From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756178AbZBJUxq (ORCPT ); Tue, 10 Feb 2009 15:53:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755277AbZBJUxi (ORCPT ); Tue, 10 Feb 2009 15:53:38 -0500 Received: from mail-fx0-f20.google.com ([209.85.220.20]:41829 "EHLO mail-fx0-f20.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755217AbZBJUxh (ORCPT ); Tue, 10 Feb 2009 15:53:37 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=ARhAVfIlF3YI+kFKAO6/XGAs7ZhuNUVmh+fH3jqz4em93e5q8+fS1s+jZ4D4iHl1fG ouEHmu2nMaSgeabNeXvSFQgoHsa+b9pdH9tCQIQU5YS5xhQd12qtHfssEP7LPVBXFkAr lb9xv8Z4YwwbfinaXrNSbQ9sCqBiPozx8agRk= Message-ID: <4991E812.80606@gmail.com> Date: Tue, 10 Feb 2009 21:48:18 +0100 From: Roel Kluin User-Agent: Thunderbird 2.0.0.18 (X11/20081105) MIME-Version: 1.0 To: =?ISO-8859-1?Q?Thomas_Hellstr=F6m?= CC: airlied@linux.ie, dri-devel@lists.sourceforge.net, lkml Subject: [PATCH v2] drm: count reaches -1, tested 0 References: <498EEB42.1050509@gmail.com> <4990ACA7.2080100@shipmail.org> In-Reply-To: <4990ACA7.2080100@shipmail.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thomas Hellström wrote: > This code is about to be abandoned, but if we're going to fix it, > instead of pushing the problem to then next while loop, what about > > while (count && condition) > count--; > > Can you redo the patch based on that? Very well reviewed, thanks. Like this? ------------------->8-----------------------8<------------------------ With a postfix decrement in the test count will reach -1 rather than 0, subsequent tests fail. Signed-off-by: Roel Kluin --- diff --git a/drivers/gpu/drm/via/via_dma.c b/drivers/gpu/drm/via/via_dma.c index 7a339db..029c22a 100644 --- a/drivers/gpu/drm/via/via_dma.c +++ b/drivers/gpu/drm/via/via_dma.c @@ -481,11 +481,12 @@ static int via_wait_idle(drm_via_private_t * dev_priv) { int count = 10000000; - while (!(VIA_READ(VIA_REG_STATUS) & VIA_VR_QUEUE_BUSY) && count--); + while (!(VIA_READ(VIA_REG_STATUS) & VIA_VR_QUEUE_BUSY) && --count) + ; - while (count-- && (VIA_READ(VIA_REG_STATUS) & - (VIA_CMD_RGTR_BUSY | VIA_2D_ENG_BUSY | - VIA_3D_ENG_BUSY))) ; + while (count && (VIA_READ(VIA_REG_STATUS) & (VIA_CMD_RGTR_BUSY | + VIA_2D_ENG_BUSY | VIA_3D_ENG_BUSY))) + count--; return count; } @@ -705,7 +706,7 @@ static int via_cmdbuf_size(struct drm_device *dev, void *data, struct drm_file * switch (d_siz->func) { case VIA_CMDBUF_SPACE: while (((tmp_size = via_cmdbuf_space(dev_priv)) < d_siz->size) - && count--) { + && --count) { if (!d_siz->wait) { break; } @@ -717,7 +718,7 @@ static int via_cmdbuf_size(struct drm_device *dev, void *data, struct drm_file * break; case VIA_CMDBUF_LAG: while (((tmp_size = via_cmdbuf_lag(dev_priv)) > d_siz->size) - && count--) { + && --count) { if (!d_siz->wait) { break; }