From nobody Mon Sep 15 18:06:09 2025 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 95858C46467 for ; Wed, 11 Jan 2023 15:53:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232251AbjAKPwu (ORCPT ); Wed, 11 Jan 2023 10:52:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239532AbjAKPwZ (ORCPT ); Wed, 11 Jan 2023 10:52:25 -0500 Received: from msg-2.mailo.com (msg-2.mailo.com [213.182.54.12]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C75EB3475B for ; Wed, 11 Jan 2023 07:52:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=mailo.com; s=mailo; t=1673452324; bh=QHeZldMKVWp9Cp9mxOeha2QFBOXYtsTVP8kjQEfSrZw=; h=X-EA-Auth:Date:From:To:Cc:Subject:Message-ID:References: MIME-Version:Content-Type:In-Reply-To; b=dhQ76Q5qWbdwieoX7S8a3HflKBaJR5R0TTGJXGnzA32tstm4XcijZEOvFS62J5qM5 VaQJIcf8JLwEM0aMQYeS8QIdcD7CJm5uN1jgkn/WSHLOy0PbnPvxXEKQzPhgzUzccW a0baxbbbXs7geGagVcVdV/18+jQTMvgzKA4nmfMc= Received: by b-1.in.mailobj.net [192.168.90.11] with ESMTP via ip-206.mailobj.net [213.182.55.206] Wed, 11 Jan 2023 16:52:03 +0100 (CET) X-EA-Auth: u5jvOLR5x9//Zkc8IMR5oNVJAAF0lJRlVIyLovRtl5gS15Vj30kxR2eXf+WDRR0PXE7lTP9chqyCJpfbE+S9CoqnkWNXnn/t Date: Wed, 11 Jan 2023 21:21:59 +0530 From: Deepak R Varma To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Cc: Saurabh Singh Sengar , Praveen Kumar Subject: [PATCH v3 2/2] drm/i915/fbc: Avoid full proxy f_ops for FBC debug attributes Message-ID: <5d26e924ec8dea21925c77fa79a2bf2a34cef705.1673451705.git.drv@mailo.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Using DEFINE_SIMPLE_ATTRIBUTE macro with the debugfs_create_file() function adds the overhead of introducing a proxy file operation functions to wrap the original read/write inside file removal protection functions. This adds significant overhead in terms of introducing and managing the proxy factory file operations structure and function wrapping at runtime. As a replacement, a combination of DEFINE_DEBUGFS_ATTRIBUTE macro paired with debugfs_create_file_unsafe() is suggested to be used instead. The DEFINE_DEBUGFS_ATTRIBUTE utilises debugfs_file_get() and debugfs_file_put() wrappers to protect the original read and write function calls for the debug attributes. There is no need for any runtime proxy file operations to be managed by the debugfs core. Following coccicheck make command helped identify this change: make coccicheck M=3Ddrivers/gpu/drm/i915/ MODE=3Dpatch COCCI=3D./scripts/co= ccinelle/api/debugfs/debugfs_simple_attr.cocci Signed-off-by: Deepak R Varma --- Changes in v3: - None Changes in v2: - Include coccicheck make command in the patch log message for clarity. Suggested by Rodrigo Vivi drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i91= 5/display/intel_fbc.c index 5e69d3c11d21..c508dcf415b4 100644 --- a/drivers/gpu/drm/i915/display/intel_fbc.c +++ b/drivers/gpu/drm/i915/display/intel_fbc.c @@ -1807,10 +1807,10 @@ static int intel_fbc_debugfs_false_color_set(void *= data, u64 val) return 0; } =20 -DEFINE_SIMPLE_ATTRIBUTE(intel_fbc_debugfs_false_color_fops, - intel_fbc_debugfs_false_color_get, - intel_fbc_debugfs_false_color_set, - "%llu\n"); +DEFINE_DEBUGFS_ATTRIBUTE(intel_fbc_debugfs_false_color_fops, + intel_fbc_debugfs_false_color_get, + intel_fbc_debugfs_false_color_set, + "%llu\n"); =20 static void intel_fbc_debugfs_add(struct intel_fbc *fbc, struct dentry *parent) @@ -1819,8 +1819,8 @@ static void intel_fbc_debugfs_add(struct intel_fbc *f= bc, fbc, &intel_fbc_debugfs_status_fops); =20 if (fbc->funcs->set_false_color) - debugfs_create_file("i915_fbc_false_color", 0644, parent, - fbc, &intel_fbc_debugfs_false_color_fops); + debugfs_create_file_unsafe("i915_fbc_false_color", 0644, parent, + fbc, &intel_fbc_debugfs_false_color_fops); } =20 void intel_fbc_crtc_debugfs_add(struct intel_crtc *crtc) --=20 2.34.1