From patchwork Tue Mar 5 10:34:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Hellstrom X-Patchwork-Id: 13582026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 775A9C54798 for ; Tue, 5 Mar 2024 10:35:22 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BBAD91129FB; Tue, 5 Mar 2024 10:35:17 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="I07UvRBr"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) by gabe.freedesktop.org (Postfix) with ESMTPS id EA83D10E453; Tue, 5 Mar 2024 10:35:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1709634915; x=1741170915; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=mzhSfBzhgLjoCHfR51r8IrsA+DMuI7GZzl6VbkV4pi8=; b=I07UvRBrOPWwQINXIb4ZDxgH57EtZxg3crFp9lfu0EVCCEjeLuWAWjgO jC0w2seJtxZiDxXBjHjPG20LYIfxyzQ527YHKmX0KQEH9blV4ge7DmUiS BpGilNVd6mI72tFCUcUembNrnXLrvTZrKV+4T84XSXA1PpAd5Z8Xk4i31 hZJbAhzXb94kRSA/SsWhneezh2OUaa7PKGWyRFQYv8jIBoa/e0Aac4veR ySCSnj4CmwH2kOjVYAs1l+7dHg2gg78pKYcrVZhYCq2+w1UXetTW+Xi4G GrLG1xK8vuehgpbkxj0wcBClUkLIy9WbiNvHpxL91QyJ0N7x9hgIMlsev g==; X-IronPort-AV: E=McAfee;i="6600,9927,11003"; a="4040331" X-IronPort-AV: E=Sophos;i="6.06,205,1705392000"; d="scan'208";a="4040331" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Mar 2024 02:35:15 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.06,205,1705392000"; d="scan'208";a="9184154" Received: from haslam-mobl1.ger.corp.intel.com (HELO fedora..) ([10.249.254.144]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Mar 2024 02:35:13 -0800 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Cc: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , =?utf-8?q?Christian_K=C3=B6nig?= , Somalapuram Amaranath , dri-devel@lists.freedesktop.org Subject: [PATCH v2 1/4] drm/ttm: Allow TTM LRU list nodes of different types Date: Tue, 5 Mar 2024 11:34:42 +0100 Message-ID: <20240305103445.75919-2-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240305103445.75919-1-thomas.hellstrom@linux.intel.com> References: <20240305103445.75919-1-thomas.hellstrom@linux.intel.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To be able to handle list unlocking while traversing the LRU list, we want the iterators not only to point to the next position of the list traversal, but to insert themselves as list nodes at that point to work around the fact that the next node might otherwise disappear from the list while the iterator is pointing to it. These list nodes need to be easily distinguishable from other list nodes so that others traversing the list can skip over them. So declare a struct ttm_lru_item, with a struct list_head member and a type enum. This will slightly increase the size of a struct ttm_resource. v2: - Update enum ttm_lru_item_type documentation. Cc: Christian König Cc: Somalapuram Amaranath Cc: Signed-off-by: Thomas Hellström --- drivers/gpu/drm/ttm/ttm_device.c | 13 ++++-- drivers/gpu/drm/ttm/ttm_resource.c | 70 ++++++++++++++++++++++-------- include/drm/ttm/ttm_resource.h | 51 +++++++++++++++++++++- 3 files changed, 110 insertions(+), 24 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_device.c b/drivers/gpu/drm/ttm/ttm_device.c index 76027960054f..f27406e851e5 100644 --- a/drivers/gpu/drm/ttm/ttm_device.c +++ b/drivers/gpu/drm/ttm/ttm_device.c @@ -270,17 +270,22 @@ EXPORT_SYMBOL(ttm_device_fini); static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev, struct list_head *list) { - struct ttm_resource *res; + struct ttm_lru_item *lru; spin_lock(&bdev->lru_lock); - while ((res = list_first_entry_or_null(list, typeof(*res), lru))) { - struct ttm_buffer_object *bo = res->bo; + while ((lru = list_first_entry_or_null(list, typeof(*lru), link))) { + struct ttm_buffer_object *bo; + + if (!ttm_lru_item_is_res(lru)) + continue; + + bo = ttm_lru_item_to_res(lru)->bo; /* Take ref against racing releases once lru_lock is unlocked */ if (!ttm_bo_get_unless_zero(bo)) continue; - list_del_init(&res->lru); + list_del_init(&bo->resource->lru.link); spin_unlock(&bdev->lru_lock); if (bo->ttm) diff --git a/drivers/gpu/drm/ttm/ttm_resource.c b/drivers/gpu/drm/ttm/ttm_resource.c index 65155f2013ca..ee1865f82cb4 100644 --- a/drivers/gpu/drm/ttm/ttm_resource.c +++ b/drivers/gpu/drm/ttm/ttm_resource.c @@ -69,8 +69,8 @@ void ttm_lru_bulk_move_tail(struct ttm_lru_bulk_move *bulk) dma_resv_assert_held(pos->last->bo->base.resv); man = ttm_manager_type(pos->first->bo->bdev, i); - list_bulk_move_tail(&man->lru[j], &pos->first->lru, - &pos->last->lru); + list_bulk_move_tail(&man->lru[j], &pos->first->lru.link, + &pos->last->lru.link); } } } @@ -83,14 +83,38 @@ ttm_lru_bulk_move_pos(struct ttm_lru_bulk_move *bulk, struct ttm_resource *res) return &bulk->pos[res->mem_type][res->bo->priority]; } +/* Return the previous resource on the list (skip over non-resource list items) */ +static struct ttm_resource *ttm_lru_prev_res(struct ttm_resource *cur) +{ + struct ttm_lru_item *lru = &cur->lru; + + do { + lru = list_prev_entry(lru, link); + } while (!ttm_lru_item_is_res(lru)); + + return ttm_lru_item_to_res(lru); +} + +/* Return the next resource on the list (skip over non-resource list items) */ +static struct ttm_resource *ttm_lru_next_res(struct ttm_resource *cur) +{ + struct ttm_lru_item *lru = &cur->lru; + + do { + lru = list_next_entry(lru, link); + } while (!ttm_lru_item_is_res(lru)); + + return ttm_lru_item_to_res(lru); +} + /* Move the resource to the tail of the bulk move range */ static void ttm_lru_bulk_move_pos_tail(struct ttm_lru_bulk_move_pos *pos, struct ttm_resource *res) { if (pos->last != res) { if (pos->first == res) - pos->first = list_next_entry(res, lru); - list_move(&res->lru, &pos->last->lru); + pos->first = ttm_lru_next_res(res); + list_move(&res->lru.link, &pos->last->lru.link); pos->last = res; } } @@ -120,11 +144,11 @@ static void ttm_lru_bulk_move_del(struct ttm_lru_bulk_move *bulk, pos->first = NULL; pos->last = NULL; } else if (pos->first == res) { - pos->first = list_next_entry(res, lru); + pos->first = ttm_lru_next_res(res); } else if (pos->last == res) { - pos->last = list_prev_entry(res, lru); + pos->last = ttm_lru_prev_res(res); } else { - list_move(&res->lru, &pos->last->lru); + list_move(&res->lru.link, &pos->last->lru.link); } } @@ -153,7 +177,7 @@ void ttm_resource_move_to_lru_tail(struct ttm_resource *res) lockdep_assert_held(&bo->bdev->lru_lock); if (bo->pin_count) { - list_move_tail(&res->lru, &bdev->pinned); + list_move_tail(&res->lru.link, &bdev->pinned); } else if (bo->bulk_move) { struct ttm_lru_bulk_move_pos *pos = @@ -164,7 +188,7 @@ void ttm_resource_move_to_lru_tail(struct ttm_resource *res) struct ttm_resource_manager *man; man = ttm_manager_type(bdev, res->mem_type); - list_move_tail(&res->lru, &man->lru[bo->priority]); + list_move_tail(&res->lru.link, &man->lru[bo->priority]); } } @@ -195,9 +219,9 @@ void ttm_resource_init(struct ttm_buffer_object *bo, man = ttm_manager_type(bo->bdev, place->mem_type); spin_lock(&bo->bdev->lru_lock); if (bo->pin_count) - list_add_tail(&res->lru, &bo->bdev->pinned); + list_add_tail(&res->lru.link, &bo->bdev->pinned); else - list_add_tail(&res->lru, &man->lru[bo->priority]); + list_add_tail(&res->lru.link, &man->lru[bo->priority]); man->usage += res->size; spin_unlock(&bo->bdev->lru_lock); } @@ -219,7 +243,7 @@ void ttm_resource_fini(struct ttm_resource_manager *man, struct ttm_device *bdev = man->bdev; spin_lock(&bdev->lru_lock); - list_del_init(&res->lru); + list_del_init(&res->lru.link); man->usage -= res->size; spin_unlock(&bdev->lru_lock); } @@ -470,14 +494,16 @@ struct ttm_resource * ttm_resource_manager_first(struct ttm_resource_manager *man, struct ttm_resource_cursor *cursor) { - struct ttm_resource *res; + struct ttm_lru_item *lru; lockdep_assert_held(&man->bdev->lru_lock); for (cursor->priority = 0; cursor->priority < TTM_MAX_BO_PRIORITY; ++cursor->priority) - list_for_each_entry(res, &man->lru[cursor->priority], lru) - return res; + list_for_each_entry(lru, &man->lru[cursor->priority], link) { + if (ttm_lru_item_is_res(lru)) + return ttm_lru_item_to_res(lru); + } return NULL; } @@ -496,15 +522,21 @@ ttm_resource_manager_next(struct ttm_resource_manager *man, struct ttm_resource_cursor *cursor, struct ttm_resource *res) { + struct ttm_lru_item *lru = &res->lru; + lockdep_assert_held(&man->bdev->lru_lock); - list_for_each_entry_continue(res, &man->lru[cursor->priority], lru) - return res; + list_for_each_entry_continue(lru, &man->lru[cursor->priority], link) { + if (ttm_lru_item_is_res(lru)) + return ttm_lru_item_to_res(lru); + } for (++cursor->priority; cursor->priority < TTM_MAX_BO_PRIORITY; ++cursor->priority) - list_for_each_entry(res, &man->lru[cursor->priority], lru) - return res; + list_for_each_entry(lru, &man->lru[cursor->priority], link) { + if (ttm_lru_item_is_res(lru)) + ttm_lru_item_to_res(lru); + } return NULL; } diff --git a/include/drm/ttm/ttm_resource.h b/include/drm/ttm/ttm_resource.h index 7561023db43d..cad8c5476198 100644 --- a/include/drm/ttm/ttm_resource.h +++ b/include/drm/ttm/ttm_resource.h @@ -49,6 +49,43 @@ struct io_mapping; struct sg_table; struct scatterlist; +/** + * enum ttm_lru_item_type - enumerate ttm_lru_item subclasses + */ +enum ttm_lru_item_type { + /** @TTM_LRU_RESOURCE: The resource subclass */ + TTM_LRU_RESOURCE, + /** @TTM_LRU_HITCH: The iterator hitch subclass */ + TTM_LRU_HITCH +}; + +/** + * struct ttm_lru_item - The TTM lru list node base class + * @link: The list link + * @type: The subclass type + */ +struct ttm_lru_item { + struct list_head link; + enum ttm_lru_item_type type; +}; + +/** + * ttm_lru_item_init() - initialize a struct ttm_lru_item + * @item: The item to initialize + * @type: The subclass type + */ +static inline void ttm_lru_item_init(struct ttm_lru_item *item, + enum ttm_lru_item_type type) +{ + item->type = type; + INIT_LIST_HEAD(&item->link); +} + +static inline bool ttm_lru_item_is_res(const struct ttm_lru_item *item) +{ + return item->type == TTM_LRU_RESOURCE; +} + struct ttm_resource_manager_func { /** * struct ttm_resource_manager_func member alloc @@ -217,9 +254,21 @@ struct ttm_resource { /** * @lru: Least recently used list, see &ttm_resource_manager.lru */ - struct list_head lru; + struct ttm_lru_item lru; }; +/** + * ttm_lru_item_to_res() - Downcast a struct ttm_lru_item to a struct ttm_resource + * @item: The struct ttm_lru_item to downcast + * + * Return: Pointer to the embedding struct ttm_resource + */ +static inline struct ttm_resource * +ttm_lru_item_to_res(struct ttm_lru_item *item) +{ + return container_of(item, struct ttm_resource, lru); +} + /** * struct ttm_resource_cursor *