diff options
Diffstat (limited to 'drivers/staging/android/lowmemorykiller.c')
-rw-r--r-- | drivers/staging/android/lowmemorykiller.c | 91 |
1 files changed, 46 insertions, 45 deletions
diff --git a/drivers/staging/android/lowmemorykiller.c b/drivers/staging/android/lowmemorykiller.c index efc7dc1..052b43e 100644 --- a/drivers/staging/android/lowmemorykiller.c +++ b/drivers/staging/android/lowmemorykiller.c @@ -1,16 +1,17 @@ /* drivers/misc/lowmemorykiller.c * * The lowmemorykiller driver lets user-space specify a set of memory thresholds - * where processes with a range of oom_adj values will get killed. Specify the - * minimum oom_adj values in /sys/module/lowmemorykiller/parameters/adj and the - * number of free pages in /sys/module/lowmemorykiller/parameters/minfree. Both - * files take a comma separated list of numbers in ascending order. + * where processes with a range of oom_score_adj values will get killed. Specify + * the minimum oom_score_adj values in + * /sys/module/lowmemorykiller/parameters/adj and the number of free pages in + * /sys/module/lowmemorykiller/parameters/minfree. Both files take a comma + * separated list of numbers in ascending order. * * For example, write "0,8" to /sys/module/lowmemorykiller/parameters/adj and * "1024,4096" to /sys/module/lowmemorykiller/parameters/minfree to kill - * processes with a oom_adj value of 8 or higher when the free memory drops - * below 4096 pages and kill processes with a oom_adj value of 0 or higher - * when the free memory drops below 1024 pages. + * processes with a oom_score_adj value of 8 or higher when the free memory + * drops below 4096 pages and kill processes with a oom_score_adj value of 0 or + * higher when the free memory drops below 1024 pages. * * The driver considers memory used for caches to be free, but if a large * percentage of the cached memory is locked this can be very inaccurate @@ -34,6 +35,7 @@ #include <linux/mm.h> #include <linux/oom.h> #include <linux/sched.h> +#include <linux/rcupdate.h> #include <linux/profile.h> #include <linux/notifier.h> @@ -45,7 +47,7 @@ static int lowmem_adj[6] = { 12, }; static int lowmem_adj_size = 4; -static size_t lowmem_minfree[6] = { +static int lowmem_minfree[6] = { 3 * 512, /* 6MB */ 2 * 1024, /* 8MB */ 4 * 1024, /* 16MB */ @@ -73,23 +75,23 @@ static int task_notify_func(struct notifier_block *self, unsigned long val, void *data) { struct task_struct *task = data; - if (task == lowmem_deathpending) { + + if (task == lowmem_deathpending) lowmem_deathpending = NULL; - task_handoff_unregister(&task_nb); - } + return NOTIFY_OK; } static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc) { - struct task_struct *p; + struct task_struct *tsk; struct task_struct *selected = NULL; int rem = 0; int tasksize; int i; - int min_adj = OOM_ADJUST_MAX + 1; + int min_score_adj = OOM_SCORE_ADJ_MAX + 1; int selected_tasksize = 0; - int selected_oom_adj; + int selected_oom_score_adj; int array_size = ARRAY_SIZE(lowmem_adj); int other_free = global_page_state(NR_FREE_PAGES); int other_file = global_page_state(NR_FILE_PAGES) - @@ -115,80 +117,77 @@ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc) for (i = 0; i < array_size; i++) { if (other_free < lowmem_minfree[i] && other_file < lowmem_minfree[i]) { - min_adj = lowmem_adj[i]; + min_score_adj = lowmem_adj[i]; break; } } if (sc->nr_to_scan > 0) lowmem_print(3, "lowmem_shrink %lu, %x, ofree %d %d, ma %d\n", sc->nr_to_scan, sc->gfp_mask, other_free, - other_file, min_adj); + other_file, min_score_adj); rem = global_page_state(NR_ACTIVE_ANON) + global_page_state(NR_ACTIVE_FILE) + global_page_state(NR_INACTIVE_ANON) + global_page_state(NR_INACTIVE_FILE); - if (sc->nr_to_scan <= 0 || min_adj == OOM_ADJUST_MAX + 1) { + if (sc->nr_to_scan <= 0 || min_score_adj == OOM_SCORE_ADJ_MAX + 1) { lowmem_print(5, "lowmem_shrink %lu, %x, return %d\n", sc->nr_to_scan, sc->gfp_mask, rem); return rem; } - selected_oom_adj = min_adj; - - read_lock(&tasklist_lock); - for_each_process(p) { - struct mm_struct *mm; - struct signal_struct *sig; - int oom_adj; - - task_lock(p); - mm = p->mm; - sig = p->signal; - if (!mm || !sig) { - task_unlock(p); + selected_oom_score_adj = min_score_adj; + + rcu_read_lock(); + for_each_process(tsk) { + struct task_struct *p; + int oom_score_adj; + + if (tsk->flags & PF_KTHREAD) continue; - } - oom_adj = sig->oom_adj; - if (oom_adj < min_adj) { + + p = find_lock_task_mm(tsk); + if (!p) + continue; + + oom_score_adj = p->signal->oom_score_adj; + if (oom_score_adj < min_score_adj) { task_unlock(p); continue; } - tasksize = get_mm_rss(mm); + tasksize = get_mm_rss(p->mm); task_unlock(p); if (tasksize <= 0) continue; if (selected) { - if (oom_adj < selected_oom_adj) + if (oom_score_adj < selected_oom_score_adj) continue; - if (oom_adj == selected_oom_adj && + if (oom_score_adj == selected_oom_score_adj && tasksize <= selected_tasksize) continue; } selected = p; selected_tasksize = tasksize; - selected_oom_adj = oom_adj; + selected_oom_score_adj = oom_score_adj; lowmem_print(2, "select %d (%s), adj %d, size %d, to kill\n", - p->pid, p->comm, oom_adj, tasksize); + p->pid, p->comm, oom_score_adj, tasksize); } if (selected) { lowmem_print(1, "send sigkill to %d (%s), adj %d, size %d\n", selected->pid, selected->comm, - selected_oom_adj, selected_tasksize); + selected_oom_score_adj, selected_tasksize); /* - * If CONFIG_PROFILING is off, then task_handoff_register() - * is a nop. In that case we don't want to stall the killer - * by setting lowmem_deathpending. + * If CONFIG_PROFILING is off, then we don't want to stall + * the killer by setting lowmem_deathpending. */ #ifdef CONFIG_PROFILING lowmem_deathpending = selected; lowmem_deathpending_timeout = jiffies + HZ; - task_handoff_register(&task_nb); #endif - force_sig(SIGKILL, selected); + send_sig(SIGKILL, selected, 0); rem -= selected_tasksize; } lowmem_print(4, "lowmem_shrink %lu, %x, return %d\n", sc->nr_to_scan, sc->gfp_mask, rem); - read_unlock(&tasklist_lock); + rcu_read_unlock(); return rem; } @@ -199,6 +198,7 @@ static struct shrinker lowmem_shrinker = { static int __init lowmem_init(void) { + task_handoff_register(&task_nb); register_shrinker(&lowmem_shrinker); return 0; } @@ -206,6 +206,7 @@ static int __init lowmem_init(void) static void __exit lowmem_exit(void) { unregister_shrinker(&lowmem_shrinker); + task_handoff_unregister(&task_nb); } module_param_named(cost, lowmem_shrinker.seeks, int, S_IRUGO | S_IWUSR); |