Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 40bf7eb3 authored by Chuck Lever's avatar Chuck Lever Committed by Anna Schumaker
Browse files

sunrpc: Add static trace point to report RPC latency stats 



Introduce a low-overhead mechanism to report information about
latencies of individual RPCs. The goal is to enable user space to
filter the trace record for latency outliers, or build histograms,
etc.

Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
parent e671edb9

include/trace/events/sunrpc.h

+45 −0
Original line number Diff line number Diff line
@@ -212,6 +212,51 @@ DEFINE_EVENT(rpc_task_queued, rpc_task_wakeup, 


);



TRACE_EVENT(rpc_stats_latency,



	TP_PROTO(

		const struct rpc_task *task,

		ktime_t backlog,

		ktime_t rtt,

		ktime_t execute

	),



	TP_ARGS(task, backlog, rtt, execute),



	TP_STRUCT__entry(

		__field(u32, xid)

		__field(int, version)

		__string(progname, task->tk_client->cl_program->name)

		__string(procname, rpc_proc_name(task))

		__field(unsigned long, backlog)

		__field(unsigned long, rtt)

		__field(unsigned long, execute)

		__string(addr,

			 task->tk_xprt->address_strings[RPC_DISPLAY_ADDR])

		__string(port,

			 task->tk_xprt->address_strings[RPC_DISPLAY_PORT])

	),



	TP_fast_assign(

		__entry->xid = be32_to_cpu(task->tk_rqstp->rq_xid);

		__entry->version = task->tk_client->cl_vers;

		__assign_str(progname, task->tk_client->cl_program->name)

		__assign_str(procname, rpc_proc_name(task))

		__entry->backlog = ktime_to_us(backlog);

		__entry->rtt = ktime_to_us(rtt);

		__entry->execute = ktime_to_us(execute);

		__assign_str(addr,

			     task->tk_xprt->address_strings[RPC_DISPLAY_ADDR]);

		__assign_str(port,

			     task->tk_xprt->address_strings[RPC_DISPLAY_PORT]);

	),



	TP_printk("peer=[%s]:%s xid=0x%08x %sv%d %s backlog=%lu rtt=%lu execute=%lu",

		__get_str(addr), __get_str(port), __entry->xid,

		__get_str(progname), __entry->version, __get_str(procname),

		__entry->backlog, __entry->rtt, __entry->execute)

);



/*

 * First define the enums in the below macros to be exported to userspace

 * via TRACE_DEFINE_ENUM().

net/sunrpc/stats.c

+11 −5
Original line number Diff line number Diff line
@@ -24,6 +24,8 @@ 
#include <linux/sunrpc/metrics.h>

#include <linux/rcupdate.h>



#include <trace/events/sunrpc.h>



#include "netns.h"



#define RPCDBG_FACILITY	RPCDBG_MISC
@@ -148,7 +150,7 @@ void rpc_count_iostats_metrics(const struct rpc_task *task, 
			       struct rpc_iostats *op_metrics)

{

	struct rpc_rqst *req = task->tk_rqstp;

	ktime_t delta, now;

	ktime_t backlog, execute, now;



	if (!op_metrics || !req)

		return;
@@ -164,16 +166,20 @@ void rpc_count_iostats_metrics(const struct rpc_task *task, 
	op_metrics->om_bytes_sent += req->rq_xmit_bytes_sent;

	op_metrics->om_bytes_recv += req->rq_reply_bytes_recvd;



	backlog = 0;

	if (ktime_to_ns(req->rq_xtime)) {

		delta = ktime_sub(req->rq_xtime, task->tk_start);

		op_metrics->om_queue = ktime_add(op_metrics->om_queue, delta);

		backlog = ktime_sub(req->rq_xtime, task->tk_start);

		op_metrics->om_queue = ktime_add(op_metrics->om_queue, backlog);

	}



	op_metrics->om_rtt = ktime_add(op_metrics->om_rtt, req->rq_rtt);



	delta = ktime_sub(now, task->tk_start);

	op_metrics->om_execute = ktime_add(op_metrics->om_execute, delta);

	execute = ktime_sub(now, task->tk_start);

	op_metrics->om_execute = ktime_add(op_metrics->om_execute, execute);



	spin_unlock(&op_metrics->om_lock);



	trace_rpc_stats_latency(req->rq_task, backlog, req->rq_rtt, execute);

}

EXPORT_SYMBOL_GPL(rpc_count_iostats_metrics);