diff options
author | Tejun Heo <tj@kernel.org> | 2012-04-01 19:09:55 (GMT) |
---|---|---|
committer | Tejun Heo <tj@kernel.org> | 2012-04-01 19:09:55 (GMT) |
commit | af36f906c0f4c2ffa0482ecdf856a33dc88ae8c5 (patch) | |
tree | bbeb3d558e52dc064c74f028907b5b525f88cd14 /mm | |
parent | 4baf6e33251b37f111e21289f8ee71fe4cce236e (diff) | |
download | linux-fsl-qoriq-af36f906c0f4c2ffa0482ecdf856a33dc88ae8c5.tar.xz |
memcg: always create memsw files if CONFIG_CGROUP_MEM_RES_CTLR_SWAP
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 <tj@kernel.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/memcontrol.c | 65 |
1 files changed, 31 insertions, 34 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 7d698df..97a45b3 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3879,14 +3879,21 @@ 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) @@ -3903,7 +3910,9 @@ static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft) default: BUG(); } - 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... @@ -3919,6 +3928,10 @@ 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 */ @@ -3984,12 +3997,15 @@ 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) @@ -4655,7 +4671,7 @@ 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, }, @@ -4663,25 +4679,25 @@ 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", @@ -4721,14 +4737,11 @@ 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, }, @@ -4736,35 +4749,22 @@ 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) { @@ -5047,9 +5047,6 @@ 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; |