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/**
* Copyright (C) ARM Limited 2012. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#if defined(__arm__) && (GATOR_PERF_PMU_SUPPORT)
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <asm/pmu.h>
extern int pmnc_counters;
extern int ccnt;
extern unsigned long pmnc_enabled[];
extern unsigned long pmnc_event[];
extern unsigned long pmnc_count[];
extern unsigned long pmnc_key[];
static DEFINE_PER_CPU(struct perf_event *, pevent);
static DEFINE_PER_CPU(struct perf_event_attr *, pevent_attr);
static DEFINE_PER_CPU(int, key);
static DEFINE_PER_CPU(unsigned int, prev_value);
#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 1, 0)
static void ebs_overflow_handler(struct perf_event *event, int unused, struct perf_sample_data *data, struct pt_regs *regs)
#else
static void ebs_overflow_handler(struct perf_event *event, struct perf_sample_data *data, struct pt_regs *regs)
#endif
{
unsigned int value, delta, cpu = smp_processor_id(), buftype = EVENT_BUF;
if (event != per_cpu(pevent, cpu))
return;
if (buffer_check_space(cpu, buftype, 5 * MAXSIZE_PACK32 + MAXSIZE_PACK64)) {
value = local64_read(&event->count);
delta = value - per_cpu(prev_value, cpu);
per_cpu(prev_value, cpu) = value;
// Counters header
gator_buffer_write_packed_int(cpu, buftype, MESSAGE_COUNTERS); // type
gator_buffer_write_packed_int64(cpu, buftype, gator_get_time()); // time
// Output counter
gator_buffer_write_packed_int(cpu, buftype, 2); // length
gator_buffer_write_packed_int(cpu, buftype, per_cpu(key, cpu)); // key
gator_buffer_write_packed_int(cpu, buftype, delta); // delta
// End Counters, length of zero
gator_buffer_write_packed_int(cpu, buftype, 0);
}
// Output backtrace
if (buffer_check_space(cpu, buftype, gator_backtrace_depth * 2 * MAXSIZE_PACK32))
gator_add_sample(cpu, buftype, regs);
// Check and commit; commit is set to occur once buffer is 3/4 full
buffer_check(cpu, buftype);
}
static void gator_event_sampling_online(void)
{
int cpu = smp_processor_id(), buftype = EVENT_BUF;
// read the counter and toss the invalid data, return zero instead
struct perf_event * ev = per_cpu(pevent, cpu);
if (ev != NULL && ev->state == PERF_EVENT_STATE_ACTIVE) {
ev->pmu->read(ev);
per_cpu(prev_value, cpu) = local64_read(&ev->count);
// Counters header
gator_buffer_write_packed_int(cpu, buftype, MESSAGE_COUNTERS); // type
gator_buffer_write_packed_int64(cpu, buftype, gator_get_time()); // time
// Output counter
gator_buffer_write_packed_int(cpu, buftype, 2); // length
gator_buffer_write_packed_int(cpu, buftype, per_cpu(key, cpu)); // key
gator_buffer_write_packed_int(cpu, buftype, 0); // delta - zero for initialization
// End Counters, length of zero
gator_buffer_write_packed_int(cpu, buftype, 0);
}
}
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);
}
static void gator_event_sampling_offline_dispatch(int cpu)
{
if (per_cpu(pevent, cpu)) {
perf_event_release_kernel(per_cpu(pevent, cpu));
per_cpu(pevent, cpu) = NULL;
}
}
static int gator_event_sampling_start(void)
{
int cnt, event = 0, count = 0, ebs_key = 0, cpu;
for_each_present_cpu(cpu) {
per_cpu(pevent, cpu) = NULL;
per_cpu(pevent_attr, cpu) = NULL;
}
event_based_sampling = false;
for (cnt = 0; cnt < pmnc_counters; cnt++) {
if (pmnc_count[cnt] > 0) {
event_based_sampling = true;
event = pmnc_event[cnt];
count = pmnc_count[cnt];
ebs_key = pmnc_key[cnt];
break;
}
}
if (!event_based_sampling)
return 0;
for_each_present_cpu(cpu) {
u32 size = sizeof(struct perf_event_attr);
per_cpu(pevent_attr, cpu) = kmalloc(size, GFP_KERNEL);
if (!per_cpu(pevent_attr, cpu))
return -1;
memset(per_cpu(pevent_attr, cpu), 0, size);
per_cpu(pevent_attr, cpu)->type = PERF_TYPE_RAW;
per_cpu(pevent_attr, cpu)->size = size;
per_cpu(pevent_attr, cpu)->config = event;
per_cpu(pevent_attr, cpu)->sample_period = count;
per_cpu(pevent_attr, cpu)->pinned = 1;
// handle special case for ccnt
if (cnt == ccnt) {
per_cpu(pevent_attr, cpu)->type = PERF_TYPE_HARDWARE;
per_cpu(pevent_attr, cpu)->config = PERF_COUNT_HW_CPU_CYCLES;
}
per_cpu(key, cpu) = ebs_key;
}
return 0;
}
static void gator_event_sampling_stop(void)
{
int cpu;
for_each_present_cpu(cpu) {
if (per_cpu(pevent_attr, cpu)) {
kfree(per_cpu(pevent_attr, cpu));
per_cpu(pevent_attr, cpu) = NULL;
}
}
}
#else
static void gator_event_sampling_online(void) {}
static void gator_event_sampling_online_dispatch(int cpu) {}
static void gator_event_sampling_offline_dispatch(int cpu) {}
static int gator_event_sampling_start(void) {return 0;}
static void gator_event_sampling_stop(void) {}
#endif
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