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=-6.8 required=3.0 tests=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 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 132CCC83001 for ; Tue, 28 Apr 2020 15:14:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2AF0206D8 for ; Tue, 28 Apr 2020 15:14:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="dt9JvUZu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728105AbgD1POQ (ORCPT ); Tue, 28 Apr 2020 11:14:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1727108AbgD1POP (ORCPT ); Tue, 28 Apr 2020 11:14:15 -0400 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EC7F1C03C1AB for ; Tue, 28 Apr 2020 08:14:13 -0700 (PDT) Received: by mail-wr1-x442.google.com with SMTP id d17so25096187wrg.11 for ; Tue, 28 Apr 2020 08:14:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:mail-followup-to:references :mime-version:content-disposition:in-reply-to; bh=gPj1O/jOW1qBAm9wItVCoQg+/JQBV9DNAyjrAa3CJ1s=; b=dt9JvUZu3Yez0wBMSlGnIr5B7uhLVVv3xwgu+ys50HNnfNjJK9xsLpXf2bo0UZ1oym ecWCqYvougpWP61bBgvZZAZn43EYIJgizSjuwvDRtGA34DKbLCNt331p+fseG19QtbW0 hLAenfbNLivynA523s4fRjSgUtRCZxbl616Nk= 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 :mail-followup-to:references:mime-version:content-disposition :in-reply-to; bh=gPj1O/jOW1qBAm9wItVCoQg+/JQBV9DNAyjrAa3CJ1s=; b=q/rAmU/2TRMV2QLgJFMglByzJrQevA7i9GPt79Drv4i3QUENyorBrPv3Nfdv17NL3t L3UubJcwnscsL0IUTj2TtGD/1sDyjgE1XB9adpd6nD3pwztyiF5bAlMRxUEPg0j/2f6k wOC9kctrkfu4wGZGoyyNIJJ+rUaZLC9rbExIxJQz7bJR9HUBtBZdG833znM5WRxVl3YB Z3JRhu5Qe6u/UD+EgLO6P9DRMvbxSfF4XHkssKsBDftOc78Tc3rrkStYjb0r4IsZMjR3 QD68ItOc5BOpAHg/+T8fPj8Vwt0XuVueUGwxwaJs4bOFyhklCngAGh5V4qk0CJcpVmbU qF5g== X-Gm-Message-State: AGi0PubXnhQjNs0J2IvkFYtb5YSiACwxVGGWT6S214Whmk84LeOA2SGJ 7yU/JYQzYq0TrHHUvfk3di/Ueg== X-Google-Smtp-Source: APiQypJnyMpVG5cmlGZH+PfTwmm3Qs/qc4+yVZMCFB9zhwRRInfXVOfPO1+oV4/KwUW3P+P7liGvaA== X-Received: by 2002:adf:e986:: with SMTP id h6mr33315188wrm.256.1588086852682; Tue, 28 Apr 2020 08:14:12 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id q8sm3611203wmg.22.2020.04.28.08.14.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Apr 2020 08:14:11 -0700 (PDT) Date: Tue, 28 Apr 2020 17:14:10 +0200 From: Daniel Vetter To: Kenny Levinsen Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, daniel@ffwll.ch, airlied@linux.ie, tzimmermann@suse.de, mripard@kernel.org, maarten.lankhorst@linux.intel.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] drm: make drm_file use keyed wakeups Message-ID: <20200428151410.GU3456981@phenom.ffwll.local> Mail-Followup-To: Kenny Levinsen , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, airlied@linux.ie, tzimmermann@suse.de, mripard@kernel.org, maarten.lankhorst@linux.intel.com, linux-kernel@vger.kernel.org References: <20200424162615.10461-1-kl@kl.wtf> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200424162615.10461-1-kl@kl.wtf> X-Operating-System: Linux phenom 5.3.0-3-amd64 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 24, 2020 at 06:26:15PM +0200, Kenny Levinsen wrote: > Some processes, such as systemd, are only polling for EPOLLERR|EPOLLHUP. > As drm_file uses unkeyed wakeups, such a poll can receive many spurious > wakeups from uninteresting events if, for example, the file description > is subscribed to vblank events. This is the case with systemd, as it > polls a file description from logind that is shared with the users' > compositor. > > Use keyed wakeups to allow the wakeup target to more efficiently discard > these uninteresting events. > > Signed-off-by: Kenny Levinsen Hm I applied v1 and I'm not spotting what's different here, and there's no changelog explaining what changed ... Please send a fixup if there's anything important missing. -Daniel > --- > drivers/gpu/drm/drm_file.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c > index c4c704e01961..ec25b3d979d9 100644 > --- a/drivers/gpu/drm/drm_file.c > +++ b/drivers/gpu/drm/drm_file.c > @@ -608,7 +608,8 @@ ssize_t drm_read(struct file *filp, char __user *buffer, > file_priv->event_space -= length; > list_add(&e->link, &file_priv->event_list); > spin_unlock_irq(&dev->event_lock); > - wake_up_interruptible(&file_priv->event_wait); > + wake_up_interruptible_poll(&file_priv->event_wait, > + EPOLLIN | EPOLLRDNORM); > break; > } > > @@ -804,7 +805,8 @@ void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e) > list_del(&e->pending_link); > list_add_tail(&e->link, > &e->file_priv->event_list); > - wake_up_interruptible(&e->file_priv->event_wait); > + wake_up_interruptible_poll(&e->file_priv->event_wait, > + EPOLLIN | EPOLLRDNORM); > } > EXPORT_SYMBOL(drm_send_event_locked); > > -- > 2.26.1 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch