From patchwork Thu Sep 15 11:54:47 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A. Shutemov" X-Patchwork-Id: 670334 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3sZcQS64wMz9s9N for ; Thu, 15 Sep 2016 21:59:12 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934754AbcIOL4k (ORCPT ); Thu, 15 Sep 2016 07:56:40 -0400 Received: from mga14.intel.com ([192.55.52.115]:38877 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934569AbcIOL4g (ORCPT ); Thu, 15 Sep 2016 07:56:36 -0400 Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga103.fm.intel.com with ESMTP; 15 Sep 2016 04:56:36 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.30,339,1470726000"; d="scan'208";a="1056442672" Received: from black.fi.intel.com ([10.237.72.56]) by fmsmga002.fm.intel.com with ESMTP; 15 Sep 2016 04:56:32 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 34C5F49E; Thu, 15 Sep 2016 14:55:26 +0300 (EEST) From: "Kirill A. Shutemov" To: "Theodore Ts'o" , Andreas Dilger , Jan Kara , Andrew Morton Cc: Alexander Viro , Hugh Dickins , Andrea Arcangeli , Dave Hansen , Vlastimil Babka , Matthew Wilcox , Ross Zwisler , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org, Matthew Wilcox , "Kirill A . Shutemov" Subject: [PATCHv3 05/41] radix-tree: Add radix_tree_split_preload() Date: Thu, 15 Sep 2016 14:54:47 +0300 Message-Id: <20160915115523.29737-6-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20160915115523.29737-1-kirill.shutemov@linux.intel.com> References: <20160915115523.29737-1-kirill.shutemov@linux.intel.com> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org From: Matthew Wilcox Calculate how many nodes we need to allocate to split an old_order entry into multiple entries, each of size new_order. The test suite checks that we allocated exactly the right number of nodes; neither too many (checked by rtp->nr == 0), nor too few (checked by comparing nr_allocated before and after the call to radix_tree_split()). Signed-off-by: Matthew Wilcox Signed-off-by: Kirill A. Shutemov --- include/linux/radix-tree.h | 1 + lib/radix-tree.c | 22 ++++++++++++++++++++++ tools/testing/radix-tree/multiorder.c | 28 ++++++++++++++++++++++++++-- tools/testing/radix-tree/test.h | 9 +++++++++ 4 files changed, 58 insertions(+), 2 deletions(-) diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h index 459e8a152c8a..c4cea311d901 100644 --- a/include/linux/radix-tree.h +++ b/include/linux/radix-tree.h @@ -318,6 +318,7 @@ static inline void radix_tree_preload_end(void) preempt_enable(); } +int radix_tree_split_preload(unsigned old_order, unsigned new_order, gfp_t); int radix_tree_split(struct radix_tree_root *, unsigned long index, unsigned new_order); int radix_tree_join(struct radix_tree_root *, unsigned long index, diff --git a/lib/radix-tree.c b/lib/radix-tree.c index ad3116cbe61b..e58855435c01 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -410,6 +410,28 @@ int radix_tree_maybe_preload(gfp_t gfp_mask) } EXPORT_SYMBOL(radix_tree_maybe_preload); +#ifdef CONFIG_RADIX_TREE_MULTIORDER +/* + * Preload with enough objects to ensure that we can split a single entry + * of order @old_order into many entries of size @new_order + */ +int radix_tree_split_preload(unsigned int old_order, unsigned int new_order, + gfp_t gfp_mask) +{ + unsigned top = 1 << (old_order % RADIX_TREE_MAP_SHIFT); + unsigned layers = (old_order / RADIX_TREE_MAP_SHIFT) - + (new_order / RADIX_TREE_MAP_SHIFT); + unsigned nr = 0; + + WARN_ON_ONCE(!gfpflags_allow_blocking(gfp_mask)); + BUG_ON(new_order >= old_order); + + while (layers--) + nr = nr * RADIX_TREE_MAP_SIZE + 1; + return __radix_tree_preload(gfp_mask, top * nr); +} +#endif + /* * The same as function above, but preload number of nodes required to insert * (1 << order) continuous naturally-aligned elements. diff --git a/tools/testing/radix-tree/multiorder.c b/tools/testing/radix-tree/multiorder.c index 9d27a4dd7b2a..5eda47dfe818 100644 --- a/tools/testing/radix-tree/multiorder.c +++ b/tools/testing/radix-tree/multiorder.c @@ -348,18 +348,42 @@ static void multiorder_join(void) } } +static void check_mem(unsigned old_order, unsigned new_order, unsigned alloc) +{ + struct radix_tree_preload *rtp = &radix_tree_preloads; + if (rtp->nr != 0) + printf("split(%u %u) remaining %u\n", old_order, new_order, + rtp->nr); + /* + * Can't check for equality here as some nodes may have been + * RCU-freed while we ran. But we should never finish with more + * nodes allocated since they should have all been preloaded. + */ + if (nr_allocated > alloc) + printf("split(%u %u) allocated %u %u\n", old_order, new_order, + alloc, nr_allocated); +} + static void __multiorder_split(int old_order, int new_order) { - RADIX_TREE(tree, GFP_KERNEL); + RADIX_TREE(tree, GFP_ATOMIC); void **slot; struct radix_tree_iter iter; + unsigned alloc; - item_insert_order(&tree, 0, old_order); + radix_tree_preload(GFP_KERNEL); + assert(item_insert_order(&tree, 0, old_order) == 0); + radix_tree_callback(NULL, CPU_DEAD, NULL); radix_tree_tag_set(&tree, 0, 2); + + radix_tree_split_preload(old_order, new_order, GFP_KERNEL); + alloc = nr_allocated; radix_tree_split(&tree, 0, new_order); + check_mem(old_order, new_order, alloc); radix_tree_for_each_slot(slot, &tree, &iter, 0) { radix_tree_replace_slot(slot, item_create(iter.index)); } + radix_tree_preload_end(); item_kill_tree(&tree); } diff --git a/tools/testing/radix-tree/test.h b/tools/testing/radix-tree/test.h index e85131369723..55e6d095047b 100644 --- a/tools/testing/radix-tree/test.h +++ b/tools/testing/radix-tree/test.h @@ -2,6 +2,8 @@ #include #include #include +#include +#include struct item { unsigned long index; @@ -43,3 +45,10 @@ void radix_tree_dump(struct radix_tree_root *root); int root_tag_get(struct radix_tree_root *root, unsigned int tag); unsigned long node_maxindex(struct radix_tree_node *); unsigned long shift_maxindex(unsigned int shift); +int radix_tree_callback(struct notifier_block *nfb, + unsigned long action, void *hcpu); +struct radix_tree_preload { + unsigned nr; + struct radix_tree_node *nodes; +}; +extern struct radix_tree_preload radix_tree_preloads;