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 0BDD76B0279 for ; Mon, 17 Jul 2017 03:27:55 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id c14so19082665pgn.11 for ; Mon, 17 Jul 2017 00:27:55 -0700 (PDT) Received: from mail-pg0-x241.google.com (mail-pg0-x241.google.com. [2607:f8b0:400e:c05::241]) by mx.google.com with ESMTPS id x11si7969384pge.256.2017.07.17.00.27.53 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 17 Jul 2017 00:27:54 -0700 (PDT) Received: by mail-pg0-x241.google.com with SMTP id z1so3419839pgs.0 for ; Mon, 17 Jul 2017 00:27:53 -0700 (PDT) From: Zhaoyang Huang Subject: [PATCH v2] mm/vmalloc: terminate searching since one node found Date: Mon, 17 Jul 2017 15:27:31 +0800 Message-Id: <1500276451-10492-1-git-send-email-zhaoyang.huang@spreadtrum.com> Sender: owner-linux-mm@kvack.org List-ID: To: zhaoyang.huang@spreadtrum.com, Andrew Morton , Michal Hocko , Ingo Molnar , zijun_hu , Vlastimil Babka , Thomas Garnier , "Kirill A. Shutemov" , Andrey Ryabinin , linux-mm@kvack.org, linux-kernel@vger.kernel.org From: Zhaoyang Huang It is no need to find the very beginning of the area within alloc_vmap_area, which can be done by judging each node during the process For current approach, the worst case is that the starting node which be found for searching the 'vmap_area_list' is close to the 'vstart', while the final available one is round to the tail(especially for the left branch). This commit have the list searching start at the first available node, which will save the time of walking the rb tree'(1)' and walking the list(2). vmap_area_root / \ tmp_next U / (1) tmp / ... / first(current approach) vmap_area_list->...->first->...->tmp->tmp_next (2) Signed-off-by: Zhaoyang Huang --- mm/vmalloc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 34a1c3e..f833e07 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -459,9 +459,16 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, while (n) { struct vmap_area *tmp; + struct vmap_area *tmp_next; tmp = rb_entry(n, struct vmap_area, rb_node); + tmp_next = list_next_entry(tmp, list); if (tmp->va_end >= addr) { first = tmp; + if (ALIGN(tmp->va_end, align) + size + < tmp_next->va_start) { + addr = ALIGN(tmp->va_end, align); + goto found; + } if (tmp->va_start <= addr) break; n = n->rb_left; -- 1.9.1 -- 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