From: Vladimir Davydov Date: Thu, 9 Oct 2014 22:28:59 +0000 (-0700) Subject: memcg: zap memcg_can_account_kmem X-Git-Tag: fixes-against-v3.18-rc2~137^2~41 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cf2b8fbf1d2f7ba07999e97685563c94483d33d6;p=pandora-kernel.git memcg: zap memcg_can_account_kmem memcg_can_account_kmem() returns true iff !mem_cgroup_disabled() && !mem_cgroup_is_root(memcg) && memcg_kmem_is_active(memcg); To begin with the !mem_cgroup_is_root(memcg) check is useless, because one can't enable kmem accounting for the root cgroup (mem_cgroup_write() returns EINVAL on an attempt to set the limit on the root cgroup). Furthermore, the !mem_cgroup_disabled() check also seems to be redundant. The point is memcg_can_account_kmem() is called from three places: mem_cgroup_salbinfo_read(), __memcg_kmem_get_cache(), and __memcg_kmem_newpage_charge(). The latter two functions are only invoked if memcg_kmem_enabled() returns true, which implies that the memory cgroup subsystem is enabled. And mem_cgroup_slabinfo_read() shows the output of memory.kmem.slabinfo, which won't exist if the memory cgroup is completely disabled. So let's substitute all the calls to memcg_can_account_kmem() with plain memcg_kmem_is_active(), and kill the former. Signed-off-by: Vladimir Davydov Acked-by: Johannes Weiner Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed