gluster: Sometimes Brick process is crashed at the time of stopping brick

Problem: Sometimes brick process is getting crashed at the time
         of stop brick while brick mux is enabled.

Solution: Brick process was getting crashed because of rpc connection
          was not cleaning properly while brick mux is enabled.In this patch
          after sending GF_EVENT_CLEANUP notification to xlator(server)
          waits for all rpc client connection destroy for specific xlator.Once rpc
          connections are destroyed in server_rpc_notify for all associated client
          for that brick then call xlator_mem_cleanup for for brick xlator as well as
          all child xlators.To avoid races at the time of cleanup introduce
          two new flags at each xlator cleanup_starting, call_cleanup.

BUG: 1544090
Signed-off-by: Mohit Agrawal <moagrawa@redhat.com>

Note: Run all test-cases in separate build (https://review.gluster.org/#/c/19700/)
      with same patch after enable brick mux forcefully, all test cases are
      passed.

Change-Id: Ic4ab9c128df282d146cf1135640281fcb31997bf
updates: bz#1544090

1 files changed, 10 insertions, 1 deletions

diff --git a/libglusterfs/src/xlator.h b/libglusterfs/src/xlator.h
index 2f8fed6bb64..3c16758e1a9 100644
--- a/libglusterfs/src/xlator.h
+++ b/libglusterfs/src/xlator.h
@@ -1043,6 +1043,14 @@ struct _xlator {
         /* Is this pass_through? */
         gf_boolean_t   pass_through;
         struct xlator_fops    *pass_through_fops;
+
+        /* cleanup flag to avoid races during xlator cleanup */
+        uint32_t cleanup_starting;
+
+        /* flag to avoid recall of xlator_mem_cleanup for xame xlator */
+        uint32_t call_cleanup;
+
+
 };
 
 typedef struct {
@@ -1236,5 +1244,6 @@ copy_opts_to_child (xlator_t *src, xlator_t *dst, char *glob);
 int
 glusterfs_delete_volfile_checksum (glusterfs_ctx_t *ctx,
                                    const char *volfile_id);
-
+int
+xlator_memrec_free (xlator_t *xl);
 #endif /* _XLATOR_H */