Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
authorLinus Torvalds <torvalds@linux-foundation.org>
Sun, 31 Jan 2016 23:49:06 +0000 (15:49 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sun, 31 Jan 2016 23:49:06 +0000 (15:49 -0800)
Pull timer fixes from Thomas Gleixner:
 "The timer departement delivers:

   - a regression fix for the NTP code along with a proper selftest
   - prevent a spurious timer interrupt in the NOHZ lowres code
   - a fix for user space interfaces returning the remaining time on
     architectures with CONFIG_TIME_LOW_RES=y
   - a few patches to fix COMPILE_TEST fallout"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick/nohz: Set the correct expiry when switching to nohz/lowres mode
  clocksource: Fix dependencies for archs w/o HAS_IOMEM
  clocksource: Select CLKSRC_MMIO where needed
  tick/sched: Hide unused oneshot timer code
  kselftests: timers: Add adjtimex SETOFFSET validity tests
  ntp: Fix ADJ_SETOFFSET being used w/ ADJ_NANO
  itimers: Handle relative timers with CONFIG_TIME_LOW_RES proper
  posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper
  timerfd: Handle relative timers with CONFIG_TIME_LOW_RES proper
  hrtimer: Handle remaining time proper for TIME_LOW_RES
  clockevents/tcb_clksrc: Prevent disabling an already disabled clock

drivers/clocksource/Kconfig
drivers/clocksource/tcb_clksrc.c
fs/timerfd.c
include/linux/hrtimer.h
kernel/time/hrtimer.c
kernel/time/itimer.c
kernel/time/ntp.c
kernel/time/posix-timers.c
kernel/time/tick-sched.c
kernel/time/timer_list.c
tools/testing/selftests/timers/valid-adjtimex.c

index 56777f0..33db740 100644 (file)
@@ -30,6 +30,8 @@ config CLKSRC_MMIO
 config DIGICOLOR_TIMER
        bool "Digicolor timer driver" if COMPILE_TEST
        depends on GENERIC_CLOCKEVENTS
+       select CLKSRC_MMIO
+       depends on HAS_IOMEM
        help
          Enables the support for the digicolor timer driver.
 
@@ -55,6 +57,7 @@ config ARMADA_370_XP_TIMER
        bool "Armada 370 and XP timer driver" if COMPILE_TEST
        depends on ARM
        select CLKSRC_OF
+       select CLKSRC_MMIO
        help
          Enables the support for the Armada 370 and XP timer driver.
 
@@ -76,6 +79,7 @@ config ORION_TIMER
 config SUN4I_TIMER
        bool "Sun4i timer driver" if COMPILE_TEST
        depends on GENERIC_CLOCKEVENTS
+       depends on HAS_IOMEM
        select CLKSRC_MMIO
        help
          Enables support for the Sun4i timer.
@@ -89,6 +93,7 @@ config SUN5I_HSTIMER
 
 config TEGRA_TIMER
        bool "Tegra timer driver" if COMPILE_TEST
+       select CLKSRC_MMIO
        depends on ARM
        help
          Enables support for the Tegra driver.
@@ -96,6 +101,7 @@ config TEGRA_TIMER
 config VT8500_TIMER
        bool "VT8500 timer driver" if COMPILE_TEST
        depends on GENERIC_CLOCKEVENTS
+       depends on HAS_IOMEM
        help
          Enables support for the VT8500 driver.
 
@@ -131,6 +137,7 @@ config CLKSRC_NOMADIK_MTU_SCHED_CLOCK
 config CLKSRC_DBX500_PRCMU
        bool "Clocksource PRCMU Timer" if COMPILE_TEST
        depends on GENERIC_CLOCKEVENTS
+       depends on HAS_IOMEM
        help
          Use the always on PRCMU Timer as clocksource
 
@@ -248,6 +255,7 @@ config CLKSRC_EXYNOS_MCT
 config CLKSRC_SAMSUNG_PWM
        bool "PWM timer drvier for Samsung S3C, S5P" if COMPILE_TEST
        depends on GENERIC_CLOCKEVENTS
+       depends on HAS_IOMEM
        help
          This is a new clocksource driver for the PWM timer found in
          Samsung S3C, S5P and Exynos SoCs, replacing an earlier driver
@@ -257,12 +265,14 @@ config CLKSRC_SAMSUNG_PWM
 config FSL_FTM_TIMER
        bool "Freescale FlexTimer Module driver" if COMPILE_TEST
        depends on GENERIC_CLOCKEVENTS
+       depends on HAS_IOMEM
        select CLKSRC_MMIO
        help
          Support for Freescale FlexTimer Module (FTM) timer.
 
 config VF_PIT_TIMER
        bool
+       select CLKSRC_MMIO
        help
          Support for Period Interrupt Timer on Freescale Vybrid Family SoCs.
 
@@ -360,6 +370,7 @@ config CLKSRC_TANGO_XTAL
 config CLKSRC_PXA
        bool "Clocksource for PXA or SA-11x0 platform" if COMPILE_TEST
        depends on GENERIC_CLOCKEVENTS
+       depends on HAS_IOMEM
        select CLKSRC_MMIO
        help
          This enables OST0 support available on PXA and SA-11x0
@@ -394,6 +405,7 @@ config CLKSRC_ST_LPC
        bool "Low power clocksource found in the LPC" if COMPILE_TEST
        select CLKSRC_OF if OF
        depends on HAS_IOMEM
+       select CLKSRC_MMIO
        help
          Enable this option to use the Low Power controller timer
          as clocksource.
index 6ee9140..4da2af9 100644 (file)
@@ -98,7 +98,8 @@ static int tc_shutdown(struct clock_event_device *d)
 
        __raw_writel(0xff, regs + ATMEL_TC_REG(2, IDR));
        __raw_writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
-       clk_disable(tcd->clk);
+       if (!clockevent_state_detached(d))
+               clk_disable(tcd->clk);
 
        return 0;
 }
index b94fa6c..053818d 100644 (file)
@@ -153,7 +153,7 @@ static ktime_t timerfd_get_remaining(struct timerfd_ctx *ctx)
        if (isalarm(ctx))
                remaining = alarm_expires_remaining(&ctx->t.alarm);
        else
-               remaining = hrtimer_expires_remaining(&ctx->t.tmr);
+               remaining = hrtimer_expires_remaining_adjusted(&ctx->t.tmr);
 
        return remaining.tv64 < 0 ? ktime_set(0, 0): remaining;
 }
index 76dd4f0..2ead22d 100644 (file)
@@ -87,7 +87,8 @@ enum hrtimer_restart {
  * @function:  timer expiry callback function
  * @base:      pointer to the timer base (per cpu and per clock)
  * @state:     state information (See bit values above)
- * @start_pid: timer statistics field to store the pid of the task which
+ * @is_rel:    Set if the timer was armed relative
+ * @start_pid:  timer statistics field to store the pid of the task which
  *             started the timer
  * @start_site:        timer statistics field to store the site where the timer
  *             was started
@@ -101,7 +102,8 @@ struct hrtimer {
        ktime_t                         _softexpires;
        enum hrtimer_restart            (*function)(struct hrtimer *);
        struct hrtimer_clock_base       *base;
-       unsigned long                   state;
+       u8                              state;
+       u8                              is_rel;
 #ifdef CONFIG_TIMER_STATS
        int                             start_pid;
        void                            *start_site;
@@ -321,6 +323,27 @@ static inline void clock_was_set_delayed(void) { }
 
 #endif
 
+static inline ktime_t
+__hrtimer_expires_remaining_adjusted(const struct hrtimer *timer, ktime_t now)
+{
+       ktime_t rem = ktime_sub(timer->node.expires, now);
+
+       /*
+        * Adjust relative timers for the extra we added in
+        * hrtimer_start_range_ns() to prevent short timeouts.
+        */
+       if (IS_ENABLED(CONFIG_TIME_LOW_RES) && timer->is_rel)
+               rem.tv64 -= hrtimer_resolution;
+       return rem;
+}
+
+static inline ktime_t
+hrtimer_expires_remaining_adjusted(const struct hrtimer *timer)
+{
+       return __hrtimer_expires_remaining_adjusted(timer,
+                                                   timer->base->get_time());
+}
+
 extern void clock_was_set(void);
 #ifdef CONFIG_TIMERFD
 extern void timerfd_clock_was_set(void);
@@ -390,7 +413,12 @@ static inline void hrtimer_restart(struct hrtimer *timer)
 }
 
 /* Query timers: */
-extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer);
+extern ktime_t __hrtimer_get_remaining(const struct hrtimer *timer, bool adjust);
+
+static inline ktime_t hrtimer_get_remaining(const struct hrtimer *timer)
+{
+       return __hrtimer_get_remaining(timer, false);
+}
 
 extern u64 hrtimer_get_next_event(void);
 
index 435b885..fa909f9 100644 (file)
@@ -897,10 +897,10 @@ static int enqueue_hrtimer(struct hrtimer *timer,
  */
 static void __remove_hrtimer(struct hrtimer *timer,
                             struct hrtimer_clock_base *base,
-                            unsigned long newstate, int reprogram)
+                            u8 newstate, int reprogram)
 {
        struct hrtimer_cpu_base *cpu_base = base->cpu_base;
-       unsigned int state = timer->state;
+       u8 state = timer->state;
 
        timer->state = newstate;
        if (!(state & HRTIMER_STATE_ENQUEUED))
@@ -930,7 +930,7 @@ static inline int
 remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base, bool restart)
 {
        if (hrtimer_is_queued(timer)) {
-               unsigned long state = timer->state;
+               u8 state = timer->state;
                int reprogram;
 
                /*
@@ -954,6 +954,22 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base, bool rest
        return 0;
 }
 
+static inline ktime_t hrtimer_update_lowres(struct hrtimer *timer, ktime_t tim,
+                                           const enum hrtimer_mode mode)
+{
+#ifdef CONFIG_TIME_LOW_RES
+       /*
+        * CONFIG_TIME_LOW_RES indicates that the system has no way to return
+        * granular time values. For relative timers we add hrtimer_resolution
+        * (i.e. one jiffie) to prevent short timeouts.
+        */
+       timer->is_rel = mode & HRTIMER_MODE_REL;
+       if (timer->is_rel)
+               tim = ktime_add_safe(tim, ktime_set(0, hrtimer_resolution));
+#endif
+       return tim;
+}
+
 /**
  * hrtimer_start_range_ns - (re)start an hrtimer on the current CPU
  * @timer:     the timer to be added
@@ -974,19 +990,10 @@ void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
        /* Remove an active timer from the queue: */
        remove_hrtimer(timer, base, true);
 
-       if (mode & HRTIMER_MODE_REL) {
+       if (mode & HRTIMER_MODE_REL)
                tim = ktime_add_safe(tim, base->get_time());
-               /*
-                * CONFIG_TIME_LOW_RES is a temporary way for architectures
-                * to signal that they simply return xtime in
-                * do_gettimeoffset(). In this case we want to round up by
-                * resolution when starting a relative timer, to avoid short
-                * timeouts. This will go away with the GTOD framework.
-                */
-#ifdef CONFIG_TIME_LOW_RES
-               tim = ktime_add_safe(tim, ktime_set(0, hrtimer_resolution));
-#endif
-       }
+
+       tim = hrtimer_update_lowres(timer, tim, mode);
 
        hrtimer_set_expires_range_ns(timer, tim, delta_ns);
 
@@ -1074,19 +1081,23 @@ EXPORT_SYMBOL_GPL(hrtimer_cancel);
 /**
  * hrtimer_get_remaining - get remaining time for the timer
  * @timer:     the timer to read
+ * @adjust:    adjust relative timers when CONFIG_TIME_LOW_RES=y
  */
-ktime_t hrtimer_get_remaining(const struct hrtimer *timer)
+ktime_t __hrtimer_get_remaining(const struct hrtimer *timer, bool adjust)
 {
        unsigned long flags;
        ktime_t rem;
 
        lock_hrtimer_base(timer, &flags);
-       rem = hrtimer_expires_remaining(timer);
+       if (IS_ENABLED(CONFIG_TIME_LOW_RES) && adjust)
+               rem = hrtimer_expires_remaining_adjusted(timer);
+       else
+               rem = hrtimer_expires_remaining(timer);
        unlock_hrtimer_base(timer, &flags);
 
        return rem;
 }
-EXPORT_SYMBOL_GPL(hrtimer_get_remaining);
+EXPORT_SYMBOL_GPL(__hrtimer_get_remaining);
 
 #ifdef CONFIG_NO_HZ_COMMON
 /**
@@ -1219,6 +1230,14 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base,
        timer_stats_account_hrtimer(timer);
        fn = timer->function;
 
+       /*
+        * Clear the 'is relative' flag for the TIME_LOW_RES case. If the
+        * timer is restarted with a period then it becomes an absolute
+        * timer. If its not restarted it does not matter.
+        */
+       if (IS_ENABLED(CONFIG_TIME_LOW_RES))
+               timer->is_rel = false;
+
        /*
         * Because we run timers from hardirq context, there is no chance
         * they get migrated to another cpu, therefore its safe to unlock
index 8d262b4..1d5c720 100644 (file)
@@ -26,7 +26,7 @@
  */
 static struct timeval itimer_get_remtime(struct hrtimer *timer)
 {
-       ktime_t rem = hrtimer_get_remaining(timer);
+       ktime_t rem = __hrtimer_get_remaining(timer, true);
 
        /*
         * Racy but safe: if the itimer expires after the above
index 36f2ca0..6df8927 100644 (file)
@@ -685,8 +685,18 @@ int ntp_validate_timex(struct timex *txc)
                if (!capable(CAP_SYS_TIME))
                        return -EPERM;
 
-               if (!timeval_inject_offset_valid(&txc->time))
-                       return -EINVAL;
+               if (txc->modes & ADJ_NANO) {
+                       struct timespec ts;
+
+                       ts.tv_sec = txc->time.tv_sec;
+                       ts.tv_nsec = txc->time.tv_usec;
+                       if (!timespec_inject_offset_valid(&ts))
+                               return -EINVAL;
+
+               } else {
+                       if (!timeval_inject_offset_valid(&txc->time))
+                               return -EINVAL;
+               }
        }
 
        /*
index 31d11ac..f2826c3 100644 (file)
@@ -760,7 +760,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
            (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
                timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
 
-       remaining = ktime_sub(hrtimer_get_expires(timer), now);
+       remaining = __hrtimer_expires_remaining_adjusted(timer, now);
        /* Return 0 only, when the timer is expired and not pending */
        if (remaining.tv64 <= 0) {
                /*
index 9d7a053..0b17424 100644 (file)
  */
 static DEFINE_PER_CPU(struct tick_sched, tick_cpu_sched);
 
-/*
- * The time, when the last jiffy update happened. Protected by jiffies_lock.
- */
-static ktime_t last_jiffies_update;
-
 struct tick_sched *tick_get_tick_sched(int cpu)
 {
        return &per_cpu(tick_cpu_sched, cpu);
 }
 
+#if defined(CONFIG_NO_HZ_COMMON) || defined(CONFIG_HIGH_RES_TIMERS)
+/*
+ * The time, when the last jiffy update happened. Protected by jiffies_lock.
+ */
+static ktime_t last_jiffies_update;
+
 /*
  * Must be called with interrupts disabled !
  */
@@ -151,6 +152,7 @@ static void tick_sched_handle(struct tick_sched *ts, struct pt_regs *regs)
        update_process_times(user_mode(regs));
        profile_tick(CPU_PROFILING);
 }
+#endif
 
 #ifdef CONFIG_NO_HZ_FULL
 cpumask_var_t tick_nohz_full_mask;
@@ -993,9 +995,9 @@ static void tick_nohz_switch_to_nohz(void)
        /* Get the next period */
        next = tick_init_jiffy_update();
 
-       hrtimer_forward_now(&ts->sched_timer, tick_period);
        hrtimer_set_expires(&ts->sched_timer, next);
-       tick_program_event(next, 1);
+       hrtimer_forward_now(&ts->sched_timer, tick_period);
+       tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1);
        tick_nohz_activate(ts, NOHZ_MODE_LOWRES);
 }
 
index f75e35b..ba7d8b2 100644 (file)
@@ -69,7 +69,7 @@ print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer,
        print_name_offset(m, taddr);
        SEQ_printf(m, ", ");
        print_name_offset(m, timer->function);
-       SEQ_printf(m, ", S:%02lx", timer->state);
+       SEQ_printf(m, ", S:%02x", timer->state);
 #ifdef CONFIG_TIMER_STATS
        SEQ_printf(m, ", ");
        print_name_offset(m, timer->start_site);
index e86d937..60fe3c5 100644 (file)
@@ -45,7 +45,17 @@ static inline int ksft_exit_fail(void)
 }
 #endif
 
-#define NSEC_PER_SEC 1000000000L
+#define NSEC_PER_SEC 1000000000LL
+#define USEC_PER_SEC 1000000LL
+
+#define ADJ_SETOFFSET 0x0100
+
+#include <sys/syscall.h>
+static int clock_adjtime(clockid_t id, struct timex *tx)
+{
+       return syscall(__NR_clock_adjtime, id, tx);
+}
+
 
 /* clear NTP time_status & time_state */
 int clear_time_state(void)
@@ -193,10 +203,137 @@ out:
 }
 
 
+int set_offset(long long offset, int use_nano)
+{
+       struct timex tmx = {};
+       int ret;
+
+       tmx.modes = ADJ_SETOFFSET;
+       if (use_nano) {
+               tmx.modes |= ADJ_NANO;
+
+               tmx.time.tv_sec = offset / NSEC_PER_SEC;
+               tmx.time.tv_usec = offset % NSEC_PER_SEC;
+
+               if (offset < 0 && tmx.time.tv_usec) {
+                       tmx.time.tv_sec -= 1;
+                       tmx.time.tv_usec += NSEC_PER_SEC;
+               }
+       } else {
+               tmx.time.tv_sec = offset / USEC_PER_SEC;
+               tmx.time.tv_usec = offset % USEC_PER_SEC;
+
+               if (offset < 0 && tmx.time.tv_usec) {
+                       tmx.time.tv_sec -= 1;
+                       tmx.time.tv_usec += USEC_PER_SEC;
+               }
+       }
+
+       ret = clock_adjtime(CLOCK_REALTIME, &tmx);
+       if (ret < 0) {
+               printf("(sec: %ld  usec: %ld) ", tmx.time.tv_sec, tmx.time.tv_usec);
+               printf("[FAIL]\n");
+               return -1;
+       }
+       return 0;
+}
+
+int set_bad_offset(long sec, long usec, int use_nano)
+{
+       struct timex tmx = {};
+       int ret;
+
+       tmx.modes = ADJ_SETOFFSET;
+       if (use_nano)
+               tmx.modes |= ADJ_NANO;
+
+       tmx.time.tv_sec = sec;
+       tmx.time.tv_usec = usec;
+       ret = clock_adjtime(CLOCK_REALTIME, &tmx);
+       if (ret >= 0) {
+               printf("Invalid (sec: %ld  usec: %ld) did not fail! ", tmx.time.tv_sec, tmx.time.tv_usec);
+               printf("[FAIL]\n");
+               return -1;
+       }
+       return 0;
+}
+
+int validate_set_offset(void)
+{
+       printf("Testing ADJ_SETOFFSET... ");
+
+       /* Test valid values */
+       if (set_offset(NSEC_PER_SEC - 1, 1))
+               return -1;
+
+       if (set_offset(-NSEC_PER_SEC + 1, 1))
+               return -1;
+
+       if (set_offset(-NSEC_PER_SEC - 1, 1))
+               return -1;
+
+       if (set_offset(5 * NSEC_PER_SEC, 1))
+               return -1;
+
+       if (set_offset(-5 * NSEC_PER_SEC, 1))
+               return -1;
+
+       if (set_offset(5 * NSEC_PER_SEC + NSEC_PER_SEC / 2, 1))
+               return -1;
+
+       if (set_offset(-5 * NSEC_PER_SEC - NSEC_PER_SEC / 2, 1))
+               return -1;
+
+       if (set_offset(USEC_PER_SEC - 1, 0))
+               return -1;
+
+       if (set_offset(-USEC_PER_SEC + 1, 0))
+               return -1;
+
+       if (set_offset(-USEC_PER_SEC - 1, 0))
+               return -1;
+
+       if (set_offset(5 * USEC_PER_SEC, 0))
+               return -1;
+
+       if (set_offset(-5 * USEC_PER_SEC, 0))
+               return -1;
+
+       if (set_offset(5 * USEC_PER_SEC + USEC_PER_SEC / 2, 0))
+               return -1;
+
+       if (set_offset(-5 * USEC_PER_SEC - USEC_PER_SEC / 2, 0))
+               return -1;
+
+       /* Test invalid values */
+       if (set_bad_offset(0, -1, 1))
+               return -1;
+       if (set_bad_offset(0, -1, 0))
+               return -1;
+       if (set_bad_offset(0, 2 * NSEC_PER_SEC, 1))
+               return -1;
+       if (set_bad_offset(0, 2 * USEC_PER_SEC, 0))
+               return -1;
+       if (set_bad_offset(0, NSEC_PER_SEC, 1))
+               return -1;
+       if (set_bad_offset(0, USEC_PER_SEC, 0))
+               return -1;
+       if (set_bad_offset(0, -NSEC_PER_SEC, 1))
+               return -1;
+       if (set_bad_offset(0, -USEC_PER_SEC, 0))
+               return -1;
+
+       printf("[OK]\n");
+       return 0;
+}
+
 int main(int argc, char **argv)
 {
        if (validate_freq())
                return ksft_exit_fail();
 
+       if (validate_set_offset())
+               return ksft_exit_fail();
+
        return ksft_exit_pass();
 }