1 files changed, 8 insertions, 9 deletions

diff --git a/mm/nommu.c b/mm/nommu.c
index 72eda4aee2cb..b571ef707428 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -62,11 +62,11 @@ void *high_memory;
 struct page *mem_map;
 unsigned long max_mapnr;
 unsigned long num_physpages;
-atomic_long_t vm_committed_space = ATOMIC_LONG_INIT(0);
+struct percpu_counter vm_committed_as;
 int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */
 int sysctl_overcommit_ratio = 50; /* default is 50% */
 int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT;
-int sysctl_nr_trim_pages = 1; /* page trimming behaviour */
+int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS;
 int heap_stack_gap = 0;
 
 atomic_long_t mmap_pages_allocated;
@@ -463,6 +463,10 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
  */
 void __init mmap_init(void)
 {
+        int ret;
+
+        ret = percpu_counter_init(&vm_committed_as, 0);
+        VM_BUG_ON(ret);
         vm_region_jar = KMEM_CACHE(vm_region, SLAB_PANIC);
 }
 
@@ -511,8 +515,6 @@ static void add_nommu_region(struct vm_region *region)
 
         validate_nommu_regions();
 
-        BUG_ON(region->vm_start & ~PAGE_MASK);
-
         parent = NULL;
         p = &nommu_region_tree.rb_node;
         while (*p) {
@@ -1847,12 +1849,9 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
         if (mm)
                 allowed -= mm->total_vm / 32;
 
-        /*
-         * cast `allowed' as a signed long because vm_committed_space
-         * sometimes has a negative value
-         */
-        if (atomic_long_read(&vm_committed_space) < (long)allowed)
+        if (percpu_counter_read_positive(&vm_committed_as) < allowed)
                 return 0;
+
 error:
         vm_unacct_memory(pages);