xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ftrace: Remove global function list and call function directly

Browse Source 
Instead of having a list of global functions that are called,
as only one global function is allow to be enabled at a time, there's
no reason to have a list.

Instead, simply have all the users of the global ops, use the global ops
directly, instead of registering their own ftrace_ops. Just switch what
function is used before enabling the function tracer.

This removes a lot of code as well as the complexity involved with it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Red Hat)
2014-01-10 17:01:58 -05:00
committed by Steven Rostedt
parent a798c10faf
commit 4104d326b6
8 changed files with 133 additions and 221 deletions
Download Patch File Download Diff File Expand all files Collapse all files

55
kernel/trace/trace_functions.c
View File

@@ -26,8 +26,6 @@ function_trace_call(unsigned long ip, unsigned long parent_ip,
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 */
@@ -83,28 +81,24 @@ void ftrace_destroy_function_files(struct trace_array *tr)
static int function_trace_init(struct trace_array *tr)
{
struct ftrace_ops *ops;
ftrace_func_t func;
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 if (!tr->ops) {
/*
* Instance trace_arrays get their ops allocated
* at instance creation. Unless it failed
* the allocation.
*/
/*
* 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();
@@ -118,6 +112,7 @@ static void function_trace_reset(struct trace_array *tr)
{
tracing_stop_function_trace(tr);
tracing_stop_cmdline_record();
ftrace_reset_array_ops(tr);
}
static void function_trace_start(struct trace_array *tr)
@@ -199,18 +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) },
@@ -248,10 +231,10 @@ func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
unregister_ftrace_function(tr->ops);
if (set) {
tr->ops = &trace_stack_ops;
tr->ops->func = function_stack_trace_call;
register_ftrace_function(tr->ops);
} else {
tr->ops = &trace_ops;
tr->ops->func = function_trace_call;
register_ftrace_function(tr->ops);
}