static void gator_event_sampling_online_dispatch(int cpu)
{
struct perf_event * ev;
if (!event_based_sampling)
return;
#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 1, 0)
ev = per_cpu(pevent, cpu) = perf_event_create_kernel_counter(per_cpu(pevent_attr, cpu), cpu, 0, ebs_overflow_handler);
#else
ev = per_cpu(pevent, cpu) = perf_event_create_kernel_counter(per_cpu(pevent_attr, cpu), cpu, 0, ebs_overflow_handler, 0);
#endif
if (IS_ERR(ev)) {
pr_err("gator: unable to start event-based-sampling");
return;
}
if (ev->state != PERF_EVENT_STATE_ACTIVE) {
pr_err("gator: unable to start event-based-sampling");
perf_event_release_kernel(ev);
return;
}
ev->pmu->read(ev);
per_cpu(prev_value, cpu) = local64_read(&ev->count);
}
/** Initialize performance sampling
* Call this during probe initialization to set up performance event sampling
* for all online cpus. Returns non-zero on error.
*
* @param stp Handle for the event to be registered.
*/
static long _stp_perf_init (struct stap_perf_probe *stp)
{
int cpu;
/* allocate space for the event descriptor for each cpu */
stp->events = _stp_alloc_percpu (sizeof(struct perf_event*));
if (stp->events == NULL) {
return -ENOMEM;
}
/* initialize event on each processor */
stp_for_each_cpu(cpu) {
struct perf_event **event = per_cpu_ptr (stp->events, cpu);
if (cpu_is_offline(cpu)) {
*event = NULL;
continue;
}
*event = perf_event_create_kernel_counter(&stp->attr,
cpu, -1,
stp->callback);
if (IS_ERR(*event)) {
long rc = PTR_ERR(*event);
*event = NULL;
_stp_perf_del(stp);
return rc;
}
}
return 0;
}
/**
* register_user_hw_breakpoint - register a hardware breakpoint for user space
* @attr: breakpoint attributes
* @triggered: callback to trigger when we hit the breakpoint
* @tsk: pointer to 'task_struct' of the process to which the address belongs
*/
struct perf_event *
register_user_hw_breakpoint(struct perf_event_attr *attr,
perf_overflow_handler_t triggered,
struct task_struct *tsk)
{
return perf_event_create_kernel_counter(attr, -1, tsk->pid, triggered);
}
static int op_create_counter(int cpu, int event)
{
struct perf_event *pevent;
if (!counter_config[event].enabled || perf_events[cpu][event])
return 0;
pevent = perf_event_create_kernel_counter(&counter_config[event].attr,
cpu, NULL,
op_overflow_handler, NULL);
if (IS_ERR(pevent))
return PTR_ERR(pevent);
if (pevent->state != PERF_EVENT_STATE_ACTIVE) {
perf_event_release_kernel(pevent);
pr_warning("oprofile: failed to enable event %d "
"on CPU %d\n", event, cpu);
return -EBUSY;
}
perf_events[cpu][event] = pevent;
return 0;
}
static int op_create_counter(int cpu, int event)
{
int ret = 0;
struct perf_event *pevent;
if (!counter_config[event].enabled || (perf_events[cpu][event] != NULL))
return ret;
pevent = perf_event_create_kernel_counter(&counter_config[event].attr,
cpu, -1,
op_overflow_handler);
if (IS_ERR(pevent)) {
ret = PTR_ERR(pevent);
} else if (pevent->state != PERF_EVENT_STATE_ACTIVE) {
perf_event_release_kernel(pevent);
pr_warning("oprofile: failed to enable event %d "
"on CPU %d\n", event, cpu);
ret = -EBUSY;
} else {
perf_events[cpu][event] = pevent;
}
return ret;
}
static int watchdog_nmi_enable(unsigned int cpu)
{
struct perf_event_attr *wd_attr;
struct perf_event *event = per_cpu(watchdog_ev, cpu);
/* is it already setup and enabled? */
if (event && event->state > PERF_EVENT_STATE_OFF)
goto out;
/* it is setup but not enabled */
if (event != NULL)
goto out_enable;
wd_attr = &wd_hw_attr;
wd_attr->sample_period = hw_nmi_get_sample_period(watchdog_thresh);
/* Try to register using hardware perf events */
event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback, NULL);
/* save cpu0 error for future comparision */
if (cpu == 0 && IS_ERR(event))
cpu0_err = PTR_ERR(event);
if (!IS_ERR(event)) {
/* only print for cpu0 or different than cpu0 */
if (cpu == 0 || cpu0_err)
pr_info("enabled on all CPUs, permanently consumes one hw-PMU counter.\n");
goto out_save;
}
/* skip displaying the same error again */
if (cpu > 0 && (PTR_ERR(event) == cpu0_err))
return PTR_ERR(event);
/* vary the KERN level based on the returned errno */
if (PTR_ERR(event) == -EOPNOTSUPP)
pr_info("disabled (cpu%i): not supported (no LAPIC?)\n", cpu);
else if (PTR_ERR(event) == -ENOENT)
pr_warning("disabled (cpu%i): hardware events not enabled\n",
cpu);
else
pr_err("disabled (cpu%i): unable to create perf event: %ld\n",
cpu, PTR_ERR(event));
return PTR_ERR(event);
/* success path */
out_save:
per_cpu(watchdog_ev, cpu) = event;
out_enable:
perf_event_enable(per_cpu(watchdog_ev, cpu));
out:
return 0;
}
void fn (void) {
struct perf_event_attr *attr = NULL;
int cpu = 0;
struct task_struct *tsk = NULL;
perf_overflow_handler_t callback = NULL;
/* linux-2.6 commit 38a81da2205f94 */
(void) perf_event_create_kernel_counter(attr,
cpu,
tsk, /* as opposed to int pid */
callback);
}
/*
* This function sets up the performance counter registers to record.
*/
struct perf_event *perf_counter_init(struct task_struct *tsk){
int cpu;
struct perf_event *pevent;
if(attr == NULL) {
attr = kmalloc(sizeof(*attr), GFP_KERNEL);
memset(attr,0,sizeof(*attr));
attr->type = PERF_TYPE_HARDWARE;
//attr->type = PERF_TYPE_RAW;
attr->config = PERF_COUNT_HW_INSTRUCTIONS;
attr->size = sizeof(*attr);
attr->sample_period = 0;
attr->disabled = 0;
attr->inherit = 0;
attr->pinned = 1; //TODO Not sure if we want this set or not yet
//attr->exclusive = 1;
attr->freq = 0;
attr->exclude_user = 0;
attr->exclude_kernel = 1;
attr->exclude_hv = 1;
attr->exclude_idle = 1;
attr->inherit_stat = 1;
//attr->precise_ip = 3;
//attr->wakeup_events = 10000; // wakeup every n events
}
cpu = -1; // count events for this thread on all cpus
pevent = perf_event_create_kernel_counter(attr, cpu, tsk,
(perf_overflow_handler_t) capo_overflow_handler);
if (IS_ERR(pevent)){
BUG();
printk(KERN_CRIT "***** PERFCT: Failed to create kernel counter");
//return PTR_ERR(pevent);
return NULL;
}
if (pevent->state != PERF_EVENT_STATE_ACTIVE) {
printk(KERN_CRIT "***** PERFCT: Failed to enable kernel counter");
kfree(attr);
attr=NULL;
perf_event_release_kernel(pevent);
BUG();
//return -EBUSY;
return NULL;
}
return pevent;
}
static int nmi_timer_start_cpu(int cpu)
{
struct perf_event *event = per_cpu(nmi_timer_events, cpu);
if (!event) {
event = perf_event_create_kernel_counter(&nmi_timer_attr, cpu, NULL,
nmi_timer_callback, NULL);
if (IS_ERR(event))
return PTR_ERR(event);
per_cpu(nmi_timer_events, cpu) = event;
}
if (event && ctr_running)
perf_event_enable(event);
return 0;
}
static int hrprof_init_event(int cpu) {
hrprof_cpu_t* event = per_cpu_ptr(&hrprof_cpu_event, cpu);
spin_lock_init(&event->lock);
event->head = 0;
event->tail = 0;
event->event = perf_event_create_kernel_counter(
&pe_attr, cpu, NULL, overflow_handler, NULL);
if(IS_ERR(event->event)) {
return PTR_ERR(event->event);
}
hrtimer_init(&event->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
event->hrtimer.function = hrprof_timer_notify;
return 0;
}
/**
* register_wide_hw_breakpoint - register a wide breakpoint in the kernel
* @attr: breakpoint attributes
* @triggered: callback to trigger when we hit the breakpoint
*
* @return a set of per_cpu pointers to perf events
*/
struct perf_event * __percpu *
register_wide_hw_breakpoint(struct perf_event_attr *attr,
perf_overflow_handler_t triggered)
{
struct perf_event * __percpu *cpu_events, **pevent, *bp;
long err;
int cpu;
cpu_events = alloc_percpu(typeof(*cpu_events));
if (!cpu_events)
return (void __percpu __force *)ERR_PTR(-ENOMEM);
get_online_cpus();
for_each_online_cpu(cpu) {
pevent = per_cpu_ptr(cpu_events, cpu);
bp = perf_event_create_kernel_counter(attr, cpu, -1, triggered);
*pevent = bp;
if (IS_ERR(bp)) {
err = PTR_ERR(bp);
goto fail;
}
}
put_online_cpus();
return cpu_events;
fail:
for_each_online_cpu(cpu) {
pevent = per_cpu_ptr(cpu_events, cpu);
if (IS_ERR(*pevent))
break;
unregister_hw_breakpoint(*pevent);
}
put_online_cpus();
free_percpu(cpu_events);
return (void __percpu __force *)ERR_PTR(err);
}
int watchdog_nmi_enable(unsigned int cpu)
{
struct perf_event_attr *wd_attr;
struct perf_event *event = per_cpu(watchdog_ev, cpu);
/* nothing to do if the hard lockup detector is disabled */
if (!(watchdog_enabled & NMI_WATCHDOG_ENABLED))
goto out;
/* is it already setup and enabled? */
if (event && event->state > PERF_EVENT_STATE_OFF)
goto out;
/* it is setup but not enabled */
if (event != NULL)
goto out_enable;
wd_attr = &wd_hw_attr;
wd_attr->sample_period = hw_nmi_get_sample_period(watchdog_thresh);
/* Try to register using hardware perf events */
event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback, NULL);
/* save cpu0 error for future comparision */
if (cpu == 0 && IS_ERR(event))
cpu0_err = PTR_ERR(event);
if (!IS_ERR(event)) {
/* only print for cpu0 or different than cpu0 */
if (cpu == 0 || cpu0_err)
pr_info("enabled on all CPUs, permanently consumes one hw-PMU counter.\n");
goto out_save;
}
/*
* Disable the hard lockup detector if _any_ CPU fails to set up
* set up the hardware perf event. The watchdog() function checks
* the NMI_WATCHDOG_ENABLED bit periodically.
*
* The barriers are for syncing up watchdog_enabled across all the
* cpus, as clear_bit() does not use barriers.
*/
smp_mb__before_atomic();
clear_bit(NMI_WATCHDOG_ENABLED_BIT, &watchdog_enabled);
smp_mb__after_atomic();
/* skip displaying the same error again */
if (cpu > 0 && (PTR_ERR(event) == cpu0_err))
return PTR_ERR(event);
/* vary the KERN level based on the returned errno */
if (PTR_ERR(event) == -EOPNOTSUPP)
pr_info("disabled (cpu%i): not supported (no LAPIC?)\n", cpu);
else if (PTR_ERR(event) == -ENOENT)
pr_warn("disabled (cpu%i): hardware events not enabled\n",
cpu);
else
pr_err("disabled (cpu%i): unable to create perf event: %ld\n",
cpu, PTR_ERR(event));
pr_info("Shutting down hard lockup detector on all cpus\n");
return PTR_ERR(event);
/* success path */
out_save:
per_cpu(watchdog_ev, cpu) = event;
out_enable:
perf_event_enable(per_cpu(watchdog_ev, cpu));
out:
return 0;
}
