From patchwork Mon May 24 15:25:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 446676 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1E59C47085 for ; Mon, 24 May 2021 15:28:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 811CF6044F for ; Mon, 24 May 2021 15:28:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232929AbhEXP36 (ORCPT ); Mon, 24 May 2021 11:29:58 -0400 Received: from cloudserver094114.home.pl ([79.96.170.134]:51496 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233443AbhEXP3H (ORCPT ); Mon, 24 May 2021 11:29:07 -0400 Received: from localhost (127.0.0.1) (HELO v370.home.net.pl) by /usr/run/smtp (/usr/run/postfix/private/idea_relay_lmtp) via UNIX with SMTP (IdeaSmtpServer 2.0.5) id c768bedd6e9807ac; Mon, 24 May 2021 17:27:37 +0200 Received: from kreacher.localnet (89-64-80-49.dynamic.chello.pl [89.64.80.49]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by v370.home.net.pl (Postfix) with ESMTPSA id 4433766971F; Mon, 24 May 2021 17:27:36 +0200 (CEST) From: "Rafael J. Wysocki" To: Linux ACPI Cc: Linux PM , LKML , Zhang Rui , David Box , "Rafael J. Wysocki" , Dave Olsthoorn , Shujun Wang Subject: [PATCH v1 2/3] ACPI: power: Save the last known state of each power resource Date: Mon, 24 May 2021 17:25:23 +0200 Message-ID: <3126947.44csPzL39Z@kreacher> In-Reply-To: <2074778.irdbgypaU6@kreacher> References: <2074778.irdbgypaU6@kreacher> MIME-Version: 1.0 X-CLIENT-IP: 89.64.80.49 X-CLIENT-HOSTNAME: 89-64-80-49.dynamic.chello.pl X-VADE-SPAMSTATE: clean X-VADE-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduledrvdejledgledtucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecujffqoffgrffnpdggtffipffknecuuegrihhlohhuthemucduhedtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhvffufffkjghfggfgtgesthfuredttddtjeenucfhrhhomhepfdftrghfrggvlhculfdrucghhihsohgtkhhifdcuoehrjhifsehrjhifhihsohgtkhhirdhnvghtqeenucggtffrrghtthgvrhhnpedvjeelgffhiedukedtleekkedvudfggefhgfegjefgueekjeelvefggfdvledutdenucfkphepkeelrdeigedrkedtrdegleenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpeekledrieegrdektddrgeelpdhhvghlohepkhhrvggrtghhvghrrdhlohgtrghlnhgvthdpmhgrihhlfhhrohhmpedftfgrfhgrvghlucflrdcuhgihshhotghkihdfuceorhhjfiesrhhjfiihshhotghkihdrnhgvtheqpdhrtghpthhtoheplhhinhhugidqrggtphhisehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhinhhugidqphhmsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheplhhinhhugidqkhgvrhhnvghlsehvghgvrhdrkhgvrhhnvghlrdhorhhgpdhrtghpthhtoheprhhuihdriihhrghnghesihhnthgvlhdrtghomhdprhgtphhtthhopegurghvihgurdgvrdgsohigsehlihhnuhigrdhi nhhtvghlrdgtohhmpdhrtghpthhtoheprhgrfhgrvghlsehkvghrnhgvlhdrohhrghdprhgtphhtthhopegurghvvgessggvfigrrghrrdhmvgdprhgtphhtthhopeifshhjvddtfeeileesudeifedrtghomh X-DCC--Metrics: v370.home.net.pl 1024; Body=8 Fuz1=8 Fuz2=8 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Rafael J. Wysocki Currently, there are two ways to check the state of an ACPI power resource and they may not be consistent with each other. The first one is to evaluate the power resource's _STA object and the other one is to check its reference counter value. However, on some systems the value returned by _STA may not be consistent with the value of the power resource's reference counter (for example, on some systems it returns the same value every time for certain power resources). Moreover, evaluating _STA is unnecessary overhead for a power resource for which it has been evaluated already or whose state is otherwise known, because either the _ON or the _OFF method has been executed for it. For this reason, save the state of each power resource in its struct acpi_power_resource object and use the saved value whenever its state needs to be checked, except when its stats is unknown, in which case the _STA method is evaluated for it and the value returned by that method is saved as the last known state of the power resource. Moreover, drop the power resource _STA method evaluation from acpi_add_power_resource(), so as to avoid doing that unnecessarily for power resources that will never be used. Tested-by: Dave Olsthoorn Tested-by: Shujun Wang Signed-off-by: Rafael J. Wysocki --- drivers/acpi/power.c | 50 ++++++++++++++++++++++++++++++++------------------ 1 file changed, 32 insertions(+), 18 deletions(-) Index: linux-pm/drivers/acpi/power.c =================================================================== --- linux-pm.orig/drivers/acpi/power.c +++ linux-pm/drivers/acpi/power.c @@ -52,6 +52,7 @@ struct acpi_power_resource { u32 order; unsigned int ref_count; unsigned int users; + u8 state; bool wakeup_enabled; struct mutex resource_lock; struct list_head dependents; @@ -177,15 +178,12 @@ int acpi_extract_power_resources(union a return err; } -static int acpi_power_get_state(acpi_handle handle, u8 *state) +static int __get_state(acpi_handle handle, u8 *state) { acpi_status status = AE_OK; unsigned long long sta = 0; u8 cur_state; - if (!handle || !state) - return -EINVAL; - status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); if (ACPI_FAILURE(status)) return -ENODEV; @@ -199,6 +197,20 @@ static int acpi_power_get_state(acpi_han return 0; } +static int acpi_power_get_state(struct acpi_power_resource *resource, u8 *state) +{ + if (resource->state == ACPI_POWER_RESOURCE_STATE_UNKNOWN) { + int ret; + + ret = __get_state(resource->device.handle, &resource->state); + if (ret) + return ret; + } + + *state = resource->state; + return 0; +} + static int acpi_power_get_list_state(struct list_head *list, u8 *state) { struct acpi_power_resource_entry *entry; @@ -210,11 +222,10 @@ static int acpi_power_get_list_state(str /* The state of the list is 'on' IFF all resources are 'on'. */ list_for_each_entry(entry, list, node) { struct acpi_power_resource *resource = entry->resource; - acpi_handle handle = resource->device.handle; int result; mutex_lock(&resource->resource_lock); - result = acpi_power_get_state(handle, &cur_state); + result = acpi_power_get_state(resource, &cur_state); mutex_unlock(&resource->resource_lock); if (result) return result; @@ -347,8 +358,12 @@ static int __acpi_power_on(struct acpi_p acpi_status status = AE_OK; status = acpi_evaluate_object(resource->device.handle, "_ON", NULL, NULL); - if (ACPI_FAILURE(status)) + if (ACPI_FAILURE(status)) { + resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN; return -ENODEV; + } + + resource->state = ACPI_POWER_RESOURCE_STATE_ON; pr_debug("Power resource [%s] turned on\n", resource->name); @@ -400,8 +415,12 @@ static int __acpi_power_off(struct acpi_ status = acpi_evaluate_object(resource->device.handle, "_OFF", NULL, NULL); - if (ACPI_FAILURE(status)) + if (ACPI_FAILURE(status)) { + resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN; return -ENODEV; + } + + resource->state = ACPI_POWER_RESOURCE_STATE_OFF; pr_debug("Power resource [%s] turned off\n", resource->name); @@ -585,13 +604,12 @@ int acpi_power_wakeup_list_init(struct l list_for_each_entry(entry, list, node) { struct acpi_power_resource *resource = entry->resource; - acpi_handle handle = resource->device.handle; int result; u8 state; mutex_lock(&resource->resource_lock); - result = acpi_power_get_state(handle, &state); + result = acpi_power_get_state(resource, &state); if (result) { mutex_unlock(&resource->resource_lock); return result; @@ -915,7 +933,6 @@ int acpi_add_power_resource(acpi_handle struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object }; acpi_status status; int result; - u8 state; acpi_bus_get_device(handle, &device); if (device) @@ -942,13 +959,9 @@ int acpi_add_power_resource(acpi_handle resource->system_level = acpi_object.power_resource.system_level; resource->order = acpi_object.power_resource.resource_order; + resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN; - result = acpi_power_get_state(handle, &state); - if (result) - goto err; - - pr_info("%s [%s] (%s)\n", acpi_device_name(device), - acpi_device_bid(device), state ? "on" : "off"); + pr_info("%s [%s]\n", acpi_device_name(device), acpi_device_bid(device)); device->flags.match_driver = true; result = acpi_device_add(device, acpi_release_power_resource); @@ -980,7 +993,8 @@ void acpi_resume_power_resources(void) mutex_lock(&resource->resource_lock); - result = acpi_power_get_state(resource->device.handle, &state); + resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN; + result = acpi_power_get_state(resource, &state); if (result) { mutex_unlock(&resource->resource_lock); continue;