dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

ftrace: extend sysprof plugin some more 

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Ingo Molnar 2008-05-12 21:20:47 +02:00 committed by Thomas Gleixner
parent 0075fa8030
commit 56a08bdcff
1 changed files with 76 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

80
kernel/trace/trace_sysprof.c
View File

@ -3,7 +3,7 @@
*
* Copyright (C) 2007 Steven Rostedt <srostedt@redhat.com>
* Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
*
* Copyright (C) 2004, 2005, Soeren Sandmann
*/
#include <linux/kallsyms.h>
#include <linux/debugfs.h>
@ -11,13 +11,17 @@
#include <linux/uaccess.h>
#include <linux/ftrace.h>
#include <linux/module.h>
#include <linux/irq.h>
#include <linux/fs.h>
#include "trace.h"
static struct trace_array *ctx_trace;
static struct trace_array *sysprof_trace;
static int __read_mostly tracer_enabled;
/*
* 10 msecs for now:
*/
static const unsigned long sample_period = 1000000;
/*
@ -25,10 +29,78 @@ static const unsigned long sample_period = 1000000;
*/
static DEFINE_PER_CPU(struct hrtimer, stack_trace_hrtimer);
struct stack_frame {
const void __user *next_fp;
unsigned long return_address;
};
static int copy_stack_frame(const void __user *fp, struct stack_frame *frame)
{
if (!access_ok(VERIFY_READ, fp, sizeof(*frame)))
return 0;
if (__copy_from_user_inatomic(frame, frame_pointer, sizeof(*frame)))
return 0;
return 1;
}
#define SYSPROF_MAX_ADDRESSES 512
static void timer_notify(struct pt_regs *regs, int cpu)
{
const void __user *frame_pointer;
struct trace_array_cpu *data;
struct stack_frame frame;
struct trace_array *tr;
int is_user;
int i;
if (!regs)
return;
tr = sysprof_trace;
data = tr->data[cpu];
is_user = user_mode(regs);
if (!current || current->pid == 0)
return;
if (is_user && current->state != TASK_RUNNING)
return;
if (!is_user) {
/* kernel */
ftrace(tr, data, current->pid, 1, 0);
return;
}
trace_special(tr, data, 0, current->pid, regs->ip);
frame_pointer = (void __user *)regs->bp;
for (i = 0; i < SYSPROF_MAX_ADDRESSES; i++) {
if (!copy_stack_frame(frame_pointer, &frame))
break;
if ((unsigned long)frame_pointer < regs->sp)
break;
trace_special(tr, data, 1, frame.return_address,
(unsigned long)frame_pointer);
frame_pointer = frame.next_fp;
}
trace_special(tr, data, 2, current->pid, i);
if (i == SYSPROF_MAX_ADDRESSES)
trace_special(tr, data, -1, -1, -1);
}
static enum hrtimer_restart stack_trace_timer_fn(struct hrtimer *hrtimer)
{
/* trace here */
panic_timeout++;
timer_notify(get_irq_regs(), smp_processor_id());
hrtimer_forward_now(hrtimer, ns_to_ktime(sample_period));
@ -100,7 +172,7 @@ static notrace void stop_stack_trace(struct trace_array *tr)
static notrace void stack_trace_init(struct trace_array *tr)
{
ctx_trace = tr;
sysprof_trace = tr;
if (tr->ctrl)
start_stack_trace(tr);