[PATCH 5/5] ACPI / cpuidle: Drop flags.bm_check tests from acpi_idle_enter_bm()

From: Rafael J. Wysocki
Date: Thu Jan 29 2015 - 13:09:11 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Since acpi_idle_enter_bm() is only used if flags.bm_check is set for
the given acpi_processor object, it doesn't make sense to check that
flag in there.

For this reason, drop flags.bm_check tests (and some code depending
on them) from acpi_idle_enter_bm().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/acpi/processor_idle.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

Index: linux-pm/drivers/acpi/processor_idle.c
===================================================================
--- linux-pm.orig/drivers/acpi/processor_idle.c
+++ linux-pm/drivers/acpi/processor_idle.c
@@ -842,28 +842,25 @@ static int acpi_idle_enter_bm(struct cpu
/*
* disable bus master
* bm_check implies we need ARB_DIS
- * !bm_check implies we need cache flush
* 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.
*/
- if (pr->flags.bm_check && pr->flags.bm_control) {
+ if (pr->flags.bm_control) {
raw_spin_lock(&c3_lock);
c3_cpu_count++;
/* Disable bus master arbitration when all CPUs are in C3 */
if (c3_cpu_count == num_online_cpus())
acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1);
raw_spin_unlock(&c3_lock);
- } else if (!pr->flags.bm_check) {
- ACPI_FLUSH_CPU_CACHE();
}

acpi_idle_do_entry(cx);

/* Re-enable bus master arbitration */
- if (pr->flags.bm_check && pr->flags.bm_control) {
+ if (pr->flags.bm_control) {
raw_spin_lock(&c3_lock);
acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0);
c3_cpu_count--;

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