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path: root/drivers/acpi/processor_idle.c
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Diffstat (limited to 'drivers/acpi/processor_idle.c')
-rw-r--r--drivers/acpi/processor_idle.c61
1 files changed, 49 insertions, 12 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 70d8a6ec0920..807b0df308f1 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -169,15 +169,11 @@ acpi_processor_power_activate(struct acpi_processor *pr,
static void acpi_safe_halt(void)
{
- int polling = test_thread_flag(TIF_POLLING_NRFLAG);
- if (polling) {
- clear_thread_flag(TIF_POLLING_NRFLAG);
- smp_mb__after_clear_bit();
- }
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ smp_mb__after_clear_bit();
if (!need_resched())
safe_halt();
- if (polling)
- set_thread_flag(TIF_POLLING_NRFLAG);
+ set_thread_flag(TIF_POLLING_NRFLAG);
}
static atomic_t c3_cpu_count;
@@ -278,6 +274,17 @@ static void acpi_processor_idle(void)
}
}
+#ifdef CONFIG_HOTPLUG_CPU
+ /*
+ * Check for P_LVL2_UP flag before entering C2 and above on
+ * an SMP system. We do it here instead of doing it at _CST/P_LVL
+ * detection phase, to work cleanly with logical CPU hotplug.
+ */
+ if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
+ !pr->flags.has_cst && !acpi_fadt.plvl2_up)
+ cx = &pr->power.states[ACPI_STATE_C1];
+#endif
+
cx->usage++;
/*
@@ -285,6 +292,16 @@ static void acpi_processor_idle(void)
* ------
* Invoke the current Cx state to put the processor to sleep.
*/
+ if (cx->type == ACPI_STATE_C2 || cx->type == ACPI_STATE_C3) {
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ smp_mb__after_clear_bit();
+ if (need_resched()) {
+ set_thread_flag(TIF_POLLING_NRFLAG);
+ local_irq_enable();
+ return;
+ }
+ }
+
switch (cx->type) {
case ACPI_STATE_C1:
@@ -317,6 +334,7 @@ static void acpi_processor_idle(void)
t2 = inl(acpi_fadt.xpm_tmr_blk.address);
/* Re-enable interrupts */
local_irq_enable();
+ set_thread_flag(TIF_POLLING_NRFLAG);
/* Compute time (ticks) that we were actually asleep */
sleep_ticks =
ticks_elapsed(t1, t2) - cx->latency_ticks - C2_OVERHEAD;
@@ -356,6 +374,7 @@ static void acpi_processor_idle(void)
/* Re-enable interrupts */
local_irq_enable();
+ set_thread_flag(TIF_POLLING_NRFLAG);
/* Compute time (ticks) that we were actually asleep */
sleep_ticks =
ticks_elapsed(t1, t2) - cx->latency_ticks - C3_OVERHEAD;
@@ -368,6 +387,15 @@ static void acpi_processor_idle(void)
next_state = pr->power.state;
+#ifdef CONFIG_HOTPLUG_CPU
+ /* Don't do promotion/demotion */
+ if ((cx->type == ACPI_STATE_C1) && (num_online_cpus() > 1) &&
+ !pr->flags.has_cst && !acpi_fadt.plvl2_up) {
+ next_state = cx;
+ goto end;
+ }
+#endif
+
/*
* Promotion?
* ----------
@@ -534,6 +562,15 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
pr->power.states[ACPI_STATE_C0].valid = 1;
pr->power.states[ACPI_STATE_C1].valid = 1;
+#ifndef CONFIG_HOTPLUG_CPU
+ /*
+ * Check for P_LVL2_UP flag before entering C2 and above on
+ * an SMP system.
+ */
+ if ((num_online_cpus() > 1) && !acpi_fadt.plvl2_up)
+ return_VALUE(-ENODEV);
+#endif
+
/* determine C2 and C3 address from pblk */
pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4;
pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5;
@@ -690,7 +727,7 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
/* Validate number of power states discovered */
if (pr->power.count < 2)
- status = -ENODEV;
+ status = -EFAULT;
end:
acpi_os_free(buffer.pointer);
@@ -841,11 +878,11 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
* this function */
result = acpi_processor_get_power_info_cst(pr);
- if ((result) || (acpi_processor_power_verify(pr) < 2)) {
+ if (result == -ENODEV)
result = acpi_processor_get_power_info_fadt(pr);
- if ((result) || (acpi_processor_power_verify(pr) < 2))
- result = acpi_processor_get_power_info_default_c1(pr);
- }
+
+ if ((result) || (acpi_processor_power_verify(pr) < 2))
+ result = acpi_processor_get_power_info_default_c1(pr);
/*
* Set Default Policy