diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 7bef427d5a82..6a5d65487b70 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -949,8 +949,12 @@ static inline void mod_memcg_page_state(struct page *page, rcu_read_unlock(); } +unsigned long memcg_events(struct mem_cgroup *memcg, int event); +unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap); unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx); unsigned long memcg_page_state_output(struct mem_cgroup *memcg, int item); +bool memcg_stat_item_valid(int idx); +bool memcg_vm_event_item_valid(enum vm_event_item idx); unsigned long lruvec_page_state(struct lruvec *lruvec, enum node_stat_item idx); unsigned long lruvec_page_state_local(struct lruvec *lruvec, enum node_stat_item idx); @@ -1379,6 +1383,16 @@ static inline unsigned long memcg_page_state_output(struct mem_cgroup *memcg, in return 0; } +static inline bool memcg_stat_item_valid(int idx) +{ + return false; +} + +static inline bool memcg_vm_event_item_valid(enum vm_event_item idx) +{ + return false; +} + static inline unsigned long lruvec_page_state(struct lruvec *lruvec, enum node_stat_item idx) { diff --git a/mm/bpf_memcontrol.c b/mm/bpf_memcontrol.c index 187919eb2fe2..e8fa7f5855f9 100644 --- a/mm/bpf_memcontrol.c +++ b/mm/bpf_memcontrol.c @@ -80,6 +80,85 @@ __bpf_kfunc void bpf_put_mem_cgroup(struct mem_cgroup *memcg) css_put(&memcg->css); } +/** + * bpf_mem_cgroup_vm_events - Read memory cgroup's vm event counter + * @memcg: memory cgroup + * @event: event id + * + * Allows to read memory cgroup event counters. + * + * Return: The current value of the corresponding events counter. + */ +__bpf_kfunc unsigned long bpf_mem_cgroup_vm_events(struct mem_cgroup *memcg, + enum vm_event_item event) +{ + if (unlikely(!memcg_vm_event_item_valid(event))) + return (unsigned long)-1; + + return memcg_events(memcg, event); +} + +/** + * bpf_mem_cgroup_usage - Read memory cgroup's usage + * @memcg: memory cgroup + * + * Please, note that the root memory cgroup it special and is exempt + * from the memory accounting. The returned value is a sum of sub-cgroup's + * usages and it not reflecting the size of the root memory cgroup itself. + * If you need to get an approximation, you can use root level statistics: + * e.g. NR_FILE_PAGES + NR_ANON_MAPPED. + * + * Return: The current memory cgroup size in bytes. + */ +__bpf_kfunc unsigned long bpf_mem_cgroup_usage(struct mem_cgroup *memcg) +{ + return page_counter_read(&memcg->memory) * PAGE_SIZE; +} + +/** + * bpf_mem_cgroup_memory_events - Read memory cgroup's memory event value + * @memcg: memory cgroup + * @event: memory event id + * + * Return: The current value of the memory event counter. + */ +__bpf_kfunc unsigned long bpf_mem_cgroup_memory_events(struct mem_cgroup *memcg, + enum memcg_memory_event event) +{ + if (unlikely(event >= MEMCG_NR_MEMORY_EVENTS)) + return (unsigned long)-1; + + return atomic_long_read(&memcg->memory_events[event]); +} + +/** + * bpf_mem_cgroup_page_state - Read memory cgroup's page state counter + * @memcg: memory cgroup + * @idx: counter idx + * + * Allows to read memory cgroup statistics. The output is in bytes. + * + * Return: The value of the page state counter in bytes. + */ +__bpf_kfunc unsigned long bpf_mem_cgroup_page_state(struct mem_cgroup *memcg, int idx) +{ + if (unlikely(!memcg_stat_item_valid(idx))) + return (unsigned long)-1; + + return memcg_page_state_output(memcg, idx); +} + +/** + * bpf_mem_cgroup_flush_stats - Flush memory cgroup's statistics + * @memcg: memory cgroup + * + * Propagate memory cgroup's statistics up the cgroup tree. + */ +__bpf_kfunc void bpf_mem_cgroup_flush_stats(struct mem_cgroup *memcg) +{ + mem_cgroup_flush_stats(memcg); +} + __bpf_kfunc_end_defs(); BTF_KFUNCS_START(bpf_memcontrol_kfuncs) @@ -87,6 +166,12 @@ BTF_ID_FLAGS(func, bpf_get_root_mem_cgroup, KF_ACQUIRE | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_get_mem_cgroup, KF_ACQUIRE | KF_RET_NULL | KF_RCU) BTF_ID_FLAGS(func, bpf_put_mem_cgroup, KF_RELEASE) +BTF_ID_FLAGS(func, bpf_mem_cgroup_vm_events, KF_TRUSTED_ARGS) +BTF_ID_FLAGS(func, bpf_mem_cgroup_memory_events, KF_TRUSTED_ARGS) +BTF_ID_FLAGS(func, bpf_mem_cgroup_usage, KF_TRUSTED_ARGS) +BTF_ID_FLAGS(func, bpf_mem_cgroup_page_state, KF_TRUSTED_ARGS) +BTF_ID_FLAGS(func, bpf_mem_cgroup_flush_stats, KF_TRUSTED_ARGS | KF_SLEEPABLE) + BTF_KFUNCS_END(bpf_memcontrol_kfuncs) static const struct btf_kfunc_id_set bpf_memcontrol_kfunc_set = { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index be810c1fbfc3..bae4eb72da61 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -663,6 +663,14 @@ unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx) return x; } +bool memcg_stat_item_valid(int idx) +{ + if ((u32)idx >= MEMCG_NR_STAT) + return false; + + return !BAD_STAT_IDX(memcg_stats_index(idx)); +} + static int memcg_page_state_unit(int item); /* @@ -860,6 +868,14 @@ unsigned long memcg_events(struct mem_cgroup *memcg, int event) return READ_ONCE(memcg->vmstats->events[i]); } +bool memcg_vm_event_item_valid(enum vm_event_item idx) +{ + if (idx >= NR_VM_EVENT_ITEMS) + return false; + + return !BAD_STAT_IDX(memcg_events_index(idx)); +} + #ifdef CONFIG_MEMCG_V1 unsigned long memcg_events_local(struct mem_cgroup *memcg, int event) {