[for-next][PATCH 13/33] ftrace: Pass probe ops to probe function

From: Steven Rostedt
Date: Fri Apr 21 2017 - 17:40:37 EST


From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>

In preparation to cleaning up the probe function registration code, the
"data" parameter will eventually be removed from the probe->func() call.
Instead it will receive its own "ops" function, in which it can set up its
own data that it needs to map.

Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
kernel/trace/ftrace.c | 2 +-
kernel/trace/trace.c | 6 ++++--
kernel/trace/trace.h | 1 +
kernel/trace/trace_events.c | 8 +++++---
kernel/trace/trace_functions.c | 24 ++++++++++++++++--------
5 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index b6dc29583c86..d8873079bed4 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3739,7 +3739,7 @@ static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip,
preempt_disable_notrace();
hlist_for_each_entry_rcu_notrace(entry, hhd, node) {
if (entry->ip == ip)
- entry->ops->func(ip, parent_ip, &entry->data);
+ entry->ops->func(ip, parent_ip, entry->ops, &entry->data);
}
preempt_enable_notrace();
}
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8a5064a03ddf..41e9a20f91f0 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6735,13 +6735,15 @@ static const struct file_operations tracing_dyn_info_fops = {

#if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE)
static void
-ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_snapshot(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
tracing_snapshot();
}

static void
-ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
unsigned long *count = (long *)data;

diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index a63411c53c5e..0f915c264c19 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -934,6 +934,7 @@ static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) {
struct ftrace_probe_ops {
void (*func)(unsigned long ip,
unsigned long parent_ip,
+ struct ftrace_probe_ops *ops,
void **data);
int (*init)(struct ftrace_probe_ops *ops,
unsigned long ip, void **data);
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 93116549a284..9dbac1881b03 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2461,7 +2461,8 @@ struct event_probe_data {
};

static void
-event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data)
+event_enable_probe(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **_data)
{
struct event_probe_data **pdata = (struct event_probe_data **)_data;
struct event_probe_data *data = *pdata;
@@ -2476,7 +2477,8 @@ event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data)
}

static void
-event_enable_count_probe(unsigned long ip, unsigned long parent_ip, void **_data)
+event_enable_count_probe(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **_data)
{
struct event_probe_data **pdata = (struct event_probe_data **)_data;
struct event_probe_data *data = *pdata;
@@ -2494,7 +2496,7 @@ event_enable_count_probe(unsigned long ip, unsigned long parent_ip, void **_data
if (data->count != -1)
(data->count)--;

- event_enable_probe(ip, parent_ip, _data);
+ event_enable_probe(ip, parent_ip, ops, _data);
}

static int
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 4199ca61b0e5..b99f6231281e 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -326,19 +326,22 @@ static void update_traceon_count(void **data, bool on)
}

static void
-ftrace_traceon_count(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_traceon_count(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
update_traceon_count(data, 1);
}

static void
-ftrace_traceoff_count(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_traceoff_count(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
update_traceon_count(data, 0);
}

static void
-ftrace_traceon(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_traceon(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
if (tracing_is_on())
return;
@@ -347,7 +350,8 @@ ftrace_traceon(unsigned long ip, unsigned long parent_ip, void **data)
}

static void
-ftrace_traceoff(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_traceoff(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
if (!tracing_is_on())
return;
@@ -365,13 +369,15 @@ ftrace_traceoff(unsigned long ip, unsigned long parent_ip, void **data)
#define STACK_SKIP 4

static void
-ftrace_stacktrace(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_stacktrace(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
trace_dump_stack(STACK_SKIP);
}

static void
-ftrace_stacktrace_count(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_stacktrace_count(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
long *count = (long *)data;
long old_count;
@@ -419,7 +425,8 @@ static int update_count(void **data)
}

static void
-ftrace_dump_probe(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_dump_probe(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
if (update_count(data))
ftrace_dump(DUMP_ALL);
@@ -427,7 +434,8 @@ ftrace_dump_probe(unsigned long ip, unsigned long parent_ip, void **data)

/* Only dump the current CPU buffer. */
static void
-ftrace_cpudump_probe(unsigned long ip, unsigned long parent_ip, void **data)
+ftrace_cpudump_probe(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_probe_ops *ops, void **data)
{
if (update_count(data))
ftrace_dump(DUMP_ORIG);
--
2.10.2