Add a new function and its RPC caller. By using it, we can
get the statistics of all the bdevs or the specified bdev.
Meanwhile, with this patch, the open source tool 'sysstat/iostat'
can support for SPDK. The 'iostat' tool can call this function to
get the statistics of all the SPDK managed devices via the rpc
interface.
Change-Id: I135a7bbd49d923014bdf93720f78dd5a588d7afa
Signed-off-by: Yanbo Zhou <yanbo.zhou@intel.com>
Reviewed-on: https://review.gerrithub.io/393130
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
64ccd4b95b