1 files changed, 38 insertions, 46 deletions

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 92bcf1db16b2..175a67a78a99 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -58,6 +58,7 @@ 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;
+        int oom_adj;
 
         task_lock(p);
         mm = p->mm;
@@ -65,6 +66,11 @@ unsigned long badness(struct task_struct *p, unsigned long uptime)
                 task_unlock(p);
                 return 0;
         }
+        oom_adj = mm->oom_adj;
+        if (oom_adj == OOM_DISABLE) {
+                task_unlock(p);
+                return 0;
+        }
 
         /*
          * The memory size of the process is the basis for the badness.
@@ -148,15 +154,15 @@ unsigned long badness(struct task_struct *p, unsigned long uptime)
                 points /= 8;
 
         /*
-         * Adjust the score by oomkilladj.
+         * Adjust the score by oom_adj.
          */
-        if (p->oomkilladj) {
-                if (p->oomkilladj > 0) {
+        if (oom_adj) {
+                if (oom_adj > 0) {
                         if (!points)
                                 points = 1;
-                        points <<= p->oomkilladj;
+                        points <<= oom_adj;
                 } else
-                        points >>= -(p->oomkilladj);
+                        points >>= -(oom_adj);
         }
 
 #ifdef DEBUG
@@ -251,11 +257,8 @@ static struct task_struct *select_bad_process(unsigned long *ppoints,
                         *ppoints = ULONG_MAX;
                 }
 
-                if (p->oomkilladj == OOM_DISABLE)
-                        continue;
-
                 points = badness(p, uptime.tv_sec);
-                if (points > *ppoints || !chosen) {
+                if (points > *ppoints) {
                         chosen = p;
                         *ppoints = points;
                 }
@@ -284,22 +287,27 @@ static void dump_tasks(const struct mem_cgroup *mem)
         printk(KERN_INFO "[ pid ]   uid  tgid total_vm      rss cpu oom_adj "
                "name\n");
         do_each_thread(g, p) {
-                /*
-                 * total_vm and rss sizes do not exist for tasks with a
-                 * detached mm so there's no need to report them.
-                 */
-                if (!p->mm)
-                        continue;
+                struct mm_struct *mm;
+
                 if (mem && !task_in_mem_cgroup(p, mem))
                         continue;
                 if (!thread_group_leader(p))
                         continue;
 
                 task_lock(p);
+                mm = p->mm;
+                if (!mm) {
+                        /*
+                         * total_vm and rss sizes do not exist for tasks with no
+                         * mm so there's no need to report them; they can't be
+                         * oom killed anyway.
+                         */
+                        task_unlock(p);
+                        continue;
+                }
                 printk(KERN_INFO "[%5d] %5d %5d %8lu %8lu %3d     %3d %s\n",
-                       p->pid, __task_cred(p)->uid, p->tgid,
-                       p->mm->total_vm, get_mm_rss(p->mm), (int)task_cpu(p),
-                       p->oomkilladj, p->comm);
+                       p->pid, __task_cred(p)->uid, p->tgid, mm->total_vm,
+                       get_mm_rss(mm), (int)task_cpu(p), mm->oom_adj, p->comm);
                 task_unlock(p);
         } while_each_thread(g, p);
 }
@@ -317,11 +325,8 @@ static void __oom_kill_task(struct task_struct *p, int verbose)
                 return;
         }
 
-        if (!p->mm) {
-                WARN_ON(1);
-                printk(KERN_WARNING "tried to kill an mm-less task!\n");
+        if (!p->mm)
                 return;
-        }
 
         if (verbose)
                 printk(KERN_ERR "Killed process %d (%s)\n",
@@ -343,28 +348,13 @@ static int oom_kill_task(struct task_struct *p)
         struct mm_struct *mm;
         struct task_struct *g, *q;
 
+        task_lock(p);
         mm = p->mm;
-
-        /* WARNING: mm may not be dereferenced since we did not obtain its
-         * value from get_task_mm(p).  This is OK since all we need to do is
-         * compare mm to q->mm below.
-         *
-         * Furthermore, even if mm contains a non-NULL value, p->mm may
-         * change to NULL at any time since we do not hold task_lock(p).
-         * However, this is of no concern to us.
-         */
-
-        if (mm == NULL)
+        if (!mm || mm->oom_adj == OOM_DISABLE) {
+                task_unlock(p);
                 return 1;
-
-        /*
-         * Don't kill the process if any threads are set to OOM_DISABLE
-         */
-        do_each_thread(g, q) {
-                if (q->mm == mm && q->oomkilladj == OOM_DISABLE)
-                        return 1;
-        } while_each_thread(g, q);
-
+        }
+        task_unlock(p);
         __oom_kill_task(p, 1);
 
         /*
@@ -387,10 +377,11 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
         struct task_struct *c;
 
         if (printk_ratelimit()) {
-                printk(KERN_WARNING "%s invoked oom-killer: "
-                        "gfp_mask=0x%x, order=%d, oomkilladj=%d\n",
-                        current->comm, gfp_mask, order, current->oomkilladj);
                 task_lock(current);
+                printk(KERN_WARNING "%s invoked oom-killer: "
+                        "gfp_mask=0x%x, order=%d, oom_adj=%d\n",
+                        current->comm, gfp_mask, order,
+                        current->mm ? current->mm->oom_adj : OOM_DISABLE);
                 cpuset_print_task_mems_allowed(current);
                 task_unlock(current);
                 dump_stack();
@@ -403,8 +394,9 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
         /*
          * If the task is already exiting, don't alarm the sysadmin or kill
          * its children or threads, just set TIF_MEMDIE so it can die quickly
+         * if its mm is still attached.
          */
-        if (p->flags & PF_EXITING) {
+        if (p->mm && (p->flags & PF_EXITING)) {
                 __oom_kill_task(p, 0);
                 return 0;
         }