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

/*
 * lttng-context-tid.c
 *
 * LTTng TID context.
 *
 * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; only
 * version 2.1 of the License.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <lttng-events.h>
#include <wrapper/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.basic.integer.size = sizeof(pid_t) * CHAR_BIT;
	field->event_field.type.u.basic.integer.alignment = lttng_alignof(pid_t) * CHAR_BIT;
	field->event_field.type.u.basic.integer.signedness = lttng_is_signed_type(pid_t);
	field->event_field.type.u.basic.integer.reverse_byte_order = 0;
	field->event_field.type.u.basic.integer.base = 10;
	field->event_field.type.u.basic.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_all();
	return 0;
}
EXPORT_SYMBOL_GPL(lttng_add_tid_to_ctx);
Commit	Line	Data
	1	/*
	2	* lttng-context-tid.c
	3	*
	4	* LTTng TID context.
	5	*
	6	* Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	7	*
	8	* This library is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU Lesser General Public
	10	* License as published by the Free Software Foundation; only
	11	* version 2.1 of the License.
	12	*
	13	* This library is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	* Lesser General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU Lesser General Public
	19	* License along with this library; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	21	*/
	22
	23	#include <linux/module.h>
	24	#include <linux/slab.h>
	25	#include <linux/sched.h>
	26	#include <lttng-events.h>
	27	#include <wrapper/ringbuffer/frontend_types.h>
	28	#include <wrapper/vmalloc.h>
	29	#include <lttng-tracer.h>
	30
	31	static
	32	size_t tid_get_size(size_t offset)
	33	{
	34	size_t size = 0;
	35
	36	size += lib_ring_buffer_align(offset, lttng_alignof(pid_t));
	37	size += sizeof(pid_t);
	38	return size;
	39	}
	40
	41	static
	42	void tid_record(struct lttng_ctx_field *field,
	43	struct lib_ring_buffer_ctx *ctx,
	44	struct lttng_channel *chan)
	45	{
	46	pid_t tid;
	47
	48	tid = task_pid_nr(current);
	49	lib_ring_buffer_align_ctx(ctx, lttng_alignof(tid));
	50	chan->ops->event_write(ctx, &tid, sizeof(tid));
	51	}
	52
	53	static
	54	void tid_get_value(struct lttng_ctx_field *field,
	55	struct lttng_probe_ctx *lttng_probe_ctx,
	56	union lttng_ctx_value *value)
	57	{
	58	pid_t tid;
	59
	60	tid = task_pid_nr(current);
	61	value->s64 = tid;
	62	}
	63
	64	int lttng_add_tid_to_ctx(struct lttng_ctx **ctx)
	65	{
	66	struct lttng_ctx_field *field;
	67
	68	field = lttng_append_context(ctx);
	69	if (!field)
	70	return -ENOMEM;
	71	if (lttng_find_context(*ctx, "tid")) {
	72	lttng_remove_context_field(ctx, field);
	73	return -EEXIST;
	74	}
	75	field->event_field.name = "tid";
	76	field->event_field.type.atype = atype_integer;
	77	field->event_field.type.u.basic.integer.size = sizeof(pid_t) * CHAR_BIT;
	78	field->event_field.type.u.basic.integer.alignment = lttng_alignof(pid_t) * CHAR_BIT;
	79	field->event_field.type.u.basic.integer.signedness = lttng_is_signed_type(pid_t);
	80	field->event_field.type.u.basic.integer.reverse_byte_order = 0;
	81	field->event_field.type.u.basic.integer.base = 10;
	82	field->event_field.type.u.basic.integer.encoding = lttng_encode_none;
	83	field->get_size = tid_get_size;
	84	field->record = tid_record;
	85	field->get_value = tid_get_value;
	86	lttng_context_update(*ctx);
	87	wrapper_vmalloc_sync_all();
	88	return 0;
	89	}
	90	EXPORT_SYMBOL_GPL(lttng_add_tid_to_ctx);