Add cgroups_wait_empty proc file to show wait force empty memcgroup Add cgroup_empty_fail file to show memcgroup which had try many time still did not release. you can echo 0 > /proc/cgroup_empty_fail to manualy trigger force empty this memcgroup Signed-off-by: Xiongchun Duan <duanxiongchun@xxxxxxxxxxxxx> --- mm/memcontrol.c | 140 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 140 insertions(+) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 21b4432..1529549 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -57,6 +57,7 @@ #include <linux/sort.h> #include <linux/fs.h> #include <linux/seq_file.h> +#include <linux/proc_fs.h> #include <linux/vmpressure.h> #include <linux/mm_inline.h> #include <linux/swap_cgroup.h> @@ -6440,6 +6441,140 @@ void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) refill_stock(memcg, nr_pages); } +#ifdef CONFIG_PROC_FS +static void print_memcg_header(struct seq_file *m) +{ + seq_puts(m, "address,css_ref,mem_ref,current_retry,max_retry\n"); +} + +static void memcgroup_show(struct mem_cgroup *memcg, + struct seq_file *m, bool header) +{ + if (header) + print_memcg_header(m); + seq_printf(m, "%p,%lu,%lu,%d,%d\n", memcg, + atomic_long_read(&memcg->css.refcnt.count), + page_counter_read(&memcg->memory), + memcg->current_retry, memcg->max_retry); +} + +void *fail_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&offline_cgroup_mutex); + return seq_list_start(&empty_fail_list, *pos); +} + +void *fail_next(struct seq_file *m, void *p, loff_t *pos) +{ + return seq_list_next(p, &empty_fail_list, pos); +} + +void fail_stop(struct seq_file *m, void *p) +{ + mutex_unlock(&offline_cgroup_mutex); +} + +static int fail_show(struct seq_file *m, void *p) +{ + struct mem_cgroup *memcg = list_entry(p, struct mem_cgroup, + empty_fail_node); + if (p == empty_fail_list.next) + memcgroup_show(memcg, m, true); + else + memcgroup_show(memcg, m, false); + + return 0; +} + +static const struct seq_operations fail_list_op = { + .start = fail_start, + .next = fail_next, + .stop = fail_stop, + .show = fail_show, +}; + +static int fail_list_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &fail_list_op); +} + +ssize_t fail_list_write(struct file *file, const char __user *buffer, + size_t count, loff_t *ppos) +{ + struct list_head *pos, *n; + struct mem_cgroup *memcg; + + mutex_lock(&offline_cgroup_mutex); + list_for_each_safe(pos, n, &empty_fail_list) { + memcg = container_of(pos, struct mem_cgroup, empty_fail_node); + if (atomic_long_add_unless(&memcg->css.refcnt.count, + 1, 0) == 0) { + continue; + } else if (!queue_work(memcg_force_empty_wq, + &memcg->force_empty_work)) { + css_put(&memcg->css); + } + } + mutex_unlock(&offline_cgroup_mutex); + return count; +} + +static const struct file_operations proc_fail_list_operations = { + .open = fail_list_open, + .read = seq_read, + .write = fail_list_write, + .llseek = seq_lseek, + .release = seq_release, +}; + +void *empty_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&offline_cgroup_mutex); + return seq_list_start(&force_empty_list, *pos); +} + +void *empty_next(struct seq_file *m, void *p, loff_t *pos) +{ + return seq_list_next(p, &force_empty_list, pos); +} + +void empty_stop(struct seq_file *m, void *p) +{ + mutex_unlock(&offline_cgroup_mutex); +} + +static int empty_show(struct seq_file *m, void *p) +{ + struct mem_cgroup *memcg = list_entry(p, + struct mem_cgroup, force_empty_node); + if (p == force_empty_list.next) + memcgroup_show(memcg, m, true); + else + memcgroup_show(memcg, m, false); + + return 0; +} + +static const struct seq_operations empty_list_op = { + .start = empty_start, + .next = empty_next, + .stop = empty_stop, + .show = empty_show, +}; + +static int empty_list_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &empty_list_op); +} + +static const struct file_operations proc_empty_list_operations = { + .open = empty_list_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; +#endif + static int __init cgroup_memory(char *s) { char *token; @@ -6483,6 +6618,11 @@ static int __init mem_cgroup_init(void) INIT_WORK(&timer_poll_work, trigger_force_empty); timer_setup(&empty_trigger, empty_timer_trigger, 0); +#ifdef CONFIG_PROC_FS + proc_create("cgroups_wait_empty", 0, NULL, &proc_empty_list_operations); + proc_create("cgroups_empty_fail", 0, NULL, &proc_fail_list_operations); +#endif + cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL, memcg_hotplug_cpu_dead); -- 1.8.3.1