memcg: update menuconfig help text

	depends on CGROUPS && RESOURCE_COUNTERS

	select MM_OWNER

	help

	  Provides a memory resource controller that manages both page cache and

	  RSS memory.

	  Provides a memory resource controller that manages both anonymous

	  memory and page cache. (See Documentation/controllers/memory.txt)

	  Note that setting this option increases fixed memory overhead

	  associated with each page of memory in the system by 4/8 bytes

	  and also increases cache misses because struct page on many 64bit

	  systems will not fit into a single cache line anymore.

	  associated with each page of memory in the system. By this,

	  20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory

	  usage tracking struct at boot. Total amount of this is printed out

	  at boot.

	  Only enable when you're ok with these trade offs and really

	  sure you need the memory resource controller.

	  sure you need the memory resource controller. Even when you enable

	  this, you can set "cgroup_disable=memory" at your boot option to

	  disable memory resource controller and you can avoid overheads.

	  (and lose benefits of memory resource contoller)

	  This config option also selects MM_OWNER config option, which

	  could in turn add some fork/exit overhead.