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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3E698C433EF for ; Tue, 12 Apr 2022 00:21:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241020AbiDLAX0 (ORCPT ); Mon, 11 Apr 2022 20:23:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33034 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240046AbiDLAXU (ORCPT ); Mon, 11 Apr 2022 20:23:20 -0400 Received: from mail-oi1-x230.google.com (mail-oi1-x230.google.com [IPv6:2607:f8b0:4864:20::230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C3FE41CFF3 for ; Mon, 11 Apr 2022 17:21:04 -0700 (PDT) Received: by mail-oi1-x230.google.com with SMTP id b188so17442318oia.13 for ; Mon, 11 Apr 2022 17:21:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:in-reply-to:references:from:user-agent:date:message-id :subject:to:cc; bh=y7Y1GROIPsSLxY9do07YZACd9MWDSI2F+M+lT+f9eTo=; b=HJgEFPK74D/NzNz5ewjQS1D3WZjnbn6QPFbqVtlhSvkdtZrvSBMTVSWXksPTipI0T0 uIqntfRaCN+XM2SobWYamTU+fzXI4do20kvZmAFLXkApFfG0I0RWihEspBxiqL5Ohv9S RHrhVCX3aEVON9iRfWjDEisKAVzxYtFIOGtyk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:in-reply-to:references:from :user-agent:date:message-id:subject:to:cc; bh=y7Y1GROIPsSLxY9do07YZACd9MWDSI2F+M+lT+f9eTo=; b=xWl6T19y3CG/hk/MwR9+6auPx8tnlMDd1ZQS0fbaMsF/8wDAlLadVfhjh5DYZtHv9v CLCDKmp4ybxmcv4W1I+p6TTyuOzRPC1tIQ7lIzsWD28z1zE2Iwi8mjnEdavDIVCpeRDo S+pOO31O1Ypofo6YM0vZYvpsfwqO8h4K+aOU46uDPt0bTScM3Ty6jGY+vcY7tYYZ+P87 Yta2DYR7m1GNuNNJhkJ/6hWSlSBYd0IsRiFHS2IobesqXjYyRwX2nhLQQoK4kM5JZYgS gS7Iep/VqJRloA+cTAEqnfeWSs4pQsP8xa07+81mI4BAx9TNn3tiPhPx0v4JEQQEn4iF dI8w== X-Gm-Message-State: AOAM532Dtsnz9GYSWUd9Vqpxp/uHYy2/pzGZRcUrbX9NefAZ/siZklX6 FZZcGFoir4PMDWggcqL6gVktT7DLqfiYdUwg7kZGs9IPCbE= X-Google-Smtp-Source: ABdhPJw/3jAU3O/Kq+1TUpmeh35Qr9Tn/HpTVk9i7/UR2pAUgLJf83vv627lUOfEnAPl1s5WNjyIbdnff/jjSlRos9o= X-Received: by 2002:aca:bd41:0:b0:2ec:ff42:814f with SMTP id n62-20020acabd41000000b002ecff42814fmr682476oif.63.1649722864112; Mon, 11 Apr 2022 17:21:04 -0700 (PDT) Received: from 753933720722 named unknown by gmailapi.google.com with HTTPREST; Mon, 11 Apr 2022 20:21:03 -0400 MIME-Version: 1.0 In-Reply-To: <1649722129-12542-1-git-send-email-quic_khsieh@quicinc.com> References: <1649722129-12542-1-git-send-email-quic_khsieh@quicinc.com> From: Stephen Boyd User-Agent: alot/0.10 Date: Mon, 11 Apr 2022 20:21:03 -0400 Message-ID: Subject: Re: [PATCH] drm/msm/dp: stop event kernel thread when DP unbind To: Kuogee Hsieh , agross@kernel.org, airlied@linux.ie, bjorn.andersson@linaro.org, daniel@ffwll.ch, dmitry.baryshkov@linaro.org, robdclark@gmail.com, sean@poorly.run, vkoul@kernel.org Cc: quic_abhinavk@quicinc.com, quic_aravindh@quicinc.com, quic_sbillaka@quicinc.com, freedreno@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quoting Kuogee Hsieh (2022-04-11 17:08:49) > Current DP driver implementation, event thread is kept running > after DP display is unbind. This patch fix this problem by disabling > DP irq and stop event thread to exit gracefully at dp_display_unbind(). > > Fixes: e91e3065a806 ("drm/msm/dp: Add DP compliance tests on Snapdragon Chipsets") > Signed-off-by: Kuogee Hsieh Should add a Reported-by tag from Dmitry here. > --- > drivers/gpu/drm/msm/dp/dp_display.c | 24 ++++++++++++++++++++++-- > 1 file changed, 22 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c > index 01453db..fa1ef8e 100644 > --- a/drivers/gpu/drm/msm/dp/dp_display.c > +++ b/drivers/gpu/drm/msm/dp/dp_display.c > @@ -273,6 +274,8 @@ static int dp_display_bind(struct device *dev, struct device *master, > return rc; > } > > +static void dp_hpd_event_stop(struct dp_display_private *dp_priv); Why can't the function be defined here? > + > static void dp_display_unbind(struct device *dev, struct device *master, > void *data) > { > @@ -280,6 +283,8 @@ static void dp_display_unbind(struct device *dev, struct device *master, > struct drm_device *drm = dev_get_drvdata(master); > struct msm_drm_private *priv = drm->dev_private; > > + disable_irq(dp->irq); > + dp_hpd_event_stop(dp); > dp_power_client_deinit(dp->power); > dp_aux_unregister(dp->aux); > priv->dp[dp->id] = NULL; > @@ -1054,7 +1059,7 @@ static int hpd_event_thread(void *data) > > dp_priv = (struct dp_display_private *)data; > > - while (1) { > + while (!kthread_should_stop()) { > if (timeout_mode) { > wait_event_timeout(dp_priv->event_q, > (dp_priv->event_pndx == dp_priv->event_gndx), > @@ -1137,7 +1142,22 @@ static void dp_hpd_event_setup(struct dp_display_private *dp_priv) > init_waitqueue_head(&dp_priv->event_q); > spin_lock_init(&dp_priv->event_lock); > > - kthread_run(hpd_event_thread, dp_priv, "dp_hpd_handler"); > + dp_priv->ev_tsk = kthread_run(hpd_event_thread, dp_priv, "dp_hpd_handler"); > + > + if (IS_ERR(dp_priv->ev_tsk)) > + DRM_ERROR("failed to create DP event thread\n"); Why can't we error out? Why can't this kthread be started in probe? > +} > + > +static void dp_hpd_event_stop(struct dp_display_private *dp_priv) > +{ > + if (IS_ERR(dp_priv->ev_tsk)) > + return; > + > + kthread_stop(dp_priv->ev_tsk); > + > + /* reset event q to empty */ > + dp_priv->event_gndx = 0; > + dp_priv->event_pndx = 0; > } >