From patchwork Tue Sep 14 19:31:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Hellstrom X-Patchwork-Id: 12494479 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67FA5C433FE for ; Tue, 14 Sep 2021 19:31:39 +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 3598460F26 for ; Tue, 14 Sep 2021 19:31:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 3598460F26 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BE97089113; Tue, 14 Sep 2021 19:31:27 +0000 (UTC) Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id 21C5E6E5B6; Tue, 14 Sep 2021 19:31:26 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10107"; a="283110490" X-IronPort-AV: E=Sophos;i="5.85,292,1624345200"; d="scan'208";a="283110490" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Sep 2021 12:31:25 -0700 X-IronPort-AV: E=Sophos;i="5.85,292,1624345200"; d="scan'208";a="699629594" Received: from skofoed-mobl.ger.corp.intel.com (HELO thellstr-mobl1.intel.com) ([10.249.254.174]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Sep 2021 12:31:24 -0700 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: maarten.lankhorst@linux.intel.com, matthew.auld@intel.com, =?utf-8?q?Tho?= =?utf-8?q?mas_Hellstr=C3=B6m?= Date: Tue, 14 Sep 2021 21:31:08 +0200 Message-Id: <20210914193112.497379-3-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210914193112.497379-1-thomas.hellstrom@linux.intel.com> References: <20210914193112.497379-1-thomas.hellstrom@linux.intel.com> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH v3 2/6] drm/i915/gem: Implement a function to process all gem objects of a region X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" An upcoming common pattern is to traverse the region object list and perform certain actions on all objects in a region. It's a little tricky to get the list locking right, in particular since a gem object may change region unless it's pinned or the object lock is held. Define a function that does this for us and that takes an argument that defines the action to be performed on each object. v3: - Improve structure documentation a bit (Matthew Auld) Signed-off-by: Thomas Hellström Reviewed-by: Matthew Auld --- drivers/gpu/drm/i915/gem/i915_gem_region.c | 70 ++++++++++++++++++++++ drivers/gpu/drm/i915/gem/i915_gem_region.h | 37 ++++++++++++ 2 files changed, 107 insertions(+) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_region.c b/drivers/gpu/drm/i915/gem/i915_gem_region.c index 1f557b2178ed..a016ccec36f3 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_region.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_region.c @@ -80,3 +80,73 @@ i915_gem_object_create_region(struct intel_memory_region *mem, i915_gem_object_free(obj); return ERR_PTR(err); } + +/** + * i915_gem_process_region - Iterate over all objects of a region using ops + * to process and optionally skip objects + * @mr: The memory region + * @apply: ops and private data + * + * This function can be used to iterate over the regions object list, + * checking whether to skip objects, and, if not, lock the objects and + * process them using the supplied ops. Note that this function temporarily + * removes objects from the region list while iterating, so that if run + * concurrently with itself may not iterate over all objects. + * + * Return: 0 if successful, negative error code on failure. + */ +int i915_gem_process_region(struct intel_memory_region *mr, + struct i915_gem_apply_to_region *apply) +{ + const struct i915_gem_apply_to_region_ops *ops = apply->ops; + struct drm_i915_gem_object *obj; + struct list_head still_in_list; + int ret = 0; + + /* + * In the future, a non-NULL apply->ww could mean the caller is + * already in a locking transaction and provides its own context. + */ + GEM_WARN_ON(apply->ww); + + INIT_LIST_HEAD(&still_in_list); + mutex_lock(&mr->objects.lock); + for (;;) { + struct i915_gem_ww_ctx ww; + + obj = list_first_entry_or_null(&mr->objects.list, typeof(*obj), + mm.region_link); + if (!obj) + break; + + list_move_tail(&obj->mm.region_link, &still_in_list); + if (!kref_get_unless_zero(&obj->base.refcount)) + continue; + + /* + * Note: Someone else might be migrating the object at this + * point. The object's region is not stable until we lock + * the object. + */ + mutex_unlock(&mr->objects.lock); + apply->ww = &ww; + for_i915_gem_ww(&ww, ret, apply->interruptible) { + ret = i915_gem_object_lock(obj, apply->ww); + if (ret) + continue; + + if (obj->mm.region == mr) + ret = ops->process_obj(apply, obj); + /* Implicit object unlock */ + } + + i915_gem_object_put(obj); + mutex_lock(&mr->objects.lock); + if (ret) + break; + } + list_splice_tail(&still_in_list, &mr->objects.list); + mutex_unlock(&mr->objects.lock); + + return ret; +} diff --git a/drivers/gpu/drm/i915/gem/i915_gem_region.h b/drivers/gpu/drm/i915/gem/i915_gem_region.h index 1008e580a89a..fcaa12d657d4 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_region.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_region.h @@ -12,6 +12,41 @@ struct intel_memory_region; struct drm_i915_gem_object; struct sg_table; +struct i915_gem_apply_to_region; + +/** + * struct i915_gem_apply_to_region_ops - ops to use when iterating over all + * region objects. + */ +struct i915_gem_apply_to_region_ops { + /** + * process_obj - Process the current object + * @apply: Embed this for private data. + * @obj: The current object. + * + * Note that if this function is part of a ww transaction, and + * if returns -EDEADLK for one of the objects, it may be + * rerun for that same object in the same pass. + */ + int (*process_obj)(struct i915_gem_apply_to_region *apply, + struct drm_i915_gem_object *obj); +}; + +/** + * struct i915_gem_apply_to_region - Argument to the struct + * i915_gem_apply_to_region_ops functions. + * @ops: The ops for the operation. + * @ww: Locking context used for the transaction. + * @interruptible: Whether to perform object locking interruptible. + * + * This structure is intended to be embedded in a private struct if needed + */ +struct i915_gem_apply_to_region { + const struct i915_gem_apply_to_region_ops *ops; + struct i915_gem_ww_ctx *ww; + u32 interruptible:1; +}; + void i915_gem_object_init_memory_region(struct drm_i915_gem_object *obj, struct intel_memory_region *mem); void i915_gem_object_release_memory_region(struct drm_i915_gem_object *obj); @@ -22,4 +57,6 @@ i915_gem_object_create_region(struct intel_memory_region *mem, resource_size_t page_size, unsigned int flags); +int i915_gem_process_region(struct intel_memory_region *mr, + struct i915_gem_apply_to_region *apply); #endif