From 40bf7eb304b5659991ed932c0cd5bee6a7c88f4f Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 16 Mar 2018 10:33:49 -0400 Subject: [PATCH] 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: Chuck Lever Signed-off-by: Anna Schumaker --- include/trace/events/sunrpc.h | 45 +++++++++++++++++++++++++++++++++++ net/sunrpc/stats.c | 16 +++++++++---- 2 files changed, 56 insertions(+), 5 deletions(-) diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h index 53bbaeac08dd..fda9e726f1cc 100644 --- a/include/trace/events/sunrpc.h +++ b/include/trace/events/sunrpc.h @@ -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(). diff --git a/net/sunrpc/stats.c b/net/sunrpc/stats.c index 1e671333c3d5..f68aa46c9dd7 100644 --- a/net/sunrpc/stats.c +++ b/net/sunrpc/stats.c @@ -24,6 +24,8 @@ #include #include +#include + #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); -- GitLab