xlators: add JSON FOP statistics dumps every N seconds

Summary:
- Adds a thread to the io-stats translator which dumps out statistics
  every N seconds where N is configurable by an option called
  "diagnostics.stats-dump-interval"
- Thread cleanly starts/stops when translator is unloaded
- Updates macros to use "Atomic Builtins" (e.g. intel CPU extentions) to
  use memory barries to update counters vs using locks.  This should
  reduce overhead and prevent any deadlock bugs due to lock contention.

Test Plan:
- Test on development machine
- Run prove -v tests/basic/stats-dump.t

Change-Id: If071239d8fdc185e4e8fd527363cc042447a245d
BUG: 1266476
Signed-off-by: Jeff Darcy <jdarcy@redhat.com>
Reviewed-on: http://review.gluster.org/12209
Tested-by: NetBSD Build System <jenkins@build.gluster.org>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Avra Sengupta <asengupt@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/libglusterfs/src/xlator.h b/libglusterfs/src/xlator.h
index d7dbfb413be..27b598d7e60 100644
--- a/libglusterfs/src/xlator.h
+++ b/libglusterfs/src/xlator.h
@@ -853,6 +853,7 @@ struct _xlator {
         /* Built during parsing */
         char          *name;
         char          *type;
+        char          *instance_name;  /* Used for multi NFSd */
         xlator_t      *next;
         xlator_t      *prev;
         xlator_list_t *parents;