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ACPI: processor: Use CPUIDLE_FLAG_TIMER_STOP

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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>
This commit is contained in:
Peter Zijlstra 2020-09-15 12:31:58 +02:00 committed by Rafael J. Wysocki
parent 856deb866d
commit aa6b43d57f
1 changed files with 15 additions and 32 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

47
drivers/acpi/processor_idle.c
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@ -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;