[for-next][PATCH 32/33] tracing/ftrace: Allow for the traceonoff probe be unique to instances

From: Steven Rostedt
Date: Fri Apr 21 2017 - 17:36:57 EST


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

Have the traceon/off function probe triggers affect only the instance they
are set in. This required making the trace_on/off accessible for other files
in the tracing directory.

Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
kernel/trace/trace.c | 4 ++--
kernel/trace/trace.h | 2 ++
kernel/trace/trace_functions.c | 21 +++++++++++----------
3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 57e9c546bebb..60c904fa5480 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -757,7 +757,7 @@ __trace_buffer_lock_reserve(struct ring_buffer *buffer,
return event;
}

-static void tracer_tracing_on(struct trace_array *tr)
+void tracer_tracing_on(struct trace_array *tr)
{
if (tr->trace_buffer.buffer)
ring_buffer_record_on(tr->trace_buffer.buffer);
@@ -1045,7 +1045,7 @@ void tracing_snapshot_alloc(void)
EXPORT_SYMBOL_GPL(tracing_snapshot_alloc);
#endif /* CONFIG_TRACER_SNAPSHOT */

-static void tracer_tracing_off(struct trace_array *tr)
+void tracer_tracing_off(struct trace_array *tr)
{
if (tr->trace_buffer.buffer)
ring_buffer_record_off(tr->trace_buffer.buffer);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 8f6754fba778..bc011c1f3d71 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -582,6 +582,8 @@ void tracing_reset_all_online_cpus(void);
int tracing_open_generic(struct inode *inode, struct file *filp);
bool tracing_is_disabled(void);
int tracer_tracing_is_on(struct trace_array *tr);
+void tracer_tracing_on(struct trace_array *tr);
+void tracer_tracing_off(struct trace_array *tr);
struct dentry *trace_create_file(const char *name,
umode_t mode,
struct dentry *parent,
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 7775e1ca5bad..8c30ca733a5c 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -268,7 +268,8 @@ static struct tracer function_trace __tracer_data =

#ifdef CONFIG_DYNAMIC_FTRACE
static void update_traceon_count(struct ftrace_probe_ops *ops,
- unsigned long ip, bool on,
+ unsigned long ip,
+ struct trace_array *tr, bool on,
void *data)
{
struct ftrace_func_mapper *mapper = data;
@@ -313,13 +314,13 @@ static void update_traceon_count(struct ftrace_probe_ops *ops,
/* Make sure we see count before checking tracing state */
smp_rmb();

- if (on == !!tracing_is_on())
+ if (on == !!tracer_tracing_is_on(tr))
return;

if (on)
- tracing_on();
+ tracer_tracing_on(tr);
else
- tracing_off();
+ tracer_tracing_off(tr);

/* Make sure tracing state is visible before updating count */
smp_wmb();
@@ -332,7 +333,7 @@ ftrace_traceon_count(unsigned long ip, unsigned long parent_ip,
struct trace_array *tr, struct ftrace_probe_ops *ops,
void *data)
{
- update_traceon_count(ops, ip, 1, data);
+ update_traceon_count(ops, ip, tr, 1, data);
}

static void
@@ -340,7 +341,7 @@ ftrace_traceoff_count(unsigned long ip, unsigned long parent_ip,
struct trace_array *tr, struct ftrace_probe_ops *ops,
void *data)
{
- update_traceon_count(ops, ip, 0, data);
+ update_traceon_count(ops, ip, tr, 0, data);
}

static void
@@ -348,10 +349,10 @@ ftrace_traceon(unsigned long ip, unsigned long parent_ip,
struct trace_array *tr, struct ftrace_probe_ops *ops,
void *data)
{
- if (tracing_is_on())
+ if (tracer_tracing_is_on(tr))
return;

- tracing_on();
+ tracer_tracing_on(tr);
}

static void
@@ -359,10 +360,10 @@ ftrace_traceoff(unsigned long ip, unsigned long parent_ip,
struct trace_array *tr, struct ftrace_probe_ops *ops,
void *data)
{
- if (!tracing_is_on())
+ if (!tracer_tracing_is_on(tr))
return;

- tracing_off();
+ tracer_tracing_off(tr);
}

/*
--
2.10.2