[lttng-tools.git] / src / bin / lttng-sessiond / context.c

/*
 * Copyright (C)  2011 - David Goulet <david.goulet@polymtl.ca>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <urcu/list.h>

#include <common/error.h>
#include <common/sessiond-comm/sessiond-comm.h>

#include "context.h"
#include "kernel.h"
#include "ust-app.h"
#include "trace-ust.h"

/*
 * Add kernel context to an event of a specific channel.
 */
static int add_kctx_to_event(struct lttng_kernel_context *kctx,
		struct ltt_kernel_channel *kchan, char *event_name)
{
	int ret, found = 0;
	struct ltt_kernel_event *kevent;

	DBG("Add kernel context to event %s", event_name);

	kevent = trace_kernel_get_event_by_name(event_name, kchan);
	if (kevent != NULL) {
		ret = kernel_add_event_context(kevent, kctx);
		if (ret < 0) {
			goto error;
		}
		found = 1;
	}

	ret = found;

error:
	return ret;
}

/*
 * Add kernel context to all channel.
 *
 * If event_name is specified, add context to event instead.
 */
static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
		struct lttng_kernel_context *kctx, char *event_name)
{
	int ret, no_event = 0, found = 0;
	struct ltt_kernel_channel *kchan;

	if (strlen(event_name) == 0) {
		no_event = 1;
	}

	DBG("Adding kernel context to all channels (event: %s)", event_name);

	/* Go over all channels */
	cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
		if (no_event) {
			ret = kernel_add_channel_context(kchan, kctx);
			if (ret < 0) {
				ret = LTTCOMM_KERN_CONTEXT_FAIL;
				goto error;
			}
		} else {
			ret = add_kctx_to_event(kctx, kchan, event_name);
			if (ret < 0) {
				ret = LTTCOMM_KERN_CONTEXT_FAIL;
				goto error;
			} else if (ret == 1) {
				/* Event found and context added */
				found = 1;
				break;
			}
		}
	}

	if (!found && !no_event) {
		ret = LTTCOMM_NO_EVENT;
		goto error;
	}

	ret = LTTCOMM_OK;

error:
	return ret;
}

/*
 * Add kernel context to a specific channel.
 *
 * If event_name is specified, add context to that event.
 */
static int add_kctx_to_channel(struct lttng_kernel_context *kctx,
		struct ltt_kernel_channel *kchan, char *event_name)
{
	int ret, no_event = 0, found = 0;

	if (strlen(event_name) == 0) {
		no_event = 1;
	}

	DBG("Add kernel context to channel '%s', event '%s'",
			kchan->channel->name, event_name);

	if (no_event) {
		ret = kernel_add_channel_context(kchan, kctx);
		if (ret < 0) {
			ret = LTTCOMM_KERN_CONTEXT_FAIL;
			goto error;
		}
	} else {
		ret = add_kctx_to_event(kctx, kchan, event_name);
		if (ret < 0) {
			ret = LTTCOMM_KERN_CONTEXT_FAIL;
			goto error;
		} else if (ret == 1) {
			/* Event found and context added */
			found = 1;
		}
	}

	if (!found && !no_event) {
		ret = LTTCOMM_NO_EVENT;
		goto error;
	}

	ret = LTTCOMM_OK;

error:
	return ret;
}

/*
 * Add UST context to channel.
 */
static int add_uctx_to_channel(struct ltt_ust_session *usess, int domain,
		struct ltt_ust_channel *uchan, struct lttng_event_context *ctx)
{
	int ret;
	struct ltt_ust_context *uctx;
	struct lttng_ht_iter iter;
	struct lttng_ht_node_ulong *uctx_node;

	/* Create ltt UST context */
	uctx = trace_ust_create_context(ctx);
	if (uctx == NULL) {
		ret = -EINVAL;
		goto error;
	}

	switch (domain) {
	case LTTNG_DOMAIN_UST:
		ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
		if (ret < 0) {
			goto error;
		}
		break;
	default:
		ret = -ENOSYS;
		goto error;
	}

	/* Lookup context before adding it */
	lttng_ht_lookup(uchan->ctx, (void *)((unsigned long)uctx->ctx.ctx), &iter);
	uctx_node = lttng_ht_iter_get_node_ulong(&iter);
	if (uctx_node != NULL) {
		ret = -EEXIST;
		goto error;
	}

	/* Add ltt UST context node to ltt UST channel */
	lttng_ht_add_unique_ulong(uchan->ctx, &uctx->node);

	DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);

	return 0;

error:
	free(uctx);
	return ret;
}

/*
 * Add UST context to event.
 */
static int add_uctx_to_event(struct ltt_ust_session *usess, int domain,
		struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent,
		struct lttng_event_context *ctx)
{
	int ret;
	struct ltt_ust_context *uctx;
	struct lttng_ht_iter iter;
	struct lttng_ht_node_ulong *uctx_node;

	/* Create ltt UST context */
	uctx = trace_ust_create_context(ctx);
	if (uctx == NULL) {
		/* Context values are invalid. */
		ret = -EINVAL;
		goto error;
	}

	switch (domain) {
	case LTTNG_DOMAIN_UST:
		ret = ust_app_add_ctx_event_glb(usess, uchan, uevent, uctx);
		if (ret < 0) {
			goto error;
		}
		break;
	default:
		ret = -ENOSYS;
		goto error;
	}

	/* Lookup context before adding it */
	lttng_ht_lookup(uevent->ctx, (void *)((unsigned long)uctx->ctx.ctx), &iter);
	uctx_node = lttng_ht_iter_get_node_ulong(&iter);
	if (uctx_node != NULL) {
		ret = -EEXIST;
		goto error;
	}

	/* Add ltt UST context node to ltt UST event */
	lttng_ht_add_unique_ulong(uevent->ctx, &uctx->node);

	DBG("Context UST %d added to event %s", uctx->ctx.ctx, uevent->attr.name);

	return 0;

error:
	free(uctx);
	return ret;
}

/*
 * Add kernel context to tracer.
 */
int context_kernel_add(struct ltt_kernel_session *ksession,
		struct lttng_event_context *ctx, char *event_name,
		char *channel_name)
{
	int ret;
	struct ltt_kernel_channel *kchan;
	struct lttng_kernel_context kctx;

	/* Setup kernel context structure */
	switch (ctx->ctx) {
	case LTTNG_EVENT_CONTEXT_PID:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
		break;
	case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_COUNTER;
		break;
	case LTTNG_EVENT_CONTEXT_PROCNAME:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
		break;
	case LTTNG_EVENT_CONTEXT_PRIO:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
		break;
	case LTTNG_EVENT_CONTEXT_NICE:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
		break;
	case LTTNG_EVENT_CONTEXT_VPID:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
		break;
	case LTTNG_EVENT_CONTEXT_TID:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
		break;
	case LTTNG_EVENT_CONTEXT_VTID:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
		break;
	case LTTNG_EVENT_CONTEXT_PPID:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
		break;
	case LTTNG_EVENT_CONTEXT_VPPID:
		kctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
		break;
	default:
		return LTTCOMM_KERN_CONTEXT_FAIL;
	}

	kctx.u.perf_counter.type = ctx->u.perf_counter.type;
	kctx.u.perf_counter.config = ctx->u.perf_counter.config;
	strncpy(kctx.u.perf_counter.name, ctx->u.perf_counter.name,
			LTTNG_SYMBOL_NAME_LEN);
	kctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';

	if (strlen(channel_name) == 0) {
		ret = add_kctx_all_channels(ksession, &kctx, event_name);
		if (ret != LTTCOMM_OK) {
			goto error;
		}
	} else {
		/* Get kernel channel */
		kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
		if (kchan == NULL) {
			ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
			goto error;
		}

		ret = add_kctx_to_channel(&kctx, kchan, event_name);
		if (ret != LTTCOMM_OK) {
			goto error;
		}
	}

	ret = LTTCOMM_OK;

error:
	return ret;
}

/*
 * Add UST context to tracer.
 */
int context_ust_add(struct ltt_ust_session *usess, int domain,
		struct lttng_event_context *ctx, char *event_name,
		char *channel_name)
{
	int ret = LTTCOMM_OK, have_event = 0;
	struct lttng_ht_iter iter;
	struct lttng_ht *chan_ht;
	struct ltt_ust_channel *uchan = NULL;
	struct ltt_ust_event *uevent = NULL;

	/*
	 * Define which channel's hashtable to use from the domain or quit if
	 * unknown domain.
	 */
	switch (domain) {
	case LTTNG_DOMAIN_UST:
		chan_ht = usess->domain_global.channels;
		break;
#if 0
	case LTTNG_DOMAIN_UST_EXEC_NAME:
	case LTTNG_DOMAIN_UST_PID:
	case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
#endif
	default:
		ret = LTTCOMM_UND;
		goto error;
	}

	/* Do we have an event name */
	if (strlen(event_name) != 0) {
		have_event = 1;
	}

	/* Get UST channel if defined */
	if (strlen(channel_name) != 0) {
		uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
		if (uchan == NULL) {
			ret = LTTCOMM_UST_CHAN_NOT_FOUND;
			goto error;
		}
	}

	/* If UST channel specified and event name, get UST event ref */
	if (uchan && have_event) {
		uevent = trace_ust_find_event_by_name(uchan->events, event_name);
		if (uevent == NULL) {
			ret = LTTCOMM_UST_EVENT_NOT_FOUND;
			goto error;
		}
	}

	/* At this point, we have 4 possibilities */

	if (uchan && uevent) {				/* Add ctx to event in channel */
		ret = add_uctx_to_event(usess, domain, uchan, uevent, ctx);
	} else if (uchan && !have_event) {	/* Add ctx to channel */
		ret = add_uctx_to_channel(usess, domain, uchan, ctx);
	} else if (!uchan && have_event) {	/* Add ctx to event */
		/* Add context to event without having the channel name */
		cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
			uevent = trace_ust_find_event_by_name(uchan->events, event_name);
			if (uevent != NULL) {
				ret = add_uctx_to_event(usess, domain, uchan, uevent, ctx);
				/*
				 * LTTng UST does not allowed the same event to be registered
				 * multiple time in different or the same channel. So, if we
				 * found our event, we stop.
				 */
				goto end;
			}
		}
		ret = LTTCOMM_UST_EVENT_NOT_FOUND;
		goto error;
	} else if (!uchan && !have_event) {	/* Add ctx all events, all channels */
		/* For all channels */
		cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
			ret = add_uctx_to_channel(usess, domain, uchan, ctx);
			if (ret < 0) {
				ERR("Context failed for channel %s", uchan->name);
				continue;
			}
		}
	}

end:
	switch (ret) {
	case -EEXIST:
		ret = LTTCOMM_UST_CONTEXT_EXIST;
		break;
	case -ENOMEM:
		ret = LTTCOMM_FATAL;
		break;
	case -EINVAL:
		ret = LTTCOMM_UST_CONTEXT_INVAL;
		break;
	case -ENOSYS:
		ret = LTTCOMM_UNKNOWN_DOMAIN;
		break;
	default:
		ret = LTTCOMM_OK;
		break;
	}

error:
	return ret;
}
Commit	Line	Data
b579acd9 DG	1	/*
	2	* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
	3	*
d14d33bf AM	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License, version 2 only,
	6	* as published by the Free Software Foundation.
b579acd9	7	*
d14d33bf AM	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
b579acd9	12	*
d14d33bf AM	13	* You should have received a copy of the GNU General Public License along
	14	* with this program; if not, write to the Free Software Foundation, Inc.,
	15	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
b579acd9 DG	16	*/
	17
	18	#define _GNU_SOURCE
	19	#include <stdio.h>
	20	#include <stdlib.h>
	21	#include <string.h>
	22	#include <unistd.h>
54d01ffb	23	#include <urcu/list.h>
1e307fab	24
db758600	25	#include <common/error.h>
10a8a223	26	#include <common/sessiond-comm/sessiond-comm.h>
b579acd9	27
b579acd9	28	#include "context.h"
4771f025	29	#include "kernel.h"
55cc08a6	30	#include "ust-app.h"
34378f76	31	#include "trace-ust.h"
b579acd9 DG	32
	33	/*
	34	* Add kernel context to an event of a specific channel.
	35	*/
	36	static int add_kctx_to_event(struct lttng_kernel_context *kctx,
	37	struct ltt_kernel_channel kchan, char event_name)
	38	{
	39	int ret, found = 0;
	40	struct ltt_kernel_event *kevent;
	41
	42	DBG("Add kernel context to event %s", event_name);
	43
62499ad6	44	kevent = trace_kernel_get_event_by_name(event_name, kchan);
b579acd9 DG	45	if (kevent != NULL) {
	46	ret = kernel_add_event_context(kevent, kctx);
	47	if (ret < 0) {
	48	goto error;
	49	}
	50	found = 1;
	51	}
	52
	53	ret = found;
	54
	55	error:
	56	return ret;
	57	}
	58
	59	/*
	60	* Add kernel context to all channel.
	61	*
	62	* If event_name is specified, add context to event instead.
	63	*/
	64	static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
	65	struct lttng_kernel_context kctx, char event_name)
	66	{
	67	int ret, no_event = 0, found = 0;
	68	struct ltt_kernel_channel *kchan;
	69
	70	if (strlen(event_name) == 0) {
	71	no_event = 1;
	72	}
	73
	74	DBG("Adding kernel context to all channels (event: %s)", event_name);
	75
	76	/* Go over all channels */
	77	cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
	78	if (no_event) {
	79	ret = kernel_add_channel_context(kchan, kctx);
	80	if (ret < 0) {
	81	ret = LTTCOMM_KERN_CONTEXT_FAIL;
	82	goto error;
	83	}
	84	} else {
	85	ret = add_kctx_to_event(kctx, kchan, event_name);
	86	if (ret < 0) {
	87	ret = LTTCOMM_KERN_CONTEXT_FAIL;
	88	goto error;
	89	} else if (ret == 1) {
	90	/* Event found and context added */
	91	found = 1;
	92	break;
	93	}
	94	}
	95	}
	96
	97	if (!found && !no_event) {
	98	ret = LTTCOMM_NO_EVENT;
	99	goto error;
	100	}
	101
	102	ret = LTTCOMM_OK;
	103
	104	error:
	105	return ret;
	106	}
	107
	108	/*
109	* Add kernel context to a specific channel.
110	*
111	* If event_name is specified, add context to that event.
112	*/
113	static int add_kctx_to_channel(struct lttng_kernel_context *kctx,
114	struct ltt_kernel_channel kchan, char event_name)
115	{
116	int ret, no_event = 0, found = 0;
117
118	if (strlen(event_name) == 0) {
119	no_event = 1;
120	}
121
122	DBG("Add kernel context to channel '%s', event '%s'",
123	kchan->channel->name, event_name);
124
125	if (no_event) {
126	ret = kernel_add_channel_context(kchan, kctx);
127	if (ret < 0) {
128	ret = LTTCOMM_KERN_CONTEXT_FAIL;
129	goto error;
130	}
131	} else {
132	ret = add_kctx_to_event(kctx, kchan, event_name);
133	if (ret < 0) {
134	ret = LTTCOMM_KERN_CONTEXT_FAIL;
135	goto error;
136	} else if (ret == 1) {
137	/* Event found and context added */
138	found = 1;
139	}
140	}
141
142	if (!found && !no_event) {
143	ret = LTTCOMM_NO_EVENT;
144	goto error;
145	}
146
147	ret = LTTCOMM_OK;
148
149	error:
150	return ret;
151	}
152
6b79ed20 DG	153	/*
	154	* Add UST context to channel.
	155	*/
	156	static int add_uctx_to_channel(struct ltt_ust_session *usess, int domain,
	157	struct ltt_ust_channel uchan, struct lttng_event_context ctx)
	158	{
	159	int ret;
	160	struct ltt_ust_context *uctx;
727d5404 DG	161	struct lttng_ht_iter iter;
727d5404 DG	162	struct lttng_ht_node_ulong *uctx_node;
6b79ed20 DG	163
	164	/* Create ltt UST context */
	165	uctx = trace_ust_create_context(ctx);
	166	if (uctx == NULL) {
727d5404	167	ret = -EINVAL;
6b79ed20 DG	168	goto error;
	169	}
	170
	171	switch (domain) {
	172	case LTTNG_DOMAIN_UST:
	173	ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
	174	if (ret < 0) {
	175	goto error;
	176	}
	177	break;
	178	default:
727d5404 DG	179	ret = -ENOSYS;
	180	goto error;
	181	}
	182
	183	/* Lookup context before adding it */
	184	lttng_ht_lookup(uchan->ctx, (void *)((unsigned long)uctx->ctx.ctx), &iter);
	185	uctx_node = lttng_ht_iter_get_node_ulong(&iter);
	186	if (uctx_node != NULL) {
	187	ret = -EEXIST;
6b79ed20 DG	188	goto error;
	189	}
	190
	191	/* Add ltt UST context node to ltt UST channel */
bec39940	192	lttng_ht_add_unique_ulong(uchan->ctx, &uctx->node);
6b79ed20	193
727d5404 DG	194	DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
	195
	196	return 0;
6b79ed20 DG	197
	198	error:
	199	free(uctx);
	200	return ret;
	201	}
	202
	203	/*
	204	* Add UST context to event.
	205	*/
	206	static int add_uctx_to_event(struct ltt_ust_session *usess, int domain,
	207	struct ltt_ust_channel uchan, struct ltt_ust_event uevent,
	208	struct lttng_event_context *ctx)
	209	{
	210	int ret;
	211	struct ltt_ust_context *uctx;
727d5404 DG	212	struct lttng_ht_iter iter;
727d5404 DG	213	struct lttng_ht_node_ulong *uctx_node;
6b79ed20 DG	214
	215	/* Create ltt UST context */
	216	uctx = trace_ust_create_context(ctx);
	217	if (uctx == NULL) {
727d5404 DG	218	/* Context values are invalid. */
727d5404 DG	219	ret = -EINVAL;
6b79ed20 DG	220	goto error;
	221	}
	222
	223	switch (domain) {
	224	case LTTNG_DOMAIN_UST:
	225	ret = ust_app_add_ctx_event_glb(usess, uchan, uevent, uctx);
	226	if (ret < 0) {
	227	goto error;
	228	}
	229	break;
	230	default:
727d5404 DG	231	ret = -ENOSYS;
	232	goto error;
	233	}
	234
	235	/* Lookup context before adding it */
	236	lttng_ht_lookup(uevent->ctx, (void *)((unsigned long)uctx->ctx.ctx), &iter);
	237	uctx_node = lttng_ht_iter_get_node_ulong(&iter);
	238	if (uctx_node != NULL) {
	239	ret = -EEXIST;
6b79ed20 DG	240	goto error;
	241	}
	242
	243	/* Add ltt UST context node to ltt UST event */
bec39940	244	lttng_ht_add_unique_ulong(uevent->ctx, &uctx->node);
6b79ed20	245
727d5404 DG	246	DBG("Context UST %d added to event %s", uctx->ctx.ctx, uevent->attr.name);
	247
	248	return 0;
6b79ed20 DG	249
	250	error:
	251	free(uctx);
	252	return ret;
	253	}
	254
b579acd9 DG	255	/*
	256	* Add kernel context to tracer.
	257	*/
54d01ffb DG	258	int context_kernel_add(struct ltt_kernel_session *ksession,
54d01ffb DG	259	struct lttng_event_context ctx, char event_name,
b579acd9 DG	260	char *channel_name)
	261	{
	262	int ret;
	263	struct ltt_kernel_channel *kchan;
54d01ffb DG	264	struct lttng_kernel_context kctx;
	265
	266	/* Setup kernel context structure */
9197c5c4 MD	267	switch (ctx->ctx) {
	268	case LTTNG_EVENT_CONTEXT_PID:
	269	kctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
	270	break;
	271	case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
	272	kctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_COUNTER;
	273	break;
	274	case LTTNG_EVENT_CONTEXT_PROCNAME:
	275	kctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
	276	break;
	277	case LTTNG_EVENT_CONTEXT_PRIO:
	278	kctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
	279	break;
	280	case LTTNG_EVENT_CONTEXT_NICE:
	281	kctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
	282	break;
	283	case LTTNG_EVENT_CONTEXT_VPID:
	284	kctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
	285	break;
	286	case LTTNG_EVENT_CONTEXT_TID:
	287	kctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
	288	break;
	289	case LTTNG_EVENT_CONTEXT_VTID:
	290	kctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
	291	break;
	292	case LTTNG_EVENT_CONTEXT_PPID:
	293	kctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
	294	break;
	295	case LTTNG_EVENT_CONTEXT_VPPID:
	296	kctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
	297	break;
	298	default:
	299	return LTTCOMM_KERN_CONTEXT_FAIL;
	300	}
	301
54d01ffb DG	302	kctx.u.perf_counter.type = ctx->u.perf_counter.type;
	303	kctx.u.perf_counter.config = ctx->u.perf_counter.config;
	304	strncpy(kctx.u.perf_counter.name, ctx->u.perf_counter.name,
	305	LTTNG_SYMBOL_NAME_LEN);
	306	kctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
b579acd9 DG	307
b579acd9 DG	308	if (strlen(channel_name) == 0) {
54d01ffb	309	ret = add_kctx_all_channels(ksession, &kctx, event_name);
b579acd9 DG	310	if (ret != LTTCOMM_OK) {
	311	goto error;
	312	}
	313	} else {
	314	/* Get kernel channel */
62499ad6	315	kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
b579acd9 DG	316	if (kchan == NULL) {
	317	ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
	318	goto error;
	319	}
	320
54d01ffb	321	ret = add_kctx_to_channel(&kctx, kchan, event_name);
b579acd9 DG	322	if (ret != LTTCOMM_OK) {
	323	goto error;
	324	}
	325	}
	326
	327	ret = LTTCOMM_OK;
	328
	329	error:
	330	return ret;
	331	}
2bdd86d4 MD	332
2bdd86d4 MD	333	/*
55cc08a6	334	* Add UST context to tracer.
2bdd86d4	335	*/
55cc08a6 DG	336	int context_ust_add(struct ltt_ust_session *usess, int domain,
	337	struct lttng_event_context ctx, char event_name,
	338	char *channel_name)
2bdd86d4	339	{
dae5ce8d	340	int ret = LTTCOMM_OK, have_event = 0;
442359c0	341	struct lttng_ht_iter iter;
bec39940	342	struct lttng_ht *chan_ht;
55cc08a6 DG	343	struct ltt_ust_channel *uchan = NULL;
55cc08a6 DG	344	struct ltt_ust_event *uevent = NULL;
2bdd86d4	345
6b79ed20 DG	346	/*
	347	* Define which channel's hashtable to use from the domain or quit if
	348	* unknown domain.
	349	*/
55cc08a6 DG	350	switch (domain) {
	351	case LTTNG_DOMAIN_UST:
	352	chan_ht = usess->domain_global.channels;
	353	break;
d78d6610	354	#if 0
55cc08a6 DG	355	case LTTNG_DOMAIN_UST_EXEC_NAME:
	356	case LTTNG_DOMAIN_UST_PID:
	357	case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
d78d6610	358	#endif
55cc08a6	359	default:
1ab1ea0b	360	ret = LTTCOMM_UND;
2bdd86d4 MD	361	goto error;
2bdd86d4 MD	362	}
2bdd86d4	363
6b79ed20	364	/* Do we have an event name */
55cc08a6 DG	365	if (strlen(event_name) != 0) {
55cc08a6 DG	366	have_event = 1;
2bdd86d4 MD	367	}
2bdd86d4 MD	368
55cc08a6 DG	369	/* Get UST channel if defined */
	370	if (strlen(channel_name) != 0) {
	371	uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
	372	if (uchan == NULL) {
	373	ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2bdd86d4 MD	374	goto error;
2bdd86d4 MD	375	}
55cc08a6 DG	376	}
	377
	378	/* If UST channel specified and event name, get UST event ref */
	379	if (uchan && have_event) {
	380	uevent = trace_ust_find_event_by_name(uchan->events, event_name);
	381	if (uevent == NULL) {
	382	ret = LTTCOMM_UST_EVENT_NOT_FOUND;
2bdd86d4	383	goto error;
2bdd86d4 MD	384	}
	385	}
	386
55cc08a6 DG	387	/* At this point, we have 4 possibilities */
55cc08a6 DG	388
6b79ed20 DG	389	if (uchan && uevent) { /* Add ctx to event in channel */
6b79ed20 DG	390	ret = add_uctx_to_event(usess, domain, uchan, uevent, ctx);
55cc08a6	391	} else if (uchan && !have_event) { /* Add ctx to channel */
6b79ed20	392	ret = add_uctx_to_channel(usess, domain, uchan, ctx);
55cc08a6	393	} else if (!uchan && have_event) { /* Add ctx to event */
6b79ed20	394	/* Add context to event without having the channel name */
bec39940	395	cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
55cc08a6 DG	396	uevent = trace_ust_find_event_by_name(uchan->events, event_name);
55cc08a6 DG	397	if (uevent != NULL) {
6b79ed20	398	ret = add_uctx_to_event(usess, domain, uchan, uevent, ctx);
55cc08a6 DG	399	/*
	400	* LTTng UST does not allowed the same event to be registered
	401	* multiple time in different or the same channel. So, if we
6b79ed20	402	* found our event, we stop.
55cc08a6 DG	403	*/
	404	goto end;
	405	}
2bdd86d4	406	}
55cc08a6	407	ret = LTTCOMM_UST_EVENT_NOT_FOUND;
6b79ed20 DG	408	goto error;
	409	} else if (!uchan && !have_event) { /* Add ctx all events, all channels */
	410	/* For all channels */
bec39940	411	cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
6b79ed20	412	ret = add_uctx_to_channel(usess, domain, uchan, ctx);
55cc08a6	413	if (ret < 0) {
ae856491	414	ERR("Context failed for channel %s", uchan->name);
55cc08a6 DG	415	continue;
55cc08a6 DG	416	}
2bdd86d4	417	}
55cc08a6	418	}
2bdd86d4	419
55cc08a6 DG	420	end:
	421	switch (ret) {
	422	case -EEXIST:
	423	ret = LTTCOMM_UST_CONTEXT_EXIST;
727d5404	424	break;
55cc08a6 DG	425	case -ENOMEM:
55cc08a6 DG	426	ret = LTTCOMM_FATAL;
727d5404 DG	427	break;
727d5404 DG	428	case -EINVAL:
ae856491	429	ret = LTTCOMM_UST_CONTEXT_INVAL;
727d5404 DG	430	break;
	431	case -ENOSYS:
	432	ret = LTTCOMM_UNKNOWN_DOMAIN;
	433	break;
	434	default:
	435	ret = LTTCOMM_OK;
	436	break;
2bdd86d4 MD	437	}
2bdd86d4 MD	438
2bdd86d4 MD	439	error:
	440	return ret;
	441	}