From patchwork Fri May 20 00:31:27 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Gordon X-Patchwork-Id: 9128483 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 87D6160467 for ; Fri, 20 May 2016 00:31:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 656EF2094F for ; Fri, 20 May 2016 00:31:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4679D212EF; Fri, 20 May 2016 00:31:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B53852094F for ; Fri, 20 May 2016 00:31:46 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3AA376EA1B; Fri, 20 May 2016 00:31:44 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTP id 0B8106EA1A for ; Fri, 20 May 2016 00:31:43 +0000 (UTC) Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga102.fm.intel.com with ESMTP; 19 May 2016 17:31:42 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,336,1459839600"; d="scan'208";a="107215283" Received: from dsgordon-linux2.isw.intel.com ([10.102.226.88]) by fmsmga004.fm.intel.com with ESMTP; 19 May 2016 17:31:41 -0700 From: Dave Gordon To: intel-gfx@lists.freedesktop.org Date: Fri, 20 May 2016 01:31:27 +0100 Message-Id: <1463704290-3491-1-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 v4 1/4] 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-Virus-Scanned: ClamAV using ClamSMTP 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. v2: Restructure loop-over-pages & error check [Chris Wilson] v3: Add page count to debug messages [Chris Wilson] Convert WARN_ON() to GEM_BUG_ON() v4: Drop the DEBUG messages [Tvrtko Ursulin] Signed-off-by: Dave Gordon Reviewed-by: Tvrtko Ursulin --- drivers/gpu/drm/i915/i915_gem.c | 54 +++++++++++++++++++++++++---------------- 1 file changed, 33 insertions(+), 21 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 6a31445..ac5fbf2 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2398,6 +2398,38 @@ 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 sg_table *sgt = obj->pages; + struct sg_page_iter sg_iter; + struct page **pages; + unsigned long i = 0; + void *addr; + + /* A single page can always be kmapped */ + if (n_pages == 1) + return kmap(sg_page(sgt->sgl)); + + pages = drm_malloc_gfp(n_pages, sizeof(*pages), GFP_TEMPORARY); + if (pages == NULL) + return NULL; + + for_each_sg_page(sgt->sgl, &sg_iter, sgt->nents, 0) + pages[i++] = sg_page_iter_page(&sg_iter); + + /* Check that we have the expected number of pages */ + GEM_BUG_ON(i != n_pages); + + addr = vmap(pages, n_pages, 0, PAGE_KERNEL); + + 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; @@ -2411,27 +2443,7 @@ 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);