From patchwork Mon Sep 16 14:51:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Hellstr=C3=B6m?= X-Patchwork-Id: 13805550 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 CB9B7C3ABD1 for ; Mon, 16 Sep 2024 14:51:45 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5385B10E3A2; Mon, 16 Sep 2024 14:51:45 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="Xjz9LWfM"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) by gabe.freedesktop.org (Postfix) with ESMTPS id 973AB10E3A1; Mon, 16 Sep 2024 14:51:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1726498303; x=1758034303; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=waMGjUU4c819QX9rZ6M/04SpPkygIrFGAJzhtAj6dA4=; b=Xjz9LWfMUBp8E3YSTGX8ONmdNSaIOHg9jpiKNXcSvnr8thLrMQEUDvm+ MbhO+MG8MgCXMXfKq+U+4twq412afDS12gWftG5ylYUDg8FoXlsxB818r 9E3teGKzF5rZBE0uTnU5xdw0McTp7X3tmlhTeN3ozRmEaujf+UVrMd09g F0u+Ly9s3seVJVtpgBjTL86urBJwG3nn+KLMhXpXWAdSjTdcM8Omr7Bb+ eA3/CLd3YWrw3f2z7/uahMfGkxbOEIGudG5uoJR2j80LgVSi+Maw6V/Jb Fx6QMhXKlNf+G3QzEu+1yc5ZgPKQKONhHlv9bas0ORwayXl4t/gtazqMH g==; X-CSE-ConnectionGUID: GHa2mHquQbaIh+DF73oFUQ== X-CSE-MsgGUID: jsmJnfJSSzi9I90WGe12yw== X-IronPort-AV: E=McAfee;i="6700,10204,11197"; a="25259458" X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="25259458" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:43 -0700 X-CSE-ConnectionGUID: tUxQqo+QTJSmcY3xNNjXZg== X-CSE-MsgGUID: KIeums0gQR+dGSKiJsheJw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="68572942" Received: from dneilan-mobl1.ger.corp.intel.com (HELO fedora..) ([10.245.244.45]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:41 -0700 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org Cc: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , Matthew Brost , Somalapuram Amaranath , =?utf-8?q?Christian_?= =?utf-8?q?K=C3=B6nig?= , Paulo Zanoni , Simona Vetter , dri-devel@lists.freedesktop.org Subject: [PATCH v10 1/7] drm/ttm: Balance ttm_resource_cursor_init() and ttm_resource_cursor_fini() Date: Mon, 16 Sep 2024 16:51:06 +0200 Message-ID: <20240916145112.3336-2-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240916145112.3336-1-thomas.hellstrom@linux.intel.com> References: <20240916145112.3336-1-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" Make the interface more symmetric by providing and using a ttm_resource_cursor_init(). v10: - Fix a stray newline (Matthew Brost) - Update kerneldoc (Matthew Brost) Signed-off-by: Thomas Hellström Reviewed-by: Matthew Brost Reviewed-by: Christian König --- drivers/gpu/drm/ttm/ttm_bo.c | 3 ++- drivers/gpu/drm/ttm/ttm_bo_util.c | 3 ++- drivers/gpu/drm/ttm/ttm_resource.c | 35 ++++++++++++++++++++---------- include/drm/ttm/ttm_resource.h | 11 +++++----- 4 files changed, 34 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 320592435252..06a237d420dc 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -450,7 +450,8 @@ int ttm_bo_evict_first(struct ttm_device *bdev, struct ttm_resource_manager *man int ret = 0; spin_lock(&bdev->lru_lock); - res = ttm_resource_manager_first(man, &cursor); + ttm_resource_cursor_init(&cursor, man); + res = ttm_resource_manager_first(&cursor); ttm_resource_cursor_fini(&cursor); if (!res) { ret = -ENOENT; diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c index 3c07f4712d5c..454a51239614 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c @@ -865,7 +865,8 @@ s64 ttm_lru_walk_for_evict(struct ttm_lru_walk *walk, struct ttm_device *bdev, s64 lret; spin_lock(&bdev->lru_lock); - ttm_resource_manager_for_each_res(man, &cursor, res) { + ttm_resource_cursor_init(&cursor, man); + ttm_resource_manager_for_each_res(&cursor, res) { struct ttm_buffer_object *bo = res->bo; bool bo_needs_unlock = false; bool bo_locked = false; diff --git a/drivers/gpu/drm/ttm/ttm_resource.c b/drivers/gpu/drm/ttm/ttm_resource.c index 6d764ba88aab..2b69229f127c 100644 --- a/drivers/gpu/drm/ttm/ttm_resource.c +++ b/drivers/gpu/drm/ttm/ttm_resource.c @@ -80,6 +80,23 @@ static void ttm_bulk_move_drop_cursors(struct ttm_lru_bulk_move *bulk) ttm_resource_cursor_clear_bulk(cursor); } +/** + * ttm_resource_cursor_init() - Initialize a struct ttm_resource_cursor + * @cursor: The cursor to initialize. + * @man: The resource manager. + * + * Initialize the cursor before using it for iteration. + */ +void ttm_resource_cursor_init(struct ttm_resource_cursor *cursor, + struct ttm_resource_manager *man) +{ + cursor->priority = 0; + cursor->man = man; + ttm_lru_item_init(&cursor->hitch, TTM_LRU_HITCH); + INIT_LIST_HEAD(&cursor->bulk_link); + INIT_LIST_HEAD(&cursor->hitch.link); +} + /** * ttm_resource_cursor_fini() - Finalize the LRU list cursor usage * @cursor: The struct ttm_resource_cursor to finalize. @@ -577,7 +594,6 @@ ttm_resource_cursor_check_bulk(struct ttm_resource_cursor *cursor, /** * ttm_resource_manager_first() - Start iterating over the resources * of a resource manager - * @man: resource manager to iterate over * @cursor: cursor to record the position * * Initializes the cursor and starts iterating. When done iterating, @@ -586,17 +602,16 @@ ttm_resource_cursor_check_bulk(struct ttm_resource_cursor *cursor, * Return: The first resource from the resource manager. */ struct ttm_resource * -ttm_resource_manager_first(struct ttm_resource_manager *man, - struct ttm_resource_cursor *cursor) +ttm_resource_manager_first(struct ttm_resource_cursor *cursor) { - lockdep_assert_held(&man->bdev->lru_lock); + struct ttm_resource_manager *man = cursor->man; - cursor->priority = 0; - cursor->man = man; - ttm_lru_item_init(&cursor->hitch, TTM_LRU_HITCH); - INIT_LIST_HEAD(&cursor->bulk_link); - list_add(&cursor->hitch.link, &man->lru[cursor->priority]); + if (WARN_ON_ONCE(!man)) + return NULL; + + lockdep_assert_held(&man->bdev->lru_lock); + list_move(&cursor->hitch.link, &man->lru[cursor->priority]); return ttm_resource_manager_next(cursor); } @@ -632,8 +647,6 @@ ttm_resource_manager_next(struct ttm_resource_cursor *cursor) ttm_resource_cursor_clear_bulk(cursor); } - ttm_resource_cursor_fini(cursor); - return NULL; } diff --git a/include/drm/ttm/ttm_resource.h b/include/drm/ttm/ttm_resource.h index be034be56ba1..e1f3b95d73b6 100644 --- a/include/drm/ttm/ttm_resource.h +++ b/include/drm/ttm/ttm_resource.h @@ -325,6 +325,9 @@ struct ttm_resource_cursor { unsigned int priority; }; +void ttm_resource_cursor_init(struct ttm_resource_cursor *cursor, + struct ttm_resource_manager *man); + void ttm_resource_cursor_fini(struct ttm_resource_cursor *cursor); /** @@ -456,8 +459,7 @@ void ttm_resource_manager_debug(struct ttm_resource_manager *man, struct drm_printer *p); struct ttm_resource * -ttm_resource_manager_first(struct ttm_resource_manager *man, - struct ttm_resource_cursor *cursor); +ttm_resource_manager_first(struct ttm_resource_cursor *cursor); struct ttm_resource * ttm_resource_manager_next(struct ttm_resource_cursor *cursor); @@ -466,14 +468,13 @@ ttm_lru_first_res_or_null(struct list_head *head); /** * ttm_resource_manager_for_each_res - iterate over all resources - * @man: the resource manager * @cursor: struct ttm_resource_cursor for the current position * @res: the current resource * * Iterate over all the evictable resources in a resource manager. */ -#define ttm_resource_manager_for_each_res(man, cursor, res) \ - for (res = ttm_resource_manager_first(man, cursor); res; \ +#define ttm_resource_manager_for_each_res(cursor, res) \ + for (res = ttm_resource_manager_first(cursor); res; \ res = ttm_resource_manager_next(cursor)) struct ttm_kmap_iter * From patchwork Mon Sep 16 14:51:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Hellstr=C3=B6m?= X-Patchwork-Id: 13805551 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 E136CC3ABA2 for ; Mon, 16 Sep 2024 14:51:46 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6666010E3A3; Mon, 16 Sep 2024 14:51:45 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="mHr9H1Xp"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) by gabe.freedesktop.org (Postfix) with ESMTPS id C08B110E3A2; Mon, 16 Sep 2024 14:51:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1726498305; x=1758034305; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=scVNeAH/sVzt7SW+StGBLHdwG8ZMXGYTvDKcs+yK5bI=; b=mHr9H1Xp/8XA6cycS85w0Uiq39X3BBWCzzZj2ujOwGTQeuOCIJr0JGKU +3cEREANl/aXcwZDB5PRPFSvNka1/qWBdjSZfGt8YwOk9D3E2XLDo9eLS 8sM2E8dDQ40HmZI50O0XTULCK/Fwwe8iMJtETgMOZzuSfJWzIWsnk2FPC 6s1aBP1f4m+xKNo9wTDhv5YeXJELPmZZ3f2W3uO++1jlh+rZOp+sOilfv mR4EkAmOS0+2q7Vkc+38EjX7LGUT+AIBPpm2Z811KkOc+F7K3BjJo5bYs zj+AGiY6jdC/TkmvS3nk0GolHXZUL/X6LiTIsUVGat7K0gzfaIuUrVqj/ g==; X-CSE-ConnectionGUID: sYcw5IMbS+eUhY5vP8Zfxg== X-CSE-MsgGUID: 5eS66ZSXQRONJJ5d1dnJbQ== X-IronPort-AV: E=McAfee;i="6700,10204,11197"; a="25259463" X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="25259463" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:45 -0700 X-CSE-ConnectionGUID: gg77P/qtS/Sa8d8qIdcnHg== X-CSE-MsgGUID: vLojyfhSRzamw8FJk3C/pA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="68572951" Received: from dneilan-mobl1.ger.corp.intel.com (HELO fedora..) ([10.245.244.45]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:43 -0700 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org Cc: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , =?utf-8?q?Christian_K=C3=B6nig?= , Somalapuram Amaranath , Matthew Brost , dri-devel@lists.freedesktop.org, Paulo Zanoni , Simona Vetter Subject: [PATCH v10 2/7] drm/ttm: Add a virtual base class for graphics memory backup Date: Mon, 16 Sep 2024 16:51:07 +0200 Message-ID: <20240916145112.3336-3-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240916145112.3336-1-thomas.hellstrom@linux.intel.com> References: <20240916145112.3336-1-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" Initially intended for experimenting with different backup solutions (shmem vs direct swap cache insertion), abstract the backup destination using a virtual base class. Also provide a sample implementation for shmem. While when settling on a preferred backup solution, one could perhaps skip the abstraction, this functionality may actually come in handy for configurable dedicated graphics memory backup to fast nvme files or similar, whithout affecting swap-space. Could indeed be useful for VRAM backup on S4 and other cases. v5: - Fix a UAF. (kernel test robot, Dan Carptenter) v6: - Rename ttm_backup_shmem_copy_page() function argument (Matthew Brost) - Add some missing documentation v8: - Use folio_file_page to get to the page we want to writeback instead of using the first page of the folio. Cc: Christian König Cc: Somalapuram Amaranath Cc: Matthew Brost Cc: Signed-off-by: Thomas Hellström Reviewed-by: Matthew Brost #v7 --- drivers/gpu/drm/ttm/Makefile | 2 +- drivers/gpu/drm/ttm/ttm_backup_shmem.c | 139 +++++++++++++++++++++++++ include/drm/ttm/ttm_backup.h | 137 ++++++++++++++++++++++++ 3 files changed, 277 insertions(+), 1 deletion(-) create mode 100644 drivers/gpu/drm/ttm/ttm_backup_shmem.c create mode 100644 include/drm/ttm/ttm_backup.h diff --git a/drivers/gpu/drm/ttm/Makefile b/drivers/gpu/drm/ttm/Makefile index dad298127226..5e980dd90e41 100644 --- a/drivers/gpu/drm/ttm/Makefile +++ b/drivers/gpu/drm/ttm/Makefile @@ -4,7 +4,7 @@ ttm-y := ttm_tt.o ttm_bo.o ttm_bo_util.o ttm_bo_vm.o ttm_module.o \ ttm_execbuf_util.o ttm_range_manager.o ttm_resource.o ttm_pool.o \ - ttm_device.o ttm_sys_manager.o + ttm_device.o ttm_sys_manager.o ttm_backup_shmem.o ttm-$(CONFIG_AGP) += ttm_agp_backend.o obj-$(CONFIG_DRM_TTM) += ttm.o diff --git a/drivers/gpu/drm/ttm/ttm_backup_shmem.c b/drivers/gpu/drm/ttm/ttm_backup_shmem.c new file mode 100644 index 000000000000..cfe4140cc59d --- /dev/null +++ b/drivers/gpu/drm/ttm/ttm_backup_shmem.c @@ -0,0 +1,139 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2024 Intel Corporation + */ + +#include +#include + +/** + * struct ttm_backup_shmem - A shmem based ttm_backup subclass. + * @backup: The base struct ttm_backup + * @filp: The associated shmem object + */ +struct ttm_backup_shmem { + struct ttm_backup backup; + struct file *filp; +}; + +static struct ttm_backup_shmem *to_backup_shmem(struct ttm_backup *backup) +{ + return container_of(backup, struct ttm_backup_shmem, backup); +} + +static void ttm_backup_shmem_drop(struct ttm_backup *backup, unsigned long handle) +{ + handle -= 1; + shmem_truncate_range(file_inode(to_backup_shmem(backup)->filp), handle, + handle + 1); +} + +static int ttm_backup_shmem_copy_page(struct ttm_backup *backup, struct page *dst, + unsigned long handle, bool intr) +{ + struct file *filp = to_backup_shmem(backup)->filp; + struct address_space *mapping = filp->f_mapping; + struct folio *from_folio; + + handle -= 1; + from_folio = shmem_read_folio(mapping, handle); + if (IS_ERR(from_folio)) + return PTR_ERR(from_folio); + + /* Note: Use drm_memcpy_from_wc? */ + copy_highpage(dst, folio_file_page(from_folio, handle)); + folio_put(from_folio); + + return 0; +} + +static unsigned long +ttm_backup_shmem_backup_page(struct ttm_backup *backup, struct page *page, + bool writeback, pgoff_t i, gfp_t page_gfp, + gfp_t alloc_gfp) +{ + struct file *filp = to_backup_shmem(backup)->filp; + struct address_space *mapping = filp->f_mapping; + unsigned long handle = 0; + struct folio *to_folio; + int ret; + + to_folio = shmem_read_folio_gfp(mapping, i, alloc_gfp); + if (IS_ERR(to_folio)) + return handle; + + folio_mark_accessed(to_folio); + folio_lock(to_folio); + folio_mark_dirty(to_folio); + copy_highpage(folio_file_page(to_folio, i), page); + handle = i + 1; + + if (writeback && !folio_mapped(to_folio) && folio_clear_dirty_for_io(to_folio)) { + struct writeback_control wbc = { + .sync_mode = WB_SYNC_NONE, + .nr_to_write = SWAP_CLUSTER_MAX, + .range_start = 0, + .range_end = LLONG_MAX, + .for_reclaim = 1, + }; + folio_set_reclaim(to_folio); + ret = mapping->a_ops->writepage(folio_file_page(to_folio, i), &wbc); + if (!folio_test_writeback(to_folio)) + folio_clear_reclaim(to_folio); + /* If writepage succeeds, it unlocks the folio */ + if (ret) + folio_unlock(to_folio); + } else { + folio_unlock(to_folio); + } + + folio_put(to_folio); + + return handle; +} + +static void ttm_backup_shmem_fini(struct ttm_backup *backup) +{ + struct ttm_backup_shmem *sbackup = to_backup_shmem(backup); + + fput(sbackup->filp); + kfree(sbackup); +} + +static const struct ttm_backup_ops ttm_backup_shmem_ops = { + .drop = ttm_backup_shmem_drop, + .copy_backed_up_page = ttm_backup_shmem_copy_page, + .backup_page = ttm_backup_shmem_backup_page, + .fini = ttm_backup_shmem_fini, +}; + +/** + * ttm_backup_shmem_create() - Create a shmem-based struct backup. + * @size: The maximum size (in bytes) to back up. + * + * Create a backup utilizing shmem objects. + * + * Return: A pointer to a struct ttm_backup on success, + * an error pointer on error. + */ +struct ttm_backup *ttm_backup_shmem_create(loff_t size) +{ + struct ttm_backup_shmem *sbackup = + kzalloc(sizeof(*sbackup), GFP_KERNEL | __GFP_ACCOUNT); + struct file *filp; + + if (!sbackup) + return ERR_PTR(-ENOMEM); + + filp = shmem_file_setup("ttm shmem backup", size, 0); + if (IS_ERR(filp)) { + kfree(sbackup); + return ERR_CAST(filp); + } + + sbackup->filp = filp; + sbackup->backup.ops = &ttm_backup_shmem_ops; + + return &sbackup->backup; +} +EXPORT_SYMBOL_GPL(ttm_backup_shmem_create); diff --git a/include/drm/ttm/ttm_backup.h b/include/drm/ttm/ttm_backup.h new file mode 100644 index 000000000000..5f8c7d3069ef --- /dev/null +++ b/include/drm/ttm/ttm_backup.h @@ -0,0 +1,137 @@ +/* SPDX-License-Identifier: MIT */ +/* + * Copyright © 2024 Intel Corporation + */ + +#ifndef _TTM_BACKUP_H_ +#define _TTM_BACKUP_H_ + +#include +#include + +struct ttm_backup; + +/** + * ttm_backup_handle_to_page_ptr() - Convert handle to struct page pointer + * @handle: The handle to convert. + * + * Converts an opaque handle received from the + * struct ttm_backoup_ops::backup_page() function to an (invalid) + * struct page pointer suitable for a struct page array. + * + * Return: An (invalid) struct page pointer. + */ +static inline struct page * +ttm_backup_handle_to_page_ptr(unsigned long handle) +{ + return (struct page *)(handle << 1 | 1); +} + +/** + * ttm_backup_page_ptr_is_handle() - Whether a struct page pointer is a handle + * @page: The struct page pointer to check. + * + * Return: true if the struct page pointer is a handld returned from + * ttm_backup_handle_to_page_ptr(). False otherwise. + */ +static inline bool ttm_backup_page_ptr_is_handle(const struct page *page) +{ + return (unsigned long)page & 1; +} + +/** + * ttm_backup_page_ptr_to_handle() - Convert a struct page pointer to a handle + * @page: The struct page pointer to convert + * + * Return: The handle that was previously used in + * ttm_backup_handle_to_page_ptr() to obtain a struct page pointer, suitable + * for use as argument in the struct ttm_backup_ops drop() or + * copy_backed_up_page() functions. + */ +static inline unsigned long +ttm_backup_page_ptr_to_handle(const struct page *page) +{ + WARN_ON(!ttm_backup_page_ptr_is_handle(page)); + return (unsigned long)page >> 1; +} + +/** struct ttm_backup_ops - A struct ttm_backup backend operations */ +struct ttm_backup_ops { + /** + * drop - release memory associated with a handle + * @backup: The struct backup pointer used to obtain the handle + * @handle: The handle obtained from the @backup_page function. + */ + void (*drop)(struct ttm_backup *backup, unsigned long handle); + + /** + * copy_backed_up_page - Copy the contents of a previously backed + * up page + * @backup: The struct backup pointer used to back up the page. + * @dst: The struct page to copy into. + * @handle: The handle returned when the page was backed up. + * @intr: Try to perform waits interruptable or at least killable. + * + * Return: 0 on success, Negative error code on failure, notably + * -EINTR if @intr was set to true and a signal is pending. + */ + int (*copy_backed_up_page)(struct ttm_backup *backup, struct page *dst, + unsigned long handle, bool intr); + + /** + * backup_page - Backup a page + * @backup: The struct backup pointer to use. + * @page: The page to back up. + * @writeback: Whether to perform immediate writeback of the page. + * This may have performance implications. + * @i: A unique integer for each page and each struct backup. + * This is a hint allowing the backup backend to avoid managing + * its address space separately. + * @page_gfp: The gfp value used when the page was allocated. + * This is used for accounting purposes. + * @alloc_gfp: The gpf to be used when the backend needs to allocaete + * memory. + * + * Return: A handle on success. 0 on failure. + * (This is following the swp_entry_t convention). + * + * Note: This function could be extended to back up a folio and + * backends would then split the folio internally if needed. + * Drawback is that the caller would then have to keep track of + * the folio size- and usage. + */ + unsigned long (*backup_page)(struct ttm_backup *backup, struct page *page, + bool writeback, pgoff_t i, gfp_t page_gfp, + gfp_t alloc_gfp); + /** + * fini - Free the struct backup resources after last use. + * @backup: Pointer to the struct backup whose resources to free. + * + * After a call to @fini, it's illegal to use the @backup pointer. + */ + void (*fini)(struct ttm_backup *backup); +}; + +/** + * struct ttm_backup - Abstract a backup backend. + * @ops: The operations as described above. + * + * The struct ttm_backup is intended to be subclassed by the + * backend implementation. + */ +struct ttm_backup { + const struct ttm_backup_ops *ops; +}; + +/** + * ttm_backup_shmem_create() - Create a shmem-based struct backup. + * @size: The maximum size (in bytes) to back up. + * + * Create a backup utilizing shmem objects. + * + * Return: A pointer to a struct ttm_backup on success, + * an error pointer on error. + */ +struct ttm_backup *ttm_backup_shmem_create(loff_t size); + +#endif From patchwork Mon Sep 16 14:51:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Hellstr=C3=B6m?= X-Patchwork-Id: 13805553 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 D34E0C3ABB2 for ; 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([10.245.244.45]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:45 -0700 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org Cc: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , =?utf-8?q?Christian_K=C3=B6nig?= , Somalapuram Amaranath , Matthew Brost , dri-devel@lists.freedesktop.org, Paulo Zanoni , Simona Vetter Subject: [PATCH v10 3/7] drm/ttm/pool: Provide a helper to shrink pages Date: Mon, 16 Sep 2024 16:51:08 +0200 Message-ID: <20240916145112.3336-4-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240916145112.3336-1-thomas.hellstrom@linux.intel.com> References: <20240916145112.3336-1-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" Provide a helper to shrink ttm_tt page-vectors on a per-page basis. A ttm_backup backend could then in theory get away with allocating a single temporary page for each struct ttm_tt. This is accomplished by splitting larger pages before trying to back them up. In the future we could allow ttm_backup to handle backing up large pages as well, but currently there's no benefit in doing that, since the shmem backup backend would have to split those anyway to avoid allocating too much temporary memory, and if the backend instead inserts pages into the swap-cache, those are split on reclaim by the core. Due to potential backup- and recover errors, allow partially swapped out struct ttm_tt's, although mark them as swapped out stopping them from being swapped out a second time. More details in the ttm_pool.c DOC section. v2: - A couple of cleanups and error fixes in ttm_pool_back_up_tt. - s/back_up/backup/ - Add a writeback parameter to the exported interface. v8: - Use a struct for flags for readability (Matt Brost) - Address misc other review comments (Matt Brost) v9: - Update the kerneldoc for the ttm_tt::backup field. v10: - Rebase. Cc: Christian König Cc: Somalapuram Amaranath Cc: Matthew Brost Cc: Signed-off-by: Thomas Hellström --- drivers/gpu/drm/ttm/ttm_pool.c | 394 +++++++++++++++++++++++++++++++-- drivers/gpu/drm/ttm/ttm_tt.c | 37 ++++ include/drm/ttm/ttm_pool.h | 6 + include/drm/ttm/ttm_tt.h | 30 +++ 4 files changed, 454 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c index 8504dbe19c1a..0d224cd9f8eb 100644 --- a/drivers/gpu/drm/ttm/ttm_pool.c +++ b/drivers/gpu/drm/ttm/ttm_pool.c @@ -41,6 +41,7 @@ #include #endif +#include #include #include #include @@ -58,6 +59,32 @@ struct ttm_pool_dma { unsigned long vaddr; }; +/** + * struct ttm_pool_tt_restore - State representing restore from backup + * @alloced_pages: Total number of already allocated pages for the ttm_tt. + * @restored_pages: Number of (sub) pages restored from swap for this + * chunk of 1 << @order pages. + * @first_page: The ttm page ptr representing for @old_pages[0]. + * @caching_divide: Page pointer where subsequent pages are cached. + * @old_pages: Backup copy of page pointers that were replaced by the new + * page allocation. + * @pool: The pool used for page allocation while restoring. + * @order: The order of the last page allocated while restoring. + * + * Recovery from backup might fail when we've recovered less than the + * full ttm_tt. In order not to loose any data (yet), keep information + * around that allows us to restart a failed ttm backup recovery. + */ +struct ttm_pool_tt_restore { + pgoff_t alloced_pages; + pgoff_t restored_pages; + struct page **first_page; + struct page **caching_divide; + struct ttm_pool *pool; + unsigned int order; + struct page *old_pages[]; +}; + static unsigned long page_pool_size; MODULE_PARM_DESC(page_pool_size, "Number of pages in the WC/UC/DMA pool"); @@ -354,11 +381,102 @@ static unsigned int ttm_pool_page_order(struct ttm_pool *pool, struct page *p) return p->private; } +/* + * To be able to insert single pages into backup directly, + * we need to split multi-order page allocations and make them look + * like single-page allocations. + */ +static void ttm_pool_split_for_swap(struct ttm_pool *pool, struct page *p) +{ + unsigned int order = ttm_pool_page_order(pool, p); + pgoff_t nr; + + if (!order) + return; + + split_page(p, order); + nr = 1UL << order; + while (nr--) + (p++)->private = 0; +} + +/** + * DOC: Partial backup and restoration of a struct ttm_tt. + * + * Swapout using ttm_backup::ops::backup_page() and swapin using + * ttm_backup::ops::copy_backed_up_page() may fail. + * The former most likely due to lack of swap-space or memory, the latter due + * to lack of memory or because of signal interruption during waits. + * + * Backupfailure is easily handled by using a ttm_tt pages vector that holds + * both swap entries and page pointers. This has to be taken into account when + * restoring such a ttm_tt from backup, and when freeing it while backed up. + * When restoring, for simplicity, new pages are actually allocated from the + * pool and the contents of any old pages are copied in and then the old pages + * are released. + * + * For restoration failures, the struct ttm_pool_tt_restore holds sufficient state + * to be able to resume an interrupted restore, and that structure is freed once + * the restoration is complete. If the struct ttm_tt is destroyed while there + * is a valid struct ttm_pool_tt_restore attached, that is also properly taken + * care of. + */ + +static bool ttm_pool_restore_valid(const struct ttm_pool_tt_restore *restore) +{ + return restore && restore->restored_pages < (1 << restore->order); +} + +static int ttm_pool_restore_tt(struct ttm_pool_tt_restore *restore, + struct ttm_backup *backup, + struct ttm_operation_ctx *ctx) +{ + unsigned int i, nr = 1 << restore->order; + int ret = 0; + + if (!ttm_pool_restore_valid(restore)) + return 0; + + for (i = restore->restored_pages; i < nr; ++i) { + struct page *p = restore->old_pages[i]; + + if (ttm_backup_page_ptr_is_handle(p)) { + unsigned long handle = ttm_backup_page_ptr_to_handle(p); + + if (handle == 0) + continue; + + ret = backup->ops->copy_backed_up_page + (backup, restore->first_page[i], + handle, ctx->interruptible); + if (ret) + break; + + backup->ops->drop(backup, handle); + } else if (p) { + /* + * We could probably avoid splitting the old page + * using clever logic, but ATM we don't care. + */ + ttm_pool_split_for_swap(restore->pool, p); + copy_highpage(restore->first_page[i], p); + __free_pages(p, 0); + } + + restore->restored_pages++; + restore->old_pages[i] = NULL; + cond_resched(); + } + + return ret; +} + /* Called when we got a page, either from a pool or newly allocated */ static int ttm_pool_page_allocated(struct ttm_pool *pool, unsigned int order, struct page *p, dma_addr_t **dma_addr, unsigned long *num_pages, - struct page ***pages) + struct page ***pages, + struct ttm_pool_tt_restore *restore) { unsigned int i; int r; @@ -369,6 +487,16 @@ static int ttm_pool_page_allocated(struct ttm_pool *pool, unsigned int order, return r; } + if (restore) { + memcpy(restore->old_pages, *pages, + (1 << order) * sizeof(*restore->old_pages)); + memset(*pages, 0, (1 << order) * sizeof(**pages)); + restore->order = order; + restore->restored_pages = 0; + restore->first_page = *pages; + restore->alloced_pages += 1UL << order; + } + *num_pages -= 1 << order; for (i = 1 << order; i; --i, ++(*pages), ++p) **pages = p; @@ -394,22 +522,39 @@ static void ttm_pool_free_range(struct ttm_pool *pool, struct ttm_tt *tt, pgoff_t start_page, pgoff_t end_page) { struct page **pages = &tt->pages[start_page]; + struct ttm_backup *backup = tt->backup; unsigned int order; pgoff_t i, nr; for (i = start_page; i < end_page; i += nr, pages += nr) { struct ttm_pool_type *pt = NULL; + struct page *p = *pages; + + if (ttm_backup_page_ptr_is_handle(p)) { + unsigned long handle = ttm_backup_page_ptr_to_handle(p); + + nr = 1; + if (handle != 0) + backup->ops->drop(backup, handle); + continue; + } + + if (pool) { + order = ttm_pool_page_order(pool, p); + nr = (1UL << order); + if (tt->dma_address) + ttm_pool_unmap(pool, tt->dma_address[i], nr); - order = ttm_pool_page_order(pool, *pages); - nr = (1UL << order); - if (tt->dma_address) - ttm_pool_unmap(pool, tt->dma_address[i], nr); + pt = ttm_pool_select_type(pool, caching, order); + } else { + order = p->private; + nr = (1UL << order); + } - pt = ttm_pool_select_type(pool, caching, order); if (pt) - ttm_pool_type_give(pt, *pages); + ttm_pool_type_give(pt, p); else - ttm_pool_free_page(pool, caching, order, *pages); + ttm_pool_free_page(pool, caching, order, p); } } @@ -453,9 +598,36 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, else gfp_flags |= GFP_HIGHUSER; - for (order = min_t(unsigned int, MAX_PAGE_ORDER, __fls(num_pages)); - num_pages; - order = min_t(unsigned int, order, __fls(num_pages))) { + order = min_t(unsigned int, MAX_PAGE_ORDER, __fls(num_pages)); + + if (tt->page_flags & TTM_TT_FLAG_PRIV_BACKED_UP) { + if (!tt->restore) { + gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; + + if (ctx->gfp_retry_mayfail) + gfp |= __GFP_RETRY_MAYFAIL; + + tt->restore = + kvzalloc(struct_size(tt->restore, old_pages, + (size_t)1 << order), gfp); + if (!tt->restore) + return -ENOMEM; + } else if (ttm_pool_restore_valid(tt->restore)) { + struct ttm_pool_tt_restore *restore = tt->restore; + + num_pages -= restore->alloced_pages; + order = min_t(unsigned int, order, __fls(num_pages)); + pages += restore->alloced_pages; + r = ttm_pool_restore_tt(restore, tt->backup, ctx); + if (r) + return r; + caching = restore->caching_divide; + } + + tt->restore->pool = pool; + } + + for (; num_pages; order = min_t(unsigned int, order, __fls(num_pages))) { struct ttm_pool_type *pt; page_caching = tt->caching; @@ -472,11 +644,19 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, r = ttm_pool_page_allocated(pool, order, p, &dma_addr, &num_pages, - &pages); + &pages, + tt->restore); if (r) goto error_free_page; caching = pages; + if (ttm_pool_restore_valid(tt->restore)) { + r = ttm_pool_restore_tt(tt->restore, tt->backup, + ctx); + if (r) + goto error_free_all; + } + if (num_pages < (1 << order)) break; @@ -496,9 +676,17 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, caching = pages; } r = ttm_pool_page_allocated(pool, order, p, &dma_addr, - &num_pages, &pages); + &num_pages, &pages, + tt->restore); if (r) goto error_free_page; + + if (ttm_pool_restore_valid(tt->restore)) { + r = ttm_pool_restore_tt(tt->restore, tt->backup, ctx); + if (r) + goto error_free_all; + } + if (PageHighMem(p)) caching = pages; } @@ -517,12 +705,26 @@ int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt, if (r) goto error_free_all; + if (tt->restore) { + kvfree(tt->restore); + tt->restore = NULL; + } + + if (tt->page_flags & TTM_TT_FLAG_PRIV_BACKED_UP) + tt->page_flags &= ~(TTM_TT_FLAG_PRIV_BACKED_UP | + TTM_TT_FLAG_SWAPPED); + return 0; error_free_page: ttm_pool_free_page(pool, page_caching, order, p); error_free_all: + if (tt->page_flags & TTM_TT_FLAG_PRIV_BACKED_UP) { + tt->restore->caching_divide = caching; + return r; + } + num_pages = tt->num_pages - num_pages; caching_divide = caching - tt->pages; ttm_pool_free_range(pool, tt, tt->caching, 0, caching_divide); @@ -549,6 +751,172 @@ void ttm_pool_free(struct ttm_pool *pool, struct ttm_tt *tt) } EXPORT_SYMBOL(ttm_pool_free); +/** + * ttm_pool_release_backed_up() - Release content of a swapped-out struct ttm_tt + * @tt: The struct ttm_tt. + * + * Release handles with associated content or any remaining pages of + * a backed-up struct ttm_tt. + */ +void ttm_pool_release_backed_up(struct ttm_tt *tt) +{ + struct ttm_backup *backup = tt->backup; + struct ttm_pool_tt_restore *restore; + pgoff_t i, start_page = 0; + unsigned long handle; + + if (!(tt->page_flags & TTM_TT_FLAG_PRIV_BACKED_UP)) + return; + + restore = tt->restore; + + if (ttm_pool_restore_valid(restore)) { + pgoff_t nr = 1UL << restore->order; + + for (i = restore->restored_pages; i < nr; ++i) { + struct page *p = restore->old_pages[i]; + + if (ttm_backup_page_ptr_is_handle(p)) { + handle = ttm_backup_page_ptr_to_handle(p); + if (handle == 0) + continue; + + backup->ops->drop(backup, handle); + } else if (p) { + ttm_pool_split_for_swap(restore->pool, p); + __free_pages(p, 0); + } + } + } + + if (restore) { + pgoff_t mid = restore->caching_divide - tt->pages; + + start_page = restore->alloced_pages; + /* Pages that might be dma-mapped and non-cached */ + ttm_pool_free_range(restore->pool, tt, tt->caching, + 0, mid); + /* Pages that might be dma-mapped but cached */ + ttm_pool_free_range(restore->pool, tt, ttm_cached, + mid, restore->alloced_pages); + } + + /* Shrunken pages. Cached and not dma-mapped. */ + ttm_pool_free_range(NULL, tt, ttm_cached, start_page, tt->num_pages); + + if (restore) { + kvfree(restore); + tt->restore = NULL; + } + + tt->page_flags &= ~(TTM_TT_FLAG_PRIV_BACKED_UP | TTM_TT_FLAG_SWAPPED); +} + +/** + * ttm_pool_backup_tt() - Back up or purge a struct ttm_tt + * @pool: The pool used when allocating the struct ttm_tt. + * @ttm: The struct ttm_tt. + * @flags: Flags to govern the backup behaviour. + * + * Back up or purge a struct ttm_tt. If @purge is true, then + * all pages will be freed directly to the system rather than to the pool + * they were allocated from, making the function behave similarly to + * ttm_pool_free(). If @purge is false the pages will be backed up instead, + * exchanged for handles. + * A subsequent call to ttm_pool_alloc() will then read back the content and + * a subsequent call to ttm_pool_release_shrunken() will drop it. + * If backup of a page fails for whatever reason, @ttm will still be + * partially backed up, retaining those pages for which backup fails. + * + * Return: Number of pages actually backed up or freed, or negative + * error code on error. + */ +long ttm_pool_backup_tt(struct ttm_pool *pool, struct ttm_tt *ttm, + const struct ttm_backup_flags *flags) +{ + struct ttm_backup *backup = ttm->backup; + struct page *page; + unsigned long handle; + gfp_t alloc_gfp; + gfp_t gfp; + int ret = 0; + pgoff_t shrunken = 0; + pgoff_t i, num_pages; + + if ((!get_nr_swap_pages() && !flags->purge) || + pool->use_dma_alloc || + (ttm->page_flags & TTM_TT_FLAG_PRIV_BACKED_UP)) + return -EBUSY; + +#ifdef CONFIG_X86 + /* Anything returned to the system needs to be cached. */ + if (ttm->caching != ttm_cached) + set_pages_array_wb(ttm->pages, ttm->num_pages); +#endif + + if (ttm->dma_address || flags->purge) { + for (i = 0; i < ttm->num_pages; i += num_pages) { + unsigned int order; + + page = ttm->pages[i]; + if (unlikely(!page)) { + num_pages = 1; + continue; + } + + order = ttm_pool_page_order(pool, page); + num_pages = 1UL << order; + if (ttm->dma_address) + ttm_pool_unmap(pool, ttm->dma_address[i], + num_pages); + if (flags->purge) { + shrunken += num_pages; + page->private = 0; + __free_pages(page, order); + memset(ttm->pages + i, 0, + num_pages * sizeof(*ttm->pages)); + } + } + } + + if (flags->purge) + return shrunken; + + if (pool->use_dma32) + gfp = GFP_DMA32; + else + gfp = GFP_HIGHUSER; + + alloc_gfp = GFP_KERNEL | __GFP_HIGH | __GFP_NOWARN | __GFP_RETRY_MAYFAIL; + + for (i = 0; i < ttm->num_pages; ++i) { + page = ttm->pages[i]; + if (unlikely(!page)) + continue; + + ttm_pool_split_for_swap(pool, page); + + handle = backup->ops->backup_page(backup, page, flags->writeback, i, + gfp, alloc_gfp); + if (handle) { + ttm->pages[i] = ttm_backup_handle_to_page_ptr(handle); + put_page(page); + shrunken++; + } else { + /* We allow partially shrunken tts */ + ret = -ENOMEM; + break; + } + cond_resched(); + } + + if (shrunken) + ttm->page_flags |= (TTM_TT_FLAG_PRIV_BACKED_UP | + TTM_TT_FLAG_SWAPPED); + + return shrunken ? shrunken : ret; +} + /** * ttm_pool_init - Initialize a pool * diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c index 4b51b9023126..f520b8c93f03 100644 --- a/drivers/gpu/drm/ttm/ttm_tt.c +++ b/drivers/gpu/drm/ttm/ttm_tt.c @@ -40,6 +40,7 @@ #include #include #include +#include #include #include @@ -158,6 +159,8 @@ static void ttm_tt_init_fields(struct ttm_tt *ttm, ttm->swap_storage = NULL; ttm->sg = bo->sg; ttm->caching = caching; + ttm->restore = NULL; + ttm->backup = NULL; } int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo, @@ -182,6 +185,12 @@ void ttm_tt_fini(struct ttm_tt *ttm) fput(ttm->swap_storage); ttm->swap_storage = NULL; + ttm_pool_release_backed_up(ttm); + if (ttm->backup) { + ttm->backup->ops->fini(ttm->backup); + ttm->backup = NULL; + } + if (ttm->pages) kvfree(ttm->pages); else @@ -253,6 +262,34 @@ int ttm_tt_swapin(struct ttm_tt *ttm) } EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_swapin); +/** + * ttm_tt_backup() - Helper to back up a struct ttm_tt. + * @bdev: The TTM device. + * @tt: The struct ttm_tt. + * @flags: Flags that govern the backup behaviour. + * + * Update the page accounting and call ttm_pool_shrink_tt to free pages + * or back them up. + * + * Return: Number of pages freed or swapped out, or negative error code on + * error. + */ +long ttm_tt_backup(struct ttm_device *bdev, struct ttm_tt *tt, + const struct ttm_backup_flags flags) +{ + long ret; + + if (WARN_ON(IS_ERR_OR_NULL(tt->backup))) + return 0; + + ret = ttm_pool_backup_tt(&bdev->pool, tt, &flags); + + if (ret > 0) + tt->page_flags &= ~TTM_TT_FLAG_PRIV_POPULATED; + + return ret; +} + /** * ttm_tt_swapout - swap out tt object * diff --git a/include/drm/ttm/ttm_pool.h b/include/drm/ttm/ttm_pool.h index 160d954a261e..3112a4be835c 100644 --- a/include/drm/ttm/ttm_pool.h +++ b/include/drm/ttm/ttm_pool.h @@ -33,6 +33,7 @@ struct device; struct seq_file; +struct ttm_backup_flags; struct ttm_operation_ctx; struct ttm_pool; struct ttm_tt; @@ -89,6 +90,11 @@ void ttm_pool_fini(struct ttm_pool *pool); int ttm_pool_debugfs(struct ttm_pool *pool, struct seq_file *m); +void ttm_pool_release_backed_up(struct ttm_tt *tt); + +long ttm_pool_backup_tt(struct ttm_pool *pool, struct ttm_tt *ttm, + const struct ttm_backup_flags *flags); + int ttm_pool_mgr_init(unsigned long num_pages); void ttm_pool_mgr_fini(void); diff --git a/include/drm/ttm/ttm_tt.h b/include/drm/ttm/ttm_tt.h index 2b9d856ff388..c326165b8350 100644 --- a/include/drm/ttm/ttm_tt.h +++ b/include/drm/ttm/ttm_tt.h @@ -32,11 +32,13 @@ #include #include +struct ttm_backup; struct ttm_device; struct ttm_tt; struct ttm_resource; struct ttm_buffer_object; struct ttm_operation_ctx; +struct ttm_pool_tt_restore; /** * struct ttm_tt - This is a structure holding the pages, caching- and aperture @@ -88,6 +90,9 @@ struct ttm_tt { * TTM_TT_FLAG_PRIV_POPULATED: TTM internal only. DO NOT USE. This is * set by TTM after ttm_tt_populate() has successfully returned, and is * then unset when TTM calls ttm_tt_unpopulate(). + * + * TTM_TT_FLAG_PRIV_BACKED_UP: TTM internal only. This is set if the + * struct ttm_tt has been (possibly partially) backed up. */ #define TTM_TT_FLAG_SWAPPED BIT(0) #define TTM_TT_FLAG_ZERO_ALLOC BIT(1) @@ -96,6 +101,7 @@ struct ttm_tt { #define TTM_TT_FLAG_DECRYPTED BIT(4) #define TTM_TT_FLAG_PRIV_POPULATED BIT(5) +#define TTM_TT_FLAG_PRIV_BACKED_UP BIT(6) uint32_t page_flags; /** @num_pages: Number of pages in the page array. */ uint32_t num_pages; @@ -105,11 +111,20 @@ struct ttm_tt { dma_addr_t *dma_address; /** @swap_storage: Pointer to shmem struct file for swap storage. */ struct file *swap_storage; + /** + * @backup: Pointer to backup struct for backed up tts. + * Could be unified with @swap_storage. Meanwhile, the driver's + * ttm_tt_create() callback is responsible for assigning + * this field. + */ + struct ttm_backup *backup; /** * @caching: The current caching state of the pages, see enum * ttm_caching. */ enum ttm_caching caching; + /** @restore: Partial restoration from backup state. TTM private */ + struct ttm_pool_tt_restore *restore; }; /** @@ -230,6 +245,21 @@ void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages); struct ttm_kmap_iter *ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt, struct ttm_tt *tt); unsigned long ttm_tt_pages_limit(void); + +/** + * struct ttm_backup_flags - Flags to govern backup behaviour. + * @purge: Free pages without backing up. Bypass pools. + * @writeback: Attempt to copy contents directly to swap space, even + * if that means blocking on writes to external memory. + */ +struct ttm_backup_flags { + u32 purge : 1; + u32 writeback : 1; +}; + +long ttm_tt_backup(struct ttm_device *bdev, struct ttm_tt *tt, + const struct ttm_backup_flags flags); + #if IS_ENABLED(CONFIG_AGP) #include From patchwork Mon Sep 16 14:51:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Hellstr=C3=B6m?= X-Patchwork-Id: 13805552 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 029F4C3ABA2 for ; Mon, 16 Sep 2024 14:51:51 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6EB1010E3A8; Mon, 16 Sep 2024 14:51:50 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="QCC/IqV/"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) by gabe.freedesktop.org (Postfix) with ESMTPS id E3E7D10E3A6; Mon, 16 Sep 2024 14:51:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1726498309; x=1758034309; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=cE8ahukoEeOk2TS+49Md+fM2kF8TaNXqxFtJhcqnvqM=; b=QCC/IqV/P2Cm3EJ+TDtVTN1eztdLutXyXdo//9hpl0ZrVfsCJhA0BCdO Zt4/eAEh1etjl4UGys1TuPlxnKsCsWRvGQPOgsDjjhsuI22m8uuMplKcI QwLud7TFNzZosYnjuYZqgVwCST5ekIshHR/RHjUIb4OdBWhqeE33W0AzC aK6iWnI2tAGODYgde6RAb0prVtdWOvHAK8nBekkxNtOJdBUCUH60d671/ znRHqV+CuqsJRXmXOwVkq5asVbPZLkFfM3x1lYuvdUiCWN6viZUh0fRhF xa1pN9j0bZZ9PKtb7fXUMEvhrDkRkDeyh03BnORc1dbXAGhoIPU8ge6qg Q==; X-CSE-ConnectionGUID: veqvFQLISOWZZ/r0H8cVDw== X-CSE-MsgGUID: INDg2SqXTlq1RcKpXNoTxw== X-IronPort-AV: E=McAfee;i="6700,10204,11197"; a="25259474" X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="25259474" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:49 -0700 X-CSE-ConnectionGUID: SVuxJf3yRbW4Qlh1+CiNfw== X-CSE-MsgGUID: My9ih95iTuy/EnnkXOEB9g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="68572964" Received: from dneilan-mobl1.ger.corp.intel.com (HELO fedora..) ([10.245.244.45]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:47 -0700 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org Cc: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , =?utf-8?q?Christian_K=C3=B6nig?= , Somalapuram Amaranath , Matthew Brost , dri-devel@lists.freedesktop.org, Paulo Zanoni , Simona Vetter Subject: [PATCH v10 4/7] drm/ttm: Use fault-injection to test error paths Date: Mon, 16 Sep 2024 16:51:09 +0200 Message-ID: <20240916145112.3336-5-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240916145112.3336-1-thomas.hellstrom@linux.intel.com> References: <20240916145112.3336-1-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" Use fault-injection to test partial TTM swapout and interrupted swapin. Return -EINTR for swapin to test the callers ability to handle and restart the swapin, and on swapout perform a partial swapout to test that the swapin and release_shrunken functionality. v8: - Use the core fault-injection system. v9: - Fix compliation failure for !CONFIG_FAULT_INJECTION Cc: Christian König Cc: Somalapuram Amaranath Cc: Matthew Brost Cc: Signed-off-by: Thomas Hellström Reviewed-by: Matthew Brost #v7 --- drivers/gpu/drm/ttm/ttm_pool.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/ttm/ttm_pool.c b/drivers/gpu/drm/ttm/ttm_pool.c index 0d224cd9f8eb..b2718aef2edf 100644 --- a/drivers/gpu/drm/ttm/ttm_pool.c +++ b/drivers/gpu/drm/ttm/ttm_pool.c @@ -48,6 +48,13 @@ #include "ttm_module.h" +#ifdef CONFIG_FAULT_INJECTION +#include +static DECLARE_FAULT_ATTR(backup_fault_inject); +#else +#define should_fail(...) false +#endif + /** * struct ttm_pool_dma - Helper object for coherent DMA mappings * @@ -431,6 +438,7 @@ static int ttm_pool_restore_tt(struct ttm_pool_tt_restore *restore, struct ttm_backup *backup, struct ttm_operation_ctx *ctx) { + static unsigned long __maybe_unused swappedin; unsigned int i, nr = 1 << restore->order; int ret = 0; @@ -446,6 +454,12 @@ static int ttm_pool_restore_tt(struct ttm_pool_tt_restore *restore, if (handle == 0) continue; + if (IS_ENABLED(CONFIG_FAULT_INJECTION) && ctx->interruptible && + should_fail(&backup_fault_inject, 1)) { + ret = -EINTR; + break; + } + ret = backup->ops->copy_backed_up_page (backup, restore->first_page[i], handle, ctx->interruptible); @@ -889,7 +903,14 @@ long ttm_pool_backup_tt(struct ttm_pool *pool, struct ttm_tt *ttm, alloc_gfp = GFP_KERNEL | __GFP_HIGH | __GFP_NOWARN | __GFP_RETRY_MAYFAIL; - for (i = 0; i < ttm->num_pages; ++i) { + num_pages = ttm->num_pages; + + /* Pretend doing fault injection by shrinking only half of the pages. */ + + if (IS_ENABLED(CONFIG_FAULT_INJECTION) && should_fail(&backup_fault_inject, 1)) + num_pages = DIV_ROUND_UP(num_pages, 2); + + for (i = 0; i < num_pages; ++i) { page = ttm->pages[i]; if (unlikely(!page)) continue; @@ -1178,6 +1199,10 @@ int ttm_pool_mgr_init(unsigned long num_pages) &ttm_pool_debugfs_globals_fops); debugfs_create_file("page_pool_shrink", 0400, ttm_debugfs_root, NULL, &ttm_pool_debugfs_shrink_fops); +#ifdef CONFIG_FAULT_INJECTION + fault_create_debugfs_attr("backup_fault_inject", ttm_debugfs_root, + &backup_fault_inject); +#endif #endif mm_shrinker = shrinker_alloc(0, "drm-ttm_pool"); From patchwork Mon Sep 16 14:51:10 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Hellstr=C3=B6m?= X-Patchwork-Id: 13805554 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 79A27C3ABD1 for ; Mon, 16 Sep 2024 14:51:56 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id DF8DA10E3A5; Mon, 16 Sep 2024 14:51:55 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="W7003kxB"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) by gabe.freedesktop.org (Postfix) with ESMTPS id E89D510E3A9; Mon, 16 Sep 2024 14:51:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1726498311; x=1758034311; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ym8mdaAkB+dXBYTVbmhaTVZprwHT/NtSCwXnzODRSRs=; b=W7003kxByCmM7pb/pga7b8IBwOTMW76BAfw8iGHd28cg22lmBms/Y/B1 N3rpi99Qp6RIVqWshxDmj9kWaqqXU1wHON2CKkMUGMc24BrhLBREYF1VK pvws8tR5fCuhDhJOupx8hCgHXFbu7JNhYTRvo6bW9Fu5w4A0j5CYm1LH1 /wy5pPo/C/PsmJ6cJGUmbOy0sq6N+kemULh+ZOwAcSOKl6p+WYELmdmyM viiiqX4zZADM7wFzQLdWni17j5Lih07xdT09i1llOlreWEn81s05rVnC/ jTs9KD4nqvB5afli2c2gH5rB0Qz5p0m3lJaGf+x/xUEQWS0RzgzLkmcAV A==; X-CSE-ConnectionGUID: 2dnyUnbLRPSJQv3YD7724w== X-CSE-MsgGUID: yGDYmkMhQf+JGwSAYqeX1g== X-IronPort-AV: E=McAfee;i="6700,10204,11197"; a="25259479" X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="25259479" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:51 -0700 X-CSE-ConnectionGUID: 9E/aQTwVR1uLgNwIoMfKhA== X-CSE-MsgGUID: YnTxCizkQRmodAUFqNMuVQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="68572970" Received: from dneilan-mobl1.ger.corp.intel.com (HELO fedora..) ([10.245.244.45]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:49 -0700 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org Cc: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , Matthew Brost , Somalapuram Amaranath , =?utf-8?q?Christian_?= =?utf-8?q?K=C3=B6nig?= , Paulo Zanoni , Simona Vetter , dri-devel@lists.freedesktop.org Subject: [PATCH v10 5/7] drm/ttm: Add a shrinker helper and a macro to perform LRU iteration Date: Mon, 16 Sep 2024 16:51:10 +0200 Message-ID: <20240916145112.3336-6-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240916145112.3336-1-thomas.hellstrom@linux.intel.com> References: <20240916145112.3336-1-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" Following the design direction communicated here: https://lore.kernel.org/linux-mm/b7491378-defd-4f1c-31e2-29e4c77e2d67@amd.com/T/#ma918844aa8a6efe8768fdcda0c6590d5c93850c9 Export the LRU walker for driver shrinker use and add a bo shrinker helper for initial use by the xe driver. v8: - Split out from another patch. - Use a struct for bool arguments to increase readability (Matt Brost). - Unmap user-space cpu-mappings before shrinking pages. - Explain non-fatal error codes (Matt Brost) v10: - Instead of using the existing helper, Wrap the interface inside out and provide a loop to de-midlayer things the LRU iteration (Christian König). - Removing the R-B by Matt Brost since the patch was significantly changed. Signed-off-by: Thomas Hellström --- drivers/gpu/drm/ttm/ttm_bo_util.c | 204 +++++++++++++++++++++++++++++- include/drm/ttm/ttm_bo.h | 88 +++++++++++++ 2 files changed, 288 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c index 454a51239614..b619cd7b3fab 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c @@ -769,12 +769,10 @@ int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo) return ret; } -static bool ttm_lru_walk_trylock(struct ttm_lru_walk *walk, +static bool ttm_lru_walk_trylock(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, bool *needs_unlock) { - struct ttm_operation_ctx *ctx = walk->ctx; - *needs_unlock = false; if (dma_resv_trylock(bo->base.resv)) { @@ -877,7 +875,7 @@ s64 ttm_lru_walk_for_evict(struct ttm_lru_walk *walk, struct ttm_device *bdev, * since if we do it the other way around, and the trylock fails, * we need to drop the lru lock to put the bo. */ - if (ttm_lru_walk_trylock(walk, bo, &bo_needs_unlock)) + if (ttm_lru_walk_trylock(walk->ctx, bo, &bo_needs_unlock)) bo_locked = true; else if (!walk->ticket || walk->ctx->no_wait_gpu || walk->trylock_only) @@ -920,3 +918,201 @@ s64 ttm_lru_walk_for_evict(struct ttm_lru_walk *walk, struct ttm_device *bdev, return progress; } +EXPORT_SYMBOL(ttm_lru_walk_for_evict); + +/** + * ttm_bo_try_shrink - LRU walk helper to shrink a ttm buffer object. + * @ctx: The struct ttm_operation_ctx used for the shrinking operation. + * @bo: The buffer object. + * @flags: Flags governing the shrinking behaviour. + * + * The function uses the ttm_tt_back_up functionality to back up or + * purge a struct ttm_tt. If the bo is not in system, it's first + * moved there. + * + * Return: The number of pages shrunken or purged, or + * negative error code on failure. + */ +long ttm_bo_try_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, + const struct ttm_bo_shrink_flags flags) +{ + static const struct ttm_place sys_placement_flags = { + .fpfn = 0, + .lpfn = 0, + .mem_type = TTM_PL_SYSTEM, + .flags = 0, + }; + static struct ttm_placement sys_placement = { + .num_placement = 1, + .placement = &sys_placement_flags, + }; + struct ttm_tt *tt = bo->ttm; + long lret; + + dma_resv_assert_held(bo->base.resv); + + if (!tt || !ttm_tt_is_populated(tt)) + return 0; + + if (flags.allow_move && bo->resource->mem_type != TTM_PL_SYSTEM) { + int ret = ttm_bo_validate(bo, &sys_placement, ctx); + + /* Consider -ENOMEM and -ENOSPC non-fatal. */ + if (ret) { + if (ret == -ENOMEM || ret == -ENOSPC) + ret = -EBUSY; + return ret; + } + } + + ttm_bo_unmap_virtual(bo); + lret = ttm_bo_wait_ctx(bo, ctx); + if (lret < 0) { + if (lret == -ERESTARTSYS) + return lret; + return 0; + } + + lret = ttm_tt_backup(bo->bdev, tt, (struct ttm_backup_flags) + {.purge = flags.purge, + .writeback = flags.writeback}); + + if (lret < 0 && lret != -EINTR) + return 0; + + return lret; +} +EXPORT_SYMBOL(ttm_bo_try_shrink); + +static void ttm_bo_lru_cursor_cleanup_bo(struct ttm_bo_lru_cursor *curs) +{ + struct ttm_buffer_object *bo = curs->bo; + + if (bo) { + if (curs->needs_unlock) + dma_resv_unlock(bo->base.resv); + ttm_bo_put(bo); + curs->bo = NULL; + } +} + +/** + * ttm_bo_lru_cursor_fini() - Stop using a struct ttm_bo_lru_cursor + * and clean up any iteration it was used for. + * @curs: The cursor. + */ +void ttm_bo_lru_cursor_fini(struct ttm_bo_lru_cursor *curs) +{ + spinlock_t *lru_lock = &curs->res_curs.man->bdev->lru_lock; + + ttm_bo_lru_cursor_cleanup_bo(curs); + spin_lock(lru_lock); + ttm_resource_cursor_fini(&curs->res_curs); + spin_unlock(lru_lock); +} +EXPORT_SYMBOL(ttm_bo_lru_cursor_fini); + +/** + * ttm_bo_lru_cursor_init() - Initialize a struct ttm_bo_lru_cursor + * @curs: The ttm_bo_lru_cursor to initialize. + * @man: The ttm resource_manager whose LRU lists to iterate over. + * @ctx: The ttm_operation_ctx to govern the locking. + * + * Initialize a struct ttm_bo_lru_cursor. Currently only trylocking + * or prelocked buffer objects are available as detailed by + * @ctx::resv and @ctx::allow_res_evict. Ticketlocking is not + * supported. + * + * Return: Pointer to @curs. The function does not fail. + */ +struct ttm_bo_lru_cursor * +ttm_bo_lru_cursor_init(struct ttm_bo_lru_cursor *curs, + struct ttm_resource_manager *man, + struct ttm_operation_ctx *ctx) +{ + memset(curs, 0, sizeof(*curs)); + ttm_resource_cursor_init(&curs->res_curs, man); + curs->ctx = ctx; + + return curs; +} +EXPORT_SYMBOL(ttm_bo_lru_cursor_init); + +static struct ttm_buffer_object * +ttm_bo_from_res_reserved(struct ttm_resource *res, struct ttm_bo_lru_cursor *curs) +{ + struct ttm_buffer_object *bo = res->bo; + + if (!ttm_lru_walk_trylock(curs->ctx, bo, &curs->needs_unlock)) + return NULL; + + if (!ttm_bo_get_unless_zero(bo)) { + if (curs->needs_unlock) + dma_resv_unlock(bo->base.resv); + return NULL; + } + + curs->bo = bo; + return bo; +} + +/** + * ttm_bo_lru_cursor_next() - Continue iterating a manager's LRU lists + * to find and lock buffer object. + * @curs: The cursor initialized using ttm_bo_lru_cursor_init() and + * ttm_bo_lru_cursor_first(). + * + * Return: A pointer to a locked and reference-counted buffer object, + * or NULL if none could be found and looping should be terminated. + */ +struct ttm_buffer_object *ttm_bo_lru_cursor_next(struct ttm_bo_lru_cursor *curs) +{ + spinlock_t *lru_lock = &curs->res_curs.man->bdev->lru_lock; + struct ttm_resource *res = NULL; + struct ttm_buffer_object *bo; + + ttm_bo_lru_cursor_cleanup_bo(curs); + + spin_lock(lru_lock); + for (;;) { + res = ttm_resource_manager_next(&curs->res_curs); + if (!res) + break; + + bo = ttm_bo_from_res_reserved(res, curs); + if (bo) + break; + } + + spin_unlock(lru_lock); + return res ? bo : NULL; +} +EXPORT_SYMBOL(ttm_bo_lru_cursor_next); + +/** + * ttm_bo_lru_cursor_first() - Start iterating a manager's LRU lists + * to find and lock buffer object. + * @curs: The cursor initialized using ttm_bo_lru_cursor_init(). + * + * Return: A pointer to a locked and reference-counted buffer object, + * or NULL if none could be found and looping should be terminated. + */ +struct ttm_buffer_object *ttm_bo_lru_cursor_first(struct ttm_bo_lru_cursor *curs) +{ + spinlock_t *lru_lock = &curs->res_curs.man->bdev->lru_lock; + struct ttm_buffer_object *bo; + struct ttm_resource *res; + + spin_lock(lru_lock); + res = ttm_resource_manager_first(&curs->res_curs); + if (!res) { + spin_unlock(lru_lock); + return NULL; + } + + bo = ttm_bo_from_res_reserved(res, curs); + spin_unlock(lru_lock); + + return bo ? bo : ttm_bo_lru_cursor_next(curs); +} +EXPORT_SYMBOL(ttm_bo_lru_cursor_first); diff --git a/include/drm/ttm/ttm_bo.h b/include/drm/ttm/ttm_bo.h index 7b56d1ca36d7..48749c097f93 100644 --- a/include/drm/ttm/ttm_bo.h +++ b/include/drm/ttm/ttm_bo.h @@ -225,6 +225,23 @@ struct ttm_lru_walk { s64 ttm_lru_walk_for_evict(struct ttm_lru_walk *walk, struct ttm_device *bdev, struct ttm_resource_manager *man, s64 target); +/** + * struct ttm_bo_shrink_flags - flags to govern the bo shrinking behaviour + * @purge: Purge the content rather than backing it up. + * @writeback: Attempt to immediately write content to swap space. + * @allow_move: Allow moving to system before shrinking. This is typically + * not desired for zombie- or ghost objects (with zombie object meaning + * objects with a zero gem object refcount) + */ +struct ttm_bo_shrink_flags { + u32 purge : 1; + u32 writeback : 1; + u32 allow_move : 1; +}; + +long ttm_bo_try_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, + const struct ttm_bo_shrink_flags flags); + /** * ttm_bo_get - reference a struct ttm_buffer_object * @@ -463,4 +480,75 @@ pgprot_t ttm_io_prot(struct ttm_buffer_object *bo, struct ttm_resource *res, pgprot_t tmp); void ttm_bo_tt_destroy(struct ttm_buffer_object *bo); +/* Driver LRU walk helpers initially targeted for shrinking. */ + +/** + * struct ttm_bo_lru_cursor - Iterator cursor for TTM LRU list looping + */ +struct ttm_bo_lru_cursor { + /** @res_curs: Embedded struct ttm_resource_cursor. */ + struct ttm_resource_cursor res_curs; + /** + * @ctx: The struct ttm_operation_ctx used while looping. + * governs the locking mode. + */ + struct ttm_operation_ctx *ctx; + /** + * @bo: Buffer object pointer if a buffer object is refcounted, + * NULL otherwise. + */ + struct ttm_buffer_object *bo; + /** + * @needs_unlock: Valid iff @bo != NULL. The bo resv needs + * unlock before the next iteration or after loop exit. + */ + bool needs_unlock; +}; + +void ttm_bo_lru_cursor_fini(struct ttm_bo_lru_cursor *curs); + +struct ttm_bo_lru_cursor * +ttm_bo_lru_cursor_init(struct ttm_bo_lru_cursor *curs, + struct ttm_resource_manager *man, + struct ttm_operation_ctx *ctx); + +struct ttm_buffer_object *ttm_bo_lru_cursor_first(struct ttm_bo_lru_cursor *curs); + +struct ttm_buffer_object *ttm_bo_lru_cursor_next(struct ttm_bo_lru_cursor *curs); + +/* + * Defines needed to use autocleanup (linux/cleanup.h) with struct ttm_bo_lru_cursor. + */ +DEFINE_CLASS(ttm_bo_lru_cursor, struct ttm_bo_lru_cursor *, + if (_T) {ttm_bo_lru_cursor_fini(_T); }, + ttm_bo_lru_cursor_init(curs, man, ctx), + struct ttm_bo_lru_cursor *curs, struct ttm_resource_manager *man, + struct ttm_operation_ctx *ctx); +static inline void * +class_ttm_bo_lru_cursor_lock_ptr(class_ttm_bo_lru_cursor_t *_T) +{ return *_T; } + +/** + * ttm_bo_lru_for_each_reserved_guarded() - Iterate over buffer objects owning + * resources on LRU lists. + * @_cursor: struct ttm_bo_lru_cursor to use for the iteration. + * @_man: The resource manager whose LRU lists to iterate over. + * @_ctx: The struct ttm_operation_context to govern the @_bo locking. + * @_bo: The struct ttm_buffer_object pointer pointing to the buffer object + * for the current iteration. + * + * Iterate over all resources of @_man and for each resource, attempt to + * reference and lock (using the locking mode detailed in @_ctx) the buffer + * object it points to. If successful, assign @_bo to the address of the + * buffer object and update @_cursor. The iteration is guarded in the + * sense that @_cursor will be initialized before looping start and cleaned + * up at looping termination, even if terminated prematurely by, for + * example a return or break statement. Exiting the loop will also unlock + * (if needed) and unreference @_bo. + */ +#define ttm_bo_lru_for_each_reserved_guarded(_cursor, _man, _ctx, _bo) \ + scoped_guard(ttm_bo_lru_cursor, _cursor, _man, _ctx) \ + for ((_bo) = ttm_bo_lru_cursor_first(_cursor); (_bo); \ + (_bo) = ttm_bo_lru_cursor_next(_cursor)) + #endif From patchwork Mon Sep 16 14:51:11 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Hellstr=C3=B6m?= X-Patchwork-Id: 13805555 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 0BAF0C3ABB2 for ; Mon, 16 Sep 2024 14:51:56 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8A57510E3A1; Mon, 16 Sep 2024 14:51:55 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="aTvd8SAy"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0A95410E3AA; Mon, 16 Sep 2024 14:51:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1726498313; x=1758034313; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=6fQ11UXkTY/DnjUYk0LiGCAJcExdXOLNpNfZPsN4q2M=; b=aTvd8SAyoTar1Ikq3cpzbcnZyLMPtzBiSLtMvkpCIs/4CL2t9gk3vSHj c3DEInxt3yR75E0dW2diZowq6nWjuCEyNCnzaFKruX2/NlJAG2wUGR63q gZPNm6+vuiDJZEUGZmx9kVt5392LEJbNrS6z1rUZZvTcE4zHOarDmTLuD zC+am90LEWkX99GQYPwPpEfqWinwnB73aWAtOlizDjxC4sU9o1srp0lzo 6W+/5NGyZ8UuCRGFKvZuTL+pz2H0X7i6PjTW0qI10UFLg5WHIjeYHaiAP uTKhQAtTkybt57GCdMD0kmEf8dZVkB7Mawmd/JACsom5CK7GwhWCoaP0x w==; X-CSE-ConnectionGUID: 5jRw5tOLRsy/H/CI39Vtng== X-CSE-MsgGUID: BoTx5tw5TRulzKJVV9ZLvQ== X-IronPort-AV: E=McAfee;i="6700,10204,11197"; a="25259485" X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="25259485" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:53 -0700 X-CSE-ConnectionGUID: 6QystbvUSPyQCmcpj9zVmA== X-CSE-MsgGUID: Dh58KyXjT12n/yi1BE66JQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,233,1719903600"; d="scan'208";a="68572975" Received: from dneilan-mobl1.ger.corp.intel.com (HELO fedora..) ([10.245.244.45]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:51 -0700 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org Cc: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , =?utf-8?q?Christian_K=C3=B6nig?= , Somalapuram Amaranath , Matthew Brost , dri-devel@lists.freedesktop.org, Paulo Zanoni , Simona Vetter Subject: [PATCH v10 6/7] drm/xe: Add a shrinker for xe bos Date: Mon, 16 Sep 2024 16:51:11 +0200 Message-ID: <20240916145112.3336-7-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240916145112.3336-1-thomas.hellstrom@linux.intel.com> References: <20240916145112.3336-1-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" Rather than relying on the TTM watermark accounting add a shrinker for xe_bos in TT or system memory. Leverage the newly added TTM per-page shrinking and shmem backup support. Although xe doesn't fully support WONTNEED (purgeable) bos yet, introduce and add shrinker support for purgeable ttm_tts. v2: - Cleanups bugfixes and a KUNIT shrinker test. - Add writeback support, and activate if kswapd. v3: - Move the try_shrink() helper to core TTM. - Minor cleanups. v4: - Add runtime pm for the shrinker. Shrinking may require an active device for CCS metadata copying. v5: - Separately purge ghost- and zombie objects in the shrinker. - Fix a format specifier - type inconsistency. (Kernel test robot). v7: - s/long/s64/ (Christian König) - s/sofar/progress/ (Matt Brost) v8: - Rebase on Xe KUNIT update. - Add content verifying to the shrinker kunit test. - Split out TTM changes to a separate patch. - Get rid of multiple bool arguments for clarity (Matt Brost) - Avoid an error pointer dereference (Matt Brost) - Avoid an integer overflow (Matt Auld) - Address misc review comments by Matt Brost. v9: - Fix a compliation error. - Rebase. v10: - Update to new LRU walk interface. - Rework ghost-, zombie and purged object shrinking. - Rebase. Cc: Christian König Cc: Somalapuram Amaranath Cc: Matthew Brost Cc: Signed-off-by: Thomas Hellström --- drivers/gpu/drm/xe/Makefile | 1 + drivers/gpu/drm/xe/tests/xe_bo.c | 6 +- drivers/gpu/drm/xe/xe_bo.c | 195 +++++++++++++++++++-- drivers/gpu/drm/xe/xe_bo.h | 36 ++++ drivers/gpu/drm/xe/xe_device.c | 8 + drivers/gpu/drm/xe/xe_device_types.h | 2 + drivers/gpu/drm/xe/xe_shrinker.c | 248 +++++++++++++++++++++++++++ drivers/gpu/drm/xe/xe_shrinker.h | 18 ++ 8 files changed, 497 insertions(+), 17 deletions(-) create mode 100644 drivers/gpu/drm/xe/xe_shrinker.c create mode 100644 drivers/gpu/drm/xe/xe_shrinker.h diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile index 8f1c5c329f79..16dbabe71e2d 100644 --- a/drivers/gpu/drm/xe/Makefile +++ b/drivers/gpu/drm/xe/Makefile @@ -93,6 +93,7 @@ xe-y += xe_bb.o \ xe_ring_ops.o \ xe_sa.o \ xe_sched_job.o \ + xe_shrinker.o \ xe_step.o \ xe_sync.o \ xe_tile.o \ diff --git a/drivers/gpu/drm/xe/tests/xe_bo.c b/drivers/gpu/drm/xe/tests/xe_bo.c index 7d3fd720478b..746863cb6e8e 100644 --- a/drivers/gpu/drm/xe/tests/xe_bo.c +++ b/drivers/gpu/drm/xe/tests/xe_bo.c @@ -507,8 +507,13 @@ static int shrink_test_run_device(struct xe_device *xe) * other way around, they may not be subject to swapping... */ if (alloced < purgeable) { + xe_ttm_tt_account_subtract(&xe_tt->ttm); xe_tt->purgeable = true; + xe_ttm_tt_account_add(&xe_tt->ttm); bo->ttm.priority = 0; + spin_lock(&bo->ttm.bdev->lru_lock); + ttm_bo_move_to_lru_tail(&bo->ttm); + spin_unlock(&bo->ttm.bdev->lru_lock); } else { int ret = shrink_test_fill_random(bo, &prng, link); @@ -563,7 +568,6 @@ static int shrink_test_run_device(struct xe_device *xe) if (ret == -EINTR) intr = true; } while (ret == -EINTR && !signal_pending(current)); - if (!ret && !purgeable) failed = shrink_test_verify(test, bo, count, &prng, link); diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c index 5f2f1ec46b57..71245f8c3aa3 100644 --- a/drivers/gpu/drm/xe/xe_bo.c +++ b/drivers/gpu/drm/xe/xe_bo.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -25,6 +26,7 @@ #include "xe_pm.h" #include "xe_preempt_fence.h" #include "xe_res_cursor.h" +#include "xe_shrinker.h" #include "xe_trace_bo.h" #include "xe_ttm_stolen_mgr.h" #include "xe_vm.h" @@ -278,9 +280,11 @@ static void xe_evict_flags(struct ttm_buffer_object *tbo, } } +/* struct xe_ttm_tt - Subclassed ttm_tt for xe */ struct xe_ttm_tt { struct ttm_tt ttm; - struct device *dev; + /** @xe - The xe device */ + struct xe_device *xe; struct sg_table sgt; struct sg_table *sg; /** @purgeable: Whether the content of the pages of @ttm is purgeable. */ @@ -293,7 +297,8 @@ static int xe_tt_map_sg(struct ttm_tt *tt) unsigned long num_pages = tt->num_pages; int ret; - XE_WARN_ON(tt->page_flags & TTM_TT_FLAG_EXTERNAL); + XE_WARN_ON((tt->page_flags & TTM_TT_FLAG_EXTERNAL) && + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)); if (xe_tt->sg) return 0; @@ -301,13 +306,13 @@ static int xe_tt_map_sg(struct ttm_tt *tt) ret = sg_alloc_table_from_pages_segment(&xe_tt->sgt, tt->pages, num_pages, 0, (u64)num_pages << PAGE_SHIFT, - xe_sg_segment_size(xe_tt->dev), + xe_sg_segment_size(xe_tt->xe->drm.dev), GFP_KERNEL); if (ret) return ret; xe_tt->sg = &xe_tt->sgt; - ret = dma_map_sgtable(xe_tt->dev, xe_tt->sg, DMA_BIDIRECTIONAL, + ret = dma_map_sgtable(xe_tt->xe->drm.dev, xe_tt->sg, DMA_BIDIRECTIONAL, DMA_ATTR_SKIP_CPU_SYNC); if (ret) { sg_free_table(xe_tt->sg); @@ -323,7 +328,7 @@ static void xe_tt_unmap_sg(struct ttm_tt *tt) struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); if (xe_tt->sg) { - dma_unmap_sgtable(xe_tt->dev, xe_tt->sg, + dma_unmap_sgtable(xe_tt->xe->drm.dev, xe_tt->sg, DMA_BIDIRECTIONAL, 0); sg_free_table(xe_tt->sg); xe_tt->sg = NULL; @@ -338,21 +343,47 @@ struct sg_table *xe_bo_sg(struct xe_bo *bo) return xe_tt->sg; } +/* + * Account ttm pages against the device shrinker's shrinkable and + * purgeable counts. + */ +static void xe_ttm_tt_account_add(struct ttm_tt *tt) +{ + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); + + if (xe_tt->purgeable) + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, 0, tt->num_pages); + else + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, tt->num_pages, 0); +} + +static void xe_ttm_tt_account_subtract(struct ttm_tt *tt) +{ + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); + + if (xe_tt->purgeable) + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, 0, -(long)tt->num_pages); + else + xe_shrinker_mod_pages(xe_tt->xe->mem.shrinker, -(long)tt->num_pages, 0); +} + static struct ttm_tt *xe_ttm_tt_create(struct ttm_buffer_object *ttm_bo, u32 page_flags) { struct xe_bo *bo = ttm_to_xe_bo(ttm_bo); struct xe_device *xe = xe_bo_device(bo); - struct xe_ttm_tt *tt; + struct xe_ttm_tt *xe_tt; + struct ttm_tt *tt; unsigned long extra_pages; enum ttm_caching caching = ttm_cached; int err; - tt = kzalloc(sizeof(*tt), GFP_KERNEL); - if (!tt) + xe_tt = kzalloc(sizeof(*xe_tt), GFP_KERNEL); + if (!xe_tt) return NULL; - tt->dev = xe->drm.dev; + tt = &xe_tt->ttm; + xe_tt->xe = xe; extra_pages = 0; if (xe_bo_needs_ccs_pages(bo)) @@ -398,42 +429,60 @@ static struct ttm_tt *xe_ttm_tt_create(struct ttm_buffer_object *ttm_bo, caching = ttm_uncached; } - err = ttm_tt_init(&tt->ttm, &bo->ttm, page_flags, caching, extra_pages); + if (ttm_bo->type != ttm_bo_type_sg) + page_flags |= TTM_TT_FLAG_EXTERNAL | TTM_TT_FLAG_EXTERNAL_MAPPABLE; + + err = ttm_tt_init(tt, &bo->ttm, page_flags, caching, extra_pages); if (err) { - kfree(tt); + kfree(xe_tt); + return NULL; + } + + tt->backup = ttm_backup_shmem_create((loff_t)tt->num_pages << PAGE_SHIFT); + if (IS_ERR(tt->backup)) { + tt->backup = NULL; + ttm_tt_fini(tt); + kfree(xe_tt); return NULL; } - return &tt->ttm; + return tt; } static int xe_ttm_tt_populate(struct ttm_device *ttm_dev, struct ttm_tt *tt, struct ttm_operation_ctx *ctx) { + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); int err; /* * dma-bufs are not populated with pages, and the dma- * addresses are set up when moved to XE_PL_TT. */ - if (tt->page_flags & TTM_TT_FLAG_EXTERNAL) + if ((tt->page_flags & TTM_TT_FLAG_EXTERNAL) && + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)) return 0; err = ttm_pool_alloc(&ttm_dev->pool, tt, ctx); if (err) return err; - return err; + xe_tt->purgeable = false; + xe_ttm_tt_account_add(tt); + + return 0; } static void xe_ttm_tt_unpopulate(struct ttm_device *ttm_dev, struct ttm_tt *tt) { - if (tt->page_flags & TTM_TT_FLAG_EXTERNAL) + if ((tt->page_flags & TTM_TT_FLAG_EXTERNAL) && + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE)) return; xe_tt_unmap_sg(tt); - return ttm_pool_free(&ttm_dev->pool, tt); + ttm_pool_free(&ttm_dev->pool, tt); + xe_ttm_tt_account_subtract(tt); } static void xe_ttm_tt_destroy(struct ttm_device *ttm_dev, struct ttm_tt *tt) @@ -854,6 +903,112 @@ static int xe_bo_move(struct ttm_buffer_object *ttm_bo, bool evict, return ret; } +static long xe_bo_shrink_purge(struct ttm_operation_ctx *ctx, + struct ttm_buffer_object *bo, + unsigned long *scanned) +{ + long lret; + + /* Fake move to system, without copying data. */ + if (bo->resource->mem_type != XE_PL_SYSTEM) { + struct ttm_resource *new_resource; + + lret = ttm_bo_wait_ctx(bo, ctx); + if (lret) + return lret; + + lret = ttm_bo_mem_space(bo, &sys_placement, &new_resource, ctx); + if (lret) + return lret; + + xe_tt_unmap_sg(bo->ttm); + ttm_bo_move_null(bo, new_resource); + } + + *scanned += bo->ttm->num_pages; + lret = ttm_bo_try_shrink(ctx, bo, (struct ttm_bo_shrink_flags) + {.purge = true, + .writeback = false, + .allow_move = false}); + + if (lret > 0) + xe_ttm_tt_account_subtract(bo->ttm); + + return lret; +} + +/** + * xe_bo_shrink() - Try to shrink an xe bo. + * @ctx: The struct ttm_operation_ctx used for shrinking. + * @bo: The TTM buffer object whose pages to shrink. + * @flags: Flags governing the shrink behaviour. + * @scanned: Pointer to a counter of the number of pages + * attempted to shrink. + * + * Try to shrink- or purge a bo, and if it succeeds, unmap dma. + * Note that we need to be able to handle also non xe bos + * (ghost bos), but only if the struct ttm_tt is embedded in + * a struct xe_ttm_tt. When the function attempts to shrink + * the pages of a buffer object, The value pointed to by @scanned + * is updated. + * + * Return: The number of pages shrunken or purged, or negative error + * code on failure. + */ +long xe_bo_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, + const struct xe_bo_shrink_flags flags, + unsigned long *scanned) +{ + struct ttm_tt *tt = bo->ttm; + struct xe_ttm_tt *xe_tt = container_of(tt, struct xe_ttm_tt, ttm); + struct ttm_place place = {.mem_type = bo->resource->mem_type}; + struct xe_bo *xe_bo = ttm_to_xe_bo(bo); + struct xe_device *xe = xe_tt->xe; + bool needs_rpm; + long lret = 0L; + + if (!tt || !ttm_tt_is_populated(tt) || + !(tt->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE) || + (flags.purge && !xe_tt->purgeable)) + return 0L; + + if (!ttm_bo_eviction_valuable(bo, &place)) + return 0L; + + if (!xe_bo_is_xe_bo(bo) || !xe_bo_get_unless_zero(xe_bo)) + return xe_bo_shrink_purge(ctx, bo, scanned); + + if (xe_tt->purgeable) { + if (bo->resource->mem_type != XE_PL_SYSTEM) + lret = xe_bo_move_notify(xe_bo, ctx); + if (!lret) + lret = xe_bo_shrink_purge(ctx, bo, scanned); + goto out_unref; + } + + /* System CCS needs gpu copy when moving PL_TT -> PL_SYSTEM */ + needs_rpm = (!IS_DGFX(xe) && bo->resource->mem_type != XE_PL_SYSTEM && + xe_bo_needs_ccs_pages(xe_bo)); + if (needs_rpm && !xe_pm_runtime_get_if_active(xe)) + goto out_unref; + + *scanned += tt->num_pages; + lret = ttm_bo_try_shrink(ctx, bo, (struct ttm_bo_shrink_flags) + {.purge = false, + .writeback = flags.writeback, + .allow_move = true}); + if (needs_rpm) + xe_pm_runtime_put(xe); + + if (lret > 0) + xe_ttm_tt_account_subtract(tt); + +out_unref: + xe_bo_put(xe_bo); + + return lret; +} + /** * xe_bo_evict_pinned() - Evict a pinned VRAM object to system memory * @bo: The buffer object to move. @@ -1737,6 +1892,8 @@ int xe_bo_pin_external(struct xe_bo *bo) } ttm_bo_pin(&bo->ttm); + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) + xe_ttm_tt_account_subtract(bo->ttm.ttm); /* * FIXME: If we always use the reserve / unreserve functions for locking @@ -1795,6 +1952,8 @@ int xe_bo_pin(struct xe_bo *bo) } ttm_bo_pin(&bo->ttm); + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) + xe_ttm_tt_account_subtract(bo->ttm.ttm); /* * FIXME: If we always use the reserve / unreserve functions for locking @@ -1829,6 +1988,8 @@ void xe_bo_unpin_external(struct xe_bo *bo) spin_unlock(&xe->pinned.lock); ttm_bo_unpin(&bo->ttm); + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) + xe_ttm_tt_account_add(bo->ttm.ttm); /* * FIXME: If we always use the reserve / unreserve functions for locking @@ -1857,6 +2018,8 @@ void xe_bo_unpin(struct xe_bo *bo) } ttm_bo_unpin(&bo->ttm); + if (bo->ttm.ttm && ttm_tt_is_populated(bo->ttm.ttm)) + xe_ttm_tt_account_add(bo->ttm.ttm); } /** diff --git a/drivers/gpu/drm/xe/xe_bo.h b/drivers/gpu/drm/xe/xe_bo.h index 6e4be52306df..f2ae1c8ee2eb 100644 --- a/drivers/gpu/drm/xe/xe_bo.h +++ b/drivers/gpu/drm/xe/xe_bo.h @@ -128,6 +128,28 @@ static inline struct xe_bo *xe_bo_get(struct xe_bo *bo) void xe_bo_put(struct xe_bo *bo); +/* + * xe_bo_get_unless_zero() - Conditionally obtain a GEM object refcount on an + * xe bo + * @bo: The bo for which we want to obtain a refcount. + * + * There is a short window between where the bo's GEM object refcount reaches + * zero and where we put the final ttm_bo reference. Code in the eviction- and + * shrinking path should therefore attempt to grab a gem object reference before + * trying to use members outside of the base class ttm object. This function is + * intended for that purpose. On successful return, this function must be paired + * with an xe_bo_put(). + * + * Return: @bo on success, NULL on failure. + */ +static inline __must_check struct xe_bo *xe_bo_get_unless_zero(struct xe_bo *bo) +{ + if (!bo || !kref_get_unless_zero(&bo->ttm.base.refcount)) + return NULL; + + return bo; +} + static inline void __xe_bo_unset_bulk_move(struct xe_bo *bo) { if (bo) @@ -314,6 +336,20 @@ static inline unsigned int xe_sg_segment_size(struct device *dev) #define i915_gem_object_flush_if_display(obj) ((void)(obj)) +/** + * struct xe_bo_shrink_flags - flags governing the shrink behaviour. + * @purge: Only purging allowed. Don't shrink if bo not purgeable. + * @writeback: Attempt to immediately move content to swap. + */ +struct xe_bo_shrink_flags { + u32 purge : 1; + u32 writeback : 1; +}; + +long xe_bo_shrink(struct ttm_operation_ctx *ctx, struct ttm_buffer_object *bo, + const struct xe_bo_shrink_flags flags, + unsigned long *scanned); + #if IS_ENABLED(CONFIG_DRM_XE_KUNIT_TEST) /** * xe_bo_is_mem_type - Whether the bo currently resides in the given diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c index 4d3c794f134c..b2d7b8e11355 100644 --- a/drivers/gpu/drm/xe/xe_device.c +++ b/drivers/gpu/drm/xe/xe_device.c @@ -48,6 +48,7 @@ #include "xe_pcode.h" #include "xe_pm.h" #include "xe_query.h" +#include "xe_shrinker.h" #include "xe_sriov.h" #include "xe_tile.h" #include "xe_ttm_stolen_mgr.h" @@ -297,6 +298,9 @@ static void xe_device_destroy(struct drm_device *dev, void *dummy) if (xe->unordered_wq) destroy_workqueue(xe->unordered_wq); + if (!IS_ERR_OR_NULL(xe->mem.shrinker)) + xe_shrinker_destroy(xe->mem.shrinker); + ttm_device_fini(&xe->ttm); } @@ -326,6 +330,10 @@ struct xe_device *xe_device_create(struct pci_dev *pdev, if (err) goto err; + xe->mem.shrinker = xe_shrinker_create(xe); + if (IS_ERR(xe->mem.shrinker)) + return ERR_CAST(xe->mem.shrinker); + xe->info.devid = pdev->device; xe->info.revid = pdev->revision; xe->info.force_execlist = xe_modparam.force_execlist; diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h index c92df0a2423f..610f262fcd7d 100644 --- a/drivers/gpu/drm/xe/xe_device_types.h +++ b/drivers/gpu/drm/xe/xe_device_types.h @@ -365,6 +365,8 @@ struct xe_device { struct xe_mem_region vram; /** @mem.sys_mgr: system TTM manager */ struct ttm_resource_manager sys_mgr; + /** @mem.sys_mgr: system memory shrinker. */ + struct xe_shrinker *shrinker; } mem; /** @sriov: device level virtualization data */ diff --git a/drivers/gpu/drm/xe/xe_shrinker.c b/drivers/gpu/drm/xe/xe_shrinker.c new file mode 100644 index 000000000000..32f83316146c --- /dev/null +++ b/drivers/gpu/drm/xe/xe_shrinker.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2024 Intel Corporation + */ + +#include +#include + +#include +#include + +#include "xe_bo.h" +#include "xe_pm.h" +#include "xe_shrinker.h" + +/** + * struct xe_shrinker - per-device shrinker + * @xe: Back pointer to the device. + * @lock: Lock protecting accounting. + * @shrinkable_pages: Number of pages that are currently shrinkable. + * @purgeable_pages: Number of pages that are currently purgeable. + * @shrink: Pointer to the mm shrinker. + * @pm_worker: Worker to wake up the device if required. + */ +struct xe_shrinker { + struct xe_device *xe; + rwlock_t lock; + long shrinkable_pages; + long purgeable_pages; + struct shrinker *shrink; + struct work_struct pm_worker; +}; + +static struct xe_shrinker *to_xe_shrinker(struct shrinker *shrink) +{ + return shrink->private_data; +} + +/** + * xe_shrinker_mod_pages() - Modify shrinker page accounting + * @shrinker: Pointer to the struct xe_shrinker. + * @shrinkable: Shrinkable pages delta. May be negative. + * @purgeable: Purgeable page delta. May be negative. + * + * Modifies the shrinkable and purgeable pages accounting. + */ +void +xe_shrinker_mod_pages(struct xe_shrinker *shrinker, long shrinkable, long purgeable) +{ + write_lock(&shrinker->lock); + shrinker->shrinkable_pages += shrinkable; + shrinker->purgeable_pages += purgeable; + write_unlock(&shrinker->lock); +} + +static s64 xe_shrinker_walk(struct xe_device *xe, + struct ttm_operation_ctx *ctx, + const struct xe_bo_shrink_flags flags, + unsigned long to_scan, unsigned long *scanned) +{ + unsigned int mem_type; + s64 freed = 0, lret; + + for (mem_type = XE_PL_SYSTEM; mem_type <= XE_PL_TT; ++mem_type) { + struct ttm_resource_manager *man = ttm_manager_type(&xe->ttm, mem_type); + struct ttm_bo_lru_cursor curs; + struct ttm_buffer_object *ttm_bo; + + if (!man || !man->use_tt) + continue; + + ttm_bo_lru_for_each_reserved_guarded(&curs, man, ctx, ttm_bo) { + lret = xe_bo_shrink(ctx, ttm_bo, flags, scanned); + if (lret < 0) + return lret; + + freed += lret; + if (*scanned >= to_scan) + break; + } + } + + return freed; +} + +static unsigned long +xe_shrinker_count(struct shrinker *shrink, struct shrink_control *sc) +{ + struct xe_shrinker *shrinker = to_xe_shrinker(shrink); + unsigned long num_pages; + + num_pages = get_nr_swap_pages(); + read_lock(&shrinker->lock); + num_pages = min_t(unsigned long, num_pages, shrinker->shrinkable_pages); + num_pages += shrinker->purgeable_pages; + read_unlock(&shrinker->lock); + + return num_pages ? num_pages : SHRINK_EMPTY; +} + +/* + * Check if we need runtime pm, and if so try to grab a reference if + * already active. If grabbing a reference fails, queue a worker that + * does it for us outside of reclaim, but don't wait for it to complete. + * If bo shrinking needs an rpm reference and we don't have it (yet), + * that bo will be skipped anyway. + */ +static bool xe_shrinker_runtime_pm_get(struct xe_shrinker *shrinker, bool force, + unsigned long nr_to_scan) +{ + struct xe_device *xe = shrinker->xe; + + if (IS_DGFX(xe) || !xe_device_has_flat_ccs(xe) || + !get_nr_swap_pages()) + return false; + + if (!force) { + read_lock(&shrinker->lock); + force = (nr_to_scan > shrinker->purgeable_pages); + read_unlock(&shrinker->lock); + if (!force) + return false; + } + + if (!xe_pm_runtime_get_if_active(xe)) { + if (xe_rpm_reclaim_safe(xe) && current_is_kswapd()) { + xe_pm_runtime_get(xe); + return true; + } + queue_work(xe->unordered_wq, &shrinker->pm_worker); + return false; + } + + return true; +} + +static void xe_shrinker_runtime_pm_put(struct xe_shrinker *shrinker, bool runtime_pm) +{ + if (runtime_pm) + xe_pm_runtime_put(shrinker->xe); +} + +static unsigned long xe_shrinker_scan(struct shrinker *shrink, struct shrink_control *sc) +{ + struct xe_shrinker *shrinker = to_xe_shrinker(shrink); + bool is_kswapd = current_is_kswapd(); + struct ttm_operation_ctx ctx = { + .interruptible = false, + .no_wait_gpu = !is_kswapd, + }; + unsigned long nr_to_scan, nr_scanned = 0, freed = 0; + struct xe_bo_shrink_flags shrink_flags = { + .purge = true, + .writeback = is_kswapd, + }; + bool runtime_pm; + bool purgeable; + s64 lret; + + nr_to_scan = sc->nr_to_scan; + + read_lock(&shrinker->lock); + purgeable = !!shrinker->purgeable_pages; + read_unlock(&shrinker->lock); + + /* Might need runtime PM. Try to wake early if it looks like it. */ + runtime_pm = xe_shrinker_runtime_pm_get(shrinker, false, nr_to_scan); + + if (purgeable && nr_scanned < nr_to_scan) { + lret = xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, + nr_to_scan, &nr_scanned); + if (lret >= 0) + freed += lret; + } + + sc->nr_scanned = nr_scanned; + if (nr_scanned >= nr_to_scan) + goto out; + + /* If we didn't wake before, try to do it now if needed. */ + if (!runtime_pm) + runtime_pm = xe_shrinker_runtime_pm_get(shrinker, true, 0); + + shrink_flags.purge = false; + lret = xe_shrinker_walk(shrinker->xe, &ctx, shrink_flags, + nr_to_scan, &nr_scanned); + if (lret >= 0) + freed += lret; + + sc->nr_scanned = nr_scanned; +out: + xe_shrinker_runtime_pm_put(shrinker, runtime_pm); + return nr_scanned ? freed : SHRINK_STOP; +} + +/* Wake up the device for shrinking. */ +static void xe_shrinker_pm(struct work_struct *work) +{ + struct xe_shrinker *shrinker = + container_of(work, typeof(*shrinker), pm_worker); + + xe_pm_runtime_get(shrinker->xe); + xe_pm_runtime_put(shrinker->xe); +} + +/** + * xe_shrinker_create() - Create an xe per-device shrinker + * @xe: Pointer to the xe device. + * + * Returns: A pointer to the created shrinker on success, + * Negative error code on failure. + */ +struct xe_shrinker *xe_shrinker_create(struct xe_device *xe) +{ + struct xe_shrinker *shrinker = kzalloc(sizeof(*shrinker), GFP_KERNEL); + + if (!shrinker) + return ERR_PTR(-ENOMEM); + + shrinker->shrink = shrinker_alloc(0, "xe system shrinker"); + if (!shrinker->shrink) { + kfree(shrinker); + return ERR_PTR(-ENOMEM); + } + + INIT_WORK(&shrinker->pm_worker, xe_shrinker_pm); + shrinker->xe = xe; + rwlock_init(&shrinker->lock); + shrinker->shrink->count_objects = xe_shrinker_count; + shrinker->shrink->scan_objects = xe_shrinker_scan; + shrinker->shrink->private_data = shrinker; + shrinker_register(shrinker->shrink); + + return shrinker; +} + +/** + * xe_shrinker_destroy() - Destroy an xe per-device shrinker + * @shrinker: Pointer to the shrinker to destroy. + */ +void xe_shrinker_destroy(struct xe_shrinker *shrinker) +{ + xe_assert(shrinker->xe, !shrinker->shrinkable_pages); + xe_assert(shrinker->xe, !shrinker->purgeable_pages); + shrinker_free(shrinker->shrink); + flush_work(&shrinker->pm_worker); + kfree(shrinker); +} diff --git a/drivers/gpu/drm/xe/xe_shrinker.h b/drivers/gpu/drm/xe/xe_shrinker.h new file mode 100644 index 000000000000..28a038f4fcbf --- /dev/null +++ b/drivers/gpu/drm/xe/xe_shrinker.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: MIT */ +/* + * Copyright © 2024 Intel Corporation + */ + +#ifndef _XE_SHRINKER_H_ +#define _XE_SHRINKER_H_ + +struct xe_shrinker; +struct xe_device; + +void xe_shrinker_mod_pages(struct xe_shrinker *shrinker, long shrinkable, long purgeable); + +struct xe_shrinker *xe_shrinker_create(struct xe_device *xe); + +void xe_shrinker_destroy(struct xe_shrinker *shrinker); + +#endif From patchwork Mon Sep 16 14:51:12 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Thomas_Hellstr=C3=B6m?= X-Patchwork-Id: 13805556 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 16A7BC3ABD2 for ; 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([10.245.244.45]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2024 07:51:53 -0700 From: =?utf-8?q?Thomas_Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org Cc: =?utf-8?q?Thomas_Hellstr=C3=B6m?= , Matthew Brost , Somalapuram Amaranath , =?utf-8?q?Christian_?= =?utf-8?q?K=C3=B6nig?= , Paulo Zanoni , Simona Vetter , dri-devel@lists.freedesktop.org Subject: [PATCH v10 7/7] drm/xe: Increase the XE_PL_TT watermark Date: Mon, 16 Sep 2024 16:51:12 +0200 Message-ID: <20240916145112.3336-8-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240916145112.3336-1-thomas.hellstrom@linux.intel.com> References: <20240916145112.3336-1-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" The XE_PL_TT watermark was set to 50% of system memory. The idea behind that was unclear since the net effect is that TT memory will be evicted to TTM_PL_SYSTEM memory if that watermark is exceeded, requiring PPGTT rebinds and dma remapping. But there is no similar watermark for TTM_PL_1SYSTEM memory. The TTM functionality that tries to swap out system memory to shmem objects if a 50% limit of total system memory is reached is orthogonal to this, and with the shrinker added, it's no longer in effect. Replace the 50% TTM_PL_TT limit with a 100% limit, in effect allowing all graphics memory to be bound to the device unless it has been swapped out by the shrinker. Signed-off-by: Thomas Hellström Reviewed-by: Matthew Brost --- drivers/gpu/drm/xe/xe_ttm_sys_mgr.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_ttm_sys_mgr.c b/drivers/gpu/drm/xe/xe_ttm_sys_mgr.c index 9844a8edbfe1..d38b91872da3 100644 --- a/drivers/gpu/drm/xe/xe_ttm_sys_mgr.c +++ b/drivers/gpu/drm/xe/xe_ttm_sys_mgr.c @@ -108,9 +108,8 @@ int xe_ttm_sys_mgr_init(struct xe_device *xe) u64 gtt_size; si_meminfo(&si); + /* Potentially restrict amount of TT memory here. */ gtt_size = (u64)si.totalram * si.mem_unit; - /* TTM limits allocation of all TTM devices by 50% of system memory */ - gtt_size /= 2; man->use_tt = true; man->func = &xe_ttm_sys_mgr_func;