gru: collect per-context user statistics

Collect GRU statistics for each user GRU context.  Statistics are kept for
TLB misses & content resource contention.  Add user request for retrieving
the statistics.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/misc/sgi-gru/grufile.c

@@ -251,6 +251,9 @@ static long gru_file_unlocked_ioctl(struct file *file, unsigned int req,
 	case GRU_USER_CALL_OS:
 		err = gru_handle_user_call_os(arg);
 		break;
+	case GRU_GET_GSEG_STATISTICS:
+		err = gru_get_gseg_statistics(arg);
+		break;
 	case GRU_KTEST:
 		err = gru_ktest(arg);
 		break;