From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: [PATCH v6 32/99] mm: Convert truncate to XArray Date: Wed, 17 Jan 2018 12:20:56 -0800 Message-ID: <20180117202203.19756-33-willy@infradead.org> References: <20180117202203.19756-1-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=z2wUjX53zsGmPoUiEiA7zW7Pqnae/hfF/ikw47JMqAo=; b=D+ZLr8vBjQEG3R8Wzczs4DPPYo q+QA7qBAIwAWOe9/Q1LCsC/Ve4IB656GUvzliAr2T/1O9954OqDU8FUQ/eqmvz5N0tYwuZRkUgHng f8unuxSVPtBFT+DmeBnf3+IfQwSG0Cku8of8aqzB4VJ7iybSjhbX9SQfV5LK91ouQTqw=; 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=z2wUjX53zsGmPoUiEiA7zW7Pqnae/hfF/ikw47JMqAo=; b=XNy5y1QFIVfRz782gjzXf1ksVx 7kSOI/qBG+0B61WnnKhLAaaSrjUMAGp5FznDdZnKZlW/kDavrWQSM+uZU0wi3Z9v5Sxo7up6G8XoY hrbD812rO/49zPdlX7potu6yqQMNDJSgp0uLmSQJiTlYWrKXyN8yDmeSsT638wevu0V4=; 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=z2wUjX53zsGmPoUiEiA7zW7Pqnae/hfF/ikw47JMqAo=; b=UVVbNfS46+4TSAeJMR4tkZdgE krd6cgrrD1lXZpmRTUAdmhCMqYiX5NGj7cNteCRp1Ui78W8Lfkq1/OnIgXX9nxY6wUphK66CWkscl bh0oTMgVheB0L38kjfA0rOMyf4aeWgGe8hlk6Xpn0tWx7Fx3D8Dbsi60BhuYgbRHe8lryJAemmu7z R1vs+bqmqrTDE1lL1RAXHGcXIm/pPaEEcCpDYn2QOE4cSMRAU1alZ8GN8WlMmoGXkV5SomzOL9Os4 ooqetvxaMiuGrfQFMks+D9AKJw5orOz5JvuGsPx715I2CxYVi9+oHzZ0hEcX527A7ARQhjIT/PoH/ aIM7o6ZhQ==; In-Reply-To: <20180117202203.19756-1-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-kernel@vger.kernel.org Cc: linux-s390@vger.kernel.org, David Howells , linux-nilfs@vger.kernel.org, Matthew Wilcox , linux-sh@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-usb@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-xfs@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Stefano Stabellini , linux-fsdevel@vger.kernel.org, cgroups@vger.kernel.org, Bjorn Andersson , linux-btrfs@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 69bb743dd7e5..70323c347298 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--; } @@ -746,10 +743,10 @@ 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)) { -- 2.15.1 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot