From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx136.postini.com [74.125.245.136]) by kanga.kvack.org (Postfix) with SMTP id 9FE026B0069 for ; Tue, 5 Jun 2012 02:34:27 -0400 (EDT) Received: by lbjn8 with SMTP id n8so4936055lbj.14 for ; Mon, 04 Jun 2012 23:34:25 -0700 (PDT) MIME-Version: 1.0 Date: Tue, 5 Jun 2012 14:34:25 +0800 Message-ID: Subject: [PATCH] vmalloc: walk vmap_areas by sorted list instead of rb_next() From: Hong zhi guo Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, zhiguo.hong@nsn.com There's a walk by repeating rb_next to find a suitable hole. Could be simply replaced by walk on the sorted vmap_area_list. More simpler and efficient. Mutation of the list and tree only happens in pair within __insert_vmap_area and __free_vmap_area, under protection of vmap_area_lock. The patch code is also under vmap_area_lock, so the list walk is safe, and consistent with the tree walk. Tested on SMP by repeating batch of vmalloc anf vfree for random sizes and rounds for hours. Signed-off-by: Hong Zhiguo --- mm/vmalloc.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 2aad499..0eb5347 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -413,11 +413,11 @@ nocache: if (addr + size - 1 < addr) goto overflow; - n = rb_next(&first->rb_node); - if (n) - first = rb_entry(n, struct vmap_area, rb_node); - else + if (list_is_last(&first->list, &vmap_area_list)) goto found; + + first = list_entry(first->list.next, + struct vmap_area, list); } found: -- 1.7.4.1 -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org