RDMA/core: Get sum value of all counters when perform a sysfs stat read

Since a QP can only be bound to one counter, then if it is bound to a
separate counter, for backward compatibility purpose, the statistic value
must be:
* stat of default counter
+ stat of all running allocated counters
+ stat of all deallocated counters (history stats)

Signed-off-by: Mark Zhang <markz@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

include/rdma/rdma_counter.h

@@ -27,6 +27,7 @@ struct rdma_counter_mode {
 
 struct rdma_port_counter {
 	struct rdma_counter_mode mode;
+	struct rdma_hw_stats *hstats;
 	struct mutex lock;
 };
 
@@ -49,5 +50,6 @@ int rdma_counter_bind_qp_auto(struct ib_qp *qp, u8 port);
 int rdma_counter_unbind_qp(struct ib_qp *qp, bool force);
 
 int rdma_counter_query_stats(struct rdma_counter *counter);
+u64 rdma_counter_get_hwstat_value(struct ib_device *dev, u8 port, u32 index);
 
 #endif /* _RDMA_COUNTER_H_ */