summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMatthew Wilcox <mawilcox@microsoft.com>2016-12-14 15:08:11 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-14 16:04:09 -0800
commitba20cd60c97945f0de9fe313f869b3a5855e1503 (patch)
tree35a39c27248705e7c736c9ee5bfa1d22d69a3a2e
parent061ef3936b16edc8f779d403d569392505665ed5 (diff)
radix tree test suite: iteration test misuses RCU
Each thread needs to register itself with RCU, otherwise the reading thread's read lock has no effect and the freeing thread will free the memory in the tree without waiting for the read lock to be dropped. Link: http://lkml.kernel.org/r/1480369871-5271-42-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>
-rw-r--r--tools/testing/radix-tree/iteration_check.c28
1 files changed, 26 insertions, 2 deletions
diff --git a/tools/testing/radix-tree/iteration_check.c b/tools/testing/radix-tree/iteration_check.c
index 11d570c3fc83..df71cb841385 100644
--- a/tools/testing/radix-tree/iteration_check.c
+++ b/tools/testing/radix-tree/iteration_check.c
@@ -29,6 +29,8 @@ static void *add_entries_fn(void *arg)
{
int pgoff;
+ rcu_register_thread();
+
while (!test_complete) {
for (pgoff = 0; pgoff < 100; pgoff++) {
pthread_mutex_lock(&tree_lock);
@@ -38,6 +40,8 @@ static void *add_entries_fn(void *arg)
}
}
+ rcu_unregister_thread();
+
return NULL;
}
@@ -53,6 +57,8 @@ static void *tagged_iteration_fn(void *arg)
struct radix_tree_iter iter;
void **slot;
+ rcu_register_thread();
+
while (!test_complete) {
rcu_read_lock();
radix_tree_for_each_tagged(slot, &tree, &iter, 0, TAG) {
@@ -72,12 +78,18 @@ static void *tagged_iteration_fn(void *arg)
continue;
}
- if (rand_r(&seeds[0]) % 50 == 0)
+ if (rand_r(&seeds[0]) % 50 == 0) {
slot = radix_tree_iter_next(&iter);
+ rcu_read_unlock();
+ rcu_barrier();
+ rcu_read_lock();
+ }
}
rcu_read_unlock();
}
+ rcu_unregister_thread();
+
return NULL;
}
@@ -93,6 +105,8 @@ static void *untagged_iteration_fn(void *arg)
struct radix_tree_iter iter;
void **slot;
+ rcu_register_thread();
+
while (!test_complete) {
rcu_read_lock();
radix_tree_for_each_slot(slot, &tree, &iter, 0) {
@@ -112,12 +126,18 @@ static void *untagged_iteration_fn(void *arg)
continue;
}
- if (rand_r(&seeds[1]) % 50 == 0)
+ if (rand_r(&seeds[1]) % 50 == 0) {
slot = radix_tree_iter_next(&iter);
+ rcu_read_unlock();
+ rcu_barrier();
+ rcu_read_lock();
+ }
}
rcu_read_unlock();
}
+ rcu_unregister_thread();
+
return NULL;
}
@@ -127,6 +147,8 @@ static void *untagged_iteration_fn(void *arg)
*/
static void *remove_entries_fn(void *arg)
{
+ rcu_register_thread();
+
while (!test_complete) {
int pgoff;
@@ -137,6 +159,8 @@ static void *remove_entries_fn(void *arg)
pthread_mutex_unlock(&tree_lock);
}
+ rcu_unregister_thread();
+
return NULL;
}