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

/*
 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
 *
 * 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 _LGPL_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"
#include "agent.h"

/*
 * Add kernel context to all channel.
 *
 * Assumes the ownership of kctx.
 */
static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
		struct ltt_kernel_context *kctx)
{
	int ret;
	struct ltt_kernel_channel *kchan;

	assert(ksession);
	assert(kctx);

	DBG("Adding kernel context to all channels");

	/* Go over all channels */
	cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
		struct ltt_kernel_context *kctx_copy;

		kctx_copy = trace_kernel_copy_context(kctx);
		if (!kctx_copy) {
			PERROR("zmalloc ltt_kernel_context");
			ret = -LTTNG_ERR_NOMEM;
			goto error;
		}

		/* Ownership of kctx_copy is transferred to the callee. */
		ret = kernel_add_channel_context(kchan, kctx_copy);
		kctx_copy = NULL;
		if (ret != 0) {
			goto error;
		}
	}

	ret = LTTNG_OK;

error:
	trace_kernel_destroy_context(kctx);
	return ret;
}

/*
 * Add kernel context to a specific channel.
 *
 * Assumes the ownership of kctx.
 */
static int add_kctx_to_channel(struct ltt_kernel_context *kctx,
		struct ltt_kernel_channel *kchan)
{
	int ret;

	assert(kchan);
	assert(kctx);

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

	/* Ownership of kctx is transferred to the callee. */
	ret = kernel_add_channel_context(kchan, kctx);
	kctx = NULL;
	if (ret != 0) {
		goto error;
	}

	ret = LTTNG_OK;

error:
	return ret;
}

/*
 * Add UST context to channel.
 */
static int add_uctx_to_channel(struct ltt_ust_session *usess,
		enum lttng_domain_type domain,
		struct ltt_ust_channel *uchan, struct lttng_event_context *ctx)
{
	int ret;
	struct ltt_ust_context *uctx = NULL;

	assert(usess);
	assert(uchan);
	assert(ctx);

	/* Check if context is duplicate */
	cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
		if (trace_ust_match_context(uctx, ctx)) {
			ret = LTTNG_ERR_UST_CONTEXT_EXIST;
			goto duplicate;
		}
	}
	uctx = NULL;

	switch (domain) {
	case LTTNG_DOMAIN_JUL:
	case LTTNG_DOMAIN_LOG4J:
	{
		struct agent *agt;

		if (ctx->ctx != LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
			/* Other contexts are not needed by the agent. */
			break;
		}
		agt = trace_ust_find_agent(usess, domain);

		if (!agt) {
			agt = agent_create(domain);
			if (!agt) {
				ret = -LTTNG_ERR_NOMEM;
				goto error;
			}
			agent_add(agt, usess->agents);
		}
		ret = agent_add_context(ctx, agt);
		if (ret != LTTNG_OK) {
			goto error;
		}

		ret = agent_enable_context(ctx, domain);
		if (ret != LTTNG_OK) {
			goto error;
		}
		break;
	}
	case LTTNG_DOMAIN_UST:
		break;
	default:
		assert(0);
	}

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

	ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
	if (ret < 0) {
		goto error;
	}

	rcu_read_lock();

	/* Add ltt UST context node to ltt UST channel */
	lttng_ht_add_ulong(uchan->ctx, &uctx->node);
	rcu_read_unlock();
	cds_list_add_tail(&uctx->list, &uchan->ctx_list);

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

	return 0;

error:
	free(uctx);
duplicate:
	return ret;
}

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

	assert(ksession);
	assert(ctx);
	assert(channel_name);

	kctx = trace_kernel_create_context(NULL);
	if (!kctx) {
		ret = -LTTNG_ERR_NOMEM;
		goto error;
	}

	/* Setup kernel context structure */
	switch (ctx->ctx) {
	case LTTNG_EVENT_CONTEXT_PID:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
		break;
	case LTTNG_EVENT_CONTEXT_PROCNAME:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
		break;
	case LTTNG_EVENT_CONTEXT_PRIO:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
		break;
	case LTTNG_EVENT_CONTEXT_NICE:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
		break;
	case LTTNG_EVENT_CONTEXT_VPID:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
		break;
	case LTTNG_EVENT_CONTEXT_TID:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
		break;
	case LTTNG_EVENT_CONTEXT_VTID:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
		break;
	case LTTNG_EVENT_CONTEXT_PPID:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
		break;
	case LTTNG_EVENT_CONTEXT_VPPID:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
		break;
	case LTTNG_EVENT_CONTEXT_HOSTNAME:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_HOSTNAME;
		break;
	case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
	case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER;
		break;
	case LTTNG_EVENT_CONTEXT_INTERRUPTIBLE:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE;
		break;
	case LTTNG_EVENT_CONTEXT_PREEMPTIBLE:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PREEMPTIBLE;
		break;
	case LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE;
		break;
	case LTTNG_EVENT_CONTEXT_MIGRATABLE:
		kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_MIGRATABLE;
		break;
	default:
		ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
		goto error;
	}

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

	if (*channel_name == '\0') {
		ret = add_kctx_all_channels(ksession, kctx);
		/* Ownership of kctx is transferred to the callee. */
		kctx = NULL;
		if (ret != LTTNG_OK) {
			goto error;
		}
	} else {
		/* Get kernel channel */
		kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
		if (kchan == NULL) {
			ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
			goto error;
		}

		ret = add_kctx_to_channel(kctx, kchan);
		/* Ownership of kctx is transferred to the callee. */
		kctx = NULL;
		if (ret != LTTNG_OK) {
			goto error;
		}
	}

	ret = LTTNG_OK;

error:
	if (kctx) {
		trace_kernel_destroy_context(kctx);
	}
	return ret;
}

/*
 * Add UST context to tracer.
 */
int context_ust_add(struct ltt_ust_session *usess,
		enum lttng_domain_type domain, struct lttng_event_context *ctx,
		char *channel_name)
{
	int ret = LTTNG_OK;
	struct lttng_ht_iter iter;
	struct lttng_ht *chan_ht;
	struct ltt_ust_channel *uchan = NULL;

	assert(usess);
	assert(ctx);
	assert(channel_name);

	rcu_read_lock();

	chan_ht = usess->domain_global.channels;

	/* Get UST channel if defined */
	if (channel_name[0] != '\0') {
		uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
		if (uchan == NULL) {
			ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
			goto error;
		}
	}

	if (uchan) {
		/* Add ctx to channel */
		ret = add_uctx_to_channel(usess, domain, uchan, ctx);
	} else {
		rcu_read_lock();
		/* Add ctx all events, 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) {
				ERR("Failed to add context to channel %s",
						uchan->name);
				continue;
			}
		}
		rcu_read_unlock();
	}

	switch (ret) {
	case LTTNG_ERR_UST_CONTEXT_EXIST:
		break;
	case -ENOMEM:
	case -LTTNG_ERR_NOMEM:
		ret = LTTNG_ERR_FATAL;
		break;
	case -EINVAL:
		ret = LTTNG_ERR_UST_CONTEXT_INVAL;
		break;
	case -ENOSYS:
		ret = LTTNG_ERR_UNKNOWN_DOMAIN;
		break;
	default:
		if (ret != 0 && ret != LTTNG_OK) {
			ret = ret > 0 ? ret : LTTNG_ERR_UNK;
		} else {
			ret = LTTNG_OK;
		}
		break;
	}

error:
	rcu_read_unlock();
	return ret;
}
Commit	Line	Data
b579acd9	1	/*
bdf64013 JG	2	* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
bdf64013 JG	3	* Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
b579acd9	4	*
d14d33bf AM	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License, version 2 only,
	7	* as published by the Free Software Foundation.
b579acd9	8	*
d14d33bf AM	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
b579acd9	13	*
d14d33bf AM	14	* You should have received a copy of the GNU General Public License along
	15	* with this program; if not, write to the Free Software Foundation, Inc.,
	16	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
b579acd9 DG	17	*/
b579acd9 DG	18
6c1c0768	19	#define _LGPL_SOURCE
b579acd9 DG	20	#include <stdio.h>
	21	#include <stdlib.h>
	22	#include <string.h>
	23	#include <unistd.h>
54d01ffb	24	#include <urcu/list.h>
1e307fab	25
db758600	26	#include <common/error.h>
10a8a223	27	#include <common/sessiond-comm/sessiond-comm.h>
b579acd9	28
b579acd9	29	#include "context.h"
4771f025	30	#include "kernel.h"
55cc08a6	31	#include "ust-app.h"
34378f76	32	#include "trace-ust.h"
bdf64013	33	#include "agent.h"
b579acd9	34
b579acd9 DG	35	/*
b579acd9 DG	36	* Add kernel context to all channel.
df3c77c8 JG	37	*
df3c77c8 JG	38	* Assumes the ownership of kctx.
b579acd9 DG	39	*/
b579acd9 DG	40	static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
645328ae	41	struct ltt_kernel_context *kctx)
b579acd9	42	{
601d5acf	43	int ret;
b579acd9 DG	44	struct ltt_kernel_channel *kchan;
b579acd9 DG	45
0525e9ae DG	46	assert(ksession);
	47	assert(kctx);
	48
601d5acf	49	DBG("Adding kernel context to all channels");
b579acd9 DG	50
	51	/* Go over all channels */
	52	cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
df3c77c8 JG	53	struct ltt_kernel_context *kctx_copy;
	54
	55	kctx_copy = trace_kernel_copy_context(kctx);
	56	if (!kctx_copy) {
	57	PERROR("zmalloc ltt_kernel_context");
7682f304	58	ret = -LTTNG_ERR_NOMEM;
df3c77c8 JG	59	goto error;
	60	}
	61
	62	/* Ownership of kctx_copy is transferred to the callee. */
	63	ret = kernel_add_channel_context(kchan, kctx_copy);
	64	kctx_copy = NULL;
1ae5e83e	65	if (ret != 0) {
601d5acf	66	goto error;
b579acd9 DG	67	}
	68	}
	69
f73fabfd	70	ret = LTTNG_OK;
b579acd9 DG	71
b579acd9 DG	72	error:
df3c77c8	73	trace_kernel_destroy_context(kctx);
b579acd9 DG	74	return ret;
	75	}
	76
	77	/*
	78	* Add kernel context to a specific channel.
df3c77c8 JG	79	*
df3c77c8 JG	80	* Assumes the ownership of kctx.
b579acd9	81	*/
645328ae	82	static int add_kctx_to_channel(struct ltt_kernel_context *kctx,
601d5acf	83	struct ltt_kernel_channel *kchan)
b579acd9	84	{
601d5acf	85	int ret;
b579acd9	86
0525e9ae DG	87	assert(kchan);
	88	assert(kctx);
	89
601d5acf	90	DBG("Add kernel context to channel '%s'", kchan->channel->name);
b579acd9	91
df3c77c8	92	/* Ownership of kctx is transferred to the callee. */
601d5acf	93	ret = kernel_add_channel_context(kchan, kctx);
df3c77c8	94	kctx = NULL;
1ae5e83e	95	if (ret != 0) {
b579acd9 DG	96	goto error;
	97	}
	98
f73fabfd	99	ret = LTTNG_OK;
b579acd9 DG	100
	101	error:
	102	return ret;
	103	}
	104
6b79ed20 DG	105	/*
	106	* Add UST context to channel.
	107	*/
4ce7709b JG	108	static int add_uctx_to_channel(struct ltt_ust_session *usess,
4ce7709b JG	109	enum lttng_domain_type domain,
6b79ed20 DG	110	struct ltt_ust_channel uchan, struct lttng_event_context ctx)
	111	{
	112	int ret;
bdf64013	113	struct ltt_ust_context *uctx = NULL;
6b79ed20	114
0525e9ae DG	115	assert(usess);
	116	assert(uchan);
	117	assert(ctx);
	118
aa3514e9 MD	119	/* Check if context is duplicate */
	120	cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
	121	if (trace_ust_match_context(uctx, ctx)) {
7682f304	122	ret = LTTNG_ERR_UST_CONTEXT_EXIST;
aa3514e9 MD	123	goto duplicate;
	124	}
	125	}
bdf64013 JG	126	uctx = NULL;
	127
	128	switch (domain) {
	129	case LTTNG_DOMAIN_JUL:
	130	case LTTNG_DOMAIN_LOG4J:
	131	{
442f8c07 JG	132	struct agent *agt;
	133
	134	if (ctx->ctx != LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
	135	/* Other contexts are not needed by the agent. */
	136	break;
	137	}
	138	agt = trace_ust_find_agent(usess, domain);
bdf64013 JG	139
	140	if (!agt) {
	141	agt = agent_create(domain);
	142	if (!agt) {
7682f304	143	ret = -LTTNG_ERR_NOMEM;
bdf64013 JG	144	goto error;
	145	}
	146	agent_add(agt, usess->agents);
	147	}
	148	ret = agent_add_context(ctx, agt);
	149	if (ret != LTTNG_OK) {
	150	goto error;
	151	}
	152
	153	ret = agent_enable_context(ctx, domain);
	154	if (ret != LTTNG_OK) {
	155	goto error;
	156	}
	157	break;
	158	}
	159	case LTTNG_DOMAIN_UST:
	160	break;
	161	default:
	162	assert(0);
	163	}
aa3514e9	164
6b79ed20 DG	165	/* Create ltt UST context */
	166	uctx = trace_ust_create_context(ctx);
	167	if (uctx == NULL) {
7682f304	168	ret = LTTNG_ERR_UST_CONTEXT_INVAL;
6b79ed20 DG	169	goto error;
	170	}
	171
c0c66aec JG	172	ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
c0c66aec JG	173	if (ret < 0) {
727d5404 DG	174	goto error;
	175	}
	176
e7fe706f DG	177	rcu_read_lock();
e7fe706f DG	178
6b79ed20	179	/* Add ltt UST context node to ltt UST channel */
aa3514e9	180	lttng_ht_add_ulong(uchan->ctx, &uctx->node);
e7fe706f	181	rcu_read_unlock();
31746f93	182	cds_list_add_tail(&uctx->list, &uchan->ctx_list);
6b79ed20	183
727d5404 DG	184	DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
	185
	186	return 0;
6b79ed20 DG	187
	188	error:
	189	free(uctx);
aa3514e9	190	duplicate:
6b79ed20 DG	191	return ret;
	192	}
	193
b579acd9 DG	194	/*
	195	* Add kernel context to tracer.
	196	*/
54d01ffb	197	int context_kernel_add(struct ltt_kernel_session *ksession,
601d5acf	198	struct lttng_event_context ctx, char channel_name)
b579acd9 DG	199	{
	200	int ret;
	201	struct ltt_kernel_channel *kchan;
645328ae	202	struct ltt_kernel_context *kctx;
54d01ffb	203
0525e9ae DG	204	assert(ksession);
	205	assert(ctx);
	206	assert(channel_name);
	207
645328ae DG	208	kctx = trace_kernel_create_context(NULL);
645328ae DG	209	if (!kctx) {
7682f304	210	ret = -LTTNG_ERR_NOMEM;
645328ae DG	211	goto error;
	212	}
	213
54d01ffb	214	/* Setup kernel context structure */
9197c5c4 MD	215	switch (ctx->ctx) {
9197c5c4 MD	216	case LTTNG_EVENT_CONTEXT_PID:
645328ae	217	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PID;
9197c5c4	218	break;
9197c5c4	219	case LTTNG_EVENT_CONTEXT_PROCNAME:
645328ae	220	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PROCNAME;
9197c5c4 MD	221	break;
9197c5c4 MD	222	case LTTNG_EVENT_CONTEXT_PRIO:
645328ae	223	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PRIO;
9197c5c4 MD	224	break;
9197c5c4 MD	225	case LTTNG_EVENT_CONTEXT_NICE:
645328ae	226	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NICE;
9197c5c4 MD	227	break;
9197c5c4 MD	228	case LTTNG_EVENT_CONTEXT_VPID:
645328ae	229	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPID;
9197c5c4 MD	230	break;
9197c5c4 MD	231	case LTTNG_EVENT_CONTEXT_TID:
645328ae	232	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_TID;
9197c5c4 MD	233	break;
9197c5c4 MD	234	case LTTNG_EVENT_CONTEXT_VTID:
645328ae	235	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VTID;
9197c5c4 MD	236	break;
9197c5c4 MD	237	case LTTNG_EVENT_CONTEXT_PPID:
645328ae	238	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PPID;
9197c5c4 MD	239	break;
9197c5c4 MD	240	case LTTNG_EVENT_CONTEXT_VPPID:
645328ae	241	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_VPPID;
9197c5c4	242	break;
54773d68	243	case LTTNG_EVENT_CONTEXT_HOSTNAME:
645328ae	244	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_HOSTNAME;
54773d68	245	break;
aa3514e9 MD	246	case LTTNG_EVENT_CONTEXT_PERF_CPU_COUNTER:
aa3514e9 MD	247	case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
645328ae	248	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER;
aa3514e9	249	break;
1ae5e83e JD	250	case LTTNG_EVENT_CONTEXT_INTERRUPTIBLE:
	251	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE;
	252	break;
	253	case LTTNG_EVENT_CONTEXT_PREEMPTIBLE:
	254	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PREEMPTIBLE;
	255	break;
	256	case LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE:
	257	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE;
	258	break;
	259	case LTTNG_EVENT_CONTEXT_MIGRATABLE:
	260	kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_MIGRATABLE;
	261	break;
9197c5c4	262	default:
fc7324e8 DG	263	ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
fc7324e8 DG	264	goto error;
9197c5c4 MD	265	}
9197c5c4 MD	266
645328ae DG	267	kctx->ctx.u.perf_counter.type = ctx->u.perf_counter.type;
	268	kctx->ctx.u.perf_counter.config = ctx->u.perf_counter.config;
	269	strncpy(kctx->ctx.u.perf_counter.name, ctx->u.perf_counter.name,
54d01ffb	270	LTTNG_SYMBOL_NAME_LEN);
645328ae	271	kctx->ctx.u.perf_counter.name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
b579acd9	272
9d035200	273	if (*channel_name == '\0') {
645328ae	274	ret = add_kctx_all_channels(ksession, kctx);
df3c77c8 JG	275	/* Ownership of kctx is transferred to the callee. */
df3c77c8 JG	276	kctx = NULL;
f73fabfd	277	if (ret != LTTNG_OK) {
b579acd9 DG	278	goto error;
	279	}
	280	} else {
	281	/* Get kernel channel */
62499ad6	282	kchan = trace_kernel_get_channel_by_name(channel_name, ksession);
b579acd9	283	if (kchan == NULL) {
f73fabfd	284	ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
b579acd9 DG	285	goto error;
	286	}
	287
645328ae	288	ret = add_kctx_to_channel(kctx, kchan);
df3c77c8 JG	289	/* Ownership of kctx is transferred to the callee. */
df3c77c8 JG	290	kctx = NULL;
f73fabfd	291	if (ret != LTTNG_OK) {
b579acd9 DG	292	goto error;
	293	}
	294	}
	295
df3c77c8	296	ret = LTTNG_OK;
b579acd9 DG	297
b579acd9 DG	298	error:
fc7324e8 DG	299	if (kctx) {
	300	trace_kernel_destroy_context(kctx);
	301	}
b579acd9 DG	302	return ret;
b579acd9 DG	303	}
2bdd86d4 MD	304
2bdd86d4 MD	305	/*
55cc08a6	306	* Add UST context to tracer.
2bdd86d4	307	*/
4ce7709b JG	308	int context_ust_add(struct ltt_ust_session *usess,
	309	enum lttng_domain_type domain, struct lttng_event_context *ctx,
	310	char *channel_name)
2bdd86d4	311	{
601d5acf	312	int ret = LTTNG_OK;
442359c0	313	struct lttng_ht_iter iter;
bec39940	314	struct lttng_ht *chan_ht;
55cc08a6	315	struct ltt_ust_channel *uchan = NULL;
2bdd86d4	316
0525e9ae DG	317	assert(usess);
	318	assert(ctx);
	319	assert(channel_name);
	320
2223c96f DG	321	rcu_read_lock();
2223c96f DG	322
f5501dad	323	chan_ht = usess->domain_global.channels;
2bdd86d4	324
55cc08a6	325	/* Get UST channel if defined */
9f9ee9c9	326	if (channel_name[0] != '\0') {
55cc08a6 DG	327	uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
55cc08a6 DG	328	if (uchan == NULL) {
f73fabfd	329	ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2bdd86d4 MD	330	goto error;
2bdd86d4 MD	331	}
55cc08a6 DG	332	}
55cc08a6 DG	333
601d5acf DG	334	if (uchan) {
601d5acf DG	335	/* Add ctx to channel */
6b79ed20	336	ret = add_uctx_to_channel(usess, domain, uchan, ctx);
601d5acf	337	} else {
e7fe706f	338	rcu_read_lock();
601d5acf	339	/* Add ctx all events, all channels */
bec39940	340	cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
6b79ed20	341	ret = add_uctx_to_channel(usess, domain, uchan, ctx);
7682f304	342	if (ret) {
9589be74 JG	343	ERR("Failed to add context to channel %s",
9589be74 JG	344	uchan->name);
55cc08a6 DG	345	continue;
55cc08a6 DG	346	}
2bdd86d4	347	}
e7fe706f	348	rcu_read_unlock();
55cc08a6	349	}
2bdd86d4	350
55cc08a6	351	switch (ret) {
7682f304	352	case LTTNG_ERR_UST_CONTEXT_EXIST:
727d5404	353	break;
55cc08a6	354	case -ENOMEM:
7682f304	355	case -LTTNG_ERR_NOMEM:
f73fabfd	356	ret = LTTNG_ERR_FATAL;
727d5404 DG	357	break;
727d5404 DG	358	case -EINVAL:
f73fabfd	359	ret = LTTNG_ERR_UST_CONTEXT_INVAL;
727d5404 DG	360	break;
727d5404 DG	361	case -ENOSYS:
f73fabfd	362	ret = LTTNG_ERR_UNKNOWN_DOMAIN;
727d5404 DG	363	break;
727d5404 DG	364	default:
7682f304 JG	365	if (ret != 0 && ret != LTTNG_OK) {
	366	ret = ret > 0 ? ret : LTTNG_ERR_UNK;
	367	} else {
	368	ret = LTTNG_OK;
	369	}
727d5404	370	break;
2bdd86d4 MD	371	}
2bdd86d4 MD	372
2bdd86d4	373	error:
2223c96f	374	rcu_read_unlock();
2bdd86d4 MD	375	return ret;
2bdd86d4 MD	376	}