From patchwork Wed Sep 4 11:56:42 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Zimmermann X-Patchwork-Id: 11129935 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 993DA14DE for ; Wed, 4 Sep 2019 11:56:59 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 81F8422CF5 for ; Wed, 4 Sep 2019 11:56:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 81F8422CF5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 123E7898ED; Wed, 4 Sep 2019 11:56:56 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by gabe.freedesktop.org (Postfix) with ESMTPS id 78ECC898C6 for ; Wed, 4 Sep 2019 11:56:53 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id C0BCFAD09; Wed, 4 Sep 2019 11:56:51 +0000 (UTC) From: Thomas Zimmermann To: daniel@ffwll.ch, noralf@tronnes.org, airlied@linux.ie, rong.a.chen@intel.com, feng.tang@intel.com, ying.huang@intel.com, sean@poorly.run, maxime.ripard@bootlin.com, maarten.lankhorst@linux.intel.com, dave@stgolabs.net Subject: [PATCH v2 1/3] drm/vram: Add kmap ref-counting to GEM VRAM objects Date: Wed, 4 Sep 2019 13:56:42 +0200 Message-Id: <20190904115644.7620-2-tzimmermann@suse.de> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190904115644.7620-1-tzimmermann@suse.de> References: <20190904115644.7620-1-tzimmermann@suse.de> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Thomas Zimmermann , dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The kmap and kunmap operations of GEM VRAM buffers can now be called in interleaving pairs. The first call to drm_gem_vram_kmap() maps the buffer's memory to kernel address space and the final call to drm_gem_vram_kunmap() unmaps the memory. Intermediate calls to these functions increment or decrement a reference counter. This change allows for keeping buffer memory mapped for longer and minimizes the amount of changes to TLB, page tables, etc. Signed-off-by: Thomas Zimmermann Cc: Davidlohr Bueso Reviewed-by: Gerd Hoffmann --- drivers/gpu/drm/drm_gem_vram_helper.c | 74 ++++++++++++++++++++------- include/drm/drm_gem_vram_helper.h | 19 +++++++ 2 files changed, 75 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c index fd751078bae1..6c7912092876 100644 --- a/drivers/gpu/drm/drm_gem_vram_helper.c +++ b/drivers/gpu/drm/drm_gem_vram_helper.c @@ -26,7 +26,11 @@ static void drm_gem_vram_cleanup(struct drm_gem_vram_object *gbo) * TTM buffer object in 'bo' has already been cleaned * up; only release the GEM object. */ + + WARN_ON(gbo->kmap_use_count); + drm_gem_object_release(&gbo->bo.base); + mutex_destroy(&gbo->kmap_lock); } static void drm_gem_vram_destroy(struct drm_gem_vram_object *gbo) @@ -100,6 +104,8 @@ static int drm_gem_vram_init(struct drm_device *dev, if (ret) goto err_drm_gem_object_release; + mutex_init(&gbo->kmap_lock); + return 0; err_drm_gem_object_release: @@ -283,6 +289,34 @@ int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo) } EXPORT_SYMBOL(drm_gem_vram_unpin); +static void *drm_gem_vram_kmap_locked(struct drm_gem_vram_object *gbo, + bool map, bool *is_iomem) +{ + int ret; + struct ttm_bo_kmap_obj *kmap = &gbo->kmap; + + if (gbo->kmap_use_count > 0) + goto out; + + if (kmap->virtual || !map) + goto out; + + ret = ttm_bo_kmap(&gbo->bo, 0, gbo->bo.num_pages, kmap); + if (ret) + return ERR_PTR(ret); + +out: + if (!kmap->virtual) { + if (is_iomem) + *is_iomem = false; + return NULL; /* not mapped; don't increment ref */ + } + ++gbo->kmap_use_count; + if (is_iomem) + return ttm_kmap_obj_virtual(kmap, is_iomem); + return kmap->virtual; +} + /** * drm_gem_vram_kmap() - Maps a GEM VRAM object into kernel address space * @gbo: the GEM VRAM object @@ -304,40 +338,44 @@ void *drm_gem_vram_kmap(struct drm_gem_vram_object *gbo, bool map, bool *is_iomem) { int ret; - struct ttm_bo_kmap_obj *kmap = &gbo->kmap; - - if (kmap->virtual || !map) - goto out; + void *virtual; - ret = ttm_bo_kmap(&gbo->bo, 0, gbo->bo.num_pages, kmap); + ret = mutex_lock_interruptible(&gbo->kmap_lock); if (ret) return ERR_PTR(ret); + virtual = drm_gem_vram_kmap_locked(gbo, map, is_iomem); + mutex_unlock(&gbo->kmap_lock); -out: - if (!is_iomem) - return kmap->virtual; - if (!kmap->virtual) { - *is_iomem = false; - return NULL; - } - return ttm_kmap_obj_virtual(kmap, is_iomem); + return virtual; } EXPORT_SYMBOL(drm_gem_vram_kmap); -/** - * drm_gem_vram_kunmap() - Unmaps a GEM VRAM object - * @gbo: the GEM VRAM object - */ -void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo) +static void drm_gem_vram_kunmap_locked(struct drm_gem_vram_object *gbo) { struct ttm_bo_kmap_obj *kmap = &gbo->kmap; + if (WARN_ON_ONCE(!gbo->kmap_use_count)) + return; + if (--gbo->kmap_use_count > 0) + return; + if (!kmap->virtual) return; ttm_bo_kunmap(kmap); kmap->virtual = NULL; } + +/** + * drm_gem_vram_kunmap() - Unmaps a GEM VRAM object + * @gbo: the GEM VRAM object + */ +void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo) +{ + mutex_lock(&gbo->kmap_lock); + drm_gem_vram_kunmap_locked(gbo); + mutex_unlock(&gbo->kmap_lock); +} EXPORT_SYMBOL(drm_gem_vram_kunmap); /** diff --git a/include/drm/drm_gem_vram_helper.h b/include/drm/drm_gem_vram_helper.h index ac217d768456..8c08bc87b788 100644 --- a/include/drm/drm_gem_vram_helper.h +++ b/include/drm/drm_gem_vram_helper.h @@ -34,11 +34,30 @@ struct vm_area_struct; * backed by VRAM. It can be used for simple framebuffer devices with * dedicated memory. The buffer object can be evicted to system memory if * video memory becomes scarce. + * + * GEM VRAM objects perform reference counting for pin and mapping + * operations. So a buffer object that has been pinned N times with + * drm_gem_vram_pin() must be unpinned N times with + * drm_gem_vram_unpin(). The same applies to pairs of + * drm_gem_vram_kmap() and drm_gem_vram_kunmap(). */ struct drm_gem_vram_object { struct ttm_buffer_object bo; struct ttm_bo_kmap_obj kmap; + /** + * @kmap_lock: Protects the kmap address and use count + */ + struct mutex kmap_lock; + + /** + * @kmap_use_count: + * + * Reference count on the virtual address. + * The address are un-mapped when the count reaches zero. + */ + unsigned int kmap_use_count; + /* Supported placements are %TTM_PL_VRAM and %TTM_PL_SYSTEM */ struct ttm_placement placement; struct ttm_place placements[2]; From patchwork Wed Sep 4 11:56:43 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Zimmermann X-Patchwork-Id: 11129937 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 73869112C for ; Wed, 4 Sep 2019 11:57:01 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5C12522CF5 for ; Wed, 4 Sep 2019 11:57:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5C12522CF5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 72DBB899B5; Wed, 4 Sep 2019 11:56:56 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7A3C5898C6 for ; Wed, 4 Sep 2019 11:56:54 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id BDB9BAD54; Wed, 4 Sep 2019 11:56:52 +0000 (UTC) From: Thomas Zimmermann To: daniel@ffwll.ch, noralf@tronnes.org, airlied@linux.ie, rong.a.chen@intel.com, feng.tang@intel.com, ying.huang@intel.com, sean@poorly.run, maxime.ripard@bootlin.com, maarten.lankhorst@linux.intel.com, dave@stgolabs.net Subject: [PATCH v2 2/3] drm/ast: Map fbdev framebuffer while it's being displayed Date: Wed, 4 Sep 2019 13:56:43 +0200 Message-Id: <20190904115644.7620-3-tzimmermann@suse.de> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190904115644.7620-1-tzimmermann@suse.de> References: <20190904115644.7620-1-tzimmermann@suse.de> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Oleksandr Andrushchenko , Sam Bobroff , Greg Kroah-Hartman , YueHaibing , dri-devel@lists.freedesktop.org, Alex Deucher , Huang Rui , Gerd Hoffmann , Thomas Zimmermann , Daniel Vetter , Dave Airlie , Thomas Gleixner , Sam Ravnborg , =?utf-8?q?Christian_K=C3=B6nig?= Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The generic fbdev emulation will map and unmap the framebuffer's memory if required. As consoles are most often updated while being on screen, we map the fbdev buffer while it's being displayed. This avoids frequent map/unmap operations in the fbdev code. The original fbdev code in ast used the same trick to improve performance. v2: * fix typo in comment Signed-off-by: Thomas Zimmermann Cc: Noralf Trønnes Cc: Dave Airlie Cc: Greg Kroah-Hartman Cc: Thomas Gleixner Cc: Sam Ravnborg Cc: Gerd Hoffmann Cc: Oleksandr Andrushchenko Cc: CK Hu Cc: Daniel Vetter Cc: Alex Deucher Cc: "Christian König" Cc: YueHaibing Cc: Sam Bobroff Cc: Huang Rui Cc: "Y.C. Chen" Cc: Rong Chen Cc: Feng Tang Cc: Huang Ying Cc: Davidlohr Bueso --- drivers/gpu/drm/ast/ast_mode.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c index d349c721501c..c10fff652228 100644 --- a/drivers/gpu/drm/ast/ast_mode.c +++ b/drivers/gpu/drm/ast/ast_mode.c @@ -529,13 +529,20 @@ static int ast_crtc_do_set_base(struct drm_crtc *crtc, struct drm_framebuffer *fb, int x, int y, int atomic) { + struct drm_fb_helper *fb_helper = crtc->dev->fb_helper; struct drm_gem_vram_object *gbo; int ret; s64 gpu_addr; + void *base; if (!atomic && fb) { gbo = drm_gem_vram_of_gem(fb->obj[0]); drm_gem_vram_unpin(gbo); + + // Unmap fbdev FB if it's not being displayed + // any longer. + if (fb == fb_helper->buffer->fb) + drm_gem_vram_kunmap(gbo); } gbo = drm_gem_vram_of_gem(crtc->primary->fb->obj[0]); @@ -552,6 +559,14 @@ static int ast_crtc_do_set_base(struct drm_crtc *crtc, ast_set_offset_reg(crtc); ast_set_start_address_crt1(crtc, (u32)gpu_addr); + // Map fbdev FB while it's being displayed. This avoids frequent + // mapping and unmapping within the fbdev code. + if (crtc->primary->fb == fb_helper->buffer->fb) { + base = drm_gem_vram_kmap(gbo, true, NULL); + if (IS_ERR(base)) + DRM_ERROR("failed to kmap fbcon\n"); + } + return 0; err_drm_gem_vram_unpin: @@ -605,10 +620,14 @@ static void ast_crtc_disable(struct drm_crtc *crtc) DRM_DEBUG_KMS("\n"); ast_crtc_dpms(crtc, DRM_MODE_DPMS_OFF); if (crtc->primary->fb) { + struct drm_fb_helper *fb_helper = crtc->dev->fb_helper; struct drm_framebuffer *fb = crtc->primary->fb; struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(fb->obj[0]); + // Unmap if it's the fbdev FB. + if (fb == fb_helper->buffer->fb) + drm_gem_vram_kunmap(gbo); drm_gem_vram_unpin(gbo); } crtc->primary->fb = NULL; From patchwork Wed Sep 4 11:56:44 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Zimmermann X-Patchwork-Id: 11129939 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2836C112C for ; Wed, 4 Sep 2019 11:57:03 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 10A1022CF5 for ; Wed, 4 Sep 2019 11:57:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 10A1022CF5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id F0C53898C6; Wed, 4 Sep 2019 11:56:56 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by gabe.freedesktop.org (Postfix) with ESMTPS id 93886898ED for ; Wed, 4 Sep 2019 11:56:54 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id F171FAE22; Wed, 4 Sep 2019 11:56:52 +0000 (UTC) From: Thomas Zimmermann To: daniel@ffwll.ch, noralf@tronnes.org, airlied@linux.ie, rong.a.chen@intel.com, feng.tang@intel.com, ying.huang@intel.com, sean@poorly.run, maxime.ripard@bootlin.com, maarten.lankhorst@linux.intel.com, dave@stgolabs.net Subject: [PATCH v2 3/3] drm/mgag200: Map fbdev framebuffer while it's being displayed Date: Wed, 4 Sep 2019 13:56:44 +0200 Message-Id: <20190904115644.7620-4-tzimmermann@suse.de> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190904115644.7620-1-tzimmermann@suse.de> References: <20190904115644.7620-1-tzimmermann@suse.de> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Bartlomiej Zolnierkiewicz , Greg Kroah-Hartman , dri-devel@lists.freedesktop.org, =?utf-8?b?TWljaGHFgiBNaXJvc8WCYXc=?= , Armijn Hemel , Huang Rui , Gerd Hoffmann , Thomas Zimmermann , Daniel Vetter , Alex Deucher , Dave Airlie , Thomas Gleixner , Sam Ravnborg , =?utf-8?q?Christian_K=C3=B6nig?= Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The generic fbdev emulation will map and unmap the framebuffer's memory if required. As consoles are most often updated while being on screen, we map the fbdev buffer while it's being displayed. This avoids frequent map/unmap operations in the fbdev code. The original fbdev code in mgag200 used the same trick to improve performance. v2: * fix typo in comment Signed-off-by: Thomas Zimmermann Fixes: 90f479ae51af ("drm/mgag200: Replace struct mga_fbdev with generic framebuffer emulation") Cc: Thomas Zimmermann Cc: Noralf Trønnes Cc: Dave Airlie Cc: Greg Kroah-Hartman Cc: Thomas Gleixner Cc: Gerd Hoffmann Cc: Alex Deucher Cc: "Christian König" Cc: Sam Ravnborg Cc: Daniel Vetter Cc: Huang Rui Cc: Bartlomiej Zolnierkiewicz Cc: "Michał Mirosław" Cc: Armijn Hemel Cc: Rong Chen Cc: Feng Tang Cc: Huang Ying Cc: Davidlohr Bueso --- drivers/gpu/drm/mgag200/mgag200_mode.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c index 5e778b5f1a10..7b95c59341f5 100644 --- a/drivers/gpu/drm/mgag200/mgag200_mode.c +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c @@ -860,13 +860,20 @@ static int mga_crtc_do_set_base(struct drm_crtc *crtc, struct drm_framebuffer *fb, int x, int y, int atomic) { + struct drm_fb_helper *fb_helper = crtc->dev->fb_helper; struct drm_gem_vram_object *gbo; int ret; s64 gpu_addr; + void *base; if (!atomic && fb) { gbo = drm_gem_vram_of_gem(fb->obj[0]); drm_gem_vram_unpin(gbo); + + // Unmap fbdev FB if it's not being displayed + // any longer. + if (fb == fb_helper->buffer->fb) + drm_gem_vram_kunmap(gbo); } gbo = drm_gem_vram_of_gem(crtc->primary->fb->obj[0]); @@ -882,6 +889,14 @@ static int mga_crtc_do_set_base(struct drm_crtc *crtc, mga_set_start_address(crtc, (u32)gpu_addr); + // Map fbdev FB while it's being displayed. This avoids frequent + // mapping and unmapping within the fbdev code. + if (crtc->primary->fb == fb_helper->buffer->fb) { + base = drm_gem_vram_kmap(gbo, true, NULL); + if (IS_ERR(base)) + DRM_ERROR("failed to kmap fbcon\n"); + } + return 0; err_drm_gem_vram_unpin: @@ -1403,9 +1418,14 @@ static void mga_crtc_disable(struct drm_crtc *crtc) DRM_DEBUG_KMS("\n"); mga_crtc_dpms(crtc, DRM_MODE_DPMS_OFF); if (crtc->primary->fb) { + struct drm_fb_helper *fb_helper = crtc->dev->fb_helper; struct drm_framebuffer *fb = crtc->primary->fb; struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(fb->obj[0]); + + // Unmap if it's the fbdev FB. + if (fb == fb_helper->buffer->fb) + drm_gem_vram_kunmap(gbo); drm_gem_vram_unpin(gbo); } crtc->primary->fb = NULL;