[lttng-ust.git] / liblttng-ust / lttng-context.c

/*
 * lttng-context.c
 *
 * LTTng UST trace/channel/event context management.
 *
 * Copyright (C) 2011 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 <lttng/ust-events.h>
#include <lttng/ust-tracer.h>
#include <lttng/ust-context-provider.h>
#include <urcu-pointer.h>
#include <usterr-signal-safe.h>
#include <helper.h>
#include <string.h>
#include <assert.h>

/*
 * The filter implementation requires that two consecutive "get" for the
 * same context performed by the same thread return the same result.
 */

int lttng_find_context(struct lttng_ctx *ctx, const char *name)
{
	unsigned int i;
	const char *subname;

	if (strncmp(name, "$ctx.", strlen("$ctx.")) == 0) {
		subname = name + strlen("$ctx.");
	} else {
		subname = name;
	}
	for (i = 0; i < ctx->nr_fields; i++) {
		/* Skip allocated (but non-initialized) contexts */
		if (!ctx->fields[i].event_field.name)
			continue;
		if (!strcmp(ctx->fields[i].event_field.name, subname))
			return 1;
	}
	return 0;
}

int lttng_get_context_index(struct lttng_ctx *ctx, const char *name)
{
	unsigned int i;
	const char *subname;

	if (!ctx)
		return -1;
	if (strncmp(name, "$ctx.", strlen("$ctx.")) == 0) {
		subname = name + strlen("$ctx.");
	} else {
		subname = name;
	}
	for (i = 0; i < ctx->nr_fields; i++) {
		/* Skip allocated (but non-initialized) contexts */
		if (!ctx->fields[i].event_field.name)
			continue;
		if (!strcmp(ctx->fields[i].event_field.name, subname))
			return i;
	}
	return -1;
}

static int lttng_find_context_provider(struct lttng_ctx *ctx, const char *name)
{
	unsigned int i;

	for (i = 0; i < ctx->nr_fields; i++) {
		/* Skip allocated (but non-initialized) contexts */
		if (!ctx->fields[i].event_field.name)
			continue;
		if (!strncmp(ctx->fields[i].event_field.name, name,
				strlen(name)))
			return 1;
	}
	return 0;
}

/*
 * Note: as we append context information, the pointer location may change.
 */
struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p)
{
	struct lttng_ctx_field *field;
	struct lttng_ctx *ctx;

	if (!*ctx_p) {
		*ctx_p = zmalloc(sizeof(struct lttng_ctx));
		if (!*ctx_p)
			return NULL;
		(*ctx_p)->largest_align = 1;
	}
	ctx = *ctx_p;
	if (ctx->nr_fields + 1 > ctx->allocated_fields) {
		struct lttng_ctx_field *new_fields;

		ctx->allocated_fields = max_t(size_t, 1, 2 * ctx->allocated_fields);
		new_fields = zmalloc(ctx->allocated_fields * sizeof(struct lttng_ctx_field));
		if (!new_fields)
			return NULL;
		if (ctx->fields)
			memcpy(new_fields, ctx->fields, sizeof(*ctx->fields) * ctx->nr_fields);
		free(ctx->fields);
		ctx->fields = new_fields;
	}
	field = &ctx->fields[ctx->nr_fields];
	ctx->nr_fields++;
	return field;
}

int lttng_context_add_rcu(struct lttng_ctx **ctx_p,
		const struct lttng_ctx_field *f)
{
	struct lttng_ctx *old_ctx = *ctx_p, *new_ctx = NULL;
	struct lttng_ctx_field *new_fields = NULL;
	struct lttng_ctx_field *nf;

	if (old_ctx) {
		new_ctx = zmalloc(sizeof(struct lttng_ctx));
		if (!new_ctx)
			return -ENOMEM;
		*new_ctx = *old_ctx;
		new_fields = zmalloc(new_ctx->allocated_fields
				* sizeof(struct lttng_ctx_field));
		if (!new_fields) {
			free(new_ctx);
			return -ENOMEM;
		}
		memcpy(new_fields, old_ctx->fields,
				sizeof(*old_ctx->fields) * old_ctx->nr_fields);
		new_ctx->fields = new_fields;
	}
	nf = lttng_append_context(&new_ctx);
	if (!nf) {
		free(new_fields);
		free(new_ctx);
		return -ENOMEM;
	}
	*nf = *f;
	lttng_context_update(new_ctx);
	rcu_assign_pointer(*ctx_p, new_ctx);
	synchronize_trace();
	if (old_ctx) {
		free(old_ctx->fields);
		free(old_ctx);
	}
	return 0;
}

/*
 * lttng_context_update() should be called at least once between context
 * modification and trace start.
 */
void lttng_context_update(struct lttng_ctx *ctx)
{
	int i;
	size_t largest_align = 8;	/* in bits */

	for (i = 0; i < ctx->nr_fields; i++) {
		struct lttng_type *type;
		size_t field_align = 8;

		type = &ctx->fields[i].event_field.type;
		switch (type->atype) {
		case atype_integer:
			field_align = type->u.basic.integer.alignment;
			break;
		case atype_array:
		{
			struct lttng_basic_type *btype;

			btype = &type->u.array.elem_type;
			switch (btype->atype) {
			case atype_integer:
				field_align = btype->u.basic.integer.alignment;
				break;
			case atype_string:
				break;

			case atype_array:
			case atype_sequence:
			default:
				WARN_ON_ONCE(1);
				break;
			}
			break;
		}
		case atype_sequence:
		{
			struct lttng_basic_type *btype;

			btype = &type->u.sequence.length_type;
			switch (btype->atype) {
			case atype_integer:
				field_align = btype->u.basic.integer.alignment;
				break;

			case atype_string:
			case atype_array:
			case atype_sequence:
			default:
				WARN_ON_ONCE(1);
				break;
			}

			btype = &type->u.sequence.elem_type;
			switch (btype->atype) {
			case atype_integer:
				field_align = max_t(size_t,
					field_align,
					btype->u.basic.integer.alignment);
				break;

			case atype_string:
				break;

			case atype_array:
			case atype_sequence:
			default:
				WARN_ON_ONCE(1);
				break;
			}
			break;
		}
		case atype_string:
			break;
		case atype_dynamic:
			break;
		case atype_enum:
		default:
			WARN_ON_ONCE(1);
			break;
		}
		largest_align = max_t(size_t, largest_align, field_align);
	}
	ctx->largest_align = largest_align >> 3;	/* bits to bytes */
}

/*
 * Remove last context field.
 */
void lttng_remove_context_field(struct lttng_ctx **ctx_p,
				struct lttng_ctx_field *field)
{
	struct lttng_ctx *ctx;

	ctx = *ctx_p;
	ctx->nr_fields--;
	assert(&ctx->fields[ctx->nr_fields] == field);
	assert(field->field_name == NULL);
	memset(&ctx->fields[ctx->nr_fields], 0, sizeof(struct lttng_ctx_field));
}

void lttng_destroy_context(struct lttng_ctx *ctx)
{
	int i;

	if (!ctx)
		return;
	for (i = 0; i < ctx->nr_fields; i++) {
		if (ctx->fields[i].destroy)
			ctx->fields[i].destroy(&ctx->fields[i]);
		free(ctx->fields[i].field_name);
	}
	free(ctx->fields);
	free(ctx);
}

/*
 * Can be safely performed concurrently with tracing using the struct
 * lttng_ctx. Using RCU update. Needs to match RCU read-side handling of
 * contexts.
 *
 * This does not allow adding, removing, or changing typing of the
 * contexts, since this needs to stay invariant for metadata. However,
 * it allows updating the handlers associated with all contexts matching
 * a provider (by name) while tracing is using it, in a way that ensures
 * a single RCU read-side critical section see either all old, or all
 * new handlers.
 */
int lttng_ust_context_set_provider_rcu(struct lttng_ctx **_ctx,
		const char *name,
		size_t (*get_size)(struct lttng_ctx_field *field, size_t offset),
		void (*record)(struct lttng_ctx_field *field,
			struct lttng_ust_lib_ring_buffer_ctx *ctx,
			struct lttng_channel *chan),
		void (*get_value)(struct lttng_ctx_field *field,
			struct lttng_ctx_value *value))
{
	int i, ret;
	struct lttng_ctx *ctx = *_ctx, *new_ctx;
	struct lttng_ctx_field *new_fields;

	if (!ctx || !lttng_find_context_provider(ctx, name))
		return 0;
	/*
	 * We have at least one instance of context for the provider.
	 */
	new_ctx = zmalloc(sizeof(*new_ctx));
	if (!new_ctx)
		return -ENOMEM;
	*new_ctx = *ctx;
	new_fields = zmalloc(sizeof(*new_fields) * ctx->allocated_fields);
	if (!new_fields) {
		ret = -ENOMEM;
		goto field_error;
	}
	memcpy(new_fields, ctx->fields,
		sizeof(*new_fields) * ctx->allocated_fields);
	for (i = 0; i < ctx->nr_fields; i++) {
		if (strncmp(new_fields[i].event_field.name,
				name, strlen(name)) != 0)
			continue;
		new_fields[i].get_size = get_size;
		new_fields[i].record = record;
		new_fields[i].get_value = get_value;
	}
	new_ctx->fields = new_fields;
	rcu_assign_pointer(*_ctx, new_ctx);
	synchronize_trace();
	free(ctx->fields);
	free(ctx);
	return 0;

field_error:
	free(new_ctx);
	return ret;
}

int lttng_session_context_init(struct lttng_ctx **ctx)
{
	int ret;

	ret = lttng_add_pthread_id_to_ctx(ctx);
	if (ret) {
		WARN("Cannot add context lttng_add_pthread_id_to_ctx");
		goto error;
	}
	ret = lttng_add_vtid_to_ctx(ctx);
	if (ret) {
		WARN("Cannot add context lttng_add_vtid_to_ctx");
		goto error;
	}
	ret = lttng_add_vpid_to_ctx(ctx);
	if (ret) {
		WARN("Cannot add context lttng_add_vpid_to_ctx");
		goto error;
	}
	ret = lttng_add_procname_to_ctx(ctx);
	if (ret) {
		WARN("Cannot add context lttng_add_procname_to_ctx");
		goto error;
	}
	ret = lttng_add_cpu_id_to_ctx(ctx);
	if (ret) {
		WARN("Cannot add context lttng_add_cpu_id_to_ctx");
		goto error;
	}
	lttng_context_update(*ctx);
	return 0;

error:
	lttng_destroy_context(*ctx);
	return ret;
}

/* For backward compatibility. Leave those exported symbols in place. */
struct lttng_ctx *lttng_static_ctx;

void lttng_context_init(void)
{
}

void lttng_context_exit(void)
{
}
Commit	Line	Data
8020ceb5	1	/*
e92f3e28	2	* lttng-context.c
8020ceb5	3	*
8173ec7c	4	* LTTng UST trace/channel/event context management.
8020ceb5	5	*
e92f3e28 MD	6	* Copyright (C) 2011 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
8020ceb5 MD	21	*/
8020ceb5 MD	22
e92f3e28	23
4318ae1b MD	24	#include <lttng/ust-events.h>
4318ae1b MD	25	#include <lttng/ust-tracer.h>
53569322 MD	26	#include <lttng/ust-context-provider.h>
53569322 MD	27	#include <urcu-pointer.h>
a0a3bef9	28	#include <usterr-signal-safe.h>
35897f8b	29	#include <helper.h>
8d8a24c8	30	#include <string.h>
8173ec7c MD	31	#include <assert.h>
8173ec7c MD	32
77aa5901 MD	33	/*
	34	* The filter implementation requires that two consecutive "get" for the
	35	* same context performed by the same thread return the same result.
	36	*/
	37
8173ec7c MD	38	int lttng_find_context(struct lttng_ctx ctx, const char name)
	39	{
	40	unsigned int i;
53569322	41	const char *subname;
8173ec7c	42
53569322 MD	43	if (strncmp(name, "$ctx.", strlen("$ctx.")) == 0) {
	44	subname = name + strlen("$ctx.");
	45	} else {
	46	subname = name;
	47	}
8173ec7c MD	48	for (i = 0; i < ctx->nr_fields; i++) {
	49	/* Skip allocated (but non-initialized) contexts */
	50	if (!ctx->fields[i].event_field.name)
	51	continue;
53569322	52	if (!strcmp(ctx->fields[i].event_field.name, subname))
8173ec7c MD	53	return 1;
	54	}
	55	return 0;
	56	}
8020ceb5	57
77aa5901 MD	58	int lttng_get_context_index(struct lttng_ctx ctx, const char name)
	59	{
	60	unsigned int i;
53569322	61	const char *subname;
77aa5901 MD	62
	63	if (!ctx)
	64	return -1;
53569322 MD	65	if (strncmp(name, "$ctx.", strlen("$ctx.")) == 0) {
	66	subname = name + strlen("$ctx.");
	67	} else {
	68	subname = name;
	69	}
77aa5901 MD	70	for (i = 0; i < ctx->nr_fields; i++) {
	71	/* Skip allocated (but non-initialized) contexts */
	72	if (!ctx->fields[i].event_field.name)
	73	continue;
53569322	74	if (!strcmp(ctx->fields[i].event_field.name, subname))
77aa5901 MD	75	return i;
	76	}
	77	return -1;
	78	}
	79
53569322 MD	80	static int lttng_find_context_provider(struct lttng_ctx ctx, const char name)
	81	{
	82	unsigned int i;
	83
	84	for (i = 0; i < ctx->nr_fields; i++) {
	85	/* Skip allocated (but non-initialized) contexts */
	86	if (!ctx->fields[i].event_field.name)
	87	continue;
	88	if (!strncmp(ctx->fields[i].event_field.name, name,
	89	strlen(name)))
	90	return 1;
	91	}
	92	return 0;
	93	}
	94
a0a748b8 MD	95	/*
	96	* Note: as we append context information, the pointer location may change.
	97	*/
8020ceb5 MD	98	struct lttng_ctx_field lttng_append_context(struct lttng_ctx *ctx_p)
	99	{
	100	struct lttng_ctx_field *field;
	101	struct lttng_ctx *ctx;
	102
	103	if (!*ctx_p) {
8d8a24c8	104	*ctx_p = zmalloc(sizeof(struct lttng_ctx));
8020ceb5 MD	105	if (!*ctx_p)
8020ceb5 MD	106	return NULL;
b2cc986a	107	(*ctx_p)->largest_align = 1;
8020ceb5 MD	108	}
	109	ctx = *ctx_p;
	110	if (ctx->nr_fields + 1 > ctx->allocated_fields) {
	111	struct lttng_ctx_field *new_fields;
	112
	113	ctx->allocated_fields = max_t(size_t, 1, 2 * ctx->allocated_fields);
8d8a24c8	114	new_fields = zmalloc(ctx->allocated_fields * sizeof(struct lttng_ctx_field));
8020ceb5 MD	115	if (!new_fields)
	116	return NULL;
	117	if (ctx->fields)
	118	memcpy(new_fields, ctx->fields, sizeof(ctx->fields) ctx->nr_fields);
8d8a24c8	119	free(ctx->fields);
8020ceb5 MD	120	ctx->fields = new_fields;
	121	}
	122	field = &ctx->fields[ctx->nr_fields];
	123	ctx->nr_fields++;
	124	return field;
	125	}
8020ceb5	126
53569322 MD	127	int lttng_context_add_rcu(struct lttng_ctx **ctx_p,
	128	const struct lttng_ctx_field *f)
	129	{
	130	struct lttng_ctx old_ctx = ctx_p, *new_ctx = NULL;
	131	struct lttng_ctx_field *new_fields = NULL;
	132	struct lttng_ctx_field *nf;
	133
	134	if (old_ctx) {
	135	new_ctx = zmalloc(sizeof(struct lttng_ctx));
	136	if (!new_ctx)
	137	return -ENOMEM;
	138	new_ctx = old_ctx;
	139	new_fields = zmalloc(new_ctx->allocated_fields
	140	* sizeof(struct lttng_ctx_field));
	141	if (!new_fields) {
	142	free(new_ctx);
	143	return -ENOMEM;
	144	}
	145	memcpy(new_fields, old_ctx->fields,
	146	sizeof(old_ctx->fields) old_ctx->nr_fields);
	147	new_ctx->fields = new_fields;
	148	}
	149	nf = lttng_append_context(&new_ctx);
	150	if (!nf) {
	151	free(new_fields);
	152	free(new_ctx);
	153	return -ENOMEM;
	154	}
	155	nf = f;
	156	lttng_context_update(new_ctx);
	157	rcu_assign_pointer(*ctx_p, new_ctx);
	158	synchronize_trace();
	159	if (old_ctx) {
	160	free(old_ctx->fields);
	161	free(old_ctx);
	162	}
	163	return 0;
	164	}
	165
b2cc986a MD	166	/*
	167	* lttng_context_update() should be called at least once between context
	168	* modification and trace start.
	169	*/
	170	void lttng_context_update(struct lttng_ctx *ctx)
	171	{
	172	int i;
	173	size_t largest_align = 8; /* in bits */
	174
	175	for (i = 0; i < ctx->nr_fields; i++) {
	176	struct lttng_type *type;
	177	size_t field_align = 8;
	178
	179	type = &ctx->fields[i].event_field.type;
	180	switch (type->atype) {
	181	case atype_integer:
	182	field_align = type->u.basic.integer.alignment;
	183	break;
	184	case atype_array:
	185	{
	186	struct lttng_basic_type *btype;
	187
	188	btype = &type->u.array.elem_type;
	189	switch (btype->atype) {
	190	case atype_integer:
	191	field_align = btype->u.basic.integer.alignment;
	192	break;
	193	case atype_string:
	194	break;
	195
	196	case atype_array:
	197	case atype_sequence:
	198	default:
	199	WARN_ON_ONCE(1);
	200	break;
	201	}
	202	break;
	203	}
	204	case atype_sequence:
	205	{
	206	struct lttng_basic_type *btype;
	207
	208	btype = &type->u.sequence.length_type;
	209	switch (btype->atype) {
	210	case atype_integer:
	211	field_align = btype->u.basic.integer.alignment;
	212	break;
	213
	214	case atype_string:
	215	case atype_array:
	216	case atype_sequence:
	217	default:
	218	WARN_ON_ONCE(1);
	219	break;
	220	}
	221
	222	btype = &type->u.sequence.elem_type;
	223	switch (btype->atype) {
	224	case atype_integer:
	225	field_align = max_t(size_t,
	226	field_align,
	227	btype->u.basic.integer.alignment);
	228	break;
	229
230	case atype_string:
231	break;
232
233	case atype_array:
234	case atype_sequence:
235	default:
236	WARN_ON_ONCE(1);
237	break;
238	}
239	break;
240	}
241	case atype_string:
242	break;
53569322 MD	243	case atype_dynamic:
53569322 MD	244	break;
b2cc986a MD	245	case atype_enum:
	246	default:
	247	WARN_ON_ONCE(1);
	248	break;
	249	}
	250	largest_align = max_t(size_t, largest_align, field_align);
	251	}
	252	ctx->largest_align = largest_align >> 3; /* bits to bytes */
	253	}
	254
b13d13b1 MD	255	/*
	256	* Remove last context field.
	257	*/
8020ceb5 MD	258	void lttng_remove_context_field(struct lttng_ctx **ctx_p,
	259	struct lttng_ctx_field *field)
	260	{
	261	struct lttng_ctx *ctx;
	262
	263	ctx = *ctx_p;
	264	ctx->nr_fields--;
8173ec7c	265	assert(&ctx->fields[ctx->nr_fields] == field);
53569322	266	assert(field->field_name == NULL);
8020ceb5 MD	267	memset(&ctx->fields[ctx->nr_fields], 0, sizeof(struct lttng_ctx_field));
8020ceb5 MD	268	}
8020ceb5 MD	269
	270	void lttng_destroy_context(struct lttng_ctx *ctx)
	271	{
	272	int i;
	273
	274	if (!ctx)
	275	return;
	276	for (i = 0; i < ctx->nr_fields; i++) {
	277	if (ctx->fields[i].destroy)
	278	ctx->fields[i].destroy(&ctx->fields[i]);
53569322	279	free(ctx->fields[i].field_name);
8020ceb5	280	}
8d8a24c8 MD	281	free(ctx->fields);
8d8a24c8 MD	282	free(ctx);
8020ceb5	283	}
a0a3bef9	284
53569322 MD	285	/*
	286	* Can be safely performed concurrently with tracing using the struct
	287	* lttng_ctx. Using RCU update. Needs to match RCU read-side handling of
	288	* contexts.
	289	*
	290	* This does not allow adding, removing, or changing typing of the
	291	* contexts, since this needs to stay invariant for metadata. However,
	292	* it allows updating the handlers associated with all contexts matching
	293	* a provider (by name) while tracing is using it, in a way that ensures
	294	* a single RCU read-side critical section see either all old, or all
	295	* new handlers.
	296	*/
	297	int lttng_ust_context_set_provider_rcu(struct lttng_ctx **_ctx,
	298	const char *name,
	299	size_t (get_size)(struct lttng_ctx_field field, size_t offset),
	300	void (record)(struct lttng_ctx_field field,
	301	struct lttng_ust_lib_ring_buffer_ctx *ctx,
	302	struct lttng_channel *chan),
	303	void (get_value)(struct lttng_ctx_field field,
	304	struct lttng_ctx_value *value))
	305	{
	306	int i, ret;
	307	struct lttng_ctx ctx = _ctx, *new_ctx;
	308	struct lttng_ctx_field *new_fields;
	309
	310	if (!ctx \|\| !lttng_find_context_provider(ctx, name))
	311	return 0;
	312	/*
	313	* We have at least one instance of context for the provider.
	314	*/
	315	new_ctx = zmalloc(sizeof(*new_ctx));
	316	if (!new_ctx)
	317	return -ENOMEM;
	318	new_ctx = ctx;
	319	new_fields = zmalloc(sizeof(new_fields) ctx->allocated_fields);
	320	if (!new_fields) {
	321	ret = -ENOMEM;
	322	goto field_error;
	323	}
	324	memcpy(new_fields, ctx->fields,
	325	sizeof(new_fields) ctx->allocated_fields);
	326	for (i = 0; i < ctx->nr_fields; i++) {
	327	if (strncmp(new_fields[i].event_field.name,
	328	name, strlen(name)) != 0)
	329	continue;
	330	new_fields[i].get_size = get_size;
	331	new_fields[i].record = record;
	332	new_fields[i].get_value = get_value;
	333	}
	334	new_ctx->fields = new_fields;
	335	rcu_assign_pointer(*_ctx, new_ctx);
	336	synchronize_trace();
	337	free(ctx->fields);
	338	free(ctx);
	339	return 0;
	340
	341	field_error:
	342	free(new_ctx);
	343	return ret;
	344	}
	345
	346	int lttng_session_context_init(struct lttng_ctx **ctx)
a0a3bef9 MD	347	{
	348	int ret;
	349
53569322	350	ret = lttng_add_pthread_id_to_ctx(ctx);
a0a3bef9 MD	351	if (ret) {
a0a3bef9 MD	352	WARN("Cannot add context lttng_add_pthread_id_to_ctx");
53569322	353	goto error;
a0a3bef9	354	}
53569322	355	ret = lttng_add_vtid_to_ctx(ctx);
a0a3bef9 MD	356	if (ret) {
a0a3bef9 MD	357	WARN("Cannot add context lttng_add_vtid_to_ctx");
53569322	358	goto error;
a0a3bef9	359	}
53569322	360	ret = lttng_add_vpid_to_ctx(ctx);
a0a3bef9 MD	361	if (ret) {
a0a3bef9 MD	362	WARN("Cannot add context lttng_add_vpid_to_ctx");
53569322	363	goto error;
a0a3bef9	364	}
53569322	365	ret = lttng_add_procname_to_ctx(ctx);
a0a3bef9 MD	366	if (ret) {
a0a3bef9 MD	367	WARN("Cannot add context lttng_add_procname_to_ctx");
53569322	368	goto error;
a0a3bef9	369	}
53569322	370	ret = lttng_add_cpu_id_to_ctx(ctx);
c7ea8487 MD	371	if (ret) {
c7ea8487 MD	372	WARN("Cannot add context lttng_add_cpu_id_to_ctx");
53569322	373	goto error;
c7ea8487	374	}
53569322 MD	375	lttng_context_update(*ctx);
53569322 MD	376	return 0;
a0a3bef9	377
53569322 MD	378	error:
	379	lttng_destroy_context(*ctx);
	380	return ret;
a0a3bef9	381	}
4a1f7569 MD	382
	383	/* For backward compatibility. Leave those exported symbols in place. */
	384	struct lttng_ctx *lttng_static_ctx;
	385
	386	void lttng_context_init(void)
	387	{
	388	}
	389
	390	void lttng_context_exit(void)
	391	{
	392	}