ACPI: processor: Use CPUIDLE_FLAG_TIMER_STOP

Make acpi_processor_idle use the common broadcast code, there's no
reason not to. This also removes some RCU usage after
rcu_idle_enter().

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 71a30b0d0f05a9cf75cafd20e178accd15ce3141..01ea986b61973c42118719ef28570f1dd2f336f0 100644 (file)
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -161,18 +161,10 @@ static void lapic_timer_propagate_broadcast(struct acpi_processor *pr)
 }
 
 /* Power(C) State timer broadcast control */
-static void lapic_timer_state_broadcast(struct acpi_processor *pr,
-                                      struct acpi_processor_cx *cx,
-                                      int broadcast)
+static bool lapic_timer_needs_broadcast(struct acpi_processor *pr,
+                                       struct acpi_processor_cx *cx)
 {
-       int state = cx - pr->power.states;
-
-       if (state >= pr->power.timer_broadcast_on_state) {
-               if (broadcast)
-                       tick_broadcast_enter();
-               else
-                       tick_broadcast_exit();
-       }
+       return cx - pr->power.states >= pr->power.timer_broadcast_on_state;
 }
 
 #else
@@ -180,9 +172,9 @@ static void lapic_timer_state_broadcast(struct acpi_processor *pr,
 static void lapic_timer_check_state(int state, struct acpi_processor *pr,
                                   struct acpi_processor_cx *cstate) { }
 static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { }
-static void lapic_timer_state_broadcast(struct acpi_processor *pr,
-                                      struct acpi_processor_cx *cx,
-                                      int broadcast)
+
+static bool lapic_timer_needs_broadcast(struct acpi_processor *pr,
+                                       struct acpi_processor_cx *cx)
 {
 }
 
@@ -568,20 +560,12 @@ static DEFINE_RAW_SPINLOCK(c3_lock);
  * acpi_idle_enter_bm - enters C3 with proper BM handling
  * @pr: Target processor
  * @cx: Target state context
- * @timer_bc: Whether or not to change timer mode to broadcast
  */
 static void acpi_idle_enter_bm(struct acpi_processor *pr,
-                              struct acpi_processor_cx *cx, bool timer_bc)
+                              struct acpi_processor_cx *cx)
 {
        acpi_unlazy_tlb(smp_processor_id());
 
-       /*
-        * Must be done before busmaster disable as we might need to
-        * access HPET !
-        */
-       if (timer_bc)
-               lapic_timer_state_broadcast(pr, cx, 1);
-
        /*
         * disable bus master
         * bm_check implies we need ARB_DIS
@@ -609,9 +593,6 @@ static void acpi_idle_enter_bm(struct acpi_processor *pr,
                c3_cpu_count--;
                raw_spin_unlock(&c3_lock);
        }
-
-       if (timer_bc)
-               lapic_timer_state_broadcast(pr, cx, 0);
 }
 
 static int acpi_idle_enter(struct cpuidle_device *dev,
@@ -630,7 +611,7 @@ static int acpi_idle_enter(struct cpuidle_device *dev,
                        cx = per_cpu(acpi_cstate[index], dev->cpu);
                } else if (cx->type == ACPI_STATE_C3 && pr->flags.bm_check) {
                        if (cx->bm_sts_skip || !acpi_idle_bm_check()) {
-                               acpi_idle_enter_bm(pr, cx, true);
+                               acpi_idle_enter_bm(pr, cx);
                                return index;
                        } else if (drv->safe_state_index >= 0) {
                                index = drv->safe_state_index;
@@ -642,15 +623,11 @@ static int acpi_idle_enter(struct cpuidle_device *dev,
                }
        }
 
-       lapic_timer_state_broadcast(pr, cx, 1);
-
        if (cx->type == ACPI_STATE_C3)
                ACPI_FLUSH_CPU_CACHE();
 
        acpi_idle_do_entry(cx);
 
-       lapic_timer_state_broadcast(pr, cx, 0);
-
        return index;
 }
 
@@ -666,7 +643,7 @@ static int acpi_idle_enter_s2idle(struct cpuidle_device *dev,
                        return 0;
 
                if (pr->flags.bm_check) {
-                       acpi_idle_enter_bm(pr, cx, false);
+                       acpi_idle_enter_bm(pr, cx);
                        return 0;
                } else {
                        ACPI_FLUSH_CPU_CACHE();
@@ -682,6 +659,7 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
 {
        int i, count = ACPI_IDLE_STATE_START;
        struct acpi_processor_cx *cx;
+       struct cpuidle_state *state;
 
        if (max_cstate == 0)
                max_cstate = 1;
@@ -694,6 +672,11 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
 
                per_cpu(acpi_cstate[count], dev->cpu) = cx;
 
+               if (lapic_timer_needs_broadcast(pr, cx)) {
+                       state = &acpi_idle_driver.states[count];
+                       state->flags |= CPUIDLE_FLAG_TIMER_STOP;
+               }
+
                count++;
                if (count == CPUIDLE_STATE_MAX)
                        break;