locks: added inodelk/entrylk contention upcall notifications

The locks xlator now is able to send a contention notification to
the current owner of the lock.

This is only a notification that can be used to improve performance
of some client side operations that might benefit from extended
duration of lock ownership. Nothing is done if the lock owner decides
to ignore the message and to not release the lock. For forced
release of acquired resources, leases must be used.

Change-Id: I7f1ad32a0b4b445505b09908a050080ad848f8e0
Signed-off-by: Xavier Hernandez <xhernandez@datalab.es>

1 files changed, 8 insertions, 0 deletions

diff --git a/xlators/features/locks/src/locks.h b/xlators/features/locks/src/locks.h
index 3d3b327f56c..c2edfff8f00 100644
--- a/xlators/features/locks/src/locks.h
+++ b/xlators/features/locks/src/locks.h
@@ -70,6 +70,7 @@ typedef struct __posix_lock posix_lock_t;
 struct __pl_inode_lock {
         struct list_head   list;
         struct list_head   blocked_locks; /* list_head pointing to blocked_inodelks */
+        struct list_head   contend; /* list of contending locks */
         int                ref;
 
         short              fl_type;
@@ -86,6 +87,8 @@ struct __pl_inode_lock {
 
         struct timeval     blkd_time;   /*time at which lock was queued into blkd list*/
         struct timeval     granted_time; /*time at which lock was queued into active list*/
+        /*last time at wich lock contention was detected and notified*/
+        struct timespec    contention_time;
 
         /* These two together serve to uniquely identify each process
            across nodes */
@@ -120,6 +123,7 @@ typedef struct _pl_dom_list pl_dom_list_t;
 struct __entry_lock {
         struct list_head  domain_list;    /* list_head back to pl_dom_list_t */
         struct list_head  blocked_locks; /* list_head back to blocked_entrylks */
+        struct list_head  contend;       /* list of contending locks */
 	int ref;
 
         call_frame_t     *frame;
@@ -133,6 +137,8 @@ struct __entry_lock {
 
         struct timeval     blkd_time;   /*time at which lock was queued into blkd list*/
         struct timeval     granted_time; /*time at which lock was queued into active list*/
+        /*last time at wich lock contention was detected and notified*/
+        struct timespec    contention_time;
 
         void             *client;
         gf_lkowner_t      owner;
@@ -194,6 +200,8 @@ typedef struct {
         uint32_t        revocation_secs;
         gf_boolean_t    revocation_clear_all;
         uint32_t        revocation_max_blocked;
+        gf_boolean_t    notify_contention;
+        uint32_t        notify_contention_delay;
 } posix_locks_private_t;