From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-f71.google.com (mail-pl0-f71.google.com [209.85.160.71]) by kanga.kvack.org (Postfix) with ESMTP id E14756B0295 for ; Mon, 19 Feb 2018 14:46:23 -0500 (EST) Received: by mail-pl0-f71.google.com with SMTP id a61so6661215pla.22 for ; Mon, 19 Feb 2018 11:46:23 -0800 (PST) Received: from bombadil.infradead.org (bombadil.infradead.org. [2607:7c80:54:e::133]) by mx.google.com with ESMTPS id w16-v6si4670832plp.276.2018.02.19.11.46.22 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 19 Feb 2018 11:46:22 -0800 (PST) From: Matthew Wilcox Subject: [PATCH v7 35/61] mm: Convert truncate to XArray Date: Mon, 19 Feb 2018 11:45:30 -0800 Message-Id: <20180219194556.6575-36-willy@infradead.org> In-Reply-To: <20180219194556.6575-1-willy@infradead.org> References: <20180219194556.6575-1-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 From: Matthew Wilcox This is essentially xa_cmpxchg() with the locking handled above us, and it doesn't have to handle replacing a NULL entry. Signed-off-by: Matthew Wilcox --- mm/truncate.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/mm/truncate.c b/mm/truncate.c index 3fe1e7461684..9267c1a12a31 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -33,15 +33,12 @@ static inline void __clear_shadow_entry(struct address_space *mapping, pgoff_t index, void *entry) { - struct radix_tree_node *node; - void **slot; + XA_STATE(xas, &mapping->pages, index); - if (!__radix_tree_lookup(&mapping->pages, index, &node, &slot)) + xas_set_update(&xas, workingset_update_node); + if (xas_load(&xas) != entry) return; - if (*slot != entry) - return; - __radix_tree_replace(&mapping->pages, node, slot, NULL, - workingset_update_node); + xas_store(&xas, NULL); mapping->nrexceptional--; } @@ -738,10 +735,10 @@ int invalidate_inode_pages2_range(struct address_space *mapping, index++; } /* - * For DAX we invalidate page tables after invalidating radix tree. We + * For DAX we invalidate page tables after invalidating page cache. We * could invalidate page tables while invalidating each entry however * that would be expensive. And doing range unmapping before doesn't - * work as we have no cheap way to find whether radix tree entry didn't + * work as we have no cheap way to find whether page cache entry didn't * get remapped later. */ if (dax_mapping(mapping)) { -- 2.16.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org