raw_fast_ns, "mono_raw", 1 }, - { ktime_get_mono_fast_ns, "boot", 1 }, + { ktime_get_boot_fast_ns, "boot", 1 }, ARCH_TRACE_CLOCKS }; -- cgit v1.2.3