ec/fini: Fix race with ec_fini and ec_notify

During a graph cleanup, we first sent a PARENT_DOWN and wait for
a child down to ultimately free the xlator and the graph.

In the ec xlator, we cleanup the threads when we get a PARENT_DOWN event.
But a racing event like CHILD_UP or event xl_op may trigger healing threads
after threads cleanup.

So there is a chance that the threads might access a freed private variabe

Change-Id: I252d10181bb67b95900c903d479de707a8489532
fixes: bz#1703948
Signed-off-by: Mohammed Rafi KC <rkavunga@redhat.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/libglusterfs/src/xlator.c b/libglusterfs/src/xlator.c
index 292416ae449..526cd2e2e4d 100644
--- a/libglusterfs/src/xlator.c
+++ b/libglusterfs/src/xlator.c
@@ -1508,3 +1508,24 @@ mgmt_is_multiplexed_daemon(char *name)
     }
     return _gf_false;
 }
+
+gf_boolean_t
+xlator_is_cleanup_starting(xlator_t *this)
+{
+    gf_boolean_t cleanup = _gf_false;
+    glusterfs_graph_t *graph = NULL;
+    xlator_t *xl = NULL;
+
+    if (!this)
+        goto out;
+    graph = this->graph;
+
+    if (!graph)
+        goto out;
+
+    xl = graph->first;
+    if (xl && xl->cleanup_starting)
+        cleanup = _gf_true;
+out:
+    return cleanup;
+}