From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: [PATCH v10 28/62] mm: Convert add_to_swap_cache to XArray Date: Thu, 29 Mar 2018 20:42:11 -0700 Message-ID: <20180330034245.10462-29-willy@infradead.org> References: <20180330034245.10462-1-willy@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=References:In-Reply-To:Message-Id:Date:Subject:Cc: To:From:Sender:Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=EitFpxCHyrBctILPY1Gqn8vUBzM30gE+xJAMsmpJzt8=; b=mJosdOrkghDh1FOoYWGXBrNjdE XqbhhWRCtjP9Wtc1FM18awBv6DRhS9juRgZP58yzpU53gWCAVliu0UJyc2en5Ry58APtXeYMM8Sbl sdu65KSErTzVQUOsDW9nzvhaboQ4bg0n2BdU1IMNbtAMYKXGBM56abe/7gfiZaVnHmGc=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To :MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=EitFpxCHyrBctILPY1Gqn8vUBzM30gE+xJAMsmpJzt8=; b=Sssvn6WZh1qJv3an2U0p/Y81Xn KFMgmm1HRtLd5sjZRuWsDNhCi0uH1T8ltXWUdzNyXFiIT7jOLvhITrX+h35Ft709OIlO1lZEpifR/ NAPUKVpFznBDGPeuNeWBVRXpfJP+S/95vVBalsWLEOPIdCapv/yRct6G6v1hvvrz3QNo=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=References:In-Reply-To:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=EitFpxCHyrBctILPY1Gqn8vUBzM30gE+xJAMsmpJzt8=; b=qUaUWqvAfw08PLEnCrJ/nzJ35 MWNvaIzcbXdCPKWXCtR4TFGT7jfTthZZaTGwlC/WdLGBkRk4pt6XlGHuNKKeofOugHyydWruQs5kF iuPskj83ta2qrEA0GjRBjyzWQydNKtfZeBLs/p8QM+HsNciaIZY49zLq06pPa1HCWDBR1tZt6EQy2 rmlxvSBHTR77XzUz9G/lT0C/GY0Bb3Ys+vwU0yKPS4XRkkwjzrgEJj2k5AajXQH6OamkGmBpwNa9c QYMT8s0c9NnHzh1+4v5OwVLiwi3UoqIBAP2lXQ5N33mIxOUZrdQaO9RQdj+QlZkhsv/6zAyv9x5bN 5eDoTXO7A==; In-Reply-To: <20180330034245.10462-1-willy@infradead.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org Cc: linux-nilfs@vger.kernel.org, Jan Kara , Jeff Layton , Matthew Wilcox , James Simmons , Jaegeuk Kim , Andreas Dilger , Nicholas Piggin , linux-f2fs-devel@lists.sourceforge.net, Oleg Drokin , Ryusuke Konishi , Lukas Czerner , Ross Zwisler , Christoph Hellwig , Goldwyn Rodrigues , Mike Kravetz From: Matthew Wilcox Combine __add_to_swap_cache and add_to_swap_cache into one function since there is no more need to preload. Signed-off-by: Matthew Wilcox --- mm/swap_state.c | 93 ++++++++++++++++++--------------------------------------- 1 file changed, 29 insertions(+), 64 deletions(-) diff --git a/mm/swap_state.c b/mm/swap_state.c index fe079756bb18..53e27894c1bc 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -107,14 +107,15 @@ void show_swap_cache_info(void) } /* - * __add_to_swap_cache resembles add_to_page_cache_locked on swapper_space, + * add_to_swap_cache resembles add_to_page_cache_locked on swapper_space, * but sets SwapCache flag and private instead of mapping and index. */ -int __add_to_swap_cache(struct page *page, swp_entry_t entry) +int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp) { - int error, i, nr = hpage_nr_pages(page); - struct address_space *address_space; + struct address_space *address_space = swap_address_space(entry); pgoff_t idx = swp_offset(entry); + XA_STATE(xas, &address_space->i_pages, idx); + unsigned long i, nr = 1UL << compound_order(page); VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageSwapCache(page), page); @@ -123,50 +124,30 @@ int __add_to_swap_cache(struct page *page, swp_entry_t entry) page_ref_add(page, nr); SetPageSwapCache(page); - address_space = swap_address_space(entry); - xa_lock_irq(&address_space->i_pages); - for (i = 0; i < nr; i++) { - set_page_private(page + i, entry.val + i); - error = radix_tree_insert(&address_space->i_pages, - idx + i, page + i); - if (unlikely(error)) - break; - } - if (likely(!error)) { + do { + xas_lock_irq(&xas); + xas_create_range(&xas, idx + nr - 1); + if (xas_error(&xas)) + goto unlock; + for (i = 0; i < nr; i++) { + VM_BUG_ON_PAGE(xas.xa_index != idx + i, page); + set_page_private(page + i, entry.val + i); + xas_store(&xas, page + i); + xas_next(&xas); + } address_space->nrpages += nr; __mod_node_page_state(page_pgdat(page), NR_FILE_PAGES, nr); ADD_CACHE_INFO(add_total, nr); - } else { - /* - * Only the context which have set SWAP_HAS_CACHE flag - * would call add_to_swap_cache(). - * So add_to_swap_cache() doesn't returns -EEXIST. - */ - VM_BUG_ON(error == -EEXIST); - set_page_private(page + i, 0UL); - while (i--) { - radix_tree_delete(&address_space->i_pages, idx + i); - set_page_private(page + i, 0UL); - } - ClearPageSwapCache(page); - page_ref_sub(page, nr); - } - xa_unlock_irq(&address_space->i_pages); +unlock: + xas_unlock_irq(&xas); + } while (xas_nomem(&xas, gfp)); - return error; -} - - -int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask) -{ - int error; + if (!xas_error(&xas)) + return 0; - error = radix_tree_maybe_preload_order(gfp_mask, compound_order(page)); - if (!error) { - error = __add_to_swap_cache(page, entry); - radix_tree_preload_end(); - } - return error; + ClearPageSwapCache(page); + page_ref_sub(page, nr); + return xas_error(&xas); } /* @@ -220,7 +201,7 @@ int add_to_swap(struct page *page) goto fail; /* - * Radix-tree node allocations from PF_MEMALLOC contexts could + * XArray node allocations from PF_MEMALLOC contexts could * completely exhaust the page allocator. __GFP_NOMEMALLOC * stops emergency reserves from being allocated. * @@ -232,7 +213,6 @@ int add_to_swap(struct page *page) */ err = add_to_swap_cache(page, entry, __GFP_HIGH|__GFP_NOMEMALLOC|__GFP_NOWARN); - /* -ENOMEM radix-tree allocation failure */ if (err) /* * add_to_swap_cache() doesn't return -EEXIST, so we can safely @@ -426,19 +406,11 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, break; /* Out of memory */ } - /* - * call radix_tree_preload() while we can wait. - */ - err = radix_tree_maybe_preload(gfp_mask & GFP_KERNEL); - if (err) - break; - /* * Swap entry may have been freed since our caller observed it. */ err = swapcache_prepare(entry); if (err == -EEXIST) { - radix_tree_preload_end(); /* * We might race against get_swap_page() and stumble * across a SWAP_HAS_CACHE swap_map entry whose page @@ -446,26 +418,19 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, */ cond_resched(); continue; - } - if (err) { /* swp entry is obsolete ? */ - radix_tree_preload_end(); + } else if (err) /* swp entry is obsolete ? */ break; - } - /* May fail (-ENOMEM) if radix-tree node allocation failed. */ + /* May fail (-ENOMEM) if XArray node allocation failed. */ __SetPageLocked(new_page); __SetPageSwapBacked(new_page); - err = __add_to_swap_cache(new_page, entry); + err = add_to_swap_cache(new_page, entry, gfp_mask & GFP_KERNEL); if (likely(!err)) { - radix_tree_preload_end(); - /* - * Initiate read into locked page and return. - */ + /* Initiate read into locked page */ lru_cache_add_anon(new_page); *new_page_allocated = true; return new_page; } - radix_tree_preload_end(); __ClearPageLocked(new_page); /* * add_to_swap_cache() doesn't return -EEXIST, so we can safely -- 2.16.2 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot