From patchwork Tue Apr 19 17:40:07 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Gordon X-Patchwork-Id: 8882331 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 91799BF29F for ; Tue, 19 Apr 2016 17:40:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id B893B202D1 for ; Tue, 19 Apr 2016 17:40:21 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id BF7A82026C for ; Tue, 19 Apr 2016 17:40:20 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id F267F6E7FD; Tue, 19 Apr 2016 17:40:19 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id 898F26E7FD for ; Tue, 19 Apr 2016 17:40:18 +0000 (UTC) Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga101.jf.intel.com with ESMTP; 19 Apr 2016 10:40:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,506,1455004800"; d="scan'208";a="948550889" Received: from dsgordon-linux2.isw.intel.com ([10.102.226.88]) by fmsmga001.fm.intel.com with ESMTP; 19 Apr 2016 10:40:16 -0700 From: Dave Gordon To: intel-gfx@lists.freedesktop.org Date: Tue, 19 Apr 2016 18:40:07 +0100 Message-Id: <1461087608-34346-1-git-send-email-david.s.gordon@intel.com> X-Mailer: git-send-email 1.9.1 Organization: Intel Corporation (UK) Ltd. - Co. Reg. #1134945 - Pipers Way, Swindon SN3 1RJ Subject: [Intel-gfx] [PATCH 1/2] drm/i915: refactor i915_gem_object_pin_map() X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Spam-Status: No, score=-5.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Alex Dai The recently-added i915_gem_object_pin_map() can be further optimised for "small" objects. To facilitate this, and simplify the error paths before adding the new code, this patch pulls out the "mapping" part of the operation (involving local allocations which must be undone before return) into its own subfunction. The next patch will then insert the new optimisation into the middle of the now-separated subfunction. This reorganisation will probably not affect the generated code, as the compiler will most likely inline it anyway, but it makes the logical structure a bit clearer and easier to modify. Signed-off-by: Dave Gordon Cc: Tvrtko Ursulin Cc: Chris Wilson --- drivers/gpu/drm/i915/i915_gem.c | 61 +++++++++++++++++++++++++++-------------- 1 file changed, 40 insertions(+), 21 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 6ce2c31..fc42be0 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2396,6 +2396,45 @@ static void i915_gem_object_free_mmap_offset(struct drm_i915_gem_object *obj) return 0; } +/* The 'mapping' part of i915_gem_object_pin_map() below */ +static void *i915_gem_object_map(const struct drm_i915_gem_object *obj) +{ + unsigned long n_pages = obj->base.size >> PAGE_SHIFT; + struct scatterlist *sg = obj->pages->sgl; + struct sg_page_iter sg_iter; + struct page **pages; + unsigned long i = 0; + void *addr = NULL; + + /* A single page can always be kmapped */ + if (n_pages == 1) + return kmap(sg_page(sg)); + + pages = drm_malloc_gfp(n_pages, sizeof(*pages), GFP_TEMPORARY); + if (pages == NULL) { + DRM_DEBUG_DRIVER("Failed to get space for pages\n"); + return NULL; + } + + for_each_sg_page(sg, &sg_iter, n_pages, 0) { + pages[i] = sg_page_iter_page(&sg_iter); + if (++i == n_pages) { + addr = vmap(pages, n_pages, 0, PAGE_KERNEL); + break; + } + } + + /* We should have got here via the 'break' above */ + WARN_ON(i != n_pages); + if (addr == NULL) + DRM_DEBUG_DRIVER("Failed to vmap pages\n"); + + drm_free_large(pages); + + return addr; +} + +/* get, pin, and map the pages of the object into kernel space */ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj) { int ret; @@ -2409,27 +2448,7 @@ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj) i915_gem_object_pin_pages(obj); if (obj->mapping == NULL) { - struct page **pages; - - pages = NULL; - if (obj->base.size == PAGE_SIZE) - obj->mapping = kmap(sg_page(obj->pages->sgl)); - else - pages = drm_malloc_gfp(obj->base.size >> PAGE_SHIFT, - sizeof(*pages), - GFP_TEMPORARY); - if (pages != NULL) { - struct sg_page_iter sg_iter; - int n; - - n = 0; - for_each_sg_page(obj->pages->sgl, &sg_iter, - obj->pages->nents, 0) - pages[n++] = sg_page_iter_page(&sg_iter); - - obj->mapping = vmap(pages, n, 0, PAGE_KERNEL); - drm_free_large(pages); - } + obj->mapping = i915_gem_object_map(obj); if (obj->mapping == NULL) { i915_gem_object_unpin_pages(obj); return ERR_PTR(-ENOMEM);