diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/acpi/processor_idle.c | 69 |
1 files changed, 49 insertions, 20 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 9ec504067f98..7ecb90e90afd 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -558,22 +558,43 @@ static DEFINE_RAW_SPINLOCK(c3_lock); /** * acpi_idle_enter_bm - enters C3 with proper BM handling + * @drv: cpuidle driver * @pr: Target processor * @cx: Target state context + * @index: index of target state */ -static void acpi_idle_enter_bm(struct acpi_processor *pr, - struct acpi_processor_cx *cx) +static int acpi_idle_enter_bm(struct cpuidle_driver *drv, + struct acpi_processor *pr, + struct acpi_processor_cx *cx, + int index) { + static struct acpi_processor_cx safe_cx = { + .entry_method = ACPI_CSTATE_HALT, + }; + /* * disable bus master * bm_check implies we need ARB_DIS * bm_control implies whether we can do ARB_DIS * - * That leaves a case where bm_check is set and bm_control is - * not set. In that case we cannot do much, we enter C3 - * without doing anything. + * That leaves a case where bm_check is set and bm_control is not set. + * In that case we cannot do much, we enter C3 without doing anything. */ - if (pr->flags.bm_control) { + bool dis_bm = pr->flags.bm_control; + + /* If we can skip BM, demote to a safe state. */ + if (!cx->bm_sts_skip && acpi_idle_bm_check()) { + dis_bm = false; + index = drv->safe_state_index; + if (index >= 0) { + cx = this_cpu_read(acpi_cstate[index]); + } else { + cx = &safe_cx; + index = -EBUSY; + } + } + + if (dis_bm) { raw_spin_lock(&c3_lock); c3_cpu_count++; /* Disable bus master arbitration when all CPUs are in C3 */ @@ -582,15 +603,21 @@ static void acpi_idle_enter_bm(struct acpi_processor *pr, raw_spin_unlock(&c3_lock); } + rcu_idle_enter(); + acpi_idle_do_entry(cx); + rcu_idle_exit(); + /* Re-enable bus master arbitration */ - if (pr->flags.bm_control) { + if (dis_bm) { raw_spin_lock(&c3_lock); acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); c3_cpu_count--; raw_spin_unlock(&c3_lock); } + + return index; } static int acpi_idle_enter(struct cpuidle_device *dev, @@ -604,20 +631,13 @@ static int acpi_idle_enter(struct cpuidle_device *dev, return -EINVAL; if (cx->type != ACPI_STATE_C1) { + if (cx->type == ACPI_STATE_C3 && pr->flags.bm_check) + return acpi_idle_enter_bm(drv, pr, cx, index); + + /* C2 to C1 demotion. */ if (acpi_idle_fallback_to_c1(pr) && num_online_cpus() > 1) { index = ACPI_IDLE_STATE_START; 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); - return index; - } else if (drv->safe_state_index >= 0) { - index = drv->safe_state_index; - cx = per_cpu(acpi_cstate[index], dev->cpu); - } else { - acpi_safe_halt(); - return -EBUSY; - } } } @@ -641,7 +661,13 @@ static int acpi_idle_enter_s2idle(struct cpuidle_device *dev, return 0; if (pr->flags.bm_check) { - acpi_idle_enter_bm(pr, cx); + u8 bm_sts_skip = cx->bm_sts_skip; + + /* Don't check BM_STS, do an unconditional ARB_DIS for S2IDLE */ + cx->bm_sts_skip = 1; + acpi_idle_enter_bm(drv, pr, cx, index); + cx->bm_sts_skip = bm_sts_skip; + return 0; } else { ACPI_FLUSH_CPU_CACHE(); @@ -674,8 +700,11 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr, if (lapic_timer_needs_broadcast(pr, cx)) state->flags |= CPUIDLE_FLAG_TIMER_STOP; - if (cx->type == ACPI_STATE_C3) + if (cx->type == ACPI_STATE_C3) { state->flags |= CPUIDLE_FLAG_TLB_FLUSHED; + if (pr->flags.bm_check) + state->flags |= CPUIDLE_FLAG_RCU_IDLE; + } count++; if (count == CPUIDLE_STATE_MAX) |