From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with SMTP id 6A6B86B00B2 for ; Thu, 4 Nov 2010 16:28:25 -0400 (EDT) Date: Thu, 4 Nov 2010 21:17:27 +0100 (CET) From: Jesper Juhl Subject: [PATCH v2] cgroup: prefer [kv]zalloc[_node] over [kv]malloc+memset in memory controller code. Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, Balbir Singh , Pavel Emelianov , Minchan Kim , Paul Menage , Li Zefan , Johannes Weiner , Wu Fengguang , containers@lists.linux-foundation.org, Andrew Morton List-ID: Hi, In mem_cgroup_alloc() we currently do either kmalloc() or vmalloc() then followed by memset() to zero the memory. This can be more efficiently achieved by using kzalloc() and vzalloc(). There's also one situation where we can use kzalloc_node() - this is what's new in this version of the patch. The original patch was: Acked-by: KAMEZAWA Hiroyuki Reviewed-by: Minchan Kim Reviewed-by: Wu Fengguang Acked-by: Balbir Singh Here's version 2. I'd appreciate it if someone could merge it, but I don't know who that someone would be. Signed-off-by: Jesper Juhl --- memcontrol.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9a99cfa..4f4e676 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4169,13 +4169,11 @@ static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) */ if (!node_state(node, N_NORMAL_MEMORY)) tmp = -1; - pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, tmp); + pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, tmp); if (!pn) return 1; mem->info.nodeinfo[node] = pn; - memset(pn, 0, sizeof(*pn)); - for (zone = 0; zone < MAX_NR_ZONES; zone++) { mz = &pn->zoneinfo[zone]; for_each_lru(l) @@ -4199,14 +4197,13 @@ static struct mem_cgroup *mem_cgroup_alloc(void) /* Can be very big if MAX_NUMNODES is very big */ if (size < PAGE_SIZE) - mem = kmalloc(size, GFP_KERNEL); + mem = kzalloc(size, GFP_KERNEL); else - mem = vmalloc(size); + mem = vzalloc(size); if (!mem) return NULL; - memset(mem, 0, size); mem->stat = alloc_percpu(struct mem_cgroup_stat_cpu); if (!mem->stat) { if (size < PAGE_SIZE) -- Jesper Juhl http://www.chaosbits.net/ Plain text mails only, please http://www.expita.com/nomime.html Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html -- 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 policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org