[PATCH 3/7] memcg: add GPU statistic

[Dave Airlie <airlied@gmail.com>]

From: Dave Airlie <airlied@redhat.com>

Discrete and Integrated GPUs can use system RAM instead of
VRAM for all or some allocations. These allocations happen
via drm/ttm subsystem and are currently not accounted for
in cgroups.

Add a gpu statistic to allow a place to visualise allocations
once they are supported.

Signed-off-by: Dave Airlie <airlied@redhat.com>
---
 Documentation/admin-guide/cgroup-v2.rst | 3 +++
 include/linux/memcontrol.h              | 1 +
 mm/memcontrol.c                         | 2 ++
 3 files changed, 6 insertions(+)

diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index 1a16ce68a4d7..e10a1dfa6051 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -1480,6 +1480,9 @@ The following nested keys are defined.
 	  vmalloc (npn)
 		Amount of memory used for vmap backed memory.
 
+	  gpu (npn)
+		Amount of memory used for GPU device system RAM.
+
 	  shmem
 		Amount of cached filesystem data that is swap-backed,
 		such as tmpfs, shm segments, shared anonymous mmap()s
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 53364526d877..4058d4bd94ed 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -36,6 +36,7 @@ enum memcg_stat_item {
 	MEMCG_SOCK,
 	MEMCG_PERCPU_B,
 	MEMCG_VMALLOC,
+	MEMCG_GPU,
 	MEMCG_KMEM,
 	MEMCG_ZSWAP_B,
 	MEMCG_ZSWAPPED,
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c96c1f2b9cf5..25471a0fd0be 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -326,6 +326,7 @@ static const unsigned int memcg_stat_items[] = {
 	MEMCG_SOCK,
 	MEMCG_PERCPU_B,
 	MEMCG_VMALLOC,
+	MEMCG_GPU,
 	MEMCG_KMEM,
 	MEMCG_ZSWAP_B,
 	MEMCG_ZSWAPPED,
@@ -1358,6 +1359,7 @@ static const struct memory_stat memory_stats[] = {
 	{ "percpu",			MEMCG_PERCPU_B			},
 	{ "sock",			MEMCG_SOCK			},
 	{ "vmalloc",			MEMCG_VMALLOC			},
+	{ "gpu",			MEMCG_GPU			},
 	{ "shmem",			NR_SHMEM			},
 #ifdef CONFIG_ZSWAP
 	{ "zswap",			MEMCG_ZSWAP_B			},
-- 
2.49.0