[v5,6/6] mm: kmem: reimplement get_obj_cgroup_from_current()
Commit Message
Reimplement get_obj_cgroup_from_current() using current_obj_cgroup().
get_obj_cgroup_from_current() and current_obj_cgroup() share 80% of
the code, so the new implementation is almost trivial.
get_obj_cgroup_from_current() is a convenient function used by the
bpf subsystem, so there is no reason to get rid of it completely.
Signed-off-by: Roman Gushchin (Cruise) <roman.gushchin@linux.dev>
---
include/linux/memcontrol.h | 11 ++++++++++-
mm/memcontrol.c | 32 --------------------------------
2 files changed, 10 insertions(+), 33 deletions(-)
Comments
On 10/20/23 00:53, Roman Gushchin wrote:
> Reimplement get_obj_cgroup_from_current() using current_obj_cgroup().
> get_obj_cgroup_from_current() and current_obj_cgroup() share 80% of
> the code, so the new implementation is almost trivial.
Great.
> get_obj_cgroup_from_current() is a convenient function used by the
> bpf subsystem, so there is no reason to get rid of it completely.
>
> Signed-off-by: Roman Gushchin (Cruise) <roman.gushchin@linux.dev>
Reviwed-by: Vlastimil Babka <vbabka@suse.cz>
Thanks!
On Thu, Oct 19, 2023 at 3:54 PM Roman Gushchin <roman.gushchin@linux.dev> wrote:
>
> Reimplement get_obj_cgroup_from_current() using current_obj_cgroup().
> get_obj_cgroup_from_current() and current_obj_cgroup() share 80% of
> the code, so the new implementation is almost trivial.
>
> get_obj_cgroup_from_current() is a convenient function used by the
> bpf subsystem, so there is no reason to get rid of it completely.
>
> Signed-off-by: Roman Gushchin (Cruise) <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeelb@google.com>
@@ -1778,9 +1778,18 @@ void __memcg_kmem_uncharge_page(struct page *page, int order);
* needs to be used outside of the local scope.
*/
struct obj_cgroup *current_obj_cgroup(void);
-struct obj_cgroup *get_obj_cgroup_from_current(void);
struct obj_cgroup *get_obj_cgroup_from_folio(struct folio *folio);
+static inline struct obj_cgroup *get_obj_cgroup_from_current(void)
+{
+ struct obj_cgroup *objcg = current_obj_cgroup();
+
+ if (objcg)
+ obj_cgroup_get(objcg);
+
+ return objcg;
+}
+
int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size);
void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size);
@@ -3056,38 +3056,6 @@ static struct obj_cgroup *current_objcg_update(void)
return objcg;
}
-__always_inline struct obj_cgroup *get_obj_cgroup_from_current(void)
-{
- struct mem_cgroup *memcg;
- struct obj_cgroup *objcg;
-
- if (in_task()) {
- memcg = current->active_memcg;
- if (unlikely(memcg))
- goto from_memcg;
-
- objcg = READ_ONCE(current->objcg);
- if (unlikely((unsigned long)objcg & CURRENT_OBJCG_UPDATE_FLAG))
- objcg = current_objcg_update();
-
- if (objcg) {
- obj_cgroup_get(objcg);
- return objcg;
- }
- } else {
- memcg = this_cpu_read(int_active_memcg);
- if (unlikely(memcg))
- goto from_memcg;
- }
- return NULL;
-
-from_memcg:
- rcu_read_lock();
- objcg = __get_obj_cgroup_from_memcg(memcg);
- rcu_read_unlock();
- return objcg;
-}
-
__always_inline struct obj_cgroup *current_obj_cgroup(void)
{
struct mem_cgroup *memcg;