From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f54.google.com (mail-wg0-f54.google.com [74.125.82.54]) by kanga.kvack.org (Postfix) with ESMTP id BB21C800CA for ; Fri, 7 Nov 2014 14:34:46 -0500 (EST) Received: by mail-wg0-f54.google.com with SMTP id n12so4507571wgh.13 for ; Fri, 07 Nov 2014 11:34:46 -0800 (PST) Received: from mx2.suse.de (cantor2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id cq10si4535443wib.98.2014.11.07.11.34.45 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 07 Nov 2014 11:34:45 -0800 (PST) Message-ID: <1415388857.12094.2.camel@linux-t7sj.site> Subject: [PATCH -next] mm/rmap: calculate page offset when needed From: Davidlohr Bueso Date: Fri, 07 Nov 2014 11:34:17 -0800 Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Davidlohr Bueso Call page_to_pgoff() to get the page offset once we are sure we actually need it, and any very obvious initial function checks have passed. Trivial micro-optimization, and potentially save some cycles. Signed-off-by: Davidlohr Bueso --- mm/rmap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/mm/rmap.c b/mm/rmap.c index a5e9cc6..e3354b2 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1633,7 +1633,7 @@ static struct anon_vma *rmap_walk_anon_lock(struct page *page, static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc) { struct anon_vma *anon_vma; - pgoff_t pgoff = page_to_pgoff(page); + pgoff_t pgoff; struct anon_vma_chain *avc; int ret = SWAP_AGAIN; @@ -1641,6 +1641,7 @@ static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc) if (!anon_vma) return ret; + pgoff = page_to_pgoff(page); anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, pgoff, pgoff) { struct vm_area_struct *vma = avc->vma; unsigned long address = vma_address(page, vma); @@ -1674,7 +1675,7 @@ static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc) static int rmap_walk_file(struct page *page, struct rmap_walk_control *rwc) { struct address_space *mapping = page->mapping; - pgoff_t pgoff = page_to_pgoff(page); + pgoff_t pgoff; struct vm_area_struct *vma; int ret = SWAP_AGAIN; @@ -1689,6 +1690,7 @@ static int rmap_walk_file(struct page *page, struct rmap_walk_control *rwc) if (!mapping) return ret; + pgoff = page_to_pgoff(page); i_mmap_lock_read(mapping); vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { unsigned long address = vma_address(page, vma); -- 1.8.4.5 -- 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