igt/gem_evict_everything: Use mlock to reduce available memory

The idea here is to check what happens when a large process requests
memory from us - we create and utilize a bunch of surfaces then have to
relinquish some but continue using the whole working set (so as to force
reloads).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

tests/gem_userptr_blits.c

@@ -1028,6 +1028,12 @@ static void test_forking_evictions(int fd, int size, int count,
 	reset_handle_ptr();
 }
 
+static void test_mlocked_evictions(int fd, int size, int count)
+{
+	mlocked_evictions(fd, &fault_ops, size, count);
+	reset_handle_ptr();
+}
+
 static void test_swapping_evictions(int fd, int size, int count)
 {
 	int trash_count;
@@ -1395,6 +1401,9 @@ int main(int argc, char **argv)
 		}
 	}
 
+	igt_subtest("mlocked-unsync-normal")
+		test_mlocked_evictions(fd, size, count);
+
 	igt_subtest("swapping-unsync-normal")
 		test_swapping_evictions(fd, size, count);
 
@@ -1416,6 +1425,9 @@ int main(int argc, char **argv)
 
 	igt_fork_signal_helper();
 
+	igt_subtest("mlocked-unsync-interruptible")
+		test_mlocked_evictions(fd, size, count);
+
 	igt_subtest("swapping-unsync-interruptible")
 		test_swapping_evictions(fd, size, count);
 
@@ -1495,6 +1507,9 @@ int main(int argc, char **argv)
 		}
 	}
 
+	igt_subtest("mlocked-normal-sync")
+		test_mlocked_evictions(fd, size, count);
+
 	igt_subtest("swapping-normal-sync")
 		test_swapping_evictions(fd, size, count);
 
@@ -1516,6 +1531,9 @@ int main(int argc, char **argv)
 
 	igt_fork_signal_helper();
 
+	igt_subtest("mlocked-sync-interruptible")
+		test_mlocked_evictions(fd, size, count);
+
 	igt_subtest("swapping-sync-interruptible")
 		test_swapping_evictions(fd, size, count);