From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932281Ab2CUWU0 (ORCPT ); Wed, 21 Mar 2012 18:20:26 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:65325 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760267Ab2CUWSF (ORCPT ); Wed, 21 Mar 2012 18:18:05 -0400 From: Tejun Heo To: glommer@parallels.com, lizf@cn.fujitsu.com, containers@lists.linux-foundation.org, cgroups@vger.kernel.org Cc: linux-kernel@vger.kernel.org, fweisbec@gmail.com, rni@google.com, ctalbott@google.com, Tejun Heo , KAMEZAWA Hiroyuki Subject: [PATCH 07/12] memcg: always create memsw files if CONFIG_CGROUP_MEM_RES_CTLR_SWAP Date: Wed, 21 Mar 2012 15:17:40 -0700 Message-Id: <1332368265-21586-8-git-send-email-tj@kernel.org> X-Mailer: git-send-email 1.7.7.3 In-Reply-To: <1332368265-21586-1-git-send-email-tj@kernel.org> References: <1332368265-21586-1-git-send-email-tj@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Instead of conditioning creation of memsw files on do_swap_account, always create the files if compiled-in and fail read/write attempts with -EOPNOTSUPP if !do_swap_account. This is suggested by KAMEZAWA to simplify memcg file creation so that it can use cgroup->subsys_cftypes. Signed-off-by: Tejun Heo Cc: KAMEZAWA Hiroyuki --- mm/memcontrol.c | 65 ++++++++++++++++++++++++++---------------------------- 1 files changed, 31 insertions(+), 34 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index ae2f0a8..1e2a9d1 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3818,14 +3818,21 @@ static inline u64 mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) return val << PAGE_SHIFT; } -static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) +static ssize_t mem_cgroup_read(struct cgroup *cont, struct cftype *cft, + struct file *file, char __user *buf, + size_t nbytes, loff_t *ppos) { struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); + char str[64]; u64 val; - int type, name; + int type, name, len; type = MEMFILE_TYPE(cft->private); name = MEMFILE_ATTR(cft->private); + + if (!do_swap_account && type == _MEMSWAP) + return -EOPNOTSUPP; + switch (type) { case _MEM: if (name == RES_USAGE) @@ -3843,7 +3850,9 @@ static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) BUG(); break; } - return val; + + len = scnprintf(str, sizeof(str), "%llu\n", (unsigned long long)val); + return simple_read_from_buffer(buf, nbytes, ppos, str, len); } /* * The user of this function is... @@ -3859,6 +3868,10 @@ static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft, type = MEMFILE_TYPE(cft->private); name = MEMFILE_ATTR(cft->private); + + if (!do_swap_account && type == _MEMSWAP) + return -EOPNOTSUPP; + switch (name) { case RES_LIMIT: if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ @@ -3925,12 +3938,15 @@ out: static int mem_cgroup_reset(struct cgroup *cont, unsigned int event) { - struct mem_cgroup *memcg; + struct mem_cgroup *memcg = mem_cgroup_from_cont(cont); int type, name; - memcg = mem_cgroup_from_cont(cont); type = MEMFILE_TYPE(event); name = MEMFILE_ATTR(event); + + if (!do_swap_account && type == _MEMSWAP) + return -EOPNOTSUPP; + switch (name) { case RES_MAX_USAGE: if (type == _MEM) @@ -4599,7 +4615,7 @@ static struct cftype mem_cgroup_files[] = { { .name = "usage_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_USAGE), - .read_u64 = mem_cgroup_read, + .read = mem_cgroup_read, .register_event = mem_cgroup_usage_register_event, .unregister_event = mem_cgroup_usage_unregister_event, }, @@ -4607,25 +4623,25 @@ static struct cftype mem_cgroup_files[] = { .name = "max_usage_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE), .trigger = mem_cgroup_reset, - .read_u64 = mem_cgroup_read, + .read = mem_cgroup_read, }, { .name = "limit_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT), .write_string = mem_cgroup_write, - .read_u64 = mem_cgroup_read, + .read = mem_cgroup_read, }, { .name = "soft_limit_in_bytes", .private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT), .write_string = mem_cgroup_write, - .read_u64 = mem_cgroup_read, + .read = mem_cgroup_read, }, { .name = "failcnt", .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT), .trigger = mem_cgroup_reset, - .read_u64 = mem_cgroup_read, + .read = mem_cgroup_read, }, { .name = "stat", @@ -4665,14 +4681,11 @@ static struct cftype mem_cgroup_files[] = { .mode = S_IRUGO, }, #endif -}; - #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP -static struct cftype memsw_cgroup_files[] = { { .name = "memsw.usage_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE), - .read_u64 = mem_cgroup_read, + .read = mem_cgroup_read, .register_event = mem_cgroup_usage_register_event, .unregister_event = mem_cgroup_usage_unregister_event, }, @@ -4680,35 +4693,22 @@ static struct cftype memsw_cgroup_files[] = { .name = "memsw.max_usage_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE), .trigger = mem_cgroup_reset, - .read_u64 = mem_cgroup_read, + .read = mem_cgroup_read, }, { .name = "memsw.limit_in_bytes", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT), .write_string = mem_cgroup_write, - .read_u64 = mem_cgroup_read, + .read = mem_cgroup_read, }, { .name = "memsw.failcnt", .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT), .trigger = mem_cgroup_reset, - .read_u64 = mem_cgroup_read, + .read = mem_cgroup_read, }, -}; - -static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) -{ - if (!do_swap_account) - return 0; - return cgroup_add_files(cont, ss, memsw_cgroup_files, - ARRAY_SIZE(memsw_cgroup_files)); -}; -#else -static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss) -{ - return 0; -} #endif +}; static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *memcg, int node) { @@ -4969,9 +4969,6 @@ static int mem_cgroup_populate(struct cgroup_subsys *ss, ARRAY_SIZE(mem_cgroup_files)); if (!ret) - ret = register_memsw_files(cont, ss); - - if (!ret) ret = register_kmem_files(cont, ss); return ret; -- 1.7.7.3