[lttng-tools.git] / src / bin / lttng-sessiond / tracker.cpp

/*
 * Copyright (C) 2018 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 * Copyright (C) 2020 Jérémie Galarneau <jeremie.galarneau@efficios.com>
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 */

#include "common/dynamic-array.hpp"
#include "common/macros.hpp"
#include "lttng/tracker.h"
#define _LGPL_SOURCE
#include "tracker.hpp"

#include <common/defaults.hpp>
#include <common/error.hpp>
#include <common/hashtable/hashtable.hpp>
#include <common/hashtable/utils.hpp>
#include <common/tracker.hpp>
#include <common/urcu.hpp>

#include <lttng/lttng-error.h>

#include <grp.h>
#include <pwd.h>
#include <sys/types.h>
#include <unistd.h>
#include <urcu.h>
#include <urcu/list.h>
#include <urcu/rculfhash.h>

struct process_attr_tracker {
	enum lttng_tracking_policy policy;
	struct cds_lfht *inclusion_set_ht;
};

namespace {
struct process_attr_tracker_value_node {
	struct process_attr_value *value;
	struct cds_lfht_node inclusion_set_ht_node;
	struct rcu_head rcu_head;
};
} /* namespace */

static void process_attr_tracker_value_node_rcu_free(struct rcu_head *rcu_head)
{
	struct process_attr_tracker_value_node *node =
		lttng::utils::container_of(rcu_head, &process_attr_tracker_value_node::rcu_head);

	free(node);
}

struct process_attr_tracker *process_attr_tracker_create()
{
	struct process_attr_tracker *tracker;

	tracker = zmalloc<process_attr_tracker>();
	if (!tracker) {
		return nullptr;
	}

	(void) process_attr_tracker_set_tracking_policy(tracker, LTTNG_TRACKING_POLICY_INCLUDE_ALL);

	tracker->inclusion_set_ht = cds_lfht_new(
		DEFAULT_HT_SIZE, 1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, nullptr);
	if (!tracker->inclusion_set_ht) {
		goto error;
	}

	return tracker;
error:
	process_attr_tracker_destroy(tracker);
	return nullptr;
}

static void
process_attr_tracker_remove_value_node(struct process_attr_tracker *tracker,
				       struct process_attr_tracker_value_node *value_node)
{
	cds_lfht_del(tracker->inclusion_set_ht, &value_node->inclusion_set_ht_node);
	process_attr_value_destroy(value_node->value);
	call_rcu(&value_node->rcu_head, process_attr_tracker_value_node_rcu_free);
}

static void process_attr_tracker_clear_inclusion_set(struct process_attr_tracker *tracker)
{
	if (!tracker->inclusion_set_ht) {
		return;
	}

	for (auto *value_node : lttng::urcu::lfht_iteration_adapter<
		     process_attr_tracker_value_node,
		     decltype(process_attr_tracker_value_node::inclusion_set_ht_node),
		     &process_attr_tracker_value_node::inclusion_set_ht_node>(
		     *tracker->inclusion_set_ht)) {
		process_attr_tracker_remove_value_node(tracker, value_node);
	}

	const auto ret = cds_lfht_destroy(tracker->inclusion_set_ht, nullptr);
	LTTNG_ASSERT(ret == 0);
	tracker->inclusion_set_ht = nullptr;
}

static int process_attr_tracker_create_inclusion_set(struct process_attr_tracker *tracker)
{
	LTTNG_ASSERT(!tracker->inclusion_set_ht);
	tracker->inclusion_set_ht = cds_lfht_new(
		DEFAULT_HT_SIZE, 1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, nullptr);
	return tracker->inclusion_set_ht ? 0 : -1;
}

void process_attr_tracker_destroy(struct process_attr_tracker *tracker)
{
	if (!tracker) {
		return;
	}

	process_attr_tracker_clear_inclusion_set(tracker);
	free(tracker);
}

enum lttng_tracking_policy
process_attr_tracker_get_tracking_policy(const struct process_attr_tracker *tracker)
{
	return tracker->policy;
}

int process_attr_tracker_set_tracking_policy(struct process_attr_tracker *tracker,
					     enum lttng_tracking_policy tracking_policy)
{
	int ret = 0;

	if (tracker->policy == tracking_policy) {
		goto end;
	}

	process_attr_tracker_clear_inclusion_set(tracker);
	ret = process_attr_tracker_create_inclusion_set(tracker);
	if (ret) {
		goto end;
	}
	tracker->policy = tracking_policy;
end:
	return ret;
}

static int match_inclusion_set_value(struct cds_lfht_node *node, const void *key)
{
	const struct process_attr_value *value_key = (process_attr_value *) key;
	const struct process_attr_tracker_value_node *value_node = caa_container_of(
		node, struct process_attr_tracker_value_node, inclusion_set_ht_node);

	return process_attr_tracker_value_equal(value_node->value, value_key);
}

static struct process_attr_tracker_value_node *
process_attr_tracker_lookup(const struct process_attr_tracker *tracker,
			    const struct process_attr_value *value)
{
	struct cds_lfht_iter iter;
	struct cds_lfht_node *node;

	LTTNG_ASSERT(tracker->policy == LTTNG_TRACKING_POLICY_INCLUDE_SET);

	const lttng::urcu::read_lock_guard read_lock;
	cds_lfht_lookup(tracker->inclusion_set_ht,
			process_attr_value_hash(value),
			match_inclusion_set_value,
			value,
			&iter);
	node = cds_lfht_iter_get_node(&iter);

	return node ? lttng::utils::container_of(
			      node, &process_attr_tracker_value_node::inclusion_set_ht_node) :
		      nullptr;
}

/* Protected by session mutex held by caller. */
enum process_attr_tracker_status
process_attr_tracker_inclusion_set_add_value(struct process_attr_tracker *tracker,
					     const struct process_attr_value *value)
{
	enum process_attr_tracker_status status = PROCESS_ATTR_TRACKER_STATUS_OK;
	struct process_attr_value *value_copy = nullptr;
	struct process_attr_tracker_value_node *value_node = nullptr;

	const lttng::urcu::read_lock_guard read_lock;
	if (tracker->policy != LTTNG_TRACKING_POLICY_INCLUDE_SET) {
		status = PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY;
		goto end;
	}

	if (process_attr_tracker_lookup(tracker, value)) {
		status = PROCESS_ATTR_TRACKER_STATUS_EXISTS;
		goto end;
	}

	value_node = zmalloc<process_attr_tracker_value_node>();
	if (!value_node) {
		status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
		goto end;
	}

	value_copy = process_attr_value_copy(value);
	if (!value_copy) {
		status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
		goto end;
	}

	value_node->value = value_copy;
	cds_lfht_add(tracker->inclusion_set_ht,
		     process_attr_value_hash(value_copy),
		     &value_node->inclusion_set_ht_node);
	value_copy = nullptr;
	value_node = nullptr;
end:
	if (value_copy) {
		process_attr_value_destroy(value_copy);
	}
	if (value_node) {
		free(value_node);
	}
	return status;
}

/* Protected by session mutex held by caller. */
enum process_attr_tracker_status
process_attr_tracker_inclusion_set_remove_value(struct process_attr_tracker *tracker,
						const struct process_attr_value *value)
{
	struct process_attr_tracker_value_node *value_node;
	enum process_attr_tracker_status status = PROCESS_ATTR_TRACKER_STATUS_OK;

	const lttng::urcu::read_lock_guard read_lock;
	if (tracker->policy != LTTNG_TRACKING_POLICY_INCLUDE_SET) {
		status = PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY;
		goto end;
	}

	value_node = process_attr_tracker_lookup(tracker, value);
	if (!value_node) {
		status = PROCESS_ATTR_TRACKER_STATUS_MISSING;
		goto end;
	}

	process_attr_tracker_remove_value_node(tracker, value_node);
end:
	return status;
}

enum process_attr_tracker_status
process_attr_tracker_get_inclusion_set(const struct process_attr_tracker *tracker,
				       struct lttng_process_attr_values **_values)
{
	enum process_attr_tracker_status status = PROCESS_ATTR_TRACKER_STATUS_OK;
	struct lttng_process_attr_values *values;
	struct process_attr_value *new_value = nullptr;

	values = lttng_process_attr_values_create();
	if (!values) {
		status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
		goto error;
	}

	if (tracker->policy != LTTNG_TRACKING_POLICY_INCLUDE_SET) {
		status = PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY;
		goto error;
	}

	for (auto *value_node : lttng::urcu::lfht_iteration_adapter<
		     process_attr_tracker_value_node,
		     decltype(process_attr_tracker_value_node::inclusion_set_ht_node),
		     &process_attr_tracker_value_node::inclusion_set_ht_node>(
		     *tracker->inclusion_set_ht)) {
		int ret;

		new_value = process_attr_value_copy(value_node->value);
		if (!new_value) {
			status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
			goto error_unlock;
		}

		ret = lttng_dynamic_pointer_array_add_pointer(&values->array, new_value);
		if (ret) {
			status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
			goto error_unlock;
		}

		new_value = nullptr;
	}

	*_values = values;
	return status;
error_unlock:
error:
	lttng_process_attr_values_destroy(values);
	process_attr_value_destroy(new_value);
	return status;
}
Commit	Line	Data
	1	/*
	2	* Copyright (C) 2018 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	3	* Copyright (C) 2020 Jérémie Galarneau <jeremie.galarneau@efficios.com>
	4	*
	5	* SPDX-License-Identifier: GPL-2.0-only
	6	*
	7	*/
	8
	9	#include "common/dynamic-array.hpp"
	10	#include "common/macros.hpp"
	11	#include "lttng/tracker.h"
	12	#define _LGPL_SOURCE
	13	#include "tracker.hpp"
	14
	15	#include <common/defaults.hpp>
	16	#include <common/error.hpp>
	17	#include <common/hashtable/hashtable.hpp>
	18	#include <common/hashtable/utils.hpp>
	19	#include <common/tracker.hpp>
	20	#include <common/urcu.hpp>
	21
	22	#include <lttng/lttng-error.h>
	23
	24	#include <grp.h>
	25	#include <pwd.h>
	26	#include <sys/types.h>
	27	#include <unistd.h>
	28	#include <urcu.h>
	29	#include <urcu/list.h>
	30	#include <urcu/rculfhash.h>
	31
	32	struct process_attr_tracker {
	33	enum lttng_tracking_policy policy;
	34	struct cds_lfht *inclusion_set_ht;
	35	};
	36
	37	namespace {
	38	struct process_attr_tracker_value_node {
	39	struct process_attr_value *value;
	40	struct cds_lfht_node inclusion_set_ht_node;
	41	struct rcu_head rcu_head;
	42	};
	43	} /* namespace */
	44
	45	static void process_attr_tracker_value_node_rcu_free(struct rcu_head *rcu_head)
	46	{
	47	struct process_attr_tracker_value_node *node =
	48	lttng::utils::container_of(rcu_head, &process_attr_tracker_value_node::rcu_head);
	49
	50	free(node);
	51	}
	52
	53	struct process_attr_tracker *process_attr_tracker_create()
	54	{
	55	struct process_attr_tracker *tracker;
	56
	57	tracker = zmalloc<process_attr_tracker>();
	58	if (!tracker) {
	59	return nullptr;
	60	}
	61
	62	(void) process_attr_tracker_set_tracking_policy(tracker, LTTNG_TRACKING_POLICY_INCLUDE_ALL);
	63
	64	tracker->inclusion_set_ht = cds_lfht_new(
	65	DEFAULT_HT_SIZE, 1, 0, CDS_LFHT_AUTO_RESIZE \| CDS_LFHT_ACCOUNTING, nullptr);
	66	if (!tracker->inclusion_set_ht) {
	67	goto error;
	68	}
	69
	70	return tracker;
	71	error:
	72	process_attr_tracker_destroy(tracker);
	73	return nullptr;
	74	}
	75
	76	static void
	77	process_attr_tracker_remove_value_node(struct process_attr_tracker *tracker,
	78	struct process_attr_tracker_value_node *value_node)
	79	{
	80	cds_lfht_del(tracker->inclusion_set_ht, &value_node->inclusion_set_ht_node);
	81	process_attr_value_destroy(value_node->value);
	82	call_rcu(&value_node->rcu_head, process_attr_tracker_value_node_rcu_free);
	83	}
	84
	85	static void process_attr_tracker_clear_inclusion_set(struct process_attr_tracker *tracker)
	86	{
	87	if (!tracker->inclusion_set_ht) {
	88	return;
	89	}
	90
	91	for (auto *value_node : lttng::urcu::lfht_iteration_adapter<
	92	process_attr_tracker_value_node,
	93	decltype(process_attr_tracker_value_node::inclusion_set_ht_node),
	94	&process_attr_tracker_value_node::inclusion_set_ht_node>(
	95	*tracker->inclusion_set_ht)) {
	96	process_attr_tracker_remove_value_node(tracker, value_node);
	97	}
	98
	99	const auto ret = cds_lfht_destroy(tracker->inclusion_set_ht, nullptr);
	100	LTTNG_ASSERT(ret == 0);
	101	tracker->inclusion_set_ht = nullptr;
	102	}
	103
	104	static int process_attr_tracker_create_inclusion_set(struct process_attr_tracker *tracker)
	105	{
	106	LTTNG_ASSERT(!tracker->inclusion_set_ht);
	107	tracker->inclusion_set_ht = cds_lfht_new(
	108	DEFAULT_HT_SIZE, 1, 0, CDS_LFHT_AUTO_RESIZE \| CDS_LFHT_ACCOUNTING, nullptr);
	109	return tracker->inclusion_set_ht ? 0 : -1;
	110	}
	111
	112	void process_attr_tracker_destroy(struct process_attr_tracker *tracker)
	113	{
	114	if (!tracker) {
	115	return;
	116	}
	117
	118	process_attr_tracker_clear_inclusion_set(tracker);
	119	free(tracker);
	120	}
	121
	122	enum lttng_tracking_policy
	123	process_attr_tracker_get_tracking_policy(const struct process_attr_tracker *tracker)
	124	{
	125	return tracker->policy;
	126	}
	127
	128	int process_attr_tracker_set_tracking_policy(struct process_attr_tracker *tracker,
	129	enum lttng_tracking_policy tracking_policy)
	130	{
	131	int ret = 0;
	132
	133	if (tracker->policy == tracking_policy) {
	134	goto end;
	135	}
	136
	137	process_attr_tracker_clear_inclusion_set(tracker);
	138	ret = process_attr_tracker_create_inclusion_set(tracker);
	139	if (ret) {
	140	goto end;
	141	}
	142	tracker->policy = tracking_policy;
	143	end:
	144	return ret;
	145	}
	146
	147	static int match_inclusion_set_value(struct cds_lfht_node node, const void key)
	148	{
	149	const struct process_attr_value value_key = (process_attr_value ) key;
	150	const struct process_attr_tracker_value_node *value_node = caa_container_of(
	151	node, struct process_attr_tracker_value_node, inclusion_set_ht_node);
	152
	153	return process_attr_tracker_value_equal(value_node->value, value_key);
	154	}
	155
	156	static struct process_attr_tracker_value_node *
	157	process_attr_tracker_lookup(const struct process_attr_tracker *tracker,
	158	const struct process_attr_value *value)
	159	{
	160	struct cds_lfht_iter iter;
	161	struct cds_lfht_node *node;
	162
	163	LTTNG_ASSERT(tracker->policy == LTTNG_TRACKING_POLICY_INCLUDE_SET);
	164
	165	const lttng::urcu::read_lock_guard read_lock;
	166	cds_lfht_lookup(tracker->inclusion_set_ht,
	167	process_attr_value_hash(value),
	168	match_inclusion_set_value,
	169	value,
	170	&iter);
	171	node = cds_lfht_iter_get_node(&iter);
	172
	173	return node ? lttng::utils::container_of(
	174	node, &process_attr_tracker_value_node::inclusion_set_ht_node) :
	175	nullptr;
	176	}
	177
	178	/* Protected by session mutex held by caller. */
	179	enum process_attr_tracker_status
	180	process_attr_tracker_inclusion_set_add_value(struct process_attr_tracker *tracker,
	181	const struct process_attr_value *value)
	182	{
	183	enum process_attr_tracker_status status = PROCESS_ATTR_TRACKER_STATUS_OK;
	184	struct process_attr_value *value_copy = nullptr;
	185	struct process_attr_tracker_value_node *value_node = nullptr;
	186
	187	const lttng::urcu::read_lock_guard read_lock;
	188	if (tracker->policy != LTTNG_TRACKING_POLICY_INCLUDE_SET) {
	189	status = PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY;
	190	goto end;
	191	}
	192
	193	if (process_attr_tracker_lookup(tracker, value)) {
	194	status = PROCESS_ATTR_TRACKER_STATUS_EXISTS;
	195	goto end;
	196	}
	197
	198	value_node = zmalloc<process_attr_tracker_value_node>();
	199	if (!value_node) {
	200	status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
	201	goto end;
	202	}
	203
	204	value_copy = process_attr_value_copy(value);
	205	if (!value_copy) {
	206	status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
	207	goto end;
	208	}
	209
	210	value_node->value = value_copy;
	211	cds_lfht_add(tracker->inclusion_set_ht,
	212	process_attr_value_hash(value_copy),
	213	&value_node->inclusion_set_ht_node);
	214	value_copy = nullptr;
	215	value_node = nullptr;
	216	end:
	217	if (value_copy) {
	218	process_attr_value_destroy(value_copy);
	219	}
	220	if (value_node) {
	221	free(value_node);
	222	}
	223	return status;
	224	}
	225
	226	/* Protected by session mutex held by caller. */
	227	enum process_attr_tracker_status
	228	process_attr_tracker_inclusion_set_remove_value(struct process_attr_tracker *tracker,
	229	const struct process_attr_value *value)
	230	{
	231	struct process_attr_tracker_value_node *value_node;
	232	enum process_attr_tracker_status status = PROCESS_ATTR_TRACKER_STATUS_OK;
	233
	234	const lttng::urcu::read_lock_guard read_lock;
	235	if (tracker->policy != LTTNG_TRACKING_POLICY_INCLUDE_SET) {
	236	status = PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY;
	237	goto end;
	238	}
	239
	240	value_node = process_attr_tracker_lookup(tracker, value);
	241	if (!value_node) {
	242	status = PROCESS_ATTR_TRACKER_STATUS_MISSING;
	243	goto end;
	244	}
	245
	246	process_attr_tracker_remove_value_node(tracker, value_node);
	247	end:
	248	return status;
	249	}
	250
	251	enum process_attr_tracker_status
	252	process_attr_tracker_get_inclusion_set(const struct process_attr_tracker *tracker,
	253	struct lttng_process_attr_values **_values)
	254	{
	255	enum process_attr_tracker_status status = PROCESS_ATTR_TRACKER_STATUS_OK;
	256	struct lttng_process_attr_values *values;
	257	struct process_attr_value *new_value = nullptr;
	258
	259	values = lttng_process_attr_values_create();
	260	if (!values) {
	261	status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
	262	goto error;
	263	}
	264
	265	if (tracker->policy != LTTNG_TRACKING_POLICY_INCLUDE_SET) {
	266	status = PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY;
	267	goto error;
	268	}
	269
	270	for (auto *value_node : lttng::urcu::lfht_iteration_adapter<
	271	process_attr_tracker_value_node,
	272	decltype(process_attr_tracker_value_node::inclusion_set_ht_node),
	273	&process_attr_tracker_value_node::inclusion_set_ht_node>(
	274	*tracker->inclusion_set_ht)) {
	275	int ret;
	276
	277	new_value = process_attr_value_copy(value_node->value);
	278	if (!new_value) {
	279	status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
	280	goto error_unlock;
	281	}
	282
	283	ret = lttng_dynamic_pointer_array_add_pointer(&values->array, new_value);
	284	if (ret) {
	285	status = PROCESS_ATTR_TRACKER_STATUS_ERROR;
	286	goto error_unlock;
	287	}
	288
	289	new_value = nullptr;
	290	}
	291
	292	*_values = values;
	293	return status;
	294	error_unlock:
	295	error:
	296	lttng_process_attr_values_destroy(values);
	297	process_attr_value_destroy(new_value);
	298	return status;
	299	}