radix tree test suite: use rcu_barrier

Calling rcu_barrier() allows all of the rcu-freed memory to be actually
returned to the pool, and allows nr_allocated to return to 0.  As well
as allowing diffs between runs to be more useful, it also lets us
pinpoint leaks more effectively.

Link: http://lkml.kernel.org/r/1480369871-5271-44-git-send-email-mawilcox@linuxonhyperv.com
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/testing/radix-tree/main.c

@@ -295,24 +295,31 @@ static void single_thread_tests(bool long_run)
 	printf("starting single_thread_tests: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 	multiorder_checks();
+	rcu_barrier();
 	printf("after multiorder_check: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 	locate_check();
+	rcu_barrier();
 	printf("after locate_check: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 	tag_check();
+	rcu_barrier();
 	printf("after tag_check: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 	gang_check();
+	rcu_barrier();
 	printf("after gang_check: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 	add_and_check();
+	rcu_barrier();
 	printf("after add_and_check: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 	dynamic_height_check();
+	rcu_barrier();
 	printf("after dynamic_height_check: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 	big_gang_check(long_run);
+	rcu_barrier();
 	printf("after big_gang_check: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 	for (i = 0; i < (long_run ? 2000 : 3); i++) {
@@ -320,6 +327,7 @@ static void single_thread_tests(bool long_run)
 		printf("%d ", i);
 		fflush(stdout);
 	}
+	rcu_barrier();
 	printf("after copy_tag_check: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 }
@@ -354,8 +362,8 @@ int main(int argc, char **argv)
 
 	benchmark();
 
-	sleep(1);
-	printf("after sleep(1): %d allocated, preempt %d\n",
+	rcu_barrier();
+	printf("after rcu_barrier: %d allocated, preempt %d\n",
 		nr_allocated, preempt_count);
 	rcu_unregister_thread();
 

tools/testing/radix-tree/tag_check.c

@@ -51,6 +51,7 @@ void simple_checks(void)
 	verify_tag_consistency(&tree, 1);
 	printf("before item_kill_tree: %d allocated\n", nr_allocated);
 	item_kill_tree(&tree);
+	rcu_barrier();
 	printf("after item_kill_tree: %d allocated\n", nr_allocated);
 }
 
@@ -331,12 +332,16 @@ void tag_check(void)
 	single_check();
 	extend_checks();
 	contract_checks();
+	rcu_barrier();
 	printf("after extend_checks: %d allocated\n", nr_allocated);
 	__leak_check();
 	leak_check();
+	rcu_barrier();
 	printf("after leak_check: %d allocated\n", nr_allocated);
 	simple_checks();
+	rcu_barrier();
 	printf("after simple_checks: %d allocated\n", nr_allocated);
 	thrash_tags();
+	rcu_barrier();
 	printf("after thrash_tags: %d allocated\n", nr_allocated);
 }