From aa6b43d57f995f6eec0e9e744dcb200e09ecb8e0 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 15 Sep 2020 12:31:58 +0200 Subject: 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) Reported-by: Borislav Petkov Tested-by: Borislav Petkov Signed-off-by: Rafael J. Wysocki --- drivers/acpi/processor_idle.c | 47 ++++++++++++++----------------------------- 1 file changed, 15 insertions(+), 32 deletions(-) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 71a30b0d0f05..01ea986b6197 100644 --- 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; -- cgit v1.2.3