From: yuzhoujian Date: Fri, 28 Dec 2018 08:36:10 +0000 (-0800) Subject: mm, oom: add oom victim's memcg to the oom context information X-Git-Tag: 4.21-smb3-small-fixes~60^2~62 X-Git-Url: http://git.samba.org/samba.git/?p=sfrench%2Fcifs-2.6.git;a=commitdiff_plain;h=f0c867d9588d9efc10d6a55009c9560336673369 mm, oom: add oom victim's memcg to the oom context information The current oom report doesn't display victim's memcg context during the global OOM situation. While this information is not strictly needed, it can be really helpful for containerized environments to locate which container has lost a process. Now that we have a single line for the oom context, we can trivially add both the oom memcg (this can be either global_oom or a specific memcg which hits its hard limits) and task_memcg which is the victim's memcg. Below is the single line output in the oom report after this patch. - global oom context information: oom-kill:constraint=,nodemask=,cpuset=,mems_allowed=,global_oom,task_memcg=,task=,pid=,uid= - memcg oom context information: oom-kill:constraint=,nodemask=,cpuset=,mems_allowed=,oom_memcg=,task_memcg=,task=,pid=,uid= [penguin-kernel@I-love.SAKURA.ne.jp: use pr_cont() in mem_cgroup_print_oom_context()] Link: http://lkml.kernel.org/r/201812190723.wBJ7NdkN032628@www262.sakura.ne.jp Link: http://lkml.kernel.org/r/1542799799-36184-2-git-send-email-ufo19890607@gmail.com Signed-off-by: yuzhoujian Signed-off-by: Tetsuo Handa Acked-by: Michal Hocko Cc: David Rientjes Cc: "Kirill A . Shutemov" Cc: Andrea Arcangeli Cc: Tetsuo Handa Cc: Roman Gushchin Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 7ab2120155a4..83ae11cbd12c 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -526,9 +526,11 @@ void mem_cgroup_handle_over_high(void); unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg); -void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, +void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p); +void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg); + static inline void mem_cgroup_enter_user_fault(void) { WARN_ON(current->in_user_fault); @@ -970,7 +972,12 @@ static inline unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg) } static inline void -mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) +mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p) +{ +} + +static inline void +mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg) { } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 6e1469b80cb7..4afd5971f2d4 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1293,32 +1293,39 @@ static const char *const memcg1_stat_names[] = { #define K(x) ((x) << (PAGE_SHIFT-10)) /** - * mem_cgroup_print_oom_info: Print OOM information relevant to memory controller. + * mem_cgroup_print_oom_context: Print OOM information relevant to + * memory controller. * @memcg: The memory cgroup that went over limit * @p: Task that is going to be killed * * NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is * enabled */ -void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) +void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p) { - struct mem_cgroup *iter; - unsigned int i; - rcu_read_lock(); + if (memcg) { + pr_cont(",oom_memcg="); + pr_cont_cgroup_path(memcg->css.cgroup); + } else + pr_cont(",global_oom"); if (p) { - pr_info("Task in "); + pr_cont(",task_memcg="); pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id)); - pr_cont(" killed as a result of limit of "); - } else { - pr_info("Memory limit reached of cgroup "); } - - pr_cont_cgroup_path(memcg->css.cgroup); - pr_cont("\n"); - rcu_read_unlock(); +} + +/** + * mem_cgroup_print_oom_meminfo: Print OOM memory information relevant to + * memory controller. + * @memcg: The memory cgroup that went over limit + */ +void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg) +{ + struct mem_cgroup *iter; + unsigned int i; pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n", K((u64)page_counter_read(&memcg->memory)), diff --git a/mm/oom_kill.c b/mm/oom_kill.c index d90253f1ff93..5442cb12e4ed 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -435,6 +435,7 @@ static void dump_oom_summary(struct oom_control *oc, struct task_struct *victim) oom_constraint_text[oc->constraint], nodemask_pr_args(oc->nodemask)); cpuset_print_current_mems_allowed(); + mem_cgroup_print_oom_context(oc->memcg, victim); pr_cont(",task=%s,pid=%d,uid=%d\n", victim->comm, victim->pid, from_kuid(&init_user_ns, task_uid(victim))); } @@ -449,7 +450,7 @@ static void dump_header(struct oom_control *oc, struct task_struct *p) dump_stack(); if (is_memcg_oom(oc)) - mem_cgroup_print_oom_info(oc->memcg, p); + mem_cgroup_print_oom_meminfo(oc->memcg); else { show_mem(SHOW_MEM_FILTER_NODES, oc->nodemask); if (is_dump_unreclaim_slabs())