From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id 003986B026E for ; Tue, 13 Mar 2018 09:27:07 -0400 (EDT) Received: by mail-pf0-f199.google.com with SMTP id h11so7457501pfn.0 for ; Tue, 13 Mar 2018 06:27:06 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org. [2607:7c80:54:e::133]) by mx.google.com with ESMTPS id p75si146224pfi.293.2018.03.13.06.27.05 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 13 Mar 2018 06:27:05 -0700 (PDT) From: Matthew Wilcox Subject: [PATCH v9 48/61] shmem: Convert shmem_free_swap to XArray Date: Tue, 13 Mar 2018 06:26:26 -0700 Message-Id: <20180313132639.17387-49-willy@infradead.org> In-Reply-To: <20180313132639.17387-1-willy@infradead.org> References: <20180313132639.17387-1-willy@infradead.org> Sender: owner-linux-mm@kvack.org List-ID: 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 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 a0a354a87f3b..cfbffb4b47a2 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -635,16 +635,13 @@ 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)); -- 2.16.1