From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: [PATCH v8 29/63] page cache: Convert page deletion to XArray Date: Tue, 6 Mar 2018 11:23:39 -0800 Message-ID: <20180306192413.5499-30-willy@infradead.org> References: <20180306192413.5499-1-willy@infradead.org> Return-path: 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=AfhSPT6lIdBDimHGD4rCQ3/lGnIg9ct3nIy9Q9t+N4o=; b=nwTUcLJwJWlv5XmUQ3luDO29K aPDWuHKcDdvFpq3HRKUIZGA+XbRluTE21iMnZRSoMiSuaro5i5a4zimoneXRX1uG8PALN8/av1+dK asTItur2wbgIh8SN7J1AsHdjGMTfBqumf8vYz5kfZAHriQa/GUAy0Gi+ze+V6gnhSOTiltV/NP63A 7CRA33XsJF6yZjufkyb+XGOLqSntuvI0nSsQ67JfxWLpXlM5DZ7R8F8LuifoZPs/PInafTBKPn4bB 9LkNO6cUDOdrN4wzECrUQIkQ7i34TkuBK78xGvJ5mANQl3Y/PSR2RO0Upfyk9Ij7eiqRz+lkV68j2 In-Reply-To: <20180306192413.5499-1-willy@infradead.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Andrew Morton Cc: Matthew Wilcox , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Ryusuke Konishi , linux-nilfs@vger.kernel.org, linux-btrfs@vger.kernel.org From: Matthew Wilcox The code is slightly shorter and simpler. Signed-off-by: Matthew Wilcox --- mm/filemap.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 0e19ea454cba..bdda1beda932 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -111,30 +111,28 @@ * ->tasklist_lock (memory_failure, collect_procs_ao) */ -static void page_cache_tree_delete(struct address_space *mapping, +static void page_cache_delete(struct address_space *mapping, struct page *page, void *shadow) { - int i, nr; + XA_STATE(xas, &mapping->i_pages, page->index); + unsigned int i, nr; - /* hugetlb pages are represented by one entry in the radix tree */ + mapping_set_update(&xas, mapping); + + /* hugetlb pages are represented by a single entry in the xarray */ nr = PageHuge(page) ? 1 : hpage_nr_pages(page); VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageTail(page), page); VM_BUG_ON_PAGE(nr != 1 && shadow, page); - for (i = 0; i < nr; i++) { - struct radix_tree_node *node; - void **slot; - - __radix_tree_lookup(&mapping->i_pages, page->index + i, - &node, &slot); - - VM_BUG_ON_PAGE(!node && nr != 1, page); - - radix_tree_clear_tags(&mapping->i_pages, node, slot); - __radix_tree_replace(&mapping->i_pages, node, slot, shadow, - workingset_lookup_update(mapping)); + i = nr; +repeat: + xas_store(&xas, shadow); + xas_init_tags(&xas); + if (--i) { + xas_next(&xas); + goto repeat; } page->mapping = NULL; @@ -234,7 +232,7 @@ void __delete_from_page_cache(struct page *page, void *shadow) trace_mm_filemap_delete_from_page_cache(page); unaccount_page_cache_page(mapping, page); - page_cache_tree_delete(mapping, page, shadow); + page_cache_delete(mapping, page, shadow); } static void page_cache_free_page(struct address_space *mapping, -- 2.16.1