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>

4 files changed, 11 insertions, 11 deletions

diff --git a/include/linux/oom.h b/include/linux/oom.h
index 4a4188d..922dab1 100644
--- a/include/linux/oom.h
+++ b/include/linux/oom.h
@@ -29,8 +29,8 @@ enum oom_scan_t {
 	OOM_SCAN_SELECT,	/* always select this thread first */
 };
 
-extern void compare_swap_oom_score_adj(int old_val, int new_val);
-extern int test_set_oom_score_adj(int new_val);
+extern void compare_swap_oom_score_adj(short old_val, short new_val);
+extern short test_set_oom_score_adj(short new_val);
 
 extern unsigned long oom_badness(struct task_struct *p,
 		struct mem_cgroup *memcg, const nodemask_t *nodemask,
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 0dd42a0..ed30456 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -631,9 +631,9 @@ struct signal_struct {
 	struct rw_semaphore group_rwsem;
 #endif
 
-	int oom_score_adj;	/* OOM kill score adjustment */
-	int oom_score_adj_min;	/* OOM kill score adjustment minimum value.
-				 * Only settable by CAP_SYS_RESOURCE. */
+	short oom_score_adj;		/* OOM kill score adjustment */
+	short oom_score_adj_min;	/* OOM kill score adjustment min value.
+					 * Only settable by CAP_SYS_RESOURCE. */
 
 	struct mutex cred_guard_mutex;	/* guard against foreign influences on
 					 * credential calculations
diff --git a/include/trace/events/oom.h b/include/trace/events/oom.h
index dd4ba3b..1e97498 100644
--- a/include/trace/events/oom.h
+++ b/include/trace/events/oom.h
@@ -14,7 +14,7 @@ TRACE_EVENT(oom_score_adj_update,
 	TP_STRUCT__entry(
 		__field(	pid_t,	pid)
 		__array(	char,	comm,	TASK_COMM_LEN )
-		__field(	 int,	oom_score_adj)
+		__field(	short,	oom_score_adj)
 	),
 
 	TP_fast_assign(
@@ -23,7 +23,7 @@ TRACE_EVENT(oom_score_adj_update,
 		__entry->oom_score_adj = task->signal->oom_score_adj;
 	),
 
-	TP_printk("pid=%d comm=%s oom_score_adj=%d",
+	TP_printk("pid=%d comm=%s oom_score_adj=%hd",
 		__entry->pid, __entry->comm, __entry->oom_score_adj)
 );
 
diff --git a/include/trace/events/task.h b/include/trace/events/task.h
index b53add0..102a646 100644
--- a/include/trace/events/task.h
+++ b/include/trace/events/task.h
@@ -15,7 +15,7 @@ TRACE_EVENT(task_newtask,
 		__field(	pid_t,	pid)
 		__array(	char,	comm, TASK_COMM_LEN)
 		__field( unsigned long, clone_flags)
-		__field(	int,    oom_score_adj)
+		__field(	short,	oom_score_adj)
 	),
 
 	TP_fast_assign(
@@ -25,7 +25,7 @@ TRACE_EVENT(task_newtask,
 		__entry->oom_score_adj = task->signal->oom_score_adj;
 	),
 
-	TP_printk("pid=%d comm=%s clone_flags=%lx oom_score_adj=%d",
+	TP_printk("pid=%d comm=%s clone_flags=%lx oom_score_adj=%hd",
 		__entry->pid, __entry->comm,
 		__entry->clone_flags, __entry->oom_score_adj)
 );
@@ -40,7 +40,7 @@ TRACE_EVENT(task_rename,
 		__field(	pid_t,	pid)
 		__array(	char, oldcomm,  TASK_COMM_LEN)
 		__array(	char, newcomm,  TASK_COMM_LEN)
-		__field(	int, oom_score_adj)
+		__field(	short,	oom_score_adj)
 	),
 
 	TP_fast_assign(
@@ -50,7 +50,7 @@ TRACE_EVENT(task_rename,
 		__entry->oom_score_adj = task->signal->oom_score_adj;
 	),
 
-	TP_printk("pid=%d oldcomm=%s newcomm=%s oom_score_adj=%d",
+	TP_printk("pid=%d oldcomm=%s newcomm=%s oom_score_adj=%hd",
 		__entry->pid, __entry->oldcomm,
 		__entry->newcomm, __entry->oom_score_adj)
 );