a4e0591ece
Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Since the online target runs always on the target CPU we can drop smp_call_function_single(). The functions is invoked with interrupts off to keep the old calling convention. If the maintainer things that this function can be called with interrupts enabled then it can be removed :) Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Robert Richter <rric@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: oprofile-list@lists.sf.net Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160906170457.32393-10-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
122 lines
2.5 KiB
C
122 lines
2.5 KiB
C
/**
|
|
* @file timer_int.c
|
|
*
|
|
* @remark Copyright 2002 OProfile authors
|
|
* @remark Read the file COPYING
|
|
*
|
|
* @author John Levon <levon@movementarian.org>
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/notifier.h>
|
|
#include <linux/smp.h>
|
|
#include <linux/oprofile.h>
|
|
#include <linux/profile.h>
|
|
#include <linux/init.h>
|
|
#include <linux/cpu.h>
|
|
#include <linux/hrtimer.h>
|
|
#include <asm/irq_regs.h>
|
|
#include <asm/ptrace.h>
|
|
|
|
#include "oprof.h"
|
|
|
|
static DEFINE_PER_CPU(struct hrtimer, oprofile_hrtimer);
|
|
static int ctr_running;
|
|
|
|
static enum hrtimer_restart oprofile_hrtimer_notify(struct hrtimer *hrtimer)
|
|
{
|
|
oprofile_add_sample(get_irq_regs(), 0);
|
|
hrtimer_forward_now(hrtimer, ns_to_ktime(TICK_NSEC));
|
|
return HRTIMER_RESTART;
|
|
}
|
|
|
|
static void __oprofile_hrtimer_start(void *unused)
|
|
{
|
|
struct hrtimer *hrtimer = this_cpu_ptr(&oprofile_hrtimer);
|
|
|
|
if (!ctr_running)
|
|
return;
|
|
|
|
hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
|
|
hrtimer->function = oprofile_hrtimer_notify;
|
|
|
|
hrtimer_start(hrtimer, ns_to_ktime(TICK_NSEC),
|
|
HRTIMER_MODE_REL_PINNED);
|
|
}
|
|
|
|
static int oprofile_hrtimer_start(void)
|
|
{
|
|
get_online_cpus();
|
|
ctr_running = 1;
|
|
on_each_cpu(__oprofile_hrtimer_start, NULL, 1);
|
|
put_online_cpus();
|
|
return 0;
|
|
}
|
|
|
|
static void __oprofile_hrtimer_stop(int cpu)
|
|
{
|
|
struct hrtimer *hrtimer = &per_cpu(oprofile_hrtimer, cpu);
|
|
|
|
if (!ctr_running)
|
|
return;
|
|
|
|
hrtimer_cancel(hrtimer);
|
|
}
|
|
|
|
static void oprofile_hrtimer_stop(void)
|
|
{
|
|
int cpu;
|
|
|
|
get_online_cpus();
|
|
for_each_online_cpu(cpu)
|
|
__oprofile_hrtimer_stop(cpu);
|
|
ctr_running = 0;
|
|
put_online_cpus();
|
|
}
|
|
|
|
static int oprofile_timer_online(unsigned int cpu)
|
|
{
|
|
local_irq_disable();
|
|
__oprofile_hrtimer_start(NULL);
|
|
local_irq_enable();
|
|
return 0;
|
|
}
|
|
|
|
static int oprofile_timer_prep_down(unsigned int cpu)
|
|
{
|
|
__oprofile_hrtimer_stop(cpu);
|
|
return 0;
|
|
}
|
|
|
|
static enum cpuhp_state hp_online;
|
|
|
|
static int oprofile_hrtimer_setup(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
|
|
"oprofile/timer:online",
|
|
oprofile_timer_online,
|
|
oprofile_timer_prep_down);
|
|
if (ret < 0)
|
|
return ret;
|
|
hp_online = ret;
|
|
return 0;
|
|
}
|
|
|
|
static void oprofile_hrtimer_shutdown(void)
|
|
{
|
|
cpuhp_remove_state_nocalls(hp_online);
|
|
}
|
|
|
|
int oprofile_timer_init(struct oprofile_operations *ops)
|
|
{
|
|
ops->create_files = NULL;
|
|
ops->setup = oprofile_hrtimer_setup;
|
|
ops->shutdown = oprofile_hrtimer_shutdown;
|
|
ops->start = oprofile_hrtimer_start;
|
|
ops->stop = oprofile_hrtimer_stop;
|
|
ops->cpu_type = "timer";
|
|
printk(KERN_INFO "oprofile: using timer interrupt.\n");
|
|
return 0;
|
|
}
|