[PATCH net-next 1/4] afs: Add some tracepoints

From: David Howells
Date: Mon Jan 09 2017 - 09:54:31 EST


Add three tracepoints to the AFS filesystem:

(1) The afs_recv_data tracepoint logs data segments that are extracted
from the data received from the peer through afs_extract_data().

(2) The afs_notify_call tracepoint logs notification from AF_RXRPC of data
coming in to an asynchronous call.

(3) The afs_cb_call tracepoint logs incoming calls that have had their
operation ID extracted and mapped into a supported cache manager
service call.

To make (3) work, the name strings in the afs_call_type struct objects have
to be annotated with __tracepoint_string. This is done with the CM_NAME()
macro.

Further, the AFS call state enum needs a name so that it can be used to
declare parameter types.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

fs/afs/cmservice.c | 22 ++++++---
fs/afs/internal.h | 21 +++++---
fs/afs/main.c | 1
fs/afs/rxrpc.c | 6 ++
include/trace/events/afs.h | 109 ++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 144 insertions(+), 15 deletions(-)
create mode 100644 include/trace/events/afs.h

diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c
index d764236072b1..a2e1e02005f6 100644
--- a/fs/afs/cmservice.c
+++ b/fs/afs/cmservice.c
@@ -25,11 +25,16 @@ static int afs_deliver_cb_probe_uuid(struct afs_call *);
static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *);
static void afs_cm_destructor(struct afs_call *);

+#define CM_NAME(name) \
+ const char afs_SRXCB##name##_name[] __tracepoint_string = \
+ "CB." #name
+
/*
* CB.CallBack operation type
*/
+static CM_NAME(CallBack);
static const struct afs_call_type afs_SRXCBCallBack = {
- .name = "CB.CallBack",
+ .name = afs_SRXCBCallBack_name,
.deliver = afs_deliver_cb_callback,
.abort_to_error = afs_abort_to_error,
.destructor = afs_cm_destructor,
@@ -38,8 +43,9 @@ static const struct afs_call_type afs_SRXCBCallBack = {
/*
* CB.InitCallBackState operation type
*/
+static CM_NAME(InitCallBackState);
static const struct afs_call_type afs_SRXCBInitCallBackState = {
- .name = "CB.InitCallBackState",
+ .name = afs_SRXCBInitCallBackState_name,
.deliver = afs_deliver_cb_init_call_back_state,
.abort_to_error = afs_abort_to_error,
.destructor = afs_cm_destructor,
@@ -48,8 +54,9 @@ static const struct afs_call_type afs_SRXCBInitCallBackState = {
/*
* CB.InitCallBackState3 operation type
*/
+static CM_NAME(InitCallBackState3);
static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
- .name = "CB.InitCallBackState3",
+ .name = afs_SRXCBInitCallBackState3_name,
.deliver = afs_deliver_cb_init_call_back_state3,
.abort_to_error = afs_abort_to_error,
.destructor = afs_cm_destructor,
@@ -58,8 +65,9 @@ static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
/*
* CB.Probe operation type
*/
+static CM_NAME(Probe);
static const struct afs_call_type afs_SRXCBProbe = {
- .name = "CB.Probe",
+ .name = afs_SRXCBProbe_name,
.deliver = afs_deliver_cb_probe,
.abort_to_error = afs_abort_to_error,
.destructor = afs_cm_destructor,
@@ -68,8 +76,9 @@ static const struct afs_call_type afs_SRXCBProbe = {
/*
* CB.ProbeUuid operation type
*/
+static CM_NAME(ProbeUuid);
static const struct afs_call_type afs_SRXCBProbeUuid = {
- .name = "CB.ProbeUuid",
+ .name = afs_SRXCBProbeUuid_name,
.deliver = afs_deliver_cb_probe_uuid,
.abort_to_error = afs_abort_to_error,
.destructor = afs_cm_destructor,
@@ -78,8 +87,9 @@ static const struct afs_call_type afs_SRXCBProbeUuid = {
/*
* CB.TellMeAboutYourself operation type
*/
+static CM_NAME(TellMeAboutYourself);
static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
- .name = "CB.TellMeAboutYourself",
+ .name = afs_SRXCBTellMeAboutYourself_name,
.deliver = afs_deliver_cb_tell_me_about_yourself,
.abort_to_error = afs_abort_to_error,
.destructor = afs_cm_destructor,
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 6f7a9638ba1a..f71e58fcc2f2 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -68,6 +68,15 @@ struct afs_wait_mode {
extern const struct afs_wait_mode afs_sync_call;
extern const struct afs_wait_mode afs_async_call;

+enum afs_call_state {
+ AFS_CALL_REQUESTING, /* request is being sent for outgoing call */
+ AFS_CALL_AWAIT_REPLY, /* awaiting reply to outgoing call */
+ AFS_CALL_AWAIT_OP_ID, /* awaiting op ID on incoming call */
+ AFS_CALL_AWAIT_REQUEST, /* awaiting request data on incoming call */
+ AFS_CALL_REPLYING, /* replying to incoming call */
+ AFS_CALL_AWAIT_ACK, /* awaiting final ACK of incoming call */
+ AFS_CALL_COMPLETE, /* Completed or failed */
+};
/*
* a record of an in-progress RxRPC call
*/
@@ -91,15 +100,7 @@ struct afs_call {
pgoff_t first; /* first page in mapping to deal with */
pgoff_t last; /* last page in mapping to deal with */
size_t offset; /* offset into received data store */
- enum { /* call state */
- AFS_CALL_REQUESTING, /* request is being sent for outgoing call */
- AFS_CALL_AWAIT_REPLY, /* awaiting reply to outgoing call */
- AFS_CALL_AWAIT_OP_ID, /* awaiting op ID on incoming call */
- AFS_CALL_AWAIT_REQUEST, /* awaiting request data on incoming call */
- AFS_CALL_REPLYING, /* replying to incoming call */
- AFS_CALL_AWAIT_ACK, /* awaiting final ACK of incoming call */
- AFS_CALL_COMPLETE, /* Completed or failed */
- } state;
+ enum afs_call_state state;
int error; /* error code */
u32 abort_code; /* Remote abort ID or 0 */
unsigned request_size; /* size of request data */
@@ -773,6 +774,8 @@ extern int afs_fsync(struct file *, loff_t, loff_t, int);
/*
* debug tracing
*/
+#include <trace/events/afs.h>
+
extern unsigned afs_debug;

#define dbgprintk(FMT,...) \
diff --git a/fs/afs/main.c b/fs/afs/main.c
index 0b187ef3b5b7..f8188feb03ad 100644
--- a/fs/afs/main.c
+++ b/fs/afs/main.c
@@ -15,6 +15,7 @@
#include <linux/completion.h>
#include <linux/sched.h>
#include <linux/random.h>
+#define CREATE_TRACE_POINTS
#include "internal.h"

MODULE_DESCRIPTION("AFS Client File System");
diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index 25f05a8d21b1..f26344a8c029 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -416,6 +416,8 @@ static void afs_deliver_to_call(struct afs_call *call)
ret = rxrpc_kernel_recv_data(afs_socket, call->rxcall,
NULL, 0, &offset, false,
&call->abort_code);
+ trace_afs_recv_data(call, 0, offset, false, ret);
+
if (ret == -EINPROGRESS || ret == -EAGAIN)
return;
if (ret == 1 || ret < 0) {
@@ -541,6 +543,7 @@ static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall,
{
struct afs_call *call = (struct afs_call *)call_user_ID;

+ trace_afs_notify_call(rxcall, call);
call->need_attention = true;
queue_work(afs_async_calls, &call->async_work);
}
@@ -689,6 +692,8 @@ static int afs_deliver_cm_op_id(struct afs_call *call)
if (!afs_cm_incoming_call(call))
return -ENOTSUPP;

+ trace_afs_cb_call(call);
+
/* pass responsibility for the remainer of this message off to the
* cache manager op */
return call->type->deliver(call);
@@ -780,6 +785,7 @@ int afs_extract_data(struct afs_call *call, void *buf, size_t count,
ret = rxrpc_kernel_recv_data(afs_socket, call->rxcall,
buf, count, &call->offset,
want_more, &call->abort_code);
+ trace_afs_recv_data(call, count, call->offset, want_more, ret);
if (ret == 0 || ret == -EAGAIN)
return ret;

diff --git a/include/trace/events/afs.h b/include/trace/events/afs.h
new file mode 100644
index 000000000000..845907b04ff4
--- /dev/null
+++ b/include/trace/events/afs.h
@@ -0,0 +1,109 @@
+/* AFS tracepoints
+ *
+ * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@xxxxxxxxxx)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM afs
+
+#if !defined(_TRACE_AFS_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_AFS_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(afs_recv_data,
+ TP_PROTO(struct afs_call *call, unsigned count, unsigned offset,
+ bool want_more, int ret),
+
+ TP_ARGS(call, count, offset, want_more, ret),
+
+ TP_STRUCT__entry(
+ __field(struct rxrpc_call *, rxcall )
+ __field(struct afs_call *, call )
+ __field(enum afs_call_state, state )
+ __field(unsigned int, count )
+ __field(unsigned int, offset )
+ __field(unsigned short, unmarshall )
+ __field(bool, want_more )
+ __field(int, ret )
+ ),
+
+ TP_fast_assign(
+ __entry->rxcall = call->rxcall;
+ __entry->call = call;
+ __entry->state = call->state;
+ __entry->unmarshall = call->unmarshall;
+ __entry->count = count;
+ __entry->offset = offset;
+ __entry->want_more = want_more;
+ __entry->ret = ret;
+ ),
+
+ TP_printk("c=%p ac=%p s=%u u=%u %u/%u wm=%u ret=%d",
+ __entry->rxcall,
+ __entry->call,
+ __entry->state, __entry->unmarshall,
+ __entry->offset, __entry->count,
+ __entry->want_more, __entry->ret)
+ );
+
+TRACE_EVENT(afs_notify_call,
+ TP_PROTO(struct rxrpc_call *rxcall, struct afs_call *call),
+
+ TP_ARGS(rxcall, call),
+
+ TP_STRUCT__entry(
+ __field(struct rxrpc_call *, rxcall )
+ __field(struct afs_call *, call )
+ __field(enum afs_call_state, state )
+ __field(unsigned short, unmarshall )
+ ),
+
+ TP_fast_assign(
+ __entry->rxcall = rxcall;
+ __entry->call = call;
+ __entry->state = call->state;
+ __entry->unmarshall = call->unmarshall;
+ ),
+
+ TP_printk("c=%p ac=%p s=%u u=%u",
+ __entry->rxcall,
+ __entry->call,
+ __entry->state, __entry->unmarshall)
+ );
+
+TRACE_EVENT(afs_cb_call,
+ TP_PROTO(struct afs_call *call),
+
+ TP_ARGS(call),
+
+ TP_STRUCT__entry(
+ __field(struct rxrpc_call *, rxcall )
+ __field(struct afs_call *, call )
+ __field(const char *, name )
+ __field(u32, op )
+ ),
+
+ TP_fast_assign(
+ __entry->rxcall = call->rxcall;
+ __entry->call = call;
+ __entry->name = call->type->name;
+ __entry->op = call->operation_ID;
+ ),
+
+ TP_printk("c=%p ac=%p %s o=%u",
+ __entry->rxcall,
+ __entry->call,
+ __entry->name,
+ __entry->op)
+ );
+
+#endif /* _TRACE_AFS_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>