From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: [PATCH v10 41/62] shmem: Convert shmem_free_swap to XArray Date: Thu, 29 Mar 2018 20:42:24 -0700 Message-ID: <20180330034245.10462-42-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: Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-4.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1f1kwe-0004PE-Bs for linux-f2fs-devel@lists.sourceforge.net; Fri, 30 Mar 2018 03:43:16 +0000 Received: from bombadil.infradead.org ([198.137.202.133]) by sfi-mx-1.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) id 1f1kwc-00FCz1-W9 for linux-f2fs-devel@lists.sourceforge.net; Fri, 30 Mar 2018 03:43:16 +0000 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 This is a perfect use for xa_cmpxchg(). Note the use of 0 for GFP flags; we won't be allocating memory. Signed-off-by: Matthew Wilcox --- mm/shmem.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index aa7e92b24c19..be8c6d43b4aa 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -644,16 +644,13 @@ static void shmem_delete_from_page_cache(struct page *page, void *radswap) } /* - * Remove swap entry from radix tree, free the swap and its page cache. + * Remove swap entry from page cache, free the swap and its page cache. */ static int shmem_free_swap(struct address_space *mapping, pgoff_t index, void *radswap) { - void *old; + void *old = xa_cmpxchg(&mapping->i_pages, index, radswap, NULL, 0); - xa_lock_irq(&mapping->i_pages); - old = radix_tree_delete_item(&mapping->i_pages, index, radswap); - xa_unlock_irq(&mapping->i_pages); if (old != radswap) return -ENOENT; free_swap_and_cache(radix_to_swp_entry(radswap)); -- 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