[PATCH v1 09/15] SUNRPC: trace RPC client lifetime events

Chuck Lever
2020-05-12T21:13:43Z

The "create" tracepoint records parts of the rpc_create arguments,
and the shutdown tracepoint records when the rpc_clnt is about to
signal pending tasks and destroy auths.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
include/trace/events/sunrpc.h | 111 +++++++++++++++++++++++++++++++++++++++++
net/sunrpc/clnt.c | 39 ++++++--------
2 files changed, 126 insertions(+), 24 deletions(-)

diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h
index fc8a969ba306..098c84750fb7 100644
--- a/include/trace/events/sunrpc.h
+++ b/include/trace/events/sunrpc.h
@@ -65,6 +65,117 @@
DEFINE_RPCXDRBUF_EVENT(reply_pages);

+DECLARE_EVENT_CLASS(rpc_clnt_class,
+ TP_PROTO(
+ const struct rpc_clnt *clnt
+ ),
+
+ TP_ARGS(clnt),
+
+ TP_STRUCT__entry(
+ __field(unsigned int, client_id)
+ ),
+
+ TP_fast_assign(
+ __entry->client_id = clnt->cl_clid;
+ ),
+
+ TP_printk("clid=%u", __entry->client_id)
+);
+
+#define DEFINE_RPC_CLNT_EVENT(name) \
+ DEFINE_EVENT(rpc_clnt_class, \
+ rpc_clnt_##name, \
+ TP_PROTO( \
+ const struct rpc_clnt *clnt \
+ ), \
+ TP_ARGS(clnt))
+
+DEFINE_RPC_CLNT_EVENT(free);
+DEFINE_RPC_CLNT_EVENT(killall);
+DEFINE_RPC_CLNT_EVENT(shutdown);
+DEFINE_RPC_CLNT_EVENT(release);
+DEFINE_RPC_CLNT_EVENT(replace_xprt);
+DEFINE_RPC_CLNT_EVENT(replace_xprt_err);
+
+TRACE_EVENT(rpc_clnt_new,
+ TP_PROTO(
+ const struct rpc_clnt *clnt,
+ const struct rpc_xprt *xprt,
+ const char *program,
+ const char *server
+ ),
+
+ TP_ARGS(clnt, xprt, program, server),
+
+ TP_STRUCT__entry(
+ __field(unsigned int, client_id)
+ __string(addr, xprt->address_strings[RPC_DISPLAY_ADDR])
+ __string(port, xprt->address_strings[RPC_DISPLAY_PORT])
+ __string(program, program)
+ __string(server, server)
+ ),
+
+ TP_fast_assign(
+ __entry->client_id = clnt->cl_clid;
+ __assign_str(addr, xprt->address_strings[RPC_DISPLAY_ADDR]);
+ __assign_str(port, xprt->address_strings[RPC_DISPLAY_PORT]);
+ __assign_str(program, program)
+ __assign_str(server, server)
+ ),
+
+ TP_printk("client=%u peer=[%s]:%s program=%s server=%s",
+ __entry->client_id, __get_str(addr), __get_str(port),
+ __get_str(program), __get_str(server))
+);
+
+TRACE_EVENT(rpc_clnt_new_err,
+ TP_PROTO(
+ const char *program,
+ const char *server,
+ int error
+ ),
+
+ TP_ARGS(program, server, error),
+
+ TP_STRUCT__entry(
+ __field(int, error)
+ __string(program, program)
+ __string(server, server)
+ ),
+
+ TP_fast_assign(
+ __entry->error = error;
+ __assign_str(program, program)
+ __assign_str(server, server)
+ ),
+
+ TP_printk("program=%s server=%s error=%d",
+ __get_str(program), __get_str(server), __entry->error)
+);
+
+TRACE_EVENT(rpc_clnt_clone_err,
+ TP_PROTO(
+ const struct rpc_clnt *clnt,
+ int error
+ ),
+
+ TP_ARGS(clnt, error),
+
+ TP_STRUCT__entry(
+ __field(unsigned int, client_id)
+ __field(int, error)
+ ),
+
+ TP_fast_assign(
+ __entry->client_id = clnt->cl_clid;
+ __entry->error = error;
+ ),
+
+ TP_printk("client=%u error=%d", __entry->client_id, __entry->error)
+);
+
+
TRACE_DEFINE_ENUM(RPC_AUTH_OK);
TRACE_DEFINE_ENUM(RPC_AUTH_BADCRED);
TRACE_DEFINE_ENUM(RPC_AUTH_REJECTEDCRED);
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index c600628efa91..73d53b9898e6 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -370,10 +370,6 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
const char *nodename = args->nodename;
int err;

- /* sanity check the name before trying to print it */
- dprintk("RPC: creating %s client for %s (xprt %p)\n",
- program->name, args->servername, xprt);
-
err = rpciod_up();
if (err)
goto out_no_rpciod;
@@ -436,6 +432,8 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
goto out_no_path;
if (parent)
atomic_inc(&parent->cl_count);
+
+ trace_rpc_clnt_new(clnt, xprt, program->name, args->servername);
return clnt;

out_no_path:
@@ -450,6 +448,7 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
out_no_rpciod:
xprt_switch_put(xps);
xprt_put(xprt);
+ trace_rpc_clnt_new_err(program->name, args->servername, err);
return ERR_PTR(err);
}

@@ -634,10 +633,8 @@ static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
args->nodename = clnt->cl_nodename;

new = rpc_new_client(args, xps, xprt, clnt);
- if (IS_ERR(new)) {
- err = PTR_ERR(new);
- goto out_err;
- }
+ if (IS_ERR(new))
+ return new;

/* Turn off autobind on clones */
new->cl_autobind = 0;
@@ -650,7 +647,7 @@ static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
return new;

out_err:
- dprintk("RPC: %s: returned error %d\n", __func__, err);
+ trace_rpc_clnt_clone_err(clnt, err);
return ERR_PTR(err);
}

@@ -723,11 +720,8 @@ int rpc_switch_client_transport(struct rpc_clnt *clnt,
int err;

xprt = xprt_create_transport(args);
- if (IS_ERR(xprt)) {
- dprintk("RPC: failed to create new xprt for clnt %p\n",
- clnt);
+ if (IS_ERR(xprt))
return PTR_ERR(xprt);
- }

xps = xprt_switch_alloc(xprt, GFP_KERNEL);
if (xps == NULL) {
@@ -767,7 +761,7 @@ int rpc_switch_client_transport(struct rpc_clnt *clnt,
rpc_release_client(parent);
xprt_switch_put(oldxps);
xprt_put(old);
- dprintk("RPC: replaced xprt for clnt %p\n", clnt);
+ trace_rpc_clnt_replace_xprt(clnt);
return 0;

out_revert:
@@ -777,7 +771,7 @@ int rpc_switch_client_transport(struct rpc_clnt *clnt,
rpc_client_register(clnt, pseudoflavor, NULL);
xprt_switch_put(xps);
xprt_put(xprt);
- dprintk("RPC: failed to switch xprt for clnt %p\n", clnt);
+ trace_rpc_clnt_replace_xprt_err(clnt);
return err;
}
EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
@@ -844,10 +838,11 @@ void rpc_killall_tasks(struct rpc_clnt *clnt)

if (list_empty(&clnt->cl_tasks))
return;
- dprintk("RPC: killing all tasks for client %p\n", clnt);
+
/*
* Spin lock all_tasks to prevent changes...
*/
+ trace_rpc_clnt_killall(clnt);
spin_lock(&clnt->cl_lock);
list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
rpc_signal_task(rovr);
@@ -863,9 +858,7 @@ void rpc_shutdown_client(struct rpc_clnt *clnt)
{
might_sleep();

- dprintk_rcu("RPC: shutting down %s client for %s\n",
- clnt->cl_program->name,
- rcu_dereference(clnt->cl_xprt)->servername);
+ trace_rpc_clnt_shutdown(clnt);

while (!list_empty(&clnt->cl_tasks)) {
rpc_killall_tasks(clnt);
@@ -884,6 +877,8 @@ static void rpc_free_client_work(struct work_struct *work)
{
struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);

+ trace_rpc_clnt_free(clnt);
+
/* These might block on processes that might allocate memory,
* so they cannot be called in rpciod, so they are handled separately
* here.
@@ -899,9 +894,7 @@ static void rpc_free_client_work(struct work_struct *work)
{
struct rpc_clnt *parent = NULL;

- dprintk_rcu("RPC: destroying %s client for %s\n",
- clnt->cl_program->name,
- rcu_dereference(clnt->cl_xprt)->servername);
+ trace_rpc_clnt_release(clnt);
if (clnt->cl_parent != clnt)
parent = clnt->cl_parent;
rpc_unregister_client(clnt);
@@ -945,8 +938,6 @@ static void rpc_free_client_work(struct work_struct *work)
void
rpc_release_client(struct rpc_clnt *clnt)
{
- dprintk("RPC: rpc_release_client(%p)\n", clnt);
-
do {
if (list_empty(&clnt->cl_tasks))
wake_up(&destroy_wait);