From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id 1E75D6B03A1 for ; Fri, 14 Apr 2017 10:08:07 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id m66so50454202pga.15 for ; Fri, 14 Apr 2017 07:08:07 -0700 (PDT) Received: from EUR03-VE1-obe.outbound.protection.outlook.com (mail-eopbgr50113.outbound.protection.outlook.com. [40.107.5.113]) by mx.google.com with ESMTPS id 5si2153452plx.87.2017.04.14.07.08.06 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Fri, 14 Apr 2017 07:08:06 -0700 (PDT) From: Andrey Ryabinin Subject: [PATCH 3/4] mm/truncate: bail out early from invalidate_inode_pages2_range() if mapping is empty Date: Fri, 14 Apr 2017 17:07:52 +0300 Message-ID: <20170414140753.16108-4-aryabinin@virtuozzo.com> In-Reply-To: <20170414140753.16108-1-aryabinin@virtuozzo.com> References: <20170414140753.16108-1-aryabinin@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: Alexander Viro , linux-fsdevel@vger.kernel.org Cc: Andrey Ryabinin , Konrad Rzeszutek Wilk , Eric Van Hensbergen , Ron Minnich , Latchesar Ionkov , Steve French , Matthew Wilcox , Ross Zwisler , Trond Myklebust , Anna Schumaker , Andrew Morton , Jan Kara , Jens Axboe , Johannes Weiner , Alexey Kuznetsov , Christoph Hellwig , v9fs-developer@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-nfs@vger.kernel.org, linux-mm@kvack.org If mapping is empty (both ->nrpages and ->nrexceptional is zero) we can avoid pointless lookups in empty radix tree and bail out immediately after cleancache invalidation. Signed-off-by: Andrey Ryabinin --- mm/truncate.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/truncate.c b/mm/truncate.c index 6263aff..8f12b0e 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -624,6 +624,9 @@ int invalidate_inode_pages2_range(struct address_space *mapping, int did_range_unmap = 0; cleancache_invalidate_inode(mapping); + if (mapping->nrpages == 0 && mapping->nrexceptional == 0) + return 0; + pagevec_init(&pvec, 0); index = start; while (index <= end && pagevec_lookup_entries(&pvec, mapping, index, -- 2.10.2 -- 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