From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751273AbbBKDnC (ORCPT ); Tue, 10 Feb 2015 22:43:02 -0500 Received: from v094114.home.net.pl ([79.96.170.134]:61259 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750759AbbBKDm7 (ORCPT ); Tue, 10 Feb 2015 22:42:59 -0500 From: "Rafael J. Wysocki" To: Thomas Gleixner Cc: Peter Zijlstra , Alan Cox , "Li, Aubrey" , LKML , Linux PM list , ACPI Devel Maling List , Kristen Carlson Accardi , John Stultz , Len Brown Subject: [PATCH 6/6] ACPI / idle: Implement ->enter_freeze callback routine Date: Wed, 11 Feb 2015 05:04:57 +0100 Message-ID: <2622717.o1c258ItSq@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.16.0-rc5+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <8292243.ibkmfVtXac@vostro.rjw.lan> References: <8292243.ibkmfVtXac@vostro.rjw.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki Add an ->enter_freeze callback routine, acpi_idle_enter_freeze(), to the ACPI cpuidle driver and point ->enter_freeze to it for all the C2-type and C3-type states that don't need to fall back to C1 (which may be halt-induced and that will re-enable interrupts on exit from idle, which ->enter_freeze cannot do). Signed-off-by: Rafael J. Wysocki --- drivers/acpi/processor_idle.c | 48 +++++++++++++++++++++++++++++++++++------- 1 file changed, 40 insertions(+), 8 deletions(-) Index: linux-pm/drivers/acpi/processor_idle.c =================================================================== --- linux-pm.orig/drivers/acpi/processor_idle.c +++ linux-pm/drivers/acpi/processor_idle.c @@ -732,9 +732,8 @@ static int acpi_idle_play_dead(struct cp static bool acpi_idle_fallback_to_c1(struct acpi_processor *pr) { - return IS_ENABLED(CONFIG_HOTPLUG_CPU) && num_online_cpus() > 1 && - !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED) && - !pr->flags.has_cst; + return IS_ENABLED(CONFIG_HOTPLUG_CPU) && !pr->flags.has_cst && + !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED); } static int c3_cpu_count; @@ -744,9 +743,10 @@ static DEFINE_RAW_SPINLOCK(c3_lock); * acpi_idle_enter_bm - enters C3 with proper BM handling * @pr: Target processor * @cx: Target state context + * @timer_bc: Whether or not to change timer mode to broadcast */ static void acpi_idle_enter_bm(struct acpi_processor *pr, - struct acpi_processor_cx *cx) + struct acpi_processor_cx *cx, bool timer_bc) { acpi_unlazy_tlb(smp_processor_id()); @@ -754,7 +754,8 @@ static void acpi_idle_enter_bm(struct ac * Must be done before busmaster disable as we might need to * access HPET ! */ - lapic_timer_state_broadcast(pr, cx, 1); + if (timer_bc) + lapic_timer_state_broadcast(pr, cx, 1); /* * disable bus master @@ -784,7 +785,8 @@ static void acpi_idle_enter_bm(struct ac raw_spin_unlock(&c3_lock); } - lapic_timer_state_broadcast(pr, cx, 0); + if (timer_bc) + lapic_timer_state_broadcast(pr, cx, 0); } static int acpi_idle_enter(struct cpuidle_device *dev, @@ -798,12 +800,12 @@ static int acpi_idle_enter(struct cpuidl return -EINVAL; if (cx->type != ACPI_STATE_C1) { - if (acpi_idle_fallback_to_c1(pr)) { + if (acpi_idle_fallback_to_c1(pr) && num_online_cpus() > 1) { index = CPUIDLE_DRIVER_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); + acpi_idle_enter_bm(pr, cx, true); return index; } else if (drv->safe_state_index >= 0) { index = drv->safe_state_index; @@ -827,6 +829,27 @@ static int acpi_idle_enter(struct cpuidl return index; } +static void acpi_idle_enter_freeze(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); + + if (cx->type == ACPI_STATE_C3) { + struct acpi_processor *pr = __this_cpu_read(processors); + + if (unlikely(!pr)) + return; + + if (pr->flags.bm_check) { + acpi_idle_enter_bm(pr, cx, false); + return; + } else { + ACPI_FLUSH_CPU_CACHE(); + } + } + acpi_idle_do_entry(cx); +} + struct cpuidle_driver acpi_idle_driver = { .name = "acpi_idle", .owner = THIS_MODULE, @@ -925,6 +948,15 @@ static int acpi_processor_setup_cpuidle_ state->enter_dead = acpi_idle_play_dead; drv->safe_state_index = count; } + /* + * Halt-induced C1 is not good for ->enter_freeze, because it + * re-enables interrupts on exit. Moreover, C1 is generally not + * particularly interesting from the suspend-to-idle angle, so + * avoid C1 and the situations in which we may need to fall back + * to it altogether. + */ + if (cx->type != ACPI_STATE_C1 && !acpi_idle_fallback_to_c1(pr)) + state->enter_freeze = acpi_idle_enter_freeze; count++; if (count == CPUIDLE_STATE_MAX)