leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

tracing: Update stack trace skipping for ORC unwinder

Browse Source 
With the addition of ORC unwinder and FRAME POINTER unwinder, the stack
trace skipping requirements have changed.

I went through the tracing stack trace dumps with ORC and with frame
pointers and recalculated the proper values.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (VMware)
2018-01-23 13:25:04 -05:00
parent 6be7fa3c74
commit 2ee5b92a25
3 changed files with 70 additions and 32 deletions
Download Patch File Download Diff File Expand all files Collapse all files

51
kernel/trace/trace_functions.c
View File

@@ -154,6 +154,24 @@ function_trace_call(unsigned long ip, unsigned long parent_ip,
preempt_enable_notrace();
}
#ifdef CONFIG_UNWINDER_ORC
/*
* Skip 2:
*
* function_stack_trace_call()
* ftrace_call()
*/
#define STACK_SKIP 2
#else
/*
* Skip 3:
* __trace_stack()
* function_stack_trace_call()
* ftrace_call()
*/
#define STACK_SKIP 3
#endif
static void
function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *pt_regs)
@@ -180,15 +198,7 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
if (likely(disabled == 1)) {
pc = preempt_count();
trace_function(tr, ip, parent_ip, flags, pc);
/*
* skip over 5 funcs:
* __ftrace_trace_stack,
* __trace_stack,
* function_stack_trace_call
* ftrace_list_func
* ftrace_call
*/
__trace_stack(tr, flags, 5, pc);
__trace_stack(tr, flags, STACK_SKIP, pc);
}
atomic_dec(&data->disabled);
@@ -367,14 +377,27 @@ ftrace_traceoff(unsigned long ip, unsigned long parent_ip,
tracer_tracing_off(tr);
}
#ifdef CONFIG_UNWINDER_ORC
/*
* Skip 4:
* ftrace_stacktrace()
* Skip 3:
*
* function_trace_probe_call()
* ftrace_ops_list_func()
* ftrace_ops_assist_func()
* ftrace_call()
*/
#define STACK_SKIP 4
#define FTRACE_STACK_SKIP 3
#else
/*
* Skip 5:
*
* __trace_stack()
* ftrace_stacktrace()
* function_trace_probe_call()
* ftrace_ops_assist_func()
* ftrace_call()
*/
#define FTRACE_STACK_SKIP 5
#endif
static __always_inline void trace_stack(struct trace_array *tr)
{
@@ -384,7 +407,7 @@ static __always_inline void trace_stack(struct trace_array *tr)
local_save_flags(flags);
pc = preempt_count();
__trace_stack(tr, flags, STACK_SKIP, pc);
__trace_stack(tr, flags, FTRACE_STACK_SKIP, pc);
}
static void