memcg: export struct mem_cgroup

mem_cgroup structure is defined in mm/memcontrol.c currently which means
that the code outside of this file has to use external API even for
trivial access stuff.

This patch exports mm_struct with its dependencies and makes some of the
exported functions inlines.  This even helps to reduce the code size a bit
(make defconfig + CONFIG_MEMCG=y)

  text		data    bss     dec     	 hex 	filename
  12355346        1823792 1089536 15268674         e8fb42 vmlinux.before
  12354970        1823792 1089536 15268298         e8f9ca vmlinux.after

This is not much (370B) but better than nothing.

We also save a function call in some hot paths like callers of
mem_cgroup_count_vm_event which is used for accounting.

The patch doesn't introduce any functional changes.

[vdavykov@parallels.com: inline memcg_kmem_is_active]
[vdavykov@parallels.com: do not expose type outside of CONFIG_MEMCG]
[akpm@linux-foundation.org: memcontrol.h needs eventfd.h for eventfd_ctx]
[akpm@linux-foundation.org: export mem_cgroup_from_task() to modules]
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Vladimir Davydov <vdavydov@parallels.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michal Hocko
2015-09-08 15:01:02 -07:00
committed by Linus Torvalds
parent b3d9ed3fd8
commit 33398cf2f3
7 changed files with 351 additions and 378 deletions

View File

@@ -1042,34 +1042,6 @@ struct proto {
#endif
};
/*
* Bits in struct cg_proto.flags
*/
enum cg_proto_flags {
/* Currently active and new sockets should be assigned to cgroups */
MEMCG_SOCK_ACTIVE,
/* It was ever activated; we must disarm static keys on destruction */
MEMCG_SOCK_ACTIVATED,
};
struct cg_proto {
struct page_counter memory_allocated; /* Current allocated memory. */
struct percpu_counter sockets_allocated; /* Current number of sockets. */
int memory_pressure;
long sysctl_mem[3];
unsigned long flags;
/*
* memcg field is used to find which memcg we belong directly
* Each memcg struct can hold more than one cg_proto, so container_of
* won't really cut.
*
* The elegant solution would be having an inverse function to
* proto_cgroup in struct proto, but that means polluting the structure
* for everybody, instead of just for memcg users.
*/
struct mem_cgroup *memcg;
};
int proto_register(struct proto *prot, int alloc_slab);
void proto_unregister(struct proto *prot);