diff options
| -rw-r--r-- | mm/oom_kill.c | 40 |
1 files changed, 25 insertions, 15 deletions
diff --git a/mm/oom_kill.c b/mm/oom_kill.c index d7f345e47e73..33b58615072c 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -31,6 +31,7 @@ #include <linux/memcontrol.h> #include <linux/mempolicy.h> #include <linux/security.h> +#include <linux/ptrace.h> int sysctl_panic_on_oom; int sysctl_oom_kill_allocating_task; @@ -316,22 +317,29 @@ static struct task_struct *select_bad_process(unsigned int *ppoints, if (test_tsk_thread_flag(p, TIF_MEMDIE)) return ERR_PTR(-1UL); - /* - * This is in the process of releasing memory so wait for it - * to finish before killing some other task by mistake. - * - * However, if p is the current task, we allow the 'kill' to - * go ahead if it is exiting: this will simply set TIF_MEMDIE, - * which will allow it to gain access to memory reserves in - * the process of exiting and releasing its resources. - * Otherwise we could get an easy OOM deadlock. - */ if (p->flags & PF_EXITING) { - if (p != current) - return ERR_PTR(-1UL); - - chosen = p; - *ppoints = 1000; + /* + * If p is the current task and is in the process of + * releasing memory, we allow the "kill" to set + * TIF_MEMDIE, which will allow it to gain access to + * memory reserves. Otherwise, it may stall forever. + * + * The loop isn't broken here, however, in case other + * threads are found to have already been oom killed. + */ + if (p == current) { + chosen = p; + *ppoints = 1000; + } else { + /* + * If this task is not being ptraced on exit, + * then wait for it to finish before killing + * some other task unnecessarily. + */ + if (!(task_ptrace(p->group_leader) & + PT_TRACE_EXIT)) + return ERR_PTR(-1UL); + } } points = oom_badness(p, mem, nodemask, totalpages); @@ -493,6 +501,8 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, list_for_each_entry(child, &t->children, sibling) { unsigned int child_points; + if (child->mm == p->mm) + continue; /* * oom_badness() returns 0 if the thread is unkillable */ |