[PATCH v1 5/9] mm: memcg: guard memcg1-specific fields accesses in mm/memcontrol.c

Roman Gushchin
2024-06-28T21:04:05Z

There are only few memcg1-specific struct mem_cgroup's members
accesses left in mm/memcontrol.c. Let's guard them with the
CONFIG_MEMCG_V1 config option.

Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
---
mm/memcontrol.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e78ed54d46d2..661e3a70e685 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3672,20 +3672,23 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
page_counter_set_high(&memcg->swap, PAGE_COUNTER_MAX);
if (parent) {
WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent));
- WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable));

page_counter_init(&memcg->memory, &parent->memory);
page_counter_init(&memcg->swap, &parent->swap);
+#ifdef CONFIG_MEMCG_V1
+ WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable));
page_counter_init(&memcg->kmem, &parent->kmem);
page_counter_init(&memcg->tcpmem, &parent->tcpmem);
+#endif
} else {
init_memcg_stats();
init_memcg_events();
page_counter_init(&memcg->memory, NULL);
page_counter_init(&memcg->swap, NULL);
+#ifdef CONFIG_MEMCG_V1
page_counter_init(&memcg->kmem, NULL);
page_counter_init(&memcg->tcpmem, NULL);
-
+#endif
root_mem_cgroup = memcg;
return &memcg->css;
}
@@ -3820,8 +3823,10 @@ static void mem_cgroup_css_reset(struct cgroup_subsys_state *css)

page_counter_set_max(&memcg->memory, PAGE_COUNTER_MAX);
page_counter_set_max(&memcg->swap, PAGE_COUNTER_MAX);
+#ifdef CONFIG_MEMCG_V1
page_counter_set_max(&memcg->kmem, PAGE_COUNTER_MAX);
page_counter_set_max(&memcg->tcpmem, PAGE_COUNTER_MAX);
+#endif
page_counter_set_min(&memcg->memory, 0);
page_counter_set_low(&memcg->memory, 0);
page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX);
--
2.45.2.803.g4e1b14247a-goog