diff options
| -rw-r--r-- | mm/oom_kill.c | 34 |
1 files changed, 31 insertions, 3 deletions
diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 942861bf9177..31bd0c344fa7 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -82,6 +82,24 @@ static bool has_intersects_mems_allowed(struct task_struct *tsk, #endif /* CONFIG_NUMA */ /* + * If this is a system OOM (not a memcg OOM) and the task selected to be + * killed is not already running at high (RT) priorities, speed up the + * recovery by boosting the dying task to the lowest FIFO priority. + * That helps with the recovery and avoids interfering with RT tasks. + */ +static void boost_dying_task_prio(struct task_struct *p, + struct mem_cgroup *mem) +{ + struct sched_param param = { .sched_priority = 1 }; + + if (mem) + return; + + if (!rt_task(p)) + sched_setscheduler_nocheck(p, SCHED_FIFO, ¶m); +} + +/* * The process p may have detached its own ->mm while exiting or through * use_mm(), but one or more of its subthreads may still have a valid * pointer. Return p, or any of its subthreads with a valid ->mm, with @@ -421,7 +439,7 @@ static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order, } #define K(x) ((x) << (PAGE_SHIFT-10)) -static int oom_kill_task(struct task_struct *p) +static int oom_kill_task(struct task_struct *p, struct mem_cgroup *mem) { p = find_lock_task_mm(p); if (!p) { @@ -434,9 +452,17 @@ static int oom_kill_task(struct task_struct *p) K(get_mm_counter(p->mm, MM_FILEPAGES))); task_unlock(p); - p->rt.time_slice = HZ; + set_tsk_thread_flag(p, TIF_MEMDIE); force_sig(SIGKILL, p); + + /* + * We give our sacrificial lamb high priority and access to + * all the memory it needs. That way it should be able to + * exit() and clear out its resources quickly... + */ + boost_dying_task_prio(p, mem); + return 0; } #undef K @@ -460,6 +486,7 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, */ if (p->flags & PF_EXITING) { set_tsk_thread_flag(p, TIF_MEMDIE); + boost_dying_task_prio(p, mem); return 0; } @@ -489,7 +516,7 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, } } while_each_thread(p, t); - return oom_kill_task(victim); + return oom_kill_task(victim, mem); } /* @@ -670,6 +697,7 @@ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, */ if (fatal_signal_pending(current)) { set_thread_flag(TIF_MEMDIE); + boost_dying_task_prio(current, NULL); return; } |