From patchwork Mon Oct 12 22:34:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lina Iyer X-Patchwork-Id: 285062 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 7189AC433E7 for ; Mon, 12 Oct 2020 22:34:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3572620797 for ; Mon, 12 Oct 2020 22:34:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="X1eDrmCH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390162AbgJLWej (ORCPT ); Mon, 12 Oct 2020 18:34:39 -0400 Received: from m42-4.mailgun.net ([69.72.42.4]:59541 "EHLO m42-4.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389703AbgJLWei (ORCPT ); Mon, 12 Oct 2020 18:34:38 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1602542077; h=Content-Transfer-Encoding: MIME-Version: References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=XKpGBpZzmWhm7bXNsIqJEj46Bl1p8p5AhOlTFIJPcJ8=; b=X1eDrmCH3djjwBRFgbJB6IsL09EiV5A5xBXEhAxDckOZWHAUIcnVW9ySj6kKJiZtkIjod7zS GBtLEC+rH/fjxPHlVHNSKiDMR7yc1LiMvTpeihAqsB0WI0axQCLMDW0Dlr1w/tYPEq50XNIt n0CS2nOPx4t6cX/btGSe9bbejcY= X-Mailgun-Sending-Ip: 69.72.42.4 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n06.prod.us-east-1.postgun.com with SMTP id 5f84d9fb3711fec7b1a221d1 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Mon, 12 Oct 2020 22:34:35 GMT Sender: ilina=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 276BCC433F1; Mon, 12 Oct 2020 22:34:35 +0000 (UTC) Received: from codeaurora.org (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: ilina) by smtp.codeaurora.org (Postfix) with ESMTPSA id C8C77C433FF; Mon, 12 Oct 2020 22:34:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org C8C77C433FF Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=ilina@codeaurora.org From: Lina Iyer To: rjw@rjwysocki.net, ulf.hansson@linaro.org, linux-pm@vger.kernel.org Cc: linux-arm-msm@vger.kernel.org, Lina Iyer Subject: [PATCH 2/2] PM / Domains: use device's next wakeup to determine domain idle state Date: Mon, 12 Oct 2020 16:34:00 -0600 Message-Id: <20201012223400.23609-3-ilina@codeaurora.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201012223400.23609-1-ilina@codeaurora.org> References: <20201012223400.23609-1-ilina@codeaurora.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org If the device's next event is known, determine if it is worthwhile entering a domain idle state. To find the next wakeup, traverse a domain for all child devices and find out the earliest wakeup value. A parent domain's next wakeup is the earliest of all its child devices and domains. The next wakeup is specified by devices in the domains before they devices are suspended. Update the domain governor logic to determine if it is worthwhile to enter an idle state based on the next wakeup for the domain along with other existing constraints. Signed-off-by: Lina Iyer Reported-by: kernel test robot --- drivers/base/power/domain_governor.c | 83 ++++++++++++++++++++++++++-- include/linux/pm_domain.h | 1 + 2 files changed, 79 insertions(+), 5 deletions(-) diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c index 490ed7deb99a..77b4928aa389 100644 --- a/drivers/base/power/domain_governor.c +++ b/drivers/base/power/domain_governor.c @@ -117,6 +117,49 @@ static bool default_suspend_ok(struct device *dev) return td->cached_suspend_ok; } +static void update_domain_next_wakeup(struct generic_pm_domain *genpd, ktime_t now) +{ + ktime_t domain_wakeup = KTIME_MAX; + ktime_t next_wakeup; + struct pm_domain_data *pdd; + struct gpd_link *link; + + /* Find the earliest wakeup for all devices in the domain */ + list_for_each_entry(pdd, &genpd->dev_list, list_node) { + next_wakeup = READ_ONCE(pdd->dev->power.next_event); + if (next_wakeup != KTIME_MAX && !ktime_before(next_wakeup, now)) + if (ktime_before(next_wakeup, domain_wakeup)) + domain_wakeup = next_wakeup; + } + + /* Then find the earliest wakeup of from all the child domains */ + list_for_each_entry(link, &genpd->parent_links, parent_node) { + next_wakeup = link->child->next_wakeup; + if (next_wakeup != KTIME_MAX && !ktime_before(next_wakeup, now)) + if (ktime_before(next_wakeup, domain_wakeup)) + domain_wakeup = next_wakeup; + } + + genpd->next_wakeup = domain_wakeup; +} + +static bool next_wakeup_allows_state(struct generic_pm_domain *genpd, + unsigned int state, ktime_t now) +{ + s64 idle_time_ns, min_sleep_ns; + ktime_t domain_wakeup = genpd->next_wakeup; + + min_sleep_ns = genpd->states[state].power_off_latency_ns + + genpd->states[state].power_on_latency_ns + + genpd->states[state].residency_ns; + + idle_time_ns = ktime_to_ns(ktime_sub(domain_wakeup, now)); + if (idle_time_ns < min_sleep_ns) + return false; + + return true; +} + static bool __default_power_down_ok(struct dev_pm_domain *pd, unsigned int state) { @@ -210,6 +253,33 @@ static bool default_power_down_ok(struct dev_pm_domain *pd) { struct generic_pm_domain *genpd = pd_to_genpd(pd); struct gpd_link *link; + unsigned int state_idx; + ktime_t now = ktime_get(); + + /* + * Find the next wakeup from devices that can determine their own wakeup + * to find when the domain would wakeup and do it for every device down + * the hierarchy. It is not worth while to sleep if the state's residency + * cannot be met. + */ + update_domain_next_wakeup(genpd, now); + state_idx = genpd->state_count - 1; + if (genpd->next_wakeup != KTIME_MAX) { + /* Let's find out the deepest domain idle state, the devices prefer */ + while (state_idx >= 0) { + if (next_wakeup_allows_state(genpd, state_idx, now)) { + genpd->max_off_time_changed = true; + break; + } + state_idx--; + } + + if (state_idx < 0) { + state_idx = 0; + genpd->cached_power_down_ok = false; + goto done; + } + } if (!genpd->max_off_time_changed) { genpd->state_idx = genpd->cached_power_down_state_idx; @@ -228,17 +298,20 @@ static bool default_power_down_ok(struct dev_pm_domain *pd) genpd->max_off_time_ns = -1; genpd->max_off_time_changed = false; genpd->cached_power_down_ok = true; - genpd->state_idx = genpd->state_count - 1; - /* Find a state to power down to, starting from the deepest. */ - while (!__default_power_down_ok(pd, genpd->state_idx)) { - if (genpd->state_idx == 0) { + /* Find a state to power down to, starting from the state + * determined by the next wakeup. + */ + while (!__default_power_down_ok(pd, state_idx)) { + if (state_idx == 0) { genpd->cached_power_down_ok = false; break; } - genpd->state_idx--; + state_idx--; } +done: + genpd->state_idx = state_idx; genpd->cached_power_down_state_idx = genpd->state_idx; return genpd->cached_power_down_ok; } diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index ee11502a575b..9ea6f666967b 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -119,6 +119,7 @@ struct generic_pm_domain { unsigned int state); struct gpd_dev_ops dev_ops; s64 max_off_time_ns; /* Maximum allowed "suspended" time. */ + ktime_t next_wakeup; bool max_off_time_changed; bool cached_power_down_ok; bool cached_power_down_state_idx;