From 87ebbb8c612b1214f227ebb8f25442c6d163e802 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Mon, 6 Dec 2021 15:29:51 +0300 Subject: [PATCH] ACPI: processor: idle: Only flush cache on entering C3 According to ACPI 6.4, Section 8.2, CPU cache flushing required on entering the C3 power state. Avoid flushing the cache on entering other C-states. Signed-off-by: Kirill A. Shutemov [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki --- drivers/acpi/processor_idle.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 4b906bb527e8..d94794bc269e 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -565,7 +565,8 @@ static int acpi_idle_play_dead(struct cpuidle_device *dev, int index) { struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); - ACPI_FLUSH_CPU_CACHE(); + if (cx->type == ACPI_STATE_C3) + ACPI_FLUSH_CPU_CACHE(); while (1) { -- 2.20.1