mm/vmalloc.c: convert vmap_lazy_nr to atomic_long_t

vmap_lazy_nr variable has atomic_t type that is 4 bytes integer value on
both 32 and 64 bit systems.  lazy_max_pages() deals with "unsigned long"
that is 8 bytes on 64 bit system, thus vmap_lazy_nr should be 8 bytes on
64 bit as well.

Link: http://lkml.kernel.org/r/20190131162452.25879-1-urezki@gmail.comSigned-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Joel Fernandes <joelaf@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmalloc.c

@@ -633,7 +633,7 @@ static unsigned long lazy_max_pages(void)
 	return log * (32UL * 1024 * 1024 / PAGE_SIZE);
 }
 
-static atomic_t vmap_lazy_nr = ATOMIC_INIT(0);
+static atomic_long_t vmap_lazy_nr = ATOMIC_LONG_INIT(0);
 
 /*
  * Serialize vmap purging.  There is no actual criticial section protected
@@ -651,7 +651,7 @@ static void purge_fragmented_blocks_allcpus(void);
  */
 void set_iounmap_nonlazy(void)
 {
-	atomic_set(&vmap_lazy_nr, lazy_max_pages()+1);
+	atomic_long_set(&vmap_lazy_nr, lazy_max_pages()+1);
 }
 
 /*
@@ -659,10 +659,10 @@ void set_iounmap_nonlazy(void)
  */
 static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)
 {
+	unsigned long resched_threshold;
 	struct llist_node *valist;
 	struct vmap_area *va;
 	struct vmap_area *n_va;
-	int resched_threshold;
 
 	lockdep_assert_held(&vmap_purge_lock);
 
@@ -682,16 +682,16 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)
 	}
 
 	flush_tlb_kernel_range(start, end);
-	resched_threshold = (int) lazy_max_pages() << 1;
+	resched_threshold = lazy_max_pages() << 1;
 
 	spin_lock(&vmap_area_lock);
 	llist_for_each_entry_safe(va, n_va, valist, purge_list) {
-		int nr = (va->va_end - va->va_start) >> PAGE_SHIFT;
+		unsigned long nr = (va->va_end - va->va_start) >> PAGE_SHIFT;
 
 		__free_vmap_area(va);
-		atomic_sub(nr, &vmap_lazy_nr);
+		atomic_long_sub(nr, &vmap_lazy_nr);
 
-		if (atomic_read(&vmap_lazy_nr) < resched_threshold)
+		if (atomic_long_read(&vmap_lazy_nr) < resched_threshold)
 			cond_resched_lock(&vmap_area_lock);
 	}
 	spin_unlock(&vmap_area_lock);
@@ -728,10 +728,10 @@ static void purge_vmap_area_lazy(void)
  */
 static void free_vmap_area_noflush(struct vmap_area *va)
 {
-	int nr_lazy;
+	unsigned long nr_lazy;
 
-	nr_lazy = atomic_add_return((va->va_end - va->va_start) >> PAGE_SHIFT,
-				    &vmap_lazy_nr);
+	nr_lazy = atomic_long_add_return((va->va_end - va->va_start) >>
+				PAGE_SHIFT, &vmap_lazy_nr);
 
 	/* After this point, we may free va at any time */
 	llist_add(&va->purge_list, &vmap_purge_list);