mm, oom: change type of oom_score_adj to short

The maximum oom_score_adj is 1000 and the minimum oom_score_adj is -1000,
so this range can be represented by the signed short type with no
functional change.  The extra space this frees up in struct signal_struct
will be used for per-thread oom kill flags in the next patch.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 7 insertions, 7 deletions

diff --git a/mm/ksm.c b/mm/ksm.c
index 31ae5ea1eac..b4d5a9deb17 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1919,7 +1919,7 @@ static ssize_t run_store(struct kobject *kobj, struct kobj_attribute *attr,
 	if (ksm_run != flags) {
 		ksm_run = flags;
 		if (flags & KSM_RUN_UNMERGE) {
-			int oom_score_adj;
+			short oom_score_adj;
 
 			oom_score_adj = test_set_oom_score_adj(OOM_SCORE_ADJ_MAX);
 			err = unmerge_and_remove_all_rmap_items();
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 7e9e9113bd0..37ab4c5ab6e 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -53,7 +53,7 @@ static DEFINE_SPINLOCK(zone_scan_lock);
  * @old_val.  Usually used to reinstate a previous value to prevent racing with
  * userspacing tuning the value in the interim.
  */
-void compare_swap_oom_score_adj(int old_val, int new_val)
+void compare_swap_oom_score_adj(short old_val, short new_val)
 {
 	struct sighand_struct *sighand = current->sighand;
 
@@ -72,7 +72,7 @@ void compare_swap_oom_score_adj(int old_val, int new_val)
  * synchronization and returns the old value.  Usually used to temporarily
  * set a value, save the old value in the caller, and then reinstate it later.
  */
-int test_set_oom_score_adj(int new_val)
+short test_set_oom_score_adj(short new_val)
 {
 	struct sighand_struct *sighand = current->sighand;
 	int old_val;
@@ -193,7 +193,7 @@ unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg,
 	if (!p)
 		return 0;
 
-	adj = p->signal->oom_score_adj;
+	adj = (long)p->signal->oom_score_adj;
 	if (adj == OOM_SCORE_ADJ_MIN) {
 		task_unlock(p);
 		return 0;
@@ -399,7 +399,7 @@ static void dump_tasks(const struct mem_cgroup *memcg, const nodemask_t *nodemas
 			continue;
 		}
 
-		pr_info("[%5d] %5d %5d %8lu %8lu %7lu %8lu         %5d %s\n",
+		pr_info("[%5d] %5d %5d %8lu %8lu %7lu %8lu         %5hd %s\n",
 			task->pid, from_kuid(&init_user_ns, task_uid(task)),
 			task->tgid, task->mm->total_vm, get_mm_rss(task->mm),
 			task->mm->nr_ptes,
@@ -415,7 +415,7 @@ static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order,
 {
 	task_lock(current);
 	pr_warning("%s invoked oom-killer: gfp_mask=0x%x, order=%d, "
-		"oom_score_adj=%d\n",
+		"oom_score_adj=%hd\n",
 		current->comm, gfp_mask, order,
 		current->signal->oom_score_adj);
 	cpuset_print_task_mems_allowed(current);
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 0fbb45283c6..bb6f6a04e92 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1498,7 +1498,7 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
 	struct address_space *mapping;
 	struct inode *inode;
 	struct filename *pathname;
-	int oom_score_adj;
+	short oom_score_adj;
 	int i, type, prev;
 	int err;