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-rw-r--r--kernel/trace/trace_functions.c116
1 files changed, 76 insertions, 40 deletions
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 85e517e84f50..3f8dc1ce8b9c 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -13,33 +13,83 @@
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>
+#include <linux/slab.h>
#include <linux/fs.h>
#include "trace.h"
-/* function tracing enabled */
-static int ftrace_function_enabled;
+static void tracing_start_function_trace(struct trace_array *tr);
+static void tracing_stop_function_trace(struct trace_array *tr);
+static void
+function_trace_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs);
+static void
+function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs);
+static struct ftrace_ops trace_ops;
+static struct ftrace_ops trace_stack_ops;
+static struct tracer_flags func_flags;
+
+/* Our option */
+enum {
+ TRACE_FUNC_OPT_STACK = 0x1,
+};
+
+static int allocate_ftrace_ops(struct trace_array *tr)
+{
+ struct ftrace_ops *ops;
-static struct trace_array *func_trace;
+ ops = kzalloc(sizeof(*ops), GFP_KERNEL);
+ if (!ops)
+ return -ENOMEM;
-static void tracing_start_function_trace(void);
-static void tracing_stop_function_trace(void);
+ /* Currently only the non stack verision is supported */
+ ops->func = function_trace_call;
+ ops->flags = FTRACE_OPS_FL_RECURSION_SAFE;
+
+ tr->ops = ops;
+ ops->private = tr;
+ return 0;
+}
static int function_trace_init(struct trace_array *tr)
{
- func_trace = tr;
+ struct ftrace_ops *ops;
+ int ret;
+
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL) {
+ /* There's only one global tr */
+ if (!trace_ops.private) {
+ trace_ops.private = tr;
+ trace_stack_ops.private = tr;
+ }
+
+ if (func_flags.val & TRACE_FUNC_OPT_STACK)
+ ops = &trace_stack_ops;
+ else
+ ops = &trace_ops;
+ tr->ops = ops;
+ } else {
+ ret = allocate_ftrace_ops(tr);
+ if (ret)
+ return ret;
+ }
+
tr->trace_buffer.cpu = get_cpu();
put_cpu();
tracing_start_cmdline_record();
- tracing_start_function_trace();
+ tracing_start_function_trace(tr);
return 0;
}
static void function_trace_reset(struct trace_array *tr)
{
- tracing_stop_function_trace();
+ tracing_stop_function_trace(tr);
tracing_stop_cmdline_record();
+ if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL))
+ kfree(tr->ops);
+ tr->ops = NULL;
}
static void function_trace_start(struct trace_array *tr)
@@ -47,25 +97,18 @@ static void function_trace_start(struct trace_array *tr)
tracing_reset_online_cpus(&tr->trace_buffer);
}
-/* Our option */
-enum {
- TRACE_FUNC_OPT_STACK = 0x1,
-};
-
-static struct tracer_flags func_flags;
-
static void
function_trace_call(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *pt_regs)
{
- struct trace_array *tr = func_trace;
+ struct trace_array *tr = op->private;
struct trace_array_cpu *data;
unsigned long flags;
int bit;
int cpu;
int pc;
- if (unlikely(!ftrace_function_enabled))
+ if (unlikely(!tr->function_enabled))
return;
pc = preempt_count();
@@ -91,14 +134,14 @@ static void
function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *pt_regs)
{
- struct trace_array *tr = func_trace;
+ struct trace_array *tr = op->private;
struct trace_array_cpu *data;
unsigned long flags;
long disabled;
int cpu;
int pc;
- if (unlikely(!ftrace_function_enabled))
+ if (unlikely(!tr->function_enabled))
return;
/*
@@ -128,7 +171,6 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
local_irq_restore(flags);
}
-
static struct ftrace_ops trace_ops __read_mostly =
{
.func = function_trace_call,
@@ -153,26 +195,17 @@ static struct tracer_flags func_flags = {
.opts = func_opts
};
-static void tracing_start_function_trace(void)
+static void tracing_start_function_trace(struct trace_array *tr)
{
- ftrace_function_enabled = 0;
-
- if (func_flags.val & TRACE_FUNC_OPT_STACK)
- register_ftrace_function(&trace_stack_ops);
- else
- register_ftrace_function(&trace_ops);
-
- ftrace_function_enabled = 1;
+ tr->function_enabled = 0;
+ register_ftrace_function(tr->ops);
+ tr->function_enabled = 1;
}
-static void tracing_stop_function_trace(void)
+static void tracing_stop_function_trace(struct trace_array *tr)
{
- ftrace_function_enabled = 0;
-
- if (func_flags.val & TRACE_FUNC_OPT_STACK)
- unregister_ftrace_function(&trace_stack_ops);
- else
- unregister_ftrace_function(&trace_ops);
+ tr->function_enabled = 0;
+ unregister_ftrace_function(tr->ops);
}
static int
@@ -184,12 +217,14 @@ func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
if (!!set == !!(func_flags.val & TRACE_FUNC_OPT_STACK))
break;
+ unregister_ftrace_function(tr->ops);
+
if (set) {
- unregister_ftrace_function(&trace_ops);
- register_ftrace_function(&trace_stack_ops);
+ tr->ops = &trace_stack_ops;
+ register_ftrace_function(tr->ops);
} else {
- unregister_ftrace_function(&trace_stack_ops);
- register_ftrace_function(&trace_ops);
+ tr->ops = &trace_ops;
+ register_ftrace_function(tr->ops);
}
break;
@@ -209,6 +244,7 @@ static struct tracer function_trace __tracer_data =
.wait_pipe = poll_wait_pipe,
.flags = &func_flags,
.set_flag = func_set_flag,
+ .allow_instances = true,
#ifdef CONFIG_FTRACE_SELFTEST
.selftest = trace_selftest_startup_function,
#endif
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