Commit 0e956150 authored by Eugeniy Paltsev's avatar Eugeniy Paltsev Committed by Vineet Gupta
Browse files

ARC: perf: introduce Kernel PMU events support 



Export all available ARC architected hardware events as
kernel PMU events to make non-generic events accessible.

ARC PMU HW allow us to read the list of all available
events names. So we generate kernel PMU event list
dynamically in arc_pmu_device_probe() using
human-readable events names we got from HW instead of
using pre-defined events list.

-------------------------->8--------------------------
$ perf list
  [snip]
  arc_pmu/bdata64/                  [Kernel PMU event]
  arc_pmu/bdcstall/                 [Kernel PMU event]
  arc_pmu/bdslot/                   [Kernel PMU event]
  arc_pmu/bfbmp/                    [Kernel PMU event]
  arc_pmu/bfirqex/                  [Kernel PMU event]
  arc_pmu/bflgstal/                 [Kernel PMU event]
  arc_pmu/bflush/                   [Kernel PMU event]
-------------------------->8--------------------------

Signed-off-by: default avatarEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent 14f81a91

arch/arc/kernel/perf_event.c

+105 −1
Original line number Diff line number Diff line
@@ -17,12 +17,28 @@ 
/* HW holds 8 symbols + one for null terminator */

#define ARCPMU_EVENT_NAME_LEN	9



enum arc_pmu_attr_groups {

	ARCPMU_ATTR_GR_EVENTS,

	ARCPMU_ATTR_GR_FORMATS,

	ARCPMU_NR_ATTR_GR

};



struct arc_pmu_raw_event_entry {

	char name[ARCPMU_EVENT_NAME_LEN];

};



struct arc_pmu {

	struct pmu	pmu;

	unsigned int	irq;

	int		n_counters;

	int		n_events;

	u64		max_period;

	int		ev_hw_idx[PERF_COUNT_ARC_HW_MAX];



	struct arc_pmu_raw_event_entry	*raw_entry;

	struct attribute		**attrs;

	struct perf_pmu_events_attr	*attr;

	const struct attribute_group	*attr_groups[ARCPMU_NR_ATTR_GR + 1];

};



struct arc_pmu_cpu {
@@ -192,6 +208,17 @@ static int arc_pmu_event_init(struct perf_event *event) 
			 (int)hwc->config, arc_pmu_ev_hw_map[ret]);

		return 0;



	case PERF_TYPE_RAW:

		if (event->attr.config >= arc_pmu->n_events)

			return -ENOENT;



		hwc->config |= event->attr.config;

		pr_debug("init raw event with idx %lld \'%s\'\n",

			 event->attr.config,

			 arc_pmu->raw_entry[event->attr.config].name);



		return 0;



	default:

		return -ENOENT;

	}
@@ -442,6 +469,67 @@ static void arc_cpu_pmu_irq_init(void *data) 
	write_aux_reg(ARC_REG_PCT_INT_ACT, 0xffffffff);

}



/* Event field occupies the bottom 15 bits of our config field */

PMU_FORMAT_ATTR(event, "config:0-14");

static struct attribute *arc_pmu_format_attrs[] = {

	&format_attr_event.attr,

	NULL,

};



static struct attribute_group arc_pmu_format_attr_gr = {

	.name = "format",

	.attrs = arc_pmu_format_attrs,

};



static ssize_t arc_pmu_events_sysfs_show(struct device *dev,

					 struct device_attribute *attr,

					 char *page)

{

	struct perf_pmu_events_attr *pmu_attr;



	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);

	return sprintf(page, "event=0x%04llx\n", pmu_attr->id);

}



/*

 * We don't add attrs here as we don't have pre-defined list of perf events.

 * We will generate and add attrs dynamically in probe() after we read HW

 * configuration.

 */

static struct attribute_group arc_pmu_events_attr_gr = {

	.name = "events",

};



static void arc_pmu_add_raw_event_attr(int j, char *str)

{

	memmove(arc_pmu->raw_entry[j].name, str, ARCPMU_EVENT_NAME_LEN - 1);

	arc_pmu->attr[j].attr.attr.name = arc_pmu->raw_entry[j].name;

	arc_pmu->attr[j].attr.attr.mode = VERIFY_OCTAL_PERMISSIONS(0444);

	arc_pmu->attr[j].attr.show = arc_pmu_events_sysfs_show;

	arc_pmu->attr[j].id = j;

	arc_pmu->attrs[j] = &(arc_pmu->attr[j].attr.attr);

}



static int arc_pmu_raw_alloc(struct device *dev)

{

	arc_pmu->attr = devm_kmalloc_array(dev, arc_pmu->n_events + 1,

		sizeof(*arc_pmu->attr), GFP_KERNEL | __GFP_ZERO);

	if (!arc_pmu->attr)

		return -ENOMEM;



	arc_pmu->attrs = devm_kmalloc_array(dev, arc_pmu->n_events + 1,

		sizeof(*arc_pmu->attrs), GFP_KERNEL | __GFP_ZERO);

	if (!arc_pmu->attrs)

		return -ENOMEM;



	arc_pmu->raw_entry = devm_kmalloc_array(dev, arc_pmu->n_events,

		sizeof(*arc_pmu->raw_entry), GFP_KERNEL | __GFP_ZERO);

	if (!arc_pmu->raw_entry)

		return -ENOMEM;



	return 0;

}



static int arc_pmu_device_probe(struct platform_device *pdev)

{

	struct arc_reg_pct_build pct_bcr;
@@ -473,6 +561,11 @@ static int arc_pmu_device_probe(struct platform_device *pdev) 
	if (!arc_pmu)

		return -ENOMEM;



	arc_pmu->n_events = cc_bcr.c;



	if (arc_pmu_raw_alloc(&pdev->dev))

		return -ENOMEM;



	has_interrupts = is_isa_arcv2() ? pct_bcr.i : 0;



	arc_pmu->n_counters = pct_bcr.c;
@@ -504,8 +597,14 @@ static int arc_pmu_device_probe(struct platform_device *pdev) 
				arc_pmu->ev_hw_idx[i] = j;

			}

		}



		arc_pmu_add_raw_event_attr(j, cc_name.str);

	}



	arc_pmu_events_attr_gr.attrs = arc_pmu->attrs;

	arc_pmu->attr_groups[ARCPMU_ATTR_GR_EVENTS] = &arc_pmu_events_attr_gr;

	arc_pmu->attr_groups[ARCPMU_ATTR_GR_FORMATS] = &arc_pmu_format_attr_gr;



	arc_pmu->pmu = (struct pmu) {

		.pmu_enable	= arc_pmu_enable,

		.pmu_disable	= arc_pmu_disable,
@@ -515,6 +614,7 @@ static int arc_pmu_device_probe(struct platform_device *pdev) 
		.start		= arc_pmu_start,

		.stop		= arc_pmu_stop,

		.read		= arc_pmu_read,

		.attr_groups	= arc_pmu->attr_groups,

	};



	if (has_interrupts) {
@@ -536,7 +636,11 @@ static int arc_pmu_device_probe(struct platform_device *pdev) 
	} else

		arc_pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;



	return perf_pmu_register(&arc_pmu->pmu, pdev->name, PERF_TYPE_RAW);

	/*

	 * perf parser doesn't really like '-' symbol in events name, so let's

	 * use '_' in arc pct name as it goes to kernel PMU event prefix.

	 */

	return perf_pmu_register(&arc_pmu->pmu, "arc_pct", PERF_TYPE_RAW);

}



static const struct of_device_id arc_pmu_match[] = {

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