From patchwork Mon Sep 15 22:09:16 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 389637 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 35EEE1400B2; Tue, 16 Sep 2014 08:14:51 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1XTeXo-0004u3-0y; Mon, 15 Sep 2014 22:14:48 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1XTeWF-000402-FT for kernel-team@lists.ubuntu.com; Mon, 15 Sep 2014 22:13:11 +0000 Received: from c-76-102-4-12.hsd1.ca.comcast.net ([76.102.4.12] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1XTeTh-0000AP-Ra; Mon, 15 Sep 2014 22:10:34 +0000 Received: from kamal by fourier with local (Exim 4.82) (envelope-from ) id 1XTeTg-0002hg-3L; Mon, 15 Sep 2014 15:10:32 -0700 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.13 146/187] drm/ttm: Choose a pool to shrink correctly in ttm_dma_pool_shrink_scan(). Date: Mon, 15 Sep 2014 15:09:16 -0700 Message-Id: <1410818997-9432-147-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1410818997-9432-1-git-send-email-kamal@canonical.com> References: <1410818997-9432-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Cc: Tetsuo Handa , Dave Airlie , Kamal Mostafa X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.13.11.7 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Tetsuo Handa commit 46c2df68f03a236b30808bba361f10900c88d95e upstream. We can use "unsigned int" instead of "atomic_t" by updating start_pool variable under _manager->lock. This patch will make it possible to avoid skipping when choosing a pool to shrink in round-robin style, after next patch changes mutex_lock(_manager->lock) to !mutex_trylock(_manager->lork). Signed-off-by: Tetsuo Handa Signed-off-by: Dave Airlie Signed-off-by: Kamal Mostafa --- drivers/gpu/drm/ttm/ttm_page_alloc_dma.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c index b751fff..d8e59f7 100644 --- a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c +++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c @@ -1004,9 +1004,9 @@ EXPORT_SYMBOL_GPL(ttm_dma_unpopulate); static unsigned long ttm_dma_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) { - static atomic_t start_pool = ATOMIC_INIT(0); + static unsigned start_pool; unsigned idx = 0; - unsigned pool_offset = atomic_add_return(1, &start_pool); + unsigned pool_offset; unsigned shrink_pages = sc->nr_to_scan; struct device_pools *p; unsigned long freed = 0; @@ -1017,7 +1017,7 @@ ttm_dma_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) mutex_lock(&_manager->lock); if (!_manager->npools) goto out; - pool_offset = pool_offset % _manager->npools; + pool_offset = ++start_pool % _manager->npools; list_for_each_entry(p, &_manager->pools, pools) { unsigned nr_free;