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Diffstat (limited to 'kernel/trace/trace_functions.c')
-rw-r--r--kernel/trace/trace_functions.c155
1 files changed, 101 insertions, 54 deletions
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 38fe1483c50..57f0ec962d2 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -13,33 +13,106 @@
#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 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;
+
+ /* 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 void tracing_start_function_trace(void);
-static void tracing_stop_function_trace(void);
+
+int ftrace_create_function_files(struct trace_array *tr,
+ struct dentry *parent)
+{
+ int ret;
+
+ /*
+ * The top level array uses the "global_ops", and the files are
+ * created on boot up.
+ */
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL)
+ return 0;
+
+ ret = allocate_ftrace_ops(tr);
+ if (ret)
+ return ret;
+
+ ftrace_create_filter_files(tr->ops, parent);
+
+ return 0;
+}
+
+void ftrace_destroy_function_files(struct trace_array *tr)
+{
+ ftrace_destroy_filter_files(tr->ops);
+ kfree(tr->ops);
+ tr->ops = NULL;
+}
static int function_trace_init(struct trace_array *tr)
{
- func_trace = tr;
+ ftrace_func_t func;
+
+ /*
+ * Instance trace_arrays get their ops allocated
+ * at instance creation. Unless it failed
+ * the allocation.
+ */
+ if (!tr->ops)
+ return -ENOMEM;
+
+ /* Currently only the global instance can do stack tracing */
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL &&
+ func_flags.val & TRACE_FUNC_OPT_STACK)
+ func = function_stack_trace_call;
+ else
+ func = function_trace_call;
+
+ ftrace_init_array_ops(tr, func);
+
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();
+ ftrace_reset_array_ops(tr);
}
static void function_trace_start(struct trace_array *tr)
@@ -47,25 +120,18 @@ 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 +157,14 @@ 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;
/*
@@ -128,19 +194,6 @@ 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,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
-static struct ftrace_ops trace_stack_ops __read_mostly =
-{
- .func = function_stack_trace_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
static struct tracer_opt func_opts[] = {
#ifdef CONFIG_STACKTRACE
{ TRACER_OPT(func_stack_trace, TRACE_FUNC_OPT_STACK) },
@@ -153,29 +206,21 @@ 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 func_set_flag(u32 old_flags, u32 bit, int set)
+static int
+func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
{
switch (bit) {
case TRACE_FUNC_OPT_STACK:
@@ -183,12 +228,14 @@ static int func_set_flag(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->func = function_stack_trace_call;
+ register_ftrace_function(tr->ops);
} else {
- unregister_ftrace_function(&trace_stack_ops);
- register_ftrace_function(&trace_ops);
+ tr->ops->func = function_trace_call;
+ register_ftrace_function(tr->ops);
}
break;
@@ -205,9 +252,9 @@ static struct tracer function_trace __tracer_data =
.init = function_trace_init,
.reset = function_trace_reset,
.start = function_trace_start,
- .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
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-04 11:13:24 +0000