[lttng-modules.git] / lttng-context-tid.c

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

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <lttng/events.h>
#include <ringbuffer/frontend_types.h>
#include <wrapper/vmalloc.h>
#include <lttng/tracer.h>

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

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

static
void tid_record(struct lttng_ctx_field *field,
		 struct lib_ring_buffer_ctx *ctx,
		 struct lttng_channel *chan)
{
	pid_t tid;

	tid = task_pid_nr(current);
	lib_ring_buffer_align_ctx(ctx, lttng_alignof(tid));
	chan->ops->event_write(ctx, &tid, sizeof(tid));
}

static
void tid_get_value(struct lttng_ctx_field *field,
		struct lttng_probe_ctx *lttng_probe_ctx,
		union lttng_ctx_value *value)
{
	pid_t tid;

	tid = task_pid_nr(current);
	value->s64 = tid;
}

int lttng_add_tid_to_ctx(struct lttng_ctx **ctx)
{
	struct lttng_ctx_field *field;

	field = lttng_append_context(ctx);
	if (!field)
		return -ENOMEM;
	if (lttng_find_context(*ctx, "tid")) {
		lttng_remove_context_field(ctx, field);
		return -EEXIST;
	}
	field->event_field.name = "tid";
	field->event_field.type.atype = atype_integer;
	field->event_field.type.u.integer.size = sizeof(pid_t) * CHAR_BIT;
	field->event_field.type.u.integer.alignment = lttng_alignof(pid_t) * CHAR_BIT;
	field->event_field.type.u.integer.signedness = lttng_is_signed_type(pid_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 = tid_get_size;
	field->record = tid_record;
	field->get_value = tid_get_value;
	lttng_context_update(*ctx);
	wrapper_vmalloc_sync_mappings();
	return 0;
}
EXPORT_SYMBOL_GPL(lttng_add_tid_to_ctx);
Commit	Line	Data
b7cdc182	1	/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
9f36eaed	2	*
886d51a3	3	* lttng-context-tid.c
b64bc438 MD	4	*
	5	* LTTng TID context.
	6	*
886d51a3	7	* Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
b64bc438 MD	8	*/
	9
	10	#include <linux/module.h>
	11	#include <linux/slab.h>
	12	#include <linux/sched.h>
2df37e95	13	#include <lttng/events.h>
24591303	14	#include <ringbuffer/frontend_types.h>
241ae9a8	15	#include <wrapper/vmalloc.h>
2df37e95	16	#include <lttng/tracer.h>
b64bc438 MD	17
	18	static
	19	size_t tid_get_size(size_t offset)
	20	{
	21	size_t size = 0;
	22
a90917c3	23	size += lib_ring_buffer_align(offset, lttng_alignof(pid_t));
b64bc438 MD	24	size += sizeof(pid_t);
	25	return size;
	26	}
	27
	28	static
	29	void tid_record(struct lttng_ctx_field *field,
	30	struct lib_ring_buffer_ctx *ctx,
a90917c3	31	struct lttng_channel *chan)
b64bc438 MD	32	{
	33	pid_t tid;
	34
	35	tid = task_pid_nr(current);
a90917c3	36	lib_ring_buffer_align_ctx(ctx, lttng_alignof(tid));
b64bc438 MD	37	chan->ops->event_write(ctx, &tid, sizeof(tid));
	38	}
	39
f127e61e MD	40	static
f127e61e MD	41	void tid_get_value(struct lttng_ctx_field *field,
79150a49	42	struct lttng_probe_ctx *lttng_probe_ctx,
f127e61e MD	43	union lttng_ctx_value *value)
	44	{
	45	pid_t tid;
	46
	47	tid = task_pid_nr(current);
	48	value->s64 = tid;
	49	}
	50
b64bc438 MD	51	int lttng_add_tid_to_ctx(struct lttng_ctx **ctx)
	52	{
	53	struct lttng_ctx_field *field;
b64bc438 MD	54
	55	field = lttng_append_context(ctx);
	56	if (!field)
09fec6b4	57	return -ENOMEM;
44252f0f MD	58	if (lttng_find_context(*ctx, "tid")) {
	59	lttng_remove_context_field(ctx, field);
	60	return -EEXIST;
	61	}
b64bc438 MD	62	field->event_field.name = "tid";
b64bc438 MD	63	field->event_field.type.atype = atype_integer;
ceabb767 MD	64	field->event_field.type.u.integer.size = sizeof(pid_t) * CHAR_BIT;
	65	field->event_field.type.u.integer.alignment = lttng_alignof(pid_t) * CHAR_BIT;
	66	field->event_field.type.u.integer.signedness = lttng_is_signed_type(pid_t);
	67	field->event_field.type.u.integer.reverse_byte_order = 0;
	68	field->event_field.type.u.integer.base = 10;
	69	field->event_field.type.u.integer.encoding = lttng_encode_none;
b64bc438 MD	70	field->get_size = tid_get_size;
b64bc438 MD	71	field->record = tid_record;
f127e61e	72	field->get_value = tid_get_value;
a9dd15da	73	lttng_context_update(*ctx);
263b6c88	74	wrapper_vmalloc_sync_mappings();
b64bc438 MD	75	return 0;
	76	}
	77	EXPORT_SYMBOL_GPL(lttng_add_tid_to_ctx);