diff --git a/fs/proc/base.c b/fs/proc/base.c index d2d3108a611c..d7d711876b6a 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -411,12 +411,13 @@ static const struct file_operations proc_lstats_operations = { static int proc_oom_score(struct task_struct *task, char *buffer) { + unsigned long totalpages = totalram_pages + total_swap_pages; unsigned long points = 0; read_lock(&tasklist_lock); if (pid_alive(task)) - points = oom_badness(task, NULL, NULL, - totalram_pages + total_swap_pages); + points = oom_badness(task, NULL, NULL, totalpages) * + 1000 / totalpages; read_unlock(&tasklist_lock); return sprintf(buffer, "%lu\n", points); } diff --git a/include/linux/oom.h b/include/linux/oom.h index 3d7647536b03..e4c29bc72e70 100644 --- a/include/linux/oom.h +++ b/include/linux/oom.h @@ -43,8 +43,9 @@ enum oom_constraint { extern void compare_swap_oom_score_adj(int old_val, int new_val); extern int test_set_oom_score_adj(int new_val); -extern unsigned int oom_badness(struct task_struct *p, struct mem_cgroup *memcg, - const nodemask_t *nodemask, unsigned long totalpages); +extern unsigned long oom_badness(struct task_struct *p, + struct mem_cgroup *memcg, const nodemask_t *nodemask, + unsigned long totalpages); extern int try_set_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_flags); extern void clear_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_flags); diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 9f09a1fde9f9..ed0e19677360 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -180,10 +180,10 @@ static bool oom_unkillable_task(struct task_struct *p, * predictable as possible. The goal is to return the highest value for the * task consuming the most memory to avoid subsequent oom failures. */ -unsigned int oom_badness(struct task_struct *p, struct mem_cgroup *memcg, - const nodemask_t *nodemask, unsigned long totalpages) +unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg, + const nodemask_t *nodemask, unsigned long totalpages) { - long points; + unsigned long points; if (oom_unkillable_task(p, memcg, nodemask)) return 0; @@ -197,22 +197,12 @@ unsigned int oom_badness(struct task_struct *p, struct mem_cgroup *memcg, return 0; } - /* - * The memory controller may have a limit of 0 bytes, so avoid a divide - * by zero, if necessary. - */ - if (!totalpages) - totalpages = 1; - /* * The baseline for the badness score is the proportion of RAM that each * task's rss, pagetable and swap space use. */ - points = get_mm_rss(p->mm) + p->mm->nr_ptes; - points += get_mm_counter(p->mm, MM_SWAPENTS); - - points *= 1000; - points /= totalpages; + points = get_mm_rss(p->mm) + p->mm->nr_ptes + + get_mm_counter(p->mm, MM_SWAPENTS); task_unlock(p); /* @@ -220,23 +210,20 @@ unsigned int oom_badness(struct task_struct *p, struct mem_cgroup *memcg, * implementation used by LSMs. */ if (has_capability_noaudit(p, CAP_SYS_ADMIN)) - points -= 30; + points -= 30 * totalpages / 1000; /* * /proc/pid/oom_score_adj ranges from -1000 to +1000 such that it may * either completely disable oom killing or always prefer a certain * task. */ - points += p->signal->oom_score_adj; + points += p->signal->oom_score_adj * totalpages / 1000; /* - * Never return 0 for an eligible task that may be killed since it's - * possible that no single user task uses more than 0.1% of memory and - * no single admin tasks uses more than 3.0%. + * Never return 0 for an eligible task regardless of the root bonus and + * oom_score_adj (oom_score_adj can't be OOM_SCORE_ADJ_MIN here). */ - if (points <= 0) - return 1; - return (points < 1000) ? points : 1000; + return points ? points : 1; } /* @@ -314,7 +301,7 @@ static struct task_struct *select_bad_process(unsigned int *ppoints, { struct task_struct *g, *p; struct task_struct *chosen = NULL; - *ppoints = 0; + unsigned long chosen_points = 0; do_each_thread(g, p) { unsigned int points; @@ -354,7 +341,7 @@ static struct task_struct *select_bad_process(unsigned int *ppoints, */ if (p == current) { chosen = p; - *ppoints = 1000; + chosen_points = ULONG_MAX; } else if (!force_kill) { /* * If this task is not being ptraced on exit, @@ -367,12 +354,13 @@ static struct task_struct *select_bad_process(unsigned int *ppoints, } points = oom_badness(p, memcg, nodemask, totalpages); - if (points > *ppoints) { + if (points > chosen_points) { chosen = p; - *ppoints = points; + chosen_points = points; } } while_each_thread(g, p); + *ppoints = chosen_points * 1000 / totalpages; return chosen; } @@ -572,7 +560,7 @@ void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, } check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, order, NULL); - limit = mem_cgroup_get_limit(memcg) >> PAGE_SHIFT; + limit = mem_cgroup_get_limit(memcg) >> PAGE_SHIFT ? : 1; read_lock(&tasklist_lock); p = select_bad_process(&points, limit, memcg, NULL, false); if (p && PTR_ERR(p) != -1UL)