From f09cb9a1808e35ad7502ea39b6bfb443c7fa0f19 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 19 Mar 2015 09:39:08 +0100 Subject: time: Introduce tk_fast_raw Add the NMI safe CLOCK_MONOTONIC_RAW accessor.. Signed-off-by: Peter Zijlstra (Intel) Acked-by: John Stultz Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20150319093400.562746929@infradead.org Signed-off-by: Ingo Molnar --- include/linux/timekeeping.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/timekeeping.h') diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 3eaae4754275..f36b1edf3f73 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -220,6 +220,7 @@ static inline u64 ktime_get_raw_ns(void) } extern u64 ktime_get_mono_fast_ns(void); +extern u64 ktime_get_raw_fast_ns(void); /* * Timespec interfaces utilizing the ktime based ones -- cgit v1.3-14-g43fede From fe5fba05b46c791c95a9f34228ac495f81f72fc0 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 17 Mar 2015 12:39:10 +0100 Subject: time: Add ktime_get_tai_ns() Because it was the only clock for which we didn't have a _ns() accessor yet. Signed-off-by: Peter Zijlstra (Intel) Cc: John Stultz Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- include/linux/timekeeping.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/timekeeping.h') diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index f36b1edf3f73..5047b83483d6 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -214,6 +214,11 @@ 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()); +} + static inline u64 ktime_get_raw_ns(void) { return ktime_to_ns(ktime_get_raw()); -- cgit v1.3-14-g43fede From 9a806ddbb9a18c510e4acdcc828b9a87f5fd3aef Mon Sep 17 00:00:00 2001 From: Xunlei Pang Date: Wed, 1 Apr 2015 20:34:21 -0700 Subject: time: Add y2038 safe read_boot_clock64() As part of addressing in-kernel y2038 issues, this patch adds read_boot_clock64() and replaces all the call sites of read_boot_clock() with this function. This is a __weak implementation, which simply calls the existing y2038 unsafe read_boot_clock(). This allows architecture specific implementations to be converted independently, and eventually the y2038 unsafe read_boot_clock() can be removed after all its architecture specific implementations have been converted to read_boot_clock64(). Suggested-by: Arnd Bergmann Signed-off-by: Xunlei Pang Signed-off-by: John Stultz Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1427945681-29972-2-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar --- include/linux/timekeeping.h | 1 + kernel/time/timekeeping.c | 11 +++++++++-- 2 files changed, 10 insertions(+), 2 deletions(-) (limited to 'include/linux/timekeeping.h') diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 5047b83483d6..18d27a3f72ca 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -269,6 +269,7 @@ static inline bool has_persistent_clock(void) extern void read_persistent_clock(struct timespec *ts); extern void read_boot_clock(struct timespec *ts); +extern void read_boot_clock64(struct timespec64 *ts); extern int update_persistent_clock(struct timespec now); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 5b12292b343a..652e50a9c6ed 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1188,6 +1188,14 @@ void __weak read_boot_clock(struct timespec *ts) ts->tv_nsec = 0; } +void __weak read_boot_clock64(struct timespec64 *ts64) +{ + struct timespec ts; + + read_boot_clock(&ts); + *ts64 = timespec_to_timespec64(ts); +} + /* * timekeeping_init - Initializes the clocksource and common timekeeping values */ @@ -1209,8 +1217,7 @@ void __init timekeeping_init(void) } else if (now.tv_sec || now.tv_nsec) persistent_clock_exist = true; - read_boot_clock(&ts); - boot = timespec_to_timespec64(ts); + read_boot_clock64(&boot); if (!timespec64_valid_strict(&boot)) { pr_warn("WARNING: Boot clock returned invalid value!\n" " Check your CMOS/BIOS settings.\n"); -- cgit v1.3-14-g43fede From 2ee966320028ac846654eba5344540eeb4dc228d Mon Sep 17 00:00:00 2001 From: Xunlei Pang Date: Wed, 1 Apr 2015 20:34:22 -0700 Subject: time: Add y2038 safe read_persistent_clock64() As part of addressing in-kernel y2038 issues, this patch adds read_persistent_clock64() and replaces all the call sites of read_persistent_clock() with this function. This is a __weak implementation, which simply calls the existing y2038 unsafe read_persistent_clock(). This allows architecture specific implementations to be converted independently, and eventually the y2038 unsafe read_persistent_clock() can be removed after all its architecture specific implementations have been converted to read_persistent_clock64(). Suggested-by: Arnd Bergmann Signed-off-by: Xunlei Pang Signed-off-by: John Stultz Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1427945681-29972-3-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar --- arch/mips/lasat/sysctl.c | 4 ++-- include/linux/timekeeping.h | 1 + kernel/time/timekeeping.c | 22 ++++++++++++---------- 3 files changed, 15 insertions(+), 12 deletions(-) (limited to 'include/linux/timekeeping.h') diff --git a/arch/mips/lasat/sysctl.c b/arch/mips/lasat/sysctl.c index 3b7f65cc4218..cf9b4633257e 100644 --- a/arch/mips/lasat/sysctl.c +++ b/arch/mips/lasat/sysctl.c @@ -75,11 +75,11 @@ static int rtctmp; int proc_dolasatrtc(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { - struct timespec ts; + struct timespec64 ts; int r; if (!write) { - read_persistent_clock(&ts); + read_persistent_clock64(&ts); rtctmp = ts.tv_sec; /* check for time < 0 and set to 0 */ if (rtctmp < 0) diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 18d27a3f72ca..4c0f76f4616c 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -268,6 +268,7 @@ static inline bool has_persistent_clock(void) } extern void read_persistent_clock(struct timespec *ts); +extern void read_persistent_clock64(struct timespec64 *ts); extern void read_boot_clock(struct timespec *ts); extern void read_boot_clock64(struct timespec64 *ts); extern int update_persistent_clock(struct timespec now); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 652e50a9c6ed..b1dbfa573dce 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1173,6 +1173,14 @@ void __weak read_persistent_clock(struct timespec *ts) ts->tv_nsec = 0; } +void __weak read_persistent_clock64(struct timespec64 *ts64) +{ + struct timespec ts; + + read_persistent_clock(&ts); + *ts64 = timespec_to_timespec64(ts); +} + /** * read_boot_clock - Return time of the system start. * @@ -1205,10 +1213,8 @@ void __init timekeeping_init(void) struct clocksource *clock; unsigned long flags; struct timespec64 now, boot, tmp; - struct timespec ts; - read_persistent_clock(&ts); - now = timespec_to_timespec64(ts); + read_persistent_clock64(&now); if (!timespec64_valid_strict(&now)) { pr_warn("WARNING: Persistent clock returned invalid value!\n" " Check your CMOS/BIOS settings.\n"); @@ -1278,7 +1284,7 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk, * timekeeping_inject_sleeptime64 - Adds suspend interval to timeekeeping values * @delta: pointer to a timespec64 delta value * - * This hook is for architectures that cannot support read_persistent_clock + * This hook is for architectures that cannot support read_persistent_clock64 * because their RTC/persistent clock is only accessible when irqs are enabled. * * This function should only be called by rtc_resume(), and allows @@ -1325,12 +1331,10 @@ void timekeeping_resume(void) struct clocksource *clock = tk->tkr_mono.clock; unsigned long flags; struct timespec64 ts_new, ts_delta; - struct timespec tmp; cycle_t cycle_now, cycle_delta; bool suspendtime_found = false; - read_persistent_clock(&tmp); - ts_new = timespec_to_timespec64(tmp); + read_persistent_clock64(&ts_new); clockevents_resume(); clocksource_resume(); @@ -1406,10 +1410,8 @@ int timekeeping_suspend(void) unsigned long flags; struct timespec64 delta, delta_delta; static struct timespec64 old_delta; - struct timespec tmp; - read_persistent_clock(&tmp); - timekeeping_suspend_time = timespec_to_timespec64(tmp); + read_persistent_clock64(&timekeeping_suspend_time); /* * On some systems the persistent_clock can not be detected at -- cgit v1.3-14-g43fede From 3c00a1fe8496ff29ab62764bb3f4ce4b48089004 Mon Sep 17 00:00:00 2001 From: Xunlei Pang Date: Wed, 1 Apr 2015 20:34:23 -0700 Subject: time: Add y2038 safe update_persistent_clock64() As part of addressing in-kernel y2038 issues, this patch adds update_persistent_clock64() and replaces all the call sites of update_persistent_clock() with this function. This is a __weak implementation, which simply calls the existing y2038 unsafe update_persistent_clock(). This allows architecture specific implementations to be converted independently, and eventually y2038-unsafe update_persistent_clock() can be removed after all its architecture specific implementations have been converted to update_persistent_clock64(). Suggested-by: Arnd Bergmann Signed-off-by: Xunlei Pang Signed-off-by: John Stultz Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1427945681-29972-4-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar --- drivers/rtc/systohc.c | 2 +- include/linux/timekeeping.h | 1 + kernel/time/ntp.c | 13 ++++++++++++- 3 files changed, 14 insertions(+), 2 deletions(-) (limited to 'include/linux/timekeeping.h') diff --git a/drivers/rtc/systohc.c b/drivers/rtc/systohc.c index eb71872d0361..ef3c07a52c3a 100644 --- a/drivers/rtc/systohc.c +++ b/drivers/rtc/systohc.c @@ -11,7 +11,7 @@ * rtc_set_ntp_time - Save NTP synchronized time to the RTC * @now: Current time of day * - * Replacement for the NTP platform function update_persistent_clock + * Replacement for the NTP platform function update_persistent_clock64 * that stores time for later retrieval by rtc_hctosys. * * Returns 0 on successful RTC update, -ENODEV if a RTC update is not diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 4c0f76f4616c..7a2369d5b3f4 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -272,6 +272,7 @@ extern void read_persistent_clock64(struct timespec64 *ts); extern void read_boot_clock(struct timespec *ts); extern void read_boot_clock64(struct timespec64 *ts); extern int update_persistent_clock(struct timespec now); +extern int update_persistent_clock64(struct timespec64 now); #endif diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 9ad60d028508..7a681003001c 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -458,6 +458,16 @@ out: return leap; } +#ifdef CONFIG_GENERIC_CMOS_UPDATE +int __weak update_persistent_clock64(struct timespec64 now64) +{ + struct timespec now; + + now = timespec64_to_timespec(now64); + return update_persistent_clock(now); +} +#endif + #if defined(CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) static void sync_cmos_clock(struct work_struct *work); @@ -493,8 +503,9 @@ static void sync_cmos_clock(struct work_struct *work) if (persistent_clock_is_local) adjust.tv_sec -= (sys_tz.tz_minuteswest * 60); #ifdef CONFIG_GENERIC_CMOS_UPDATE - fail = update_persistent_clock(timespec64_to_timespec(adjust)); + fail = update_persistent_clock64(adjust); #endif + #ifdef CONFIG_RTC_SYSTOHC if (fail == -ENODEV) fail = rtc_set_ntp_time(adjust); -- cgit v1.3-14-g43fede From 0fa88cb4b82b5cf7429bc1cef9db006ca035754e Mon Sep 17 00:00:00 2001 From: Xunlei Pang Date: Wed, 1 Apr 2015 20:34:38 -0700 Subject: time, drivers/rtc: Don't bother with rtc_resume() for the nonstop clocksource If a system does not provide a persistent_clock(), the time will be updated on resume by rtc_resume(). With the addition of the non-stop clocksources for suspend timing, those systems set the time on resume in timekeeping_resume(), but may not provide a valid persistent_clock(). This results in the rtc_resume() logic thinking no one has set the time and it then will over-write the suspend time again, which is not necessary and only increases clock error. So, fix this for rtc_resume(). This patch also improves the name of persistent_clock_exist to make it more grammatical. Signed-off-by: Xunlei Pang Signed-off-by: John Stultz Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1427945681-29972-19-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar --- drivers/rtc/class.c | 4 +-- include/linux/timekeeping.h | 9 +++---- kernel/time/timekeeping.c | 66 +++++++++++++++++++++++++++++++++------------ 3 files changed, 54 insertions(+), 25 deletions(-) (limited to 'include/linux/timekeeping.h') diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c index d40760aa4553..c29ba7e14304 100644 --- a/drivers/rtc/class.c +++ b/drivers/rtc/class.c @@ -55,7 +55,7 @@ static int rtc_suspend(struct device *dev) struct timespec64 delta, delta_delta; int err; - if (has_persistent_clock()) + if (timekeeping_rtc_skipsuspend()) return 0; if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0) @@ -102,7 +102,7 @@ static int rtc_resume(struct device *dev) struct timespec64 sleep_time; int err; - if (has_persistent_clock()) + if (timekeeping_rtc_skipresume()) return 0; rtc_hctosys_ret = -ENODEV; diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 7a2369d5b3f4..99176af216af 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -248,6 +248,9 @@ static inline void timekeeping_clocktai(struct timespec *ts) /* * RTC specific */ +extern bool timekeeping_rtc_skipsuspend(void); +extern bool timekeeping_rtc_skipresume(void); + extern void timekeeping_inject_sleeptime64(struct timespec64 *delta); /* @@ -259,14 +262,8 @@ extern void getnstime_raw_and_real(struct timespec *ts_raw, /* * Persistent clock related interfaces */ -extern bool persistent_clock_exist; extern int persistent_clock_is_local; -static inline bool has_persistent_clock(void) -{ - return persistent_clock_exist; -} - extern void read_persistent_clock(struct timespec *ts); extern void read_persistent_clock64(struct timespec64 *ts); extern void read_boot_clock(struct timespec *ts); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index b7db4916415b..79b9bc6e7876 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -64,9 +64,6 @@ static struct tk_fast tk_fast_raw ____cacheline_aligned; /* flag for if timekeeping is suspended */ int __read_mostly timekeeping_suspended; -/* Flag for if there is a persistent clock on this platform */ -bool __read_mostly persistent_clock_exist = false; - static inline void tk_normalize_xtime(struct timekeeper *tk) { while (tk->tkr_mono.xtime_nsec >= ((u64)NSEC_PER_SEC << tk->tkr_mono.shift)) { @@ -1204,6 +1201,12 @@ void __weak read_boot_clock64(struct timespec64 *ts64) *ts64 = timespec_to_timespec64(ts); } +/* Flag for if timekeeping_resume() has injected sleeptime */ +static bool sleeptime_injected; + +/* Flag for if there is a persistent clock on this platform */ +static bool persistent_clock_exists; + /* * timekeeping_init - Initializes the clocksource and common timekeeping values */ @@ -1221,7 +1224,7 @@ void __init timekeeping_init(void) now.tv_sec = 0; now.tv_nsec = 0; } else if (now.tv_sec || now.tv_nsec) - persistent_clock_exist = true; + persistent_clock_exists = true; read_boot_clock64(&boot); if (!timespec64_valid_strict(&boot)) { @@ -1281,12 +1284,48 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk, } #if defined(CONFIG_PM_SLEEP) && defined(CONFIG_RTC_HCTOSYS_DEVICE) +/** + * We have three kinds of time sources to use for sleep time + * injection, the preference order is: + * 1) non-stop clocksource + * 2) persistent clock (ie: RTC accessible when irqs are off) + * 3) RTC + * + * 1) and 2) are used by timekeeping, 3) by RTC subsystem. + * If system has neither 1) nor 2), 3) will be used finally. + * + * + * If timekeeping has injected sleeptime via either 1) or 2), + * 3) becomes needless, so in this case we don't need to call + * rtc_resume(), and this is what timekeeping_rtc_skipresume() + * means. + */ +bool timekeeping_rtc_skipresume(void) +{ + return sleeptime_injected; +} + +/** + * 1) can be determined whether to use or not only when doing + * timekeeping_resume() which is invoked after rtc_suspend(), + * so we can't skip rtc_suspend() surely if system has 1). + * + * But if system has 2), 2) will definitely be used, so in this + * case we don't need to call rtc_suspend(), and this is what + * timekeeping_rtc_skipsuspend() means. + */ +bool timekeeping_rtc_skipsuspend(void) +{ + return persistent_clock_exists; +} + /** * timekeeping_inject_sleeptime64 - Adds suspend interval to timeekeeping values * @delta: pointer to a timespec64 delta value * * This hook is for architectures that cannot support read_persistent_clock64 * because their RTC/persistent clock is only accessible when irqs are enabled. + * and also don't have an effective nonstop clocksource. * * This function should only be called by rtc_resume(), and allows * a suspend offset to be injected into the timekeeping values. @@ -1296,13 +1335,6 @@ void timekeeping_inject_sleeptime64(struct timespec64 *delta) struct timekeeper *tk = &tk_core.timekeeper; unsigned long flags; - /* - * Make sure we don't set the clock twice, as timekeeping_resume() - * already did it - */ - if (has_persistent_clock()) - return; - raw_spin_lock_irqsave(&timekeeper_lock, flags); write_seqcount_begin(&tk_core.seq); @@ -1334,8 +1366,8 @@ void timekeeping_resume(void) unsigned long flags; struct timespec64 ts_new, ts_delta; cycle_t cycle_now, cycle_delta; - bool suspendtime_found = false; + sleeptime_injected = false; read_persistent_clock64(&ts_new); clockevents_resume(); @@ -1381,13 +1413,13 @@ void timekeeping_resume(void) nsec += ((u64) cycle_delta * mult) >> shift; ts_delta = ns_to_timespec64(nsec); - suspendtime_found = true; + sleeptime_injected = true; } else if (timespec64_compare(&ts_new, &timekeeping_suspend_time) > 0) { ts_delta = timespec64_sub(ts_new, timekeeping_suspend_time); - suspendtime_found = true; + sleeptime_injected = true; } - if (suspendtime_found) + if (sleeptime_injected) __timekeeping_inject_sleeptime(tk, &ts_delta); /* Re-base the last cycle value */ @@ -1421,14 +1453,14 @@ int timekeeping_suspend(void) * value returned, update the persistent_clock_exists flag. */ if (timekeeping_suspend_time.tv_sec || timekeeping_suspend_time.tv_nsec) - persistent_clock_exist = true; + persistent_clock_exists = true; raw_spin_lock_irqsave(&timekeeper_lock, flags); write_seqcount_begin(&tk_core.seq); timekeeping_forward_now(tk); timekeeping_suspended = 1; - if (has_persistent_clock()) { + if (persistent_clock_exists) { /* * To avoid drift caused by repeated suspend/resumes, * which each can add ~1 second drift error, -- cgit v1.3-14-g43fede