memcg: do not check for do_swap_account in mem_cgroup_{read,write,reset}

Since 2d11085e ("memcg: do not create memsw files if swap accounting is
disabled") memsw files are created only if memcg swap accounting is
enabled so it doesn't make any sense to check for it explicitly in
mem_cgroup_read(), mem_cgroup_write() and mem_cgroup_reset().

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 2bdac3ececd09f85ac6c8046ba92d638faddf2aa..d280016039f29144655f346adcf4e9df5e0a7aec 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5025,9 +5025,6 @@ static ssize_t mem_cgroup_read(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 (type) {
        case _MEM:
                if (name == RES_USAGE)
@@ -5162,9 +5159,6 @@ 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 */
@@ -5241,9 +5235,6 @@ static int mem_cgroup_reset(struct cgroup *cont, unsigned int event)
        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)