X-Git-Url: http://git.monstr.eu/?a=blobdiff_plain;f=kernel%2Ffork.c;h=7a08025d2c99ce904920151e701cdcf9f0233519;hb=313c08c72ee7f87c54e34baec5cc4f4005e8800d;hp=89b8b6c085921a605c0633de4e8bd0af589f788a;hpb=8715c6d3100fc7c6edddf29af4a399a1c12d028c;p=linux-2.6-microblaze.git

diff --git a/kernel/fork.c b/kernel/fork.c
index 89b8b6c08592..7a08025d2c99 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -756,8 +756,13 @@ static void check_mm(struct mm_struct *mm)
 			 "Please make sure 'struct resident_page_types[]' is updated as well");
 
 	for (i = 0; i < NR_MM_COUNTERS; i++) {
-		long x = atomic_long_read(&mm->rss_stat.count[i]);
+		long x = percpu_counter_sum(&mm->rss_stat[i]);
 
+		if (likely(!x))
+			continue;
+
+		/* Making sure this is not due to race with CPU offlining. */
+		x = percpu_counter_sum_all(&mm->rss_stat[i]);
 		if (unlikely(x))
 			pr_alert("BUG: Bad rss-counter state mm:%p type:%s val:%ld\n",
 				 mm, resident_page_types[i], x);
@@ -782,6 +787,8 @@ static void check_mm(struct mm_struct *mm)
  */
 void __mmdrop(struct mm_struct *mm)
 {
+	int i;
+
 	BUG_ON(mm == &init_mm);
 	WARN_ON_ONCE(mm == current->mm);
 	WARN_ON_ONCE(mm == current->active_mm);
@@ -791,6 +798,9 @@ void __mmdrop(struct mm_struct *mm)
 	check_mm(mm);
 	put_user_ns(mm->user_ns);
 	mm_pasid_drop(mm);
+
+	for (i = 0; i < NR_MM_COUNTERS; i++)
+		percpu_counter_destroy(&mm->rss_stat[i]);
 	free_mm(mm);
 }
 EXPORT_SYMBOL_GPL(__mmdrop);
@@ -1110,6 +1120,8 @@ static void mm_init_uprobes_state(struct mm_struct *mm)
 static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
 	struct user_namespace *user_ns)
 {
+	int i;
+
 	mt_init_flags(&mm->mm_mt, MM_MT_FLAGS);
 	mt_set_external_lock(&mm->mm_mt, &mm->mmap_lock);
 	atomic_set(&mm->mm_users, 1);
@@ -1151,10 +1163,17 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
 	if (init_new_context(p, mm))
 		goto fail_nocontext;
 
+	for (i = 0; i < NR_MM_COUNTERS; i++)
+		if (percpu_counter_init(&mm->rss_stat[i], 0, GFP_KERNEL_ACCOUNT))
+			goto fail_pcpu;
+
 	mm->user_ns = get_user_ns(user_ns);
 	lru_gen_init_mm(mm);
 	return mm;
 
+fail_pcpu:
+	while (i > 0)
+		percpu_counter_destroy(&mm->rss_stat[--i]);
 fail_nocontext:
 	mm_free_pgd(mm);
 fail_nopgd: