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=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 A3E5DC38A29 for ; Sat, 18 Apr 2020 16:16:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7AD54206D9 for ; Sat, 18 Apr 2020 16:16:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="AEV0Q8nz" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726707AbgDRQQA (ORCPT ); Sat, 18 Apr 2020 12:16:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726069AbgDRQQA (ORCPT ); Sat, 18 Apr 2020 12:16:00 -0400 Received: from mail-pg1-x544.google.com (mail-pg1-x544.google.com [IPv6:2607:f8b0:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0CDD6C061A0F for ; Sat, 18 Apr 2020 09:16:00 -0700 (PDT) Received: by mail-pg1-x544.google.com with SMTP id 188so2736240pgj.13 for ; Sat, 18 Apr 2020 09:16:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=ynPs9yCTFEYeEFPuAm4M1vFpAEJsfkM86gMqu119GEg=; b=AEV0Q8nz4bM1mFjWrAqmRb5Uk76KbAox9kQ7IFQwCyOcg4niMOPIZarlOuziLxs9sT 8eBlbsdiLAuvQaOOsmzd6Rd1IBXUTlnsU8eU+7EPHfuc1k+5NDECbQrewH26RG6Q+rEP DorsroP/2q/HaX3wOR3bvW5Icj2qS8Z6O1hCA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=ynPs9yCTFEYeEFPuAm4M1vFpAEJsfkM86gMqu119GEg=; b=PiZO7nRDx4yNBJrTlsSUDM1TkSY40Tky8GG24vR/pJM9FwqIYHnqtverxW5oeK5bWj 948HTlwJyd4Hpa4SbkmYpgtFm30VLMfWxkhLas9sg1ti+wfu/lDfN6z0mjAWiWqmaMTx D5ueTJm54kRelJoP6YLacuRDXjFx9iMSxHmnra155KER0g7f0XcCdzq/rpzHAVd21M0u 6iCDAJ3YWbsCgmH0I/dRZR14NzyAr9MwXV0JV/26OtQXqL/0n2I6Br1QKMNY3LOTIWTJ s1mQZcEi5tUxiBvO/gzDGBw4Yf0I175VgVtrBUg73PzSg0rMvp4lXSNorzjA1cjCXiCo CDPg== X-Gm-Message-State: AGi0PubDsf89FJ6b/rLON2exa3kEE7tX4/xxMd24nhtucmLvmapJPQD3 zDQEdFFGCB9Pf4k2fNn+/KrtXg== X-Google-Smtp-Source: APiQypLAxdOBnUjU+81Bxrc2gydUAnUtyWqhVEM5QLe5VrX10ZsCZcUUMHZw/dppb11GOcsoMh27YA== X-Received: by 2002:a65:6704:: with SMTP id u4mr8689747pgf.263.1587226559547; Sat, 18 Apr 2020 09:15:59 -0700 (PDT) Received: from localhost ([2620:15c:202:1:4fff:7a6b:a335:8fde]) by smtp.gmail.com with ESMTPSA id s129sm9456896pfb.3.2020.04.18.09.15.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 18 Apr 2020 09:15:58 -0700 (PDT) Date: Sat, 18 Apr 2020 09:15:57 -0700 From: Matthias Kaehlcke To: Douglas Anderson Cc: bjorn.andersson@linaro.org, agross@kernel.org, swboyd@chromium.org, mkshah@codeaurora.org, Evan Green , Srinivas Rao L , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] soc: qcom: rpmh: Dirt can only make you dirtier, not cleaner Message-ID: <20200418161557.GF199755@google.com> References: <20200417141531.1.Ia4b74158497213eabad7c3d474c50bfccb3f342e@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200417141531.1.Ia4b74158497213eabad7c3d474c50bfccb3f342e@changeid> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 17, 2020 at 02:15:47PM -0700, Douglas Anderson wrote: > Adding an item into the cache should never be able to make the cache > cleaner. Use "|=" rather than "=" to update the dirty flag. > > Fixes: bb7000677a1b ("soc: qcom: rpmh: Update dirty flag only when data changes") > Reported-by: Stephen Boyd > Signed-off-by: Douglas Anderson > --- > > drivers/soc/qcom/rpmh.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c > index 3abbb08cd6e1..d1626a1328d7 100644 > --- a/drivers/soc/qcom/rpmh.c > +++ b/drivers/soc/qcom/rpmh.c > @@ -151,10 +151,10 @@ static struct cache_req *cache_rpm_request(struct rpmh_ctrlr *ctrlr, > break; > } > > - ctrlr->dirty = (req->sleep_val != old_sleep_val || > - req->wake_val != old_wake_val) && > - req->sleep_val != UINT_MAX && > - req->wake_val != UINT_MAX; > + ctrlr->dirty |= (req->sleep_val != old_sleep_val || > + req->wake_val != old_wake_val) && > + req->sleep_val != UINT_MAX && > + req->wake_val != UINT_MAX; > > unlock: > spin_unlock_irqrestore(&ctrlr->cache_lock, flags); Reviewed-by: Matthias Kaehlcke