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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, 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 512DFC432C3 for ; Wed, 20 Nov 2019 15:22:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2FC7220714 for ; Wed, 20 Nov 2019 15:22:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728619AbfKTPWj (ORCPT ); Wed, 20 Nov 2019 10:22:39 -0500 Received: from mga12.intel.com ([192.55.52.136]:64060 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727711AbfKTPWi (ORCPT ); Wed, 20 Nov 2019 10:22:38 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Nov 2019 07:22:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,222,1571727600"; d="scan'208";a="204848878" Received: from stinkbox.fi.intel.com (HELO stinkbox) ([10.237.72.174]) by fmsmga007.fm.intel.com with SMTP; 20 Nov 2019 07:22:35 -0800 Received: by stinkbox (sSMTP sendmail emulation); Wed, 20 Nov 2019 17:22:34 +0200 Date: Wed, 20 Nov 2019 17:22:34 +0200 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Benjamin Gaignard Cc: maarten.lankhorst@linux.intel.com, mripard@kernel.org, sean@poorly.run, airlied@linux.ie, daniel@ffwll.ch, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH] drm/rect: remove useless call to clamp_t Message-ID: <20191120152234.GG1208@intel.com> References: <20191119133435.22525-1-benjamin.gaignard@st.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20191119133435.22525-1-benjamin.gaignard@st.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 19, 2019 at 02:34:35PM +0100, Benjamin Gaignard wrote: > Clamping a value between INT_MIN and INT_MAX always return the value itself > and generate warnings when compiling with W=1. > > Signed-off-by: Benjamin Gaignard > --- > drivers/gpu/drm/drm_rect.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/drm_rect.c b/drivers/gpu/drm/drm_rect.c > index b8363aaa9032..681f1fd09357 100644 > --- a/drivers/gpu/drm/drm_rect.c > +++ b/drivers/gpu/drm/drm_rect.c > @@ -89,7 +89,7 @@ bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst, > u32 new_src_w = clip_scaled(drm_rect_width(src), > drm_rect_width(dst), diff); Hmm. I think we borked this a bit when introducing clip_scaled(). 'diff' can exceed dst width here so clip_scaled() should be able to return a negative value. Probably we should make this more consistent and do something like: diff = clip->x1 - dst->x1; if (diff > 0) { - u32 new_src_w = clip_scaled(drm_rect_width(src), - drm_rect_width(dst), diff); + int dst_w, new_src_w; - src->x1 = clamp_t(int64_t, src->x2 - new_src_w, INT_MIN, INT_MAX); - dst->x1 = clip->x1; + dst_w = drm_rect_width(dst); + diff = min(diff, dst_w); + new_src_w = clip_scaled(drm_rect_width(src), dst_w, diff); + + src->x1 = src->x2 - new_src_w; + dst->x1 += diff; } etc. > > - src->x1 = clamp_t(int64_t, src->x2 - new_src_w, INT_MIN, INT_MAX); > + src->x1 = src->x2 - new_src_w; > dst->x1 = clip->x1; > } > diff = clip->y1 - dst->y1; > @@ -97,7 +97,7 @@ bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst, > u32 new_src_h = clip_scaled(drm_rect_height(src), > drm_rect_height(dst), diff); > > - src->y1 = clamp_t(int64_t, src->y2 - new_src_h, INT_MIN, INT_MAX); > + src->y1 = src->y2 - new_src_h; > dst->y1 = clip->y1; > } > diff = dst->x2 - clip->x2; > @@ -105,7 +105,7 @@ bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst, > u32 new_src_w = clip_scaled(drm_rect_width(src), > drm_rect_width(dst), diff); > > - src->x2 = clamp_t(int64_t, src->x1 + new_src_w, INT_MIN, INT_MAX); > + src->x2 = src->x1 + new_src_w; > dst->x2 = clip->x2; > } > diff = dst->y2 - clip->y2; > @@ -113,7 +113,7 @@ bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst, > u32 new_src_h = clip_scaled(drm_rect_height(src), > drm_rect_height(dst), diff); > > - src->y2 = clamp_t(int64_t, src->y1 + new_src_h, INT_MIN, INT_MAX); > + src->y2 = src->y1 + new_src_h; > dst->y2 = clip->y2; > } > > -- > 2.15.0 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Ville Syrjälä Intel