[lttng-modules.git] / lttng-context-perf-counters.c

/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
 *
 * lttng-context-perf-counters.c
 *
 * LTTng performance monitoring counters (perf-counters) integration module.
 *
 * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/perf_event.h>
#include <linux/list.h>
#include <linux/string.h>
#include <linux/cpu.h>
#include <linux/mm.h>
#include <lttng-events.h>
#include <wrapper/ringbuffer/frontend_types.h>
#include <lttng-tracer.h>

static
size_t perf_counter_get_size(size_t offset)
{
	size_t size = 0;

	size += lib_ring_buffer_align(offset, lttng_alignof(uint64_t));
	size += sizeof(uint64_t);
	return size;
}

static
void perf_counter_record(struct lttng_ctx_field *field,
			 struct lib_ring_buffer_ctx *ctx,
			 struct lttng_channel *chan)
{
	struct perf_event *event;
	uint64_t value;

	event = field->u.perf_counter->e[ctx->cpu];
	if (likely(event)) {
		if (unlikely(event->state == PERF_EVENT_STATE_ERROR)) {
			value = 0;
		} else {
			event->pmu->read(event);
			value = local64_read(&event->count);
		}
	} else {
		/*
		 * Perf chooses not to be clever and not to support enabling a
		 * perf counter before the cpu is brought up. Therefore, we need
		 * to support having events coming (e.g. scheduler events)
		 * before the counter is setup. Write an arbitrary 0 in this
		 * case.
		 */
		value = 0;
	}
	lib_ring_buffer_align_ctx(ctx, lttng_alignof(value));
	chan->ops->event_write(ctx, &value, sizeof(value));
}

static
void overflow_callback(struct perf_event *event,
		       struct perf_sample_data *data,
		       struct pt_regs *regs)
{
}

static
void lttng_destroy_perf_counter_field(struct lttng_ctx_field *field)
{
	struct perf_event **events = field->u.perf_counter->e;

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
	{
		int ret;

		ret = cpuhp_state_remove_instance(lttng_hp_online,
			&field->u.perf_counter->cpuhp_online.node);
		WARN_ON(ret);
		ret = cpuhp_state_remove_instance(lttng_hp_prepare,
			&field->u.perf_counter->cpuhp_prepare.node);
		WARN_ON(ret);
	}
#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
	{
		int cpu;

		get_online_cpus();
		for_each_online_cpu(cpu)
			perf_event_release_kernel(events[cpu]);
		put_online_cpus();
#ifdef CONFIG_HOTPLUG_CPU
		unregister_cpu_notifier(&field->u.perf_counter->nb);
#endif
	}
#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
	kfree(field->event_field.name);
	kfree(field->u.perf_counter->attr);
	kvfree(events);
	kfree(field->u.perf_counter);
}

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))

int lttng_cpuhp_perf_counter_online(unsigned int cpu,
		struct lttng_cpuhp_node *node)
{
	struct lttng_perf_counter_field *perf_field =
		container_of(node, struct lttng_perf_counter_field,
				cpuhp_online);
	struct perf_event **events = perf_field->e;
	struct perf_event_attr *attr = perf_field->attr;
	struct perf_event *pevent;

	pevent = perf_event_create_kernel_counter(attr,
			cpu, NULL, overflow_callback, NULL);
	if (!pevent || IS_ERR(pevent))
		return -EINVAL;
	if (pevent->state == PERF_EVENT_STATE_ERROR) {
		perf_event_release_kernel(pevent);
		return -EINVAL;
	}
	barrier();	/* Create perf counter before setting event */
	events[cpu] = pevent;
	return 0;
}

int lttng_cpuhp_perf_counter_dead(unsigned int cpu,
		struct lttng_cpuhp_node *node)
{
	struct lttng_perf_counter_field *perf_field =
		container_of(node, struct lttng_perf_counter_field,
				cpuhp_prepare);
	struct perf_event **events = perf_field->e;
	struct perf_event *pevent;

	pevent = events[cpu];
	events[cpu] = NULL;
	barrier();	/* NULLify event before perf counter teardown */
	perf_event_release_kernel(pevent);
	return 0;
}

#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */

#ifdef CONFIG_HOTPLUG_CPU

/**
 *	lttng_perf_counter_hp_callback - CPU hotplug callback
 *	@nb: notifier block
 *	@action: hotplug action to take
 *	@hcpu: CPU number
 *
 *	Returns the success/failure of the operation. (%NOTIFY_OK, %NOTIFY_BAD)
 *
 * We can setup perf counters when the cpu is online (up prepare seems to be too
 * soon).
 */
static
int lttng_perf_counter_cpu_hp_callback(struct notifier_block *nb,
						 unsigned long action,
						 void *hcpu)
{
	unsigned int cpu = (unsigned long) hcpu;
	struct lttng_perf_counter_field *perf_field =
		container_of(nb, struct lttng_perf_counter_field, nb);
	struct perf_event **events = perf_field->e;
	struct perf_event_attr *attr = perf_field->attr;
	struct perf_event *pevent;

	if (!perf_field->hp_enable)
		return NOTIFY_OK;

	switch (action) {
	case CPU_ONLINE:
	case CPU_ONLINE_FROZEN:
		pevent = perf_event_create_kernel_counter(attr,
				cpu, NULL, overflow_callback, NULL);
		if (!pevent || IS_ERR(pevent))
			return NOTIFY_BAD;
		if (pevent->state == PERF_EVENT_STATE_ERROR) {
			perf_event_release_kernel(pevent);
			return NOTIFY_BAD;
		}
		barrier();	/* Create perf counter before setting event */
		events[cpu] = pevent;
		break;
	case CPU_UP_CANCELED:
	case CPU_UP_CANCELED_FROZEN:
	case CPU_DEAD:
	case CPU_DEAD_FROZEN:
		pevent = events[cpu];
		events[cpu] = NULL;
		barrier();	/* NULLify event before perf counter teardown */
		perf_event_release_kernel(pevent);
		break;
	}
	return NOTIFY_OK;
}

#endif

#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */

int lttng_add_perf_counter_to_ctx(uint32_t type,
				  uint64_t config,
				  const char *name,
				  struct lttng_ctx **ctx)
{
	struct lttng_ctx_field *field;
	struct lttng_perf_counter_field *perf_field;
	struct perf_event **events;
	struct perf_event_attr *attr;
	int ret;
	char *name_alloc;

	events = kvzalloc(num_possible_cpus() * sizeof(*events), GFP_KERNEL);
	if (!events)
		return -ENOMEM;

	attr = kzalloc(sizeof(struct perf_event_attr), GFP_KERNEL);
	if (!attr) {
		ret = -ENOMEM;
		goto error_attr;
	}

	attr->type = type;
	attr->config = config;
	attr->size = sizeof(struct perf_event_attr);
	attr->pinned = 1;
	attr->disabled = 0;

	perf_field = kzalloc(sizeof(struct lttng_perf_counter_field), GFP_KERNEL);
	if (!perf_field) {
		ret = -ENOMEM;
		goto error_alloc_perf_field;
	}
	perf_field->e = events;
	perf_field->attr = attr;

	name_alloc = kstrdup(name, GFP_KERNEL);
	if (!name_alloc) {
		ret = -ENOMEM;
		goto name_alloc_error;
	}

	field = lttng_append_context(ctx);
	if (!field) {
		ret = -ENOMEM;
		goto append_context_error;
	}
	if (lttng_find_context(*ctx, name_alloc)) {
		ret = -EEXIST;
		goto find_error;
	}

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))

	perf_field->cpuhp_prepare.component = LTTNG_CONTEXT_PERF_COUNTERS;
	ret = cpuhp_state_add_instance(lttng_hp_prepare,
		&perf_field->cpuhp_prepare.node);
	if (ret)
		goto cpuhp_prepare_error;

	perf_field->cpuhp_online.component = LTTNG_CONTEXT_PERF_COUNTERS;
	ret = cpuhp_state_add_instance(lttng_hp_online,
		&perf_field->cpuhp_online.node);
	if (ret)
		goto cpuhp_online_error;

#else	/* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
	{
		int cpu;

#ifdef CONFIG_HOTPLUG_CPU
		perf_field->nb.notifier_call =
			lttng_perf_counter_cpu_hp_callback;
		perf_field->nb.priority = 0;
		register_cpu_notifier(&perf_field->nb);
#endif
		get_online_cpus();
		for_each_online_cpu(cpu) {
			events[cpu] = perf_event_create_kernel_counter(attr,
						cpu, NULL, overflow_callback, NULL);
			if (!events[cpu] || IS_ERR(events[cpu])) {
				ret = -EINVAL;
				goto counter_error;
			}
			if (events[cpu]->state == PERF_EVENT_STATE_ERROR) {
				ret = -EBUSY;
				goto counter_busy;
			}
		}
		put_online_cpus();
		perf_field->hp_enable = 1;
	}
#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */

	field->destroy = lttng_destroy_perf_counter_field;

	field->event_field.name = name_alloc;
	field->event_field.type.atype = atype_integer;
	field->event_field.type.u.integer.size = sizeof(uint64_t) * CHAR_BIT;
	field->event_field.type.u.integer.alignment = lttng_alignof(uint64_t) * CHAR_BIT;
	field->event_field.type.u.integer.signedness = lttng_is_signed_type(uint64_t);
	field->event_field.type.u.integer.reverse_byte_order = 0;
	field->event_field.type.u.integer.base = 10;
	field->event_field.type.u.integer.encoding = lttng_encode_none;
	field->get_size = perf_counter_get_size;
	field->record = perf_counter_record;
	field->u.perf_counter = perf_field;
	lttng_context_update(*ctx);

	return 0;

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
cpuhp_online_error:
	{
		int remove_ret;

		remove_ret = cpuhp_state_remove_instance(lttng_hp_prepare,
				&perf_field->cpuhp_prepare.node);
		WARN_ON(remove_ret);
	}
cpuhp_prepare_error:
#else	/* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
counter_busy:
counter_error:
	{
		int cpu;

		for_each_online_cpu(cpu) {
			if (events[cpu] && !IS_ERR(events[cpu]))
				perf_event_release_kernel(events[cpu]);
		}
		put_online_cpus();
#ifdef CONFIG_HOTPLUG_CPU
		unregister_cpu_notifier(&perf_field->nb);
#endif
	}
#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
find_error:
	lttng_remove_context_field(ctx, field);
append_context_error:
	kfree(name_alloc);
name_alloc_error:
	kfree(perf_field);
error_alloc_perf_field:
	kfree(attr);
error_attr:
	kvfree(events);
	return ret;
}
Commit	Line	Data
b7cdc182	1	/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
9f36eaed	2	*
886d51a3	3	* lttng-context-perf-counters.c
833ad6a0 MD	4	*
	5	* LTTng performance monitoring counters (perf-counters) integration module.
	6	*
886d51a3	7	* Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
833ad6a0 MD	8	*/
	9
	10	#include <linux/module.h>
	11	#include <linux/slab.h>
	12	#include <linux/perf_event.h>
	13	#include <linux/list.h>
c24a0d71	14	#include <linux/string.h>
5ca7b8a3	15	#include <linux/cpu.h>
c50bdba2	16	#include <linux/mm.h>
241ae9a8 MD	17	#include <lttng-events.h>
241ae9a8 MD	18	#include <wrapper/ringbuffer/frontend_types.h>
241ae9a8	19	#include <lttng-tracer.h>
833ad6a0	20
f1676205 MD	21	static
	22	size_t perf_counter_get_size(size_t offset)
	23	{
	24	size_t size = 0;
	25
a90917c3	26	size += lib_ring_buffer_align(offset, lttng_alignof(uint64_t));
f1676205 MD	27	size += sizeof(uint64_t);
	28	return size;
	29	}
	30
833ad6a0 MD	31	static
	32	void perf_counter_record(struct lttng_ctx_field *field,
	33	struct lib_ring_buffer_ctx *ctx,
a90917c3	34	struct lttng_channel *chan)
833ad6a0 MD	35	{
	36	struct perf_event *event;
	37	uint64_t value;
	38
2001023e	39	event = field->u.perf_counter->e[ctx->cpu];
0478c519	40	if (likely(event)) {
7b745a96 MD	41	if (unlikely(event->state == PERF_EVENT_STATE_ERROR)) {
	42	value = 0;
	43	} else {
	44	event->pmu->read(event);
	45	value = local64_read(&event->count);
	46	}
f91fd73b MD	47	} else {
	48	/*
	49	* Perf chooses not to be clever and not to support enabling a
	50	* perf counter before the cpu is brought up. Therefore, we need
	51	* to support having events coming (e.g. scheduler events)
	52	* before the counter is setup. Write an arbitrary 0 in this
	53	* case.
	54	*/
	55	value = 0;
	56	}
a90917c3	57	lib_ring_buffer_align_ctx(ctx, lttng_alignof(value));
833ad6a0 MD	58	chan->ops->event_write(ctx, &value, sizeof(value));
	59	}
	60
90f5546c MD	61	static
	62	void overflow_callback(struct perf_event *event,
	63	struct perf_sample_data *data,
	64	struct pt_regs *regs)
	65	{
	66	}
833ad6a0	67
2dccf128 MD	68	static
	69	void lttng_destroy_perf_counter_field(struct lttng_ctx_field *field)
	70	{
2001023e	71	struct perf_event **events = field->u.perf_counter->e;
2dccf128	72
1e367326 MD	73	#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
	74	{
	75	int ret;
	76
	77	ret = cpuhp_state_remove_instance(lttng_hp_online,
	78	&field->u.perf_counter->cpuhp_online.node);
	79	WARN_ON(ret);
	80	ret = cpuhp_state_remove_instance(lttng_hp_prepare,
	81	&field->u.perf_counter->cpuhp_prepare.node);
	82	WARN_ON(ret);
	83	}
	84	#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
	85	{
	86	int cpu;
	87
	88	get_online_cpus();
	89	for_each_online_cpu(cpu)
	90	perf_event_release_kernel(events[cpu]);
	91	put_online_cpus();
8289661d	92	#ifdef CONFIG_HOTPLUG_CPU
1e367326	93	unregister_cpu_notifier(&field->u.perf_counter->nb);
8289661d	94	#endif
1e367326 MD	95	}
1e367326 MD	96	#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
c24a0d71	97	kfree(field->event_field.name);
2001023e	98	kfree(field->u.perf_counter->attr);
c50bdba2	99	kvfree(events);
2001023e	100	kfree(field->u.perf_counter);
2dccf128 MD	101	}
2dccf128 MD	102
1e367326 MD	103	#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
	104
	105	int lttng_cpuhp_perf_counter_online(unsigned int cpu,
	106	struct lttng_cpuhp_node *node)
	107	{
	108	struct lttng_perf_counter_field *perf_field =
	109	container_of(node, struct lttng_perf_counter_field,
	110	cpuhp_online);
	111	struct perf_event **events = perf_field->e;
	112	struct perf_event_attr *attr = perf_field->attr;
	113	struct perf_event *pevent;
	114
1cacbdc9 MD	115	pevent = perf_event_create_kernel_counter(attr,
1cacbdc9 MD	116	cpu, NULL, overflow_callback, NULL);
1e367326 MD	117	if (!pevent \|\| IS_ERR(pevent))
	118	return -EINVAL;
	119	if (pevent->state == PERF_EVENT_STATE_ERROR) {
	120	perf_event_release_kernel(pevent);
	121	return -EINVAL;
	122	}
	123	barrier(); /* Create perf counter before setting event */
	124	events[cpu] = pevent;
	125	return 0;
	126	}
	127
	128	int lttng_cpuhp_perf_counter_dead(unsigned int cpu,
	129	struct lttng_cpuhp_node *node)
	130	{
	131	struct lttng_perf_counter_field *perf_field =
	132	container_of(node, struct lttng_perf_counter_field,
	133	cpuhp_prepare);
	134	struct perf_event **events = perf_field->e;
	135	struct perf_event *pevent;
	136
	137	pevent = events[cpu];
	138	events[cpu] = NULL;
	139	barrier(); /* NULLify event before perf counter teardown */
	140	perf_event_release_kernel(pevent);
	141	return 0;
	142	}
	143
	144	#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
	145
8289661d MD	146	#ifdef CONFIG_HOTPLUG_CPU
	147
	148	/**
	149	* lttng_perf_counter_hp_callback - CPU hotplug callback
	150	* @nb: notifier block
	151	* @action: hotplug action to take
	152	* @hcpu: CPU number
	153	*
	154	* Returns the success/failure of the operation. (%NOTIFY_OK, %NOTIFY_BAD)
	155	*
	156	* We can setup perf counters when the cpu is online (up prepare seems to be too
	157	* soon).
	158	*/
	159	static
e8f071d5	160	int lttng_perf_counter_cpu_hp_callback(struct notifier_block *nb,
8289661d MD	161	unsigned long action,
	162	void *hcpu)
	163	{
	164	unsigned int cpu = (unsigned long) hcpu;
2001023e MD	165	struct lttng_perf_counter_field *perf_field =
	166	container_of(nb, struct lttng_perf_counter_field, nb);
	167	struct perf_event **events = perf_field->e;
	168	struct perf_event_attr *attr = perf_field->attr;
f91fd73b	169	struct perf_event *pevent;
8289661d	170
2001023e	171	if (!perf_field->hp_enable)
8289661d MD	172	return NOTIFY_OK;
	173
	174	switch (action) {
	175	case CPU_ONLINE:
	176	case CPU_ONLINE_FROZEN:
1cacbdc9 MD	177	pevent = perf_event_create_kernel_counter(attr,
1cacbdc9 MD	178	cpu, NULL, overflow_callback, NULL);
0478c519	179	if (!pevent \|\| IS_ERR(pevent))
8289661d	180	return NOTIFY_BAD;
7b745a96 MD	181	if (pevent->state == PERF_EVENT_STATE_ERROR) {
	182	perf_event_release_kernel(pevent);
	183	return NOTIFY_BAD;
	184	}
f91fd73b MD	185	barrier(); /* Create perf counter before setting event */
f91fd73b MD	186	events[cpu] = pevent;
8289661d MD	187	break;
	188	case CPU_UP_CANCELED:
	189	case CPU_UP_CANCELED_FROZEN:
	190	case CPU_DEAD:
	191	case CPU_DEAD_FROZEN:
f91fd73b MD	192	pevent = events[cpu];
	193	events[cpu] = NULL;
	194	barrier(); /* NULLify event before perf counter teardown */
	195	perf_event_release_kernel(pevent);
8289661d MD	196	break;
	197	}
	198	return NOTIFY_OK;
	199	}
	200
	201	#endif
	202
1e367326 MD	203	#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
1e367326 MD	204
833ad6a0 MD	205	int lttng_add_perf_counter_to_ctx(uint32_t type,
833ad6a0 MD	206	uint64_t config,
c24a0d71	207	const char *name,
2dccf128	208	struct lttng_ctx **ctx)
833ad6a0 MD	209	{
833ad6a0 MD	210	struct lttng_ctx_field *field;
2001023e	211	struct lttng_perf_counter_field *perf_field;
833ad6a0 MD	212	struct perf_event **events;
	213	struct perf_event_attr *attr;
	214	int ret;
c24a0d71	215	char *name_alloc;
833ad6a0	216
c50bdba2	217	events = kvzalloc(num_possible_cpus() * sizeof(*events), GFP_KERNEL);
833ad6a0 MD	218	if (!events)
	219	return -ENOMEM;
	220
2001023e	221	attr = kzalloc(sizeof(struct perf_event_attr), GFP_KERNEL);
833ad6a0 MD	222	if (!attr) {
	223	ret = -ENOMEM;
	224	goto error_attr;
	225	}
	226
	227	attr->type = type;
	228	attr->config = config;
	229	attr->size = sizeof(struct perf_event_attr);
	230	attr->pinned = 1;
	231	attr->disabled = 0;
	232
2001023e MD	233	perf_field = kzalloc(sizeof(struct lttng_perf_counter_field), GFP_KERNEL);
	234	if (!perf_field) {
	235	ret = -ENOMEM;
	236	goto error_alloc_perf_field;
	237	}
	238	perf_field->e = events;
	239	perf_field->attr = attr;
	240
c24a0d71	241	name_alloc = kstrdup(name, GFP_KERNEL);
bef96e48 MD	242	if (!name_alloc) {
bef96e48 MD	243	ret = -ENOMEM;
c24a0d71	244	goto name_alloc_error;
bef96e48	245	}
c24a0d71	246
2dccf128 MD	247	field = lttng_append_context(ctx);
	248	if (!field) {
	249	ret = -ENOMEM;
8289661d	250	goto append_context_error;
833ad6a0	251	}
2001023e	252	if (lttng_find_context(*ctx, name_alloc)) {
44252f0f MD	253	ret = -EEXIST;
	254	goto find_error;
	255	}
8289661d	256
1e367326 MD	257	#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
	258
	259	perf_field->cpuhp_prepare.component = LTTNG_CONTEXT_PERF_COUNTERS;
	260	ret = cpuhp_state_add_instance(lttng_hp_prepare,
	261	&perf_field->cpuhp_prepare.node);
	262	if (ret)
	263	goto cpuhp_prepare_error;
	264
	265	perf_field->cpuhp_online.component = LTTNG_CONTEXT_PERF_COUNTERS;
	266	ret = cpuhp_state_add_instance(lttng_hp_online,
	267	&perf_field->cpuhp_online.node);
	268	if (ret)
	269	goto cpuhp_online_error;
	270
	271	#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
	272	{
	273	int cpu;
	274
8289661d	275	#ifdef CONFIG_HOTPLUG_CPU
1e367326 MD	276	perf_field->nb.notifier_call =
	277	lttng_perf_counter_cpu_hp_callback;
	278	perf_field->nb.priority = 0;
	279	register_cpu_notifier(&perf_field->nb);
8289661d	280	#endif
1e367326 MD	281	get_online_cpus();
1e367326 MD	282	for_each_online_cpu(cpu) {
1cacbdc9 MD	283	events[cpu] = perf_event_create_kernel_counter(attr,
1cacbdc9 MD	284	cpu, NULL, overflow_callback, NULL);
1e367326 MD	285	if (!events[cpu] \|\| IS_ERR(events[cpu])) {
	286	ret = -EINVAL;
	287	goto counter_error;
	288	}
	289	if (events[cpu]->state == PERF_EVENT_STATE_ERROR) {
	290	ret = -EBUSY;
	291	goto counter_busy;
	292	}
7b745a96	293	}
1e367326 MD	294	put_online_cpus();
1e367326 MD	295	perf_field->hp_enable = 1;
8289661d	296	}
1e367326	297	#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
8289661d	298
2dccf128	299	field->destroy = lttng_destroy_perf_counter_field;
833ad6a0	300
c24a0d71	301	field->event_field.name = name_alloc;
8070f5c0	302	field->event_field.type.atype = atype_integer;
ceabb767 MD	303	field->event_field.type.u.integer.size = sizeof(uint64_t) * CHAR_BIT;
	304	field->event_field.type.u.integer.alignment = lttng_alignof(uint64_t) * CHAR_BIT;
	305	field->event_field.type.u.integer.signedness = lttng_is_signed_type(uint64_t);
	306	field->event_field.type.u.integer.reverse_byte_order = 0;
	307	field->event_field.type.u.integer.base = 10;
	308	field->event_field.type.u.integer.encoding = lttng_encode_none;
f1676205 MD	309	field->get_size = perf_counter_get_size;
f1676205 MD	310	field->record = perf_counter_record;
2001023e	311	field->u.perf_counter = perf_field;
a9dd15da	312	lttng_context_update(*ctx);
833ad6a0	313
833ad6a0 MD	314	return 0;
833ad6a0 MD	315
1e367326 MD	316	#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
	317	cpuhp_online_error:
	318	{
	319	int remove_ret;
	320
	321	remove_ret = cpuhp_state_remove_instance(lttng_hp_prepare,
	322	&perf_field->cpuhp_prepare.node);
	323	WARN_ON(remove_ret);
	324	}
	325	cpuhp_prepare_error:
	326	#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
7b745a96	327	counter_busy:
8289661d	328	counter_error:
ce4a2f0c MD	329	{
	330	int cpu;
	331
	332	for_each_online_cpu(cpu) {
	333	if (events[cpu] && !IS_ERR(events[cpu]))
	334	perf_event_release_kernel(events[cpu]);
	335	}
	336	put_online_cpus();
8289661d	337	#ifdef CONFIG_HOTPLUG_CPU
ce4a2f0c	338	unregister_cpu_notifier(&perf_field->nb);
8289661d	339	#endif
ce4a2f0c	340	}
1e367326	341	#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
44252f0f	342	find_error:
8289661d MD	343	lttng_remove_context_field(ctx, field);
	344	append_context_error:
	345	kfree(name_alloc);
	346	name_alloc_error:
2001023e MD	347	kfree(perf_field);
2001023e MD	348	error_alloc_perf_field:
833ad6a0 MD	349	kfree(attr);
833ad6a0 MD	350	error_attr:
c50bdba2	351	kvfree(events);
833ad6a0 MD	352	return ret;
833ad6a0 MD	353	}