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 0E15EC54FD0 for ; Fri, 24 Apr 2020 16:26:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D70C42071E for ; Fri, 24 Apr 2020 16:26:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kl.wtf header.i=@kl.wtf header.b="EM1KJp2T" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728435AbgDXQ02 (ORCPT ); Fri, 24 Apr 2020 12:26:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727863AbgDXQ01 (ORCPT ); Fri, 24 Apr 2020 12:26:27 -0400 X-Greylist: delayed 5686 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Fri, 24 Apr 2020 09:26:27 PDT Received: from out0.migadu.com (out0.migadu.com [IPv6:2001:41d0:2:267::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53EF0C09B046 for ; Fri, 24 Apr 2020 09:26:27 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kl.wtf; s=default; t=1587745584; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=8mdi2DQZnKTxhiyh5ltJlv4SJnThbSF3Vb3HnH3+DYU=; b=EM1KJp2Tn3uJ4k4JmB8agIjC8AO5zxy2CWr3tlHRh/VeOutwbf6EbybYXiabug4NXaOv77 BmPHjcchgF4NBvEy2nDq6iOpOQA/vS1egSLhZXHyZZ2Uy+ybaxnW5ShJJuD9anR0B///Dv 21x+3Ntcfp+3U0c6XL8z8yAnOuuNeJ0= From: Kenny Levinsen To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: daniel@ffwll.ch, airlied@linux.ie, tzimmermann@suse.de, mripard@kernel.org, maarten.lankhorst@linux.intel.com, linux-kernel@vger.kernel.org, Kenny Levinsen Subject: [PATCH v2] drm: make drm_file use keyed wakeups Date: Fri, 24 Apr 2020 18:26:15 +0200 Message-Id: <20200424162615.10461-1-kl@kl.wtf> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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