diff options
Diffstat (limited to 'mm/oom_kill.c')
| -rw-r--r-- | mm/oom_kill.c | 74 |
1 files changed, 43 insertions, 31 deletions
diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 0a6e466..9a686aa 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -52,6 +52,20 @@ static int has_intersects_mems_allowed(struct task_struct *tsk) return 0; } +static struct task_struct *find_lock_task_mm(struct task_struct *p) +{ + struct task_struct *t = p; + + do { + task_lock(t); + if (likely(t->mm)) + return t; + task_unlock(t); + } while_each_thread(p, t); + + return NULL; +} + /** * badness - calculate a numeric value for how bad this task has been * @p: task struct of which task we should calculate @@ -74,8 +88,8 @@ static int has_intersects_mems_allowed(struct task_struct *tsk) unsigned long badness(struct task_struct *p, unsigned long uptime) { unsigned long points, cpu_time, run_time; - struct mm_struct *mm; struct task_struct *child; + struct task_struct *c, *t; int oom_adj = p->signal->oom_adj; struct task_cputime task_time; unsigned long utime; @@ -84,17 +98,14 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) if (oom_adj == OOM_DISABLE) return 0; - task_lock(p); - mm = p->mm; - if (!mm) { - task_unlock(p); + p = find_lock_task_mm(p); + if (!p) return 0; - } /* * The memory size of the process is the basis for the badness. */ - points = mm->total_vm; + points = p->mm->total_vm; /* * After this unlock we can no longer dereference local variable `mm' @@ -115,12 +126,17 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) * child is eating the vast majority of memory, adding only half * to the parents will make the child our kill candidate of choice. */ - list_for_each_entry(child, &p->children, sibling) { - task_lock(child); - if (child->mm != mm && child->mm) - points += child->mm->total_vm/2 + 1; - task_unlock(child); - } + t = p; + do { + list_for_each_entry(c, &t->children, sibling) { + child = find_lock_task_mm(c); + if (child) { + if (child->mm != p->mm) + points += child->mm->total_vm/2 + 1; + task_unlock(child); + } + } + } while_each_thread(p, t); /* * CPU time is in tens of seconds and run time is in thousands @@ -256,9 +272,6 @@ static struct task_struct *select_bad_process(unsigned long *ppoints, for_each_process(p) { unsigned long points; - /* skip tasks that have already released their mm */ - if (!p->mm) - continue; /* skip the init task and kthreads */ if (is_global_init(p) || (p->flags & PF_KTHREAD)) continue; @@ -385,14 +398,9 @@ static void __oom_kill_task(struct task_struct *p, int verbose) return; } - task_lock(p); - if (!p->mm) { - WARN_ON(1); - printk(KERN_WARNING "tried to kill an mm-less task %d (%s)!\n", - task_pid_nr(p), p->comm); - task_unlock(p); + p = find_lock_task_mm(p); + if (!p) return; - } if (verbose) printk(KERN_ERR "Killed process %d (%s) " @@ -437,6 +445,7 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, const char *message) { struct task_struct *c; + struct task_struct *t = p; if (printk_ratelimit()) dump_header(p, gfp_mask, order, mem); @@ -454,14 +463,17 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, message, task_pid_nr(p), p->comm, points); /* Try to kill a child first */ - list_for_each_entry(c, &p->children, sibling) { - if (c->mm == p->mm) - continue; - if (mem && !task_in_mem_cgroup(c, mem)) - continue; - if (!oom_kill_task(c)) - return 0; - } + do { + list_for_each_entry(c, &t->children, sibling) { + if (c->mm == p->mm) + continue; + if (mem && !task_in_mem_cgroup(c, mem)) + continue; + if (!oom_kill_task(c)) + return 0; + } + } while_each_thread(p, t); + return oom_kill_task(p); } |