Commit fed4d7bd authored by John Levon's avatar John Levon Committed by Linus Torvalds

[PATCH] OProfile: timer usage override

A patch mostly by Will Cohen, adding a parameter to OProfile to
over-ride use of the perfctr hardware. Useful for testing and
a host of other things.
parent 0d22b578
......@@ -652,6 +652,9 @@ running once the system is up.
opl3sa2= [HW,OSS]
Format: <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
oprofile.timer= [HW]
Use timer interrupt instead of performance counters
optcd= [HW,CD]
Format: <io>
......
......@@ -11,6 +11,7 @@
#include <linux/module.h>
#include <linux/init.h>
#include <linux/oprofile.h>
#include <linux/moduleparam.h>
#include <asm/semaphore.h>
#include "oprof.h"
......@@ -24,6 +25,12 @@ unsigned long oprofile_started;
static unsigned long is_setup;
static DECLARE_MUTEX(start_sem);
/* timer
0 - use performance monitoring hardware if available
1 - use the timer int mechanism regardless
*/
static int timer = 0;
int oprofile_setup(void)
{
int err;
......@@ -124,13 +131,16 @@ extern void timer_init(struct oprofile_operations ** ops);
static int __init oprofile_init(void)
{
int err;
int err = -ENODEV;
if (!timer) {
/* Architecture must fill in the interrupt ops and the
* logical CPU type, or we can fall back to the timer
* interrupt profiler.
*/
err = oprofile_arch_init(&oprofile_ops);
}
if (err == -ENODEV) {
timer_init(&oprofile_ops);
err = 0;
......@@ -164,6 +174,9 @@ static void __exit oprofile_exit(void)
module_init(oprofile_init);
module_exit(oprofile_exit);
module_param_named(timer, timer, int, 0644);
MODULE_PARM_DESC(timer, "force use of timer interrupt");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("John Levon <levon@movementarian.org>");
MODULE_DESCRIPTION("OProfile system profiler");
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment