Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull core timer updates from Thomas Gleixner:
 "Timers and timekeeping updates:

   - A large overhaul of the posix CPU timer code which is a preparation
     for moving the CPU timer expiry out into task work so it can be
     properly accounted on the task/process.

     An update to the bogus permission checks will come later during the
     merge window as feedback was not complete before heading of for
     travel.

   - Switch the timerqueue code to use cached rbtrees and get rid of the
     homebrewn caching of the leftmost node.

   - Consolidate hrtimer_init() + hrtimer_init_sleeper() calls into a
     single function

   - Implement the separation of hrtimers to be forced to expire in hard
     interrupt context even when PREEMPT_RT is enabled and mark the
     affected timers accordingly.

   - Implement a mechanism for hrtimers and the timer wheel to protect
     RT against priority inversion and live lock issues when a (hr)timer
     which should be canceled is currently executing the callback.
     Instead of infinitely spinning, the task which tries to cancel the
     timer blocks on a per cpu base expiry lock which is held and
     released by the (hr)timer expiry code.

   - Enable the Hyper-V TSC page based sched_clock for Hyper-V guests
     resulting in faster access to timekeeping functions.

   - Updates to various clocksource/clockevent drivers and their device
     tree bindings.

   - The usual small improvements all over the place"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
  posix-cpu-timers: Fix permission check regression
  posix-cpu-timers: Always clear head pointer on dequeue
  hrtimer: Add a missing bracket and hide `migration_base' on !SMP
  posix-cpu-timers: Make expiry_active check actually work correctly
  posix-timers: Unbreak CONFIG_POSIX_TIMERS=n build
  tick: Mark sched_timer to expire in hard interrupt context
  hrtimer: Add kernel doc annotation for HRTIMER_MODE_HARD
  x86/hyperv: Hide pv_ops access for CONFIG_PARAVIRT=n
  posix-cpu-timers: Utilize timerqueue for storage
  posix-cpu-timers: Move state tracking to struct posix_cputimers
  posix-cpu-timers: Deduplicate rlimit handling
  posix-cpu-timers: Remove pointless comparisons
  posix-cpu-timers: Get rid of 64bit divisions
  posix-cpu-timers: Consolidate timer expiry further
  posix-cpu-timers: Get rid of zero checks
  rlimit: Rewrite non-sensical RLIMIT_CPU comment
  posix-cpu-timers: Respect INFINITY for hard RTTIME limit
  posix-cpu-timers: Switch thread group sampling to array
  posix-cpu-timers: Restructure expiry array
  posix-cpu-timers: Remove cputime_expires
  ...

1 files changed, 10 insertions, 7 deletions

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index be9707f68024..955851748dc3 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -634,10 +634,12 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
         /* Forward the time to expire in the future */
         hrtimer_forward(&ts->sched_timer, now, tick_period);
 
-        if (ts->nohz_mode == NOHZ_MODE_HIGHRES)
-                hrtimer_start_expires(&ts->sched_timer, HRTIMER_MODE_ABS_PINNED);
-        else
+        if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
+                hrtimer_start_expires(&ts->sched_timer,
+                                      HRTIMER_MODE_ABS_PINNED_HARD);
+        } else {
                 tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1);
+        }
 
         /*
          * Reset to make sure next tick stop doesn't get fooled by past
@@ -802,7 +804,8 @@ static void tick_nohz_stop_tick(struct tick_sched *ts, int cpu)
         }
 
         if (ts->nohz_mode == NOHZ_MODE_HIGHRES) {
-                hrtimer_start(&ts->sched_timer, tick, HRTIMER_MODE_ABS_PINNED);
+                hrtimer_start(&ts->sched_timer, tick,
+                              HRTIMER_MODE_ABS_PINNED_HARD);
         } else {
                 hrtimer_set_expires(&ts->sched_timer, tick);
                 tick_program_event(tick, 1);
@@ -1230,7 +1233,7 @@ static void tick_nohz_switch_to_nohz(void)
          * Recycle the hrtimer in ts, so we can share the
          * hrtimer_forward with the highres code.
          */
-        hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+        hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
         /* Get the next period */
         next = tick_init_jiffy_update();
 
@@ -1327,7 +1330,7 @@ void tick_setup_sched_timer(void)
         /*
          * Emulate tick processing via per-CPU hrtimers:
          */
-        hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+        hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
         ts->sched_timer.function = tick_sched_timer;
 
         /* Get the next period (per-CPU) */
@@ -1342,7 +1345,7 @@ void tick_setup_sched_timer(void)
         }
 
         hrtimer_forward(&ts->sched_timer, now, tick_period);
-        hrtimer_start_expires(&ts->sched_timer, HRTIMER_MODE_ABS_PINNED);
+        hrtimer_start_expires(&ts->sched_timer, HRTIMER_MODE_ABS_PINNED_HARD);
         tick_nohz_activate(ts, NOHZ_MODE_HIGHRES);
 }
 #endif /* HIGH_RES_TIMERS */