From patchwork Thu Jan 26 11:57:49 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A . Shutemov" X-Patchwork-Id: 9539137 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id CDC72601D7 for ; Thu, 26 Jan 2017 12:08:25 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C375627D13 for ; Thu, 26 Jan 2017 12:08:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B7E19281C3; Thu, 26 Jan 2017 12:08:25 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0CFE427D13 for ; Thu, 26 Jan 2017 12:08:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753321AbdAZMIG (ORCPT ); Thu, 26 Jan 2017 07:08:06 -0500 Received: from mga05.intel.com ([192.55.52.43]:60730 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753116AbdAZL65 (ORCPT ); Thu, 26 Jan 2017 06:58:57 -0500 Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga105.fm.intel.com with ESMTP; 26 Jan 2017 03:58:36 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,289,1477983600"; d="scan'208";a="926869242" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga003.jf.intel.com with ESMTP; 26 Jan 2017 03:58:31 -0800 Received: by black.fi.intel.com (Postfix, from userid 1000) id 73A8C1EE; Thu, 26 Jan 2017 13:58:25 +0200 (EET) 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, "Kirill A. Shutemov" Subject: [PATCHv6 07/37] filemap: allocate huge page in page_cache_read(), if allowed Date: Thu, 26 Jan 2017 14:57:49 +0300 Message-Id: <20170126115819.58875-8-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170126115819.58875-1-kirill.shutemov@linux.intel.com> References: <20170126115819.58875-1-kirill.shutemov@linux.intel.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds basic functionality to put huge page into page cache. At the moment we only put huge pages into radix-tree if the range covered by the huge page is empty. We ignore shadow entires for now, just remove them from the tree before inserting huge page. Later we can add logic to accumulate information from shadow entires to return to caller (average eviction time?). Signed-off-by: Kirill A. Shutemov Reviewed-by: Matthew Wilcox --- include/linux/fs.h | 5 ++ include/linux/pagemap.h | 21 ++++++- mm/filemap.c | 155 ++++++++++++++++++++++++++++++++++++++---------- 3 files changed, 147 insertions(+), 34 deletions(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index 2ba074328894..dd858a858203 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1806,6 +1806,11 @@ struct super_operations { #else #define S_DAX 0 /* Make all the DAX code disappear */ #endif +#define S_HUGE_MODE 0xc000 +#define S_HUGE_NEVER 0x0000 +#define S_HUGE_ALWAYS 0x4000 +#define S_HUGE_WITHIN_SIZE 0x8000 +#define S_HUGE_ADVISE 0xc000 /* * Note that nosuid etc flags are inode-specific: setting some file-system diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index ad63a7be5a5e..9a93b9c3d662 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -201,14 +201,20 @@ static inline int page_cache_add_speculative(struct page *page, int count) } #ifdef CONFIG_NUMA -extern struct page *__page_cache_alloc(gfp_t gfp); +extern struct page *__page_cache_alloc_order(gfp_t gfp, unsigned int order); #else -static inline struct page *__page_cache_alloc(gfp_t gfp) +static inline struct page *__page_cache_alloc_order(gfp_t gfp, + unsigned int order) { - return alloc_pages(gfp, 0); + return alloc_pages(gfp, order); } #endif +static inline struct page *__page_cache_alloc(gfp_t gfp) +{ + return __page_cache_alloc_order(gfp, 0); +} + static inline struct page *page_cache_alloc(struct address_space *x) { return __page_cache_alloc(mapping_gfp_mask(x)); @@ -225,6 +231,15 @@ static inline gfp_t readahead_gfp_mask(struct address_space *x) __GFP_COLD | __GFP_NORETRY | __GFP_NOWARN; } +extern bool __page_cache_allow_huge(struct address_space *x, pgoff_t offset); +static inline bool page_cache_allow_huge(struct address_space *x, + pgoff_t offset) +{ + if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) + return false; + return __page_cache_allow_huge(x, offset); +} + typedef int filler_t(void *, struct page *); pgoff_t page_cache_next_hole(struct address_space *mapping, diff --git a/mm/filemap.c b/mm/filemap.c index 5c8d912e891d..301327685a71 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -113,37 +113,50 @@ static int page_cache_tree_insert(struct address_space *mapping, struct page *page, void **shadowp) { - struct radix_tree_node *node; - void **slot; + struct radix_tree_iter iter; + void **slot, *p; int error; - error = __radix_tree_create(&mapping->page_tree, page->index, 0, - &node, &slot); - if (error) - return error; - if (*slot) { - void *p; + /* Wipe shadow entires */ + radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, + page->index) { + if (iter.index >= page->index + hpage_nr_pages(page)) + break; p = radix_tree_deref_slot_protected(slot, &mapping->tree_lock); - if (!radix_tree_exceptional_entry(p)) + if (!p) + continue; + + if (!radix_tree_exception(p)) return -EEXIST; + __radix_tree_replace(&mapping->page_tree, iter.node, slot, NULL, + workingset_update_node, mapping); + mapping->nrexceptional--; - if (!dax_mapping(mapping)) { - if (shadowp) - *shadowp = p; - } else { + if (dax_mapping(mapping)) { /* DAX can replace empty locked entry with a hole */ WARN_ON_ONCE(p != dax_radix_locked_entry(0, RADIX_DAX_EMPTY)); /* Wakeup waiters for exceptional entry lock */ dax_wake_mapping_entry_waiter(mapping, page->index, p, true); + } else if (!PageTransHuge(page) && shadowp) { + *shadowp = p; } } - __radix_tree_replace(&mapping->page_tree, node, slot, page, - workingset_update_node, mapping); - mapping->nrpages++; + + error = __radix_tree_insert(&mapping->page_tree, + page->index, compound_order(page), page); + /* This shouldn't happen */ + if (WARN_ON_ONCE(error)) + return error; + + mapping->nrpages += hpage_nr_pages(page); + if (PageTransHuge(page) && !PageHuge(page)) { + count_vm_event(THP_FILE_ALLOC); + __inc_node_page_state(page, NR_FILE_THPS); + } return 0; } @@ -600,14 +613,14 @@ static int __add_to_page_cache_locked(struct page *page, pgoff_t offset, gfp_t gfp_mask, void **shadowp) { - int huge = PageHuge(page); + int hugetlb = PageHuge(page); struct mem_cgroup *memcg; int error; VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageSwapBacked(page), page); - if (!huge) { + if (!hugetlb) { error = mem_cgroup_try_charge(page, current->mm, gfp_mask, &memcg, false); if (error) @@ -616,7 +629,7 @@ static int __add_to_page_cache_locked(struct page *page, error = radix_tree_maybe_preload(gfp_mask & ~__GFP_HIGHMEM); if (error) { - if (!huge) + if (!hugetlb) mem_cgroup_cancel_charge(page, memcg, false); return error; } @@ -632,10 +645,11 @@ static int __add_to_page_cache_locked(struct page *page, goto err_insert; /* hugetlb pages do not participate in page cache accounting. */ - if (!huge) - __inc_node_page_state(page, NR_FILE_PAGES); + if (!hugetlb) + __mod_node_page_state(page_pgdat(page), NR_FILE_PAGES, + hpage_nr_pages(page)); spin_unlock_irq(&mapping->tree_lock); - if (!huge) + if (!hugetlb) mem_cgroup_commit_charge(page, memcg, false, false); trace_mm_filemap_add_to_page_cache(page); return 0; @@ -643,7 +657,7 @@ static int __add_to_page_cache_locked(struct page *page, page->mapping = NULL; /* Leave page->index set: truncation relies upon it */ spin_unlock_irq(&mapping->tree_lock); - if (!huge) + if (!hugetlb) mem_cgroup_cancel_charge(page, memcg, false); put_page(page); return error; @@ -700,7 +714,7 @@ int add_to_page_cache_lru(struct page *page, struct address_space *mapping, EXPORT_SYMBOL_GPL(add_to_page_cache_lru); #ifdef CONFIG_NUMA -struct page *__page_cache_alloc(gfp_t gfp) +struct page *__page_cache_alloc_order(gfp_t gfp, unsigned int order) { int n; struct page *page; @@ -710,14 +724,14 @@ struct page *__page_cache_alloc(gfp_t gfp) do { cpuset_mems_cookie = read_mems_allowed_begin(); n = cpuset_mem_spread_node(); - page = __alloc_pages_node(n, gfp, 0); + page = __alloc_pages_node(n, gfp, order); } while (!page && read_mems_allowed_retry(cpuset_mems_cookie)); return page; } - return alloc_pages(gfp, 0); + return alloc_pages(gfp, order); } -EXPORT_SYMBOL(__page_cache_alloc); +EXPORT_SYMBOL(__page_cache_alloc_order); #endif /* @@ -1239,6 +1253,69 @@ struct page *find_lock_entry(struct address_space *mapping, pgoff_t offset) } EXPORT_SYMBOL(find_lock_entry); +bool __page_cache_allow_huge(struct address_space *mapping, pgoff_t offset) +{ + struct inode *inode = mapping->host; + struct radix_tree_iter iter; + void **slot; + struct page *page; + + if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE)) + return false; + + offset = round_down(offset, HPAGE_PMD_NR); + + switch (inode->i_flags & S_HUGE_MODE) { + case S_HUGE_NEVER: + return false; + case S_HUGE_ALWAYS: + break; + case S_HUGE_WITHIN_SIZE: + if (DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE) < + offset + HPAGE_PMD_NR) + return false; + break; + case S_HUGE_ADVISE: + /* TODO */ + return false; + default: + WARN_ON_ONCE(1); + return false; + } + + rcu_read_lock(); + radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, offset) { + if (iter.index >= offset + HPAGE_PMD_NR) + break; + + /* Shadow entires are fine */ + page = radix_tree_deref_slot(slot); + if (page && !radix_tree_exception(page)) { + rcu_read_unlock(); + return false; + } + } + rcu_read_unlock(); + + return true; + +} + +static struct page *page_cache_alloc_huge(struct address_space *mapping, + pgoff_t offset, gfp_t gfp_mask) +{ + struct page *page; + + if (!page_cache_allow_huge(mapping, offset)) + return NULL; + + gfp_mask |= __GFP_COMP | __GFP_NORETRY | __GFP_NOWARN; + page = __page_cache_alloc_order(gfp_mask, HPAGE_PMD_ORDER); + if (page) + prep_transhuge_page(page); + return page; +} + /** * pagecache_get_page - find and get a page reference * @mapping: the address_space to search @@ -2078,18 +2155,34 @@ static int page_cache_read(struct file *file, pgoff_t offset, gfp_t gfp_mask) { struct address_space *mapping = file->f_mapping; struct page *page; + pgoff_t hoffset; int ret; do { - page = __page_cache_alloc(gfp_mask|__GFP_COLD); + page = page_cache_alloc_huge(mapping, offset, gfp_mask); +no_huge: + if (!page) + page = __page_cache_alloc(gfp_mask|__GFP_COLD); if (!page) return -ENOMEM; - ret = add_to_page_cache_lru(page, mapping, offset, gfp_mask & GFP_KERNEL); - if (ret == 0) + if (PageTransHuge(page)) + hoffset = round_down(offset, HPAGE_PMD_NR); + else + hoffset = offset; + + ret = add_to_page_cache_lru(page, mapping, hoffset, + gfp_mask & GFP_KERNEL); + + if (ret == -EEXIST && PageTransHuge(page)) { + put_page(page); + page = NULL; + goto no_huge; + } else if (ret == 0) { ret = mapping->a_ops->readpage(file, page); - else if (ret == -EEXIST) + } else if (ret == -EEXIST) { ret = 0; /* losing race to add is OK */ + } put_page(page);