Commit 3c89857a authored by Kirill A. Shutemov's avatar Kirill A. Shutemov Committed by Rafael J. Wysocki
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ACPI: PM: Remove redundant cache flushing 



ACPICA code takes care about cache flushing on S1/S2/S3 in
acpi_hw_extended_sleep() and acpi_hw_legacy_sleep().

acpi_suspend_enter() calls into ACPICA code via acpi_enter_sleep_state()
for S1 or x86_acpi_suspend_lowlevel() for S3.

acpi_sleep_prepare() call tree:
  __acpi_pm_prepare()
    acpi_pm_prepare()
      acpi_suspend_ops::prepare_late()
      acpi_hibernation_ops::pre_snapshot()
      acpi_hibernation_ops::prepare()
    acpi_suspend_begin_old()
      acpi_suspend_begin_old::begin()
  acpi_hibernation_begin_old()
    acpi_hibernation_ops_old::acpi_hibernation_begin_old()
  acpi_power_off_prepare()
    pm_power_off_prepare()

Hibernation (S4) and Power Off (S5) don't require cache flushing, so
the only interesting callsites are acpi_suspend_ops::prepare_late()
and acpi_suspend_begin_old::begin(). Both of them have cache flush
on ->enter() operation in acpi_suspend_enter().

Remove redundant ACPI_FLUSH_CPU_CACHE() in acpi_sleep_prepare() and
acpi_suspend_enter().

Signed-off-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 53d01e20

drivers/acpi/sleep.c

+0 −3
Original line number Diff line number Diff line
@@ -73,7 +73,6 @@ static int acpi_sleep_prepare(u32 acpi_state) 
		acpi_set_waking_vector(acpi_wakeup_address);



	}

	ACPI_FLUSH_CPU_CACHE();

#endif

	pr_info("Preparing to enter system sleep state S%d\n", acpi_state);

	acpi_enable_wakeup_devices(acpi_state);
@@ -566,8 +565,6 @@ static int acpi_suspend_enter(suspend_state_t pm_state) 
	u32 acpi_state = acpi_target_sleep_state;

	int error;



	ACPI_FLUSH_CPU_CACHE();



	trace_suspend_resume(TPS("acpi_suspend"), acpi_state, true);

	switch (acpi_state) {

	case ACPI_STATE_S1: