From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.0 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 ADC21C433DF for ; Sat, 22 Aug 2020 16:22:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7ABC32072D for ; Sat, 22 Aug 2020 16:22:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="T9fWBZtp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728445AbgHVQWY (ORCPT ); Sat, 22 Aug 2020 12:22:24 -0400 Received: from mail29.static.mailgun.info ([104.130.122.29]:42525 "EHLO mail29.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728255AbgHVQWY (ORCPT ); Sat, 22 Aug 2020 12:22:24 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1598113343; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=V4rACd0qNQCX7VgMID8KO6aura52vGajef+rE/jCsbI=; b=T9fWBZtpPPQZQ7PNQkCuHNgpGH93n9J0f3WlQWIMWEq1X0loGUuWytcP/G7FLFAvpNLahGZD 6aVKq/eb7GG2rsW/kNxuDwMmGQ4QgjjiGqjfvnYCJaM8QBiAmmn4eBPTF8JsqZco0pPZ+rhX HQPeoOScnveF2rfvHENtDYS66+Q= X-Mailgun-Sending-Ip: 104.130.122.29 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n05.prod.us-east-1.postgun.com with SMTP id 5f41461d91f122588b73f0a3 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Sat, 22 Aug 2020 16:21:49 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 79539C433A0; Sat, 22 Aug 2020 16:21:48 +0000 (UTC) Received: from [192.168.29.129] (unknown [49.36.0.88]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: mkshah) by smtp.codeaurora.org (Postfix) with ESMTPSA id 6334BC433C6; Sat, 22 Aug 2020 16:21:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 6334BC433C6 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=none smtp.mailfrom=mkshah@codeaurora.org Subject: Re: [PATCH 1/2] Revert "drivers: qcom: rpmh-rsc: Use rcuidle tracepoints for rpmh" To: Stephen Boyd , agross@kernel.org, bjorn.andersson@linaro.org Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, ulf.hansson@linaro.org, dianders@chromium.org, rnayak@codeaurora.org, ilina@codeaurora.org, lsrao@codeaurora.org, Sai Prakash Ranjan , John Stultz , Stephen Rothwell References: <1597831670-17401-1-git-send-email-mkshah@codeaurora.org> <1597831670-17401-2-git-send-email-mkshah@codeaurora.org> <159786026353.334488.6206471069270174090@swboyd.mtv.corp.google.com> From: Maulik Shah Message-ID: <0af1ced1-7415-4627-968a-53cf6cf07bad@codeaurora.org> Date: Sat, 22 Aug 2020 21:51:40 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <159786026353.334488.6206471069270174090@swboyd.mtv.corp.google.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-GB Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 8/19/2020 11:34 PM, Stephen Boyd wrote: > Quoting Maulik Shah (2020-08-19 03:07:49) >> This change was done based on an test results of unmerged series of >> adding RSC power domain and using .power_off callback of genpd to >> invoke rpmh_flush(). > Perhaps: > > Commit efde2659b0fe ("drivers: qcom: rpmh-rsc: Use rcuidle tracepoints > for rpmh") was written to fix a bug seen in an unmerged series that > implemented a struct generic_pm_domain::power_off() callback calling > rpmh_flush(). See stack trace below. Sure i will update in v2. > >> Call trace: >> dump_backtrace+0x0/0x174 >> show_stack+0x20/0x2c >> dump_stack+0xc8/0x124 >> lockdep_rcu_suspicious+0xe4/0x104 >> __tcs_buffer_write+0x230/0x2d0 >> rpmh_rsc_write_ctrl_data+0x210/0x270 >> rpmh_flush+0x84/0x24c >> rpmh_domain_power_off+0x78/0x98 >> _genpd_power_off+0x40/0xc0 >> genpd_power_off+0x168/0x208 >> >> Later the final merged solution is to use CPU PM notification to invoke >> rpmh_flush() and .power_off callback of genpd is not implemented in the >> driver. > I'd also add: > > CPU PM notifiers are run with RCU enabled/watching (see cpu_pm_notify() > and how it calls rcu_irq_enter_irqson() before calling the notifiers). Sure i will update in v2. > >> Remove this change since RCU will not be idle during CPU PM notifications >> hence not required to use _rcuidle tracepoint. Using _rcuidle tracepoint >> prevented rpmh driver to be loadable module as these are not exported >> symbols. >> >> This reverts commit efde2659b0fe835732047357b2902cca14f054d9. >> >> Cc: Sai Prakash Ranjan >> Cc: John Stultz >> Cc: Stephen Rothwell >> Signed-off-by: Maulik Shah >> --- > Otherwise > > Reviewed-by: Stephen Boyd Thanks for the review. Thanks, Maulik -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation