Commit 842af315 authored by Ingo Molnar's avatar Ingo Molnar Committed by Thomas Gleixner
Browse files

ftrace: sysprof plugin improvement 



add sample maximum depth.

Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent a6dd24f8

kernel/trace/trace_sysprof.c

+3 −6
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ static int __read_mostly tracer_enabled; 
 * 10 msecs for now:

 */

static const unsigned long sample_period = 1000000;

static const unsigned int sample_max_depth = 512;



/*

 * Per CPU hrtimers that do the profiling:
@@ -45,8 +46,6 @@ static int copy_stack_frame(const void __user *fp, struct stack_frame *frame) 
	return 1;

}



#define SYSPROF_MAX_ADDRESSES	512



static void timer_notify(struct pt_regs *regs, int cpu)

{

	const void __user *frame_pointer;
@@ -80,7 +79,7 @@ static void timer_notify(struct pt_regs *regs, int cpu) 


	frame_pointer = (void __user *)regs->bp;



	for (i = 0; i < SYSPROF_MAX_ADDRESSES; i++) {

	for (i = 0; i < sample_max_depth; i++) {

		if (!copy_stack_frame(frame_pointer, &frame))

			break;

		if ((unsigned long)frame_pointer < regs->sp)
@@ -93,7 +92,7 @@ static void timer_notify(struct pt_regs *regs, int cpu) 


	trace_special(tr, data, 2, current->pid, i);



	if (i == SYSPROF_MAX_ADDRESSES)

	if (i == sample_max_depth)

		trace_special(tr, data, -1, -1, -1);

}
@@ -126,7 +125,6 @@ static void start_stack_timers(void) 
	for_each_online_cpu(cpu) {

		set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));

		start_stack_timer(cpu);

		printk(KERN_INFO "started sysprof timer on cpu%d\n", cpu);

	}

	set_cpus_allowed_ptr(current, &saved_mask);

}
@@ -136,7 +134,6 @@ static void stop_stack_timer(int cpu) 
	struct hrtimer *hrtimer = &per_cpu(stack_trace_hrtimer, cpu);



	hrtimer_cancel(hrtimer);

	printk(KERN_INFO "cancelled sysprof timer on cpu%d\n", cpu);

}



static void stop_stack_timers(void)