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

/*
 * Copyright (C) 2011 David Goulet <dgoulet@efficios.com>
 * Copyright (C) 2014 Jan Glauber <jan.glauber@gmail.com>
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 */

/**
 * @file modprobe.c
 *
 * @brief modprobe related functions.
 *
 */

#define _LGPL_SOURCE
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>

#include <common/common.h>
#include <common/utils.h>

#include "modprobe.h"
#include "kern-modules.h"
#include "lttng-sessiond.h"

/* LTTng kernel tracer mandatory core modules list */
struct kern_modules_param kern_modules_control_core[] = {
	{
		.name = (char *) "lttng-ring-buffer-client-discard",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	},
	{
		.name = (char *) "lttng-ring-buffer-client-overwrite",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	},
	{
		.name = (char *) "lttng-ring-buffer-metadata-client",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	},
	{
		.name = (char *) "lttng-ring-buffer-client-mmap-discard",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	},
	{
		.name = (char *) "lttng-ring-buffer-client-mmap-overwrite",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	},
	{
		.name = (char *) "lttng-ring-buffer-metadata-mmap-client",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	},
	{
		.name = (char *) "lttng-ring-buffer-event_notifier-client",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
};

/* LTTng kerneltracer probe modules list */
struct kern_modules_param kern_modules_probes_default[] = {
	{
		.name = (char *) "lttng-probe-asoc",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-block",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-btrfs",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-compaction",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-ext3",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-ext4",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-gpio",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-i2c",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-irq",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-jbd",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-jbd2",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-kmem",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-kvm",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-kvm-x86",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-kvm-x86-mmu",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-lock",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-module",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-napi",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-net",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-power",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-preemptirq",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-printk",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-random",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-rcu",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-regmap",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-regulator",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-rpm",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-sched",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-scsi",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-signal",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-skb",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-sock",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-statedump",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-sunrpc",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-timer",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-udp",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-vmscan",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-v4l2",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-workqueue",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-writeback",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-x86-irq-vectors",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
	{
		.name = (char *) "lttng-probe-x86-exceptions",
		.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	},
};

/* dynamic probe modules list */
static struct kern_modules_param *probes;
static int nr_probes;
static int probes_capacity;

#if HAVE_KMOD
#include <libkmod.h>

/**
 * @brief Logging function for libkmod integration.
 */
static void log_kmod(void *data, int priority, const char *file, int line,
		const char *fn, const char *format, va_list args)
{
	char *str;

	if (vasprintf(&str, format, args) < 0) {
		return;
	}

	DBG("libkmod: %s", str);
	free(str);
}

/**
 * @brief Setup the libkmod context.
 *
 * Create the context, add a custom logging function and preload the
 * ressources for faster operation.
 *
 * @returns	\c 0 on success
 * 		\c < 0 on error
 */
static int setup_kmod_ctx(struct kmod_ctx **ctx)
{
	int ret = 0;

	*ctx = kmod_new(NULL, NULL);
	if (!ctx) {
		PERROR("Unable to create kmod library context");
		ret = -ENOMEM;
		goto error;
	}

	kmod_set_log_fn(*ctx, log_kmod, NULL);
	ret = kmod_load_resources(*ctx);
	if (ret < 0) {
		ERR("Failed to load kmod library resources");
		goto error;
	}

error:
	return ret;
}

/**
 * @brief Loads the kernel modules in \p modules
 *
 * @param modules	List of modules to load
 * @param entries	Number of modules in the list
 *
 * If the modules are required, we will return with error after the
 * first failed module load, otherwise we continue loading.
 *
 * @returns		\c 0 on success
 * 			\c < 0 on error
 */
static int modprobe_lttng(struct kern_modules_param *modules,
		int entries)
{
	int ret = 0, i;
	struct kmod_ctx *ctx;

	ret = setup_kmod_ctx(&ctx);
	if (ret < 0) {
		goto error;
	}

	for (i = 0; i < entries; i++) {
		struct kmod_module *mod = NULL;

		ret = kmod_module_new_from_name(ctx, modules[i].name, &mod);
		if (ret < 0) {
			PERROR("Failed to create kmod module for %s", modules[i].name);
			goto error;
		}

		ret = kmod_module_probe_insert_module(mod, 0,
				NULL, NULL, NULL, NULL);
		if (ret == -EEXIST) {
			DBG("Module %s is already loaded", modules[i].name);
			ret = 0;
		} else if (ret < 0) {
			if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED) {
				ERR("Unable to load required module %s",
						modules[i].name);
				goto error;
			} else {
				DBG("Unable to load optional module %s; continuing",
						modules[i].name);
				ret = 0;
			}
		} else {
			DBG("Modprobe successfully %s", modules[i].name);
			modules[i].loaded = true;
		}

		kmod_module_unref(mod);
	}

error:
	if (ctx) {
		kmod_unref(ctx);
	}
	return ret;
}

/**
 * @brief Recursively unload modules.
 *
 * This function implements the same modules unloading behavior as
 * 'modprobe -r' or rmmod, it will recursevily go trought the \p module
 * dependencies and unload modules with a refcount of 0.
 *
 * @param mod		The module to unload
 *
 * @returns		\c 0 on success
 * 			\c < 0 on error
 */
static int rmmod_recurse(struct kmod_module *mod) {
	int ret = 0;
	struct kmod_list *deps, *itr;

	if (kmod_module_get_initstate(mod) == KMOD_MODULE_BUILTIN) {
		DBG("Module %s is builtin", kmod_module_get_name(mod));
		return ret;
	}

	ret = kmod_module_remove_module(mod, 0);

	deps = kmod_module_get_dependencies(mod);
	if (deps != NULL) {
		kmod_list_foreach(itr, deps) {
			struct kmod_module *dep = kmod_module_get_module(itr);
			if (kmod_module_get_refcnt(dep) == 0) {
				DBG("Recursive remove module %s",
						kmod_module_get_name(dep));
				rmmod_recurse(dep);
			}
			kmod_module_unref(dep);
		}
		kmod_module_unref_list(deps);
	}

	return ret;
}

/**
 * @brief Unloads the kernel modules in \p modules
 *
 * @param modules	List of modules to unload
 * @param entries	Number of modules in the list
 *
 */
static void modprobe_remove_lttng(const struct kern_modules_param *modules,
		int entries)
{
	int ret = 0, i;
	struct kmod_ctx *ctx;

	ret = setup_kmod_ctx(&ctx);
	if (ret < 0) {
		goto error;
	}

	for (i = entries - 1; i >= 0; i--) {
		struct kmod_module *mod = NULL;

		if (!modules[i].loaded) {
			continue;
		}

		ret = kmod_module_new_from_name(ctx, modules[i].name, &mod);
		if (ret < 0) {
			PERROR("Failed to create kmod module for %s", modules[i].name);
			goto error;
		}

		ret = rmmod_recurse(mod);
		if (ret == -EEXIST) {
			DBG("Module %s is not in kernel.", modules[i].name);
		} else if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED && ret < 0) {
			ERR("Unable to remove module %s", modules[i].name);
		} else {
			DBG("Modprobe removal successful %s",
				modules[i].name);
		}

		kmod_module_unref(mod);
	}

error:
	if (ctx) {
		kmod_unref(ctx);
	}
}

#else /* HAVE_KMOD */

static int modprobe_lttng(struct kern_modules_param *modules,
		int entries)
{
	int ret = 0, i;
	char modprobe[256];

	for (i = 0; i < entries; i++) {
		ret = snprintf(modprobe, sizeof(modprobe),
				"/sbin/modprobe %s%s",
				modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED ? "" : "-q ",
				modules[i].name);
		if (ret < 0) {
			PERROR("snprintf modprobe");
			goto error;
		}
		modprobe[sizeof(modprobe) - 1] = '\0';
		ret = system(modprobe);
		if (ret == -1) {
			if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED) {
				ERR("Unable to launch modprobe for required module %s",
						modules[i].name);
				goto error;
			} else {
				DBG("Unable to launch modprobe for optional module %s; continuing",
						modules[i].name);
				ret = 0;
			}
		} else if (WEXITSTATUS(ret) != 0) {
			if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED) {
				ERR("Unable to load required module %s",
						modules[i].name);
				goto error;
			} else {
				DBG("Unable to load optional module %s; continuing",
						modules[i].name);
				ret = 0;
			}
		} else {
			DBG("Modprobe successfully %s", modules[i].name);
			modules[i].loaded = true;
		}
	}

error:
	return ret;
}

static void modprobe_remove_lttng(const struct kern_modules_param *modules,
		int entries)
{
	int ret = 0, i;
	char modprobe[256];

	for (i = entries - 1; i >= 0; i--) {
		if (!modules[i].loaded) {
			continue;
		}
		ret = snprintf(modprobe, sizeof(modprobe),
				"/sbin/modprobe -r -q %s",
				modules[i].name);
		if (ret < 0) {
			PERROR("snprintf modprobe -r");
			return;
		}
		modprobe[sizeof(modprobe) - 1] = '\0';
		ret = system(modprobe);
		if (ret == -1) {
			ERR("Unable to launch modprobe -r for module %s",
					modules[i].name);
		} else if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED && WEXITSTATUS(ret) != 0) {
			ERR("Unable to remove module %s",
					modules[i].name);
		} else {
			DBG("Modprobe removal successful %s",
					modules[i].name);
		}
	}
}

#endif /* HAVE_KMOD */

/*
 * Remove control kernel module(s) in reverse load order.
 */
void modprobe_remove_lttng_control(void)
{
	modprobe_remove_lttng(kern_modules_control_core,
			ARRAY_SIZE(kern_modules_control_core));
}

static void free_probes(void)
{
	int i;

	if (!probes) {
		return;
	}
	for (i = 0; i < nr_probes; ++i) {
		free(probes[i].name);
	}
	free(probes);
	probes = NULL;
	nr_probes = 0;
}

/*
 * Remove data kernel modules in reverse load order.
 */
void modprobe_remove_lttng_data(void)
{
	if (!probes) {
		return;
	}

	modprobe_remove_lttng(probes, nr_probes);
	free_probes();
}

/*
 * Remove all kernel modules in reverse order.
 */
void modprobe_remove_lttng_all(void)
{
	modprobe_remove_lttng_data();
	modprobe_remove_lttng_control();
}

/*
 * Load control kernel module(s).
 */
int modprobe_lttng_control(void)
{
	return modprobe_lttng(kern_modules_control_core,
			ARRAY_SIZE(kern_modules_control_core));
}

/**
 * Grow global list of probes (double capacity or set it to 1 if
 * currently 0 and copy existing data).
 */
static int grow_probes(void)
{
	int i;
	struct kern_modules_param *tmp_probes;

	/* Initialize capacity to 1 if 0. */
	if (probes_capacity == 0) {
		probes = zmalloc(sizeof(*probes));
		if (!probes) {
			PERROR("malloc probe list");
			return -ENOMEM;
		}

		probes_capacity = 1;
		return 0;
	}

	/* Double size. */
	probes_capacity *= 2;

	tmp_probes = zmalloc(sizeof(*tmp_probes) * probes_capacity);
	if (!tmp_probes) {
		PERROR("malloc probe list");
		return -ENOMEM;
	}

	for (i = 0; i < nr_probes; ++i) {
		/* Ownership of 'name' field is transferred. */
		tmp_probes[i] = probes[i];
	}

	/* Replace probes with larger copy. */
	free(probes);
	probes = tmp_probes;

	return 0;
}

/*
 * Appends a comma-separated list of probes to the global list
 * of probes.
 */
static int append_list_to_probes(const char *list)
{
	char *next;
	int ret;
	char *tmp_list, *cur_list;

	assert(list);

	cur_list = tmp_list = strdup(list);
	if (!tmp_list) {
		PERROR("strdup temp list");
		return -ENOMEM;
	}

	for (;;) {
		size_t name_len;
		struct kern_modules_param *cur_mod;

		next = strtok(cur_list, ",");
		if (!next) {
			break;
		}
		cur_list = NULL;

		/* filter leading spaces */
		while (*next == ' ') {
			next++;
		}

		if (probes_capacity <= nr_probes) {
			ret = grow_probes();
			if (ret) {
				goto error;
			}
		}

		/* Length 13 is "lttng-probe-" + \0 */
		name_len = strlen(next) + 13;

		cur_mod = &probes[nr_probes];
		cur_mod->name = zmalloc(name_len);
		if (!cur_mod->name) {
			PERROR("malloc probe list");
			ret = -ENOMEM;
			goto error;
		}

		ret = snprintf(cur_mod->name, name_len, "lttng-probe-%s", next);
		if (ret < 0) {
			PERROR("snprintf modprobe name");
			ret = -ENOMEM;
			goto error;
		}

		cur_mod->load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL;

		nr_probes++;
	}

	free(tmp_list);
	return 0;

error:
	free(tmp_list);
	free_probes();
	return ret;
}

/*
 * Load data kernel module(s).
 */
int modprobe_lttng_data(void)
{
	int ret, i;
	char *list;

	/*
	 * Base probes: either from command line option, environment
	 * variable or default list.
	 */
	list = config.kmod_probes_list.value;
	if (list) {
		/* User-specified probes. */
		ret = append_list_to_probes(list);
		if (ret) {
			return ret;
		}
	} else {
		/* Default probes. */
		int def_len = ARRAY_SIZE(kern_modules_probes_default);

		probes = zmalloc(sizeof(*probes) * def_len);
		if (!probes) {
			PERROR("malloc probe list");
			return -ENOMEM;
		}

		nr_probes = probes_capacity = def_len;

		for (i = 0; i < def_len; ++i) {
			char* name = strdup(kern_modules_probes_default[i].name);

			if (!name) {
				PERROR("strdup probe item");
				ret = -ENOMEM;
				goto error;
			}

			probes[i].name = name;
			probes[i].load_policy = kern_modules_probes_default[i].load_policy;
		}
	}

	/*
	 * Extra modules? Append them to current probes list.
	 */
	list = config.kmod_extra_probes_list.value;
	if (list) {
		ret = append_list_to_probes(list);
		if (ret) {
			goto error;
		}
	}

	/*
	 * Load probes modules now.
	 */
	ret = modprobe_lttng(probes, nr_probes);
	if (ret) {
		goto error;
	}
	return ret;

error:
	free_probes();
	return ret;
}
Commit	Line	Data
096102bd	1	/*
ab5be9fa MJ	2	* Copyright (C) 2011 David Goulet <dgoulet@efficios.com>
ab5be9fa MJ	3	* Copyright (C) 2014 Jan Glauber <jan.glauber@gmail.com>
096102bd	4	*
ab5be9fa	5	* SPDX-License-Identifier: GPL-2.0-only
096102bd	6	*
096102bd DG	7	*/
096102bd DG	8
d11b2027 MJ	9	/**
	10	* @file modprobe.c
	11	*
	12	* @brief modprobe related functions.
	13	*
	14	*/
	15
6c1c0768	16	#define _LGPL_SOURCE
c9d42407	17	#include <assert.h>
096102bd DG	18	#include <stdio.h>
	19	#include <stdlib.h>
	20	#include <sys/wait.h>
	21
	22	#include <common/common.h>
fbb9748b	23	#include <common/utils.h>
096102bd DG	24
	25	#include "modprobe.h"
	26	#include "kern-modules.h"
e6142f2e	27	#include "lttng-sessiond.h"
096102bd	28
ab57d7d3 JG	29	/* LTTng kernel tracer mandatory core modules list */
ab57d7d3 JG	30	struct kern_modules_param kern_modules_control_core[] = {
adfe4f5e JG	31	{
	32	.name = (char *) "lttng-ring-buffer-client-discard",
	33	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	34	},
	35	{
	36	.name = (char *) "lttng-ring-buffer-client-overwrite",
	37	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	38	},
	39	{
	40	.name = (char *) "lttng-ring-buffer-metadata-client",
	41	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	42	},
	43	{
	44	.name = (char *) "lttng-ring-buffer-client-mmap-discard",
	45	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	46	},
	47	{
	48	.name = (char *) "lttng-ring-buffer-client-mmap-overwrite",
	49	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	50	},
	51	{
	52	.name = (char *) "lttng-ring-buffer-metadata-mmap-client",
	53	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED,
	54	},
87a15032 JR	55	{
	56	.name = (char *) "lttng-ring-buffer-event_notifier-client",
	57	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	58	},
ab57d7d3 JG	59	};
ab57d7d3 JG	60
adfe4f5e	61	/* LTTng kerneltracer probe modules list */
fbb9748b	62	struct kern_modules_param kern_modules_probes_default[] = {
adfe4f5e JG	63	{
	64	.name = (char *) "lttng-probe-asoc",
	65	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	66	},
	67	{
	68	.name = (char *) "lttng-probe-block",
	69	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	70	},
	71	{
	72	.name = (char *) "lttng-probe-btrfs",
	73	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	74	},
	75	{
	76	.name = (char *) "lttng-probe-compaction",
	77	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	78	},
	79	{
	80	.name = (char *) "lttng-probe-ext3",
	81	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	82	},
	83	{
	84	.name = (char *) "lttng-probe-ext4",
	85	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	86	},
	87	{
	88	.name = (char *) "lttng-probe-gpio",
	89	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	90	},
	91	{
	92	.name = (char *) "lttng-probe-i2c",
	93	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	94	},
	95	{
	96	.name = (char *) "lttng-probe-irq",
	97	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	98	},
	99	{
	100	.name = (char *) "lttng-probe-jbd",
	101	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	102	},
	103	{
	104	.name = (char *) "lttng-probe-jbd2",
	105	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	106	},
	107	{
	108	.name = (char *) "lttng-probe-kmem",
	109	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	110	},
	111	{
	112	.name = (char *) "lttng-probe-kvm",
	113	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	114	},
	115	{
	116	.name = (char *) "lttng-probe-kvm-x86",
	117	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	118	},
	119	{
	120	.name = (char *) "lttng-probe-kvm-x86-mmu",
	121	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	122	},
	123	{
	124	.name = (char *) "lttng-probe-lock",
	125	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
	126	},
127	{
128	.name = (char *) "lttng-probe-module",
129	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
130	},
131	{
132	.name = (char *) "lttng-probe-napi",
133	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
134	},
135	{
136	.name = (char *) "lttng-probe-net",
137	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
138	},
139	{
140	.name = (char *) "lttng-probe-power",
141	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
142	},
143	{
144	.name = (char *) "lttng-probe-preemptirq",
145	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
146	},
147	{
148	.name = (char *) "lttng-probe-printk",
149	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
150	},
151	{
152	.name = (char *) "lttng-probe-random",
153	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
154	},
155	{
156	.name = (char *) "lttng-probe-rcu",
157	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
158	},
159	{
160	.name = (char *) "lttng-probe-regmap",
161	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
162	},
163	{
164	.name = (char *) "lttng-probe-regulator",
165	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
166	},
167	{
168	.name = (char *) "lttng-probe-rpm",
169	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
170	},
171	{
172	.name = (char *) "lttng-probe-sched",
173	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
174	},
175	{
176	.name = (char *) "lttng-probe-scsi",
177	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
178	},
179	{
180	.name = (char *) "lttng-probe-signal",
181	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
182	},
183	{
184	.name = (char *) "lttng-probe-skb",
185	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
186	},
187	{
188	.name = (char *) "lttng-probe-sock",
189	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
190	},
191	{
192	.name = (char *) "lttng-probe-statedump",
193	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
194	},
195	{
196	.name = (char *) "lttng-probe-sunrpc",
197	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
198	},
199	{
200	.name = (char *) "lttng-probe-timer",
201	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
202	},
203	{
204	.name = (char *) "lttng-probe-udp",
205	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
206	},
207	{
208	.name = (char *) "lttng-probe-vmscan",
209	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
210	},
211	{
212	.name = (char *) "lttng-probe-v4l2",
213	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
214	},
215	{
216	.name = (char *) "lttng-probe-workqueue",
217	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
218	},
219	{
220	.name = (char *) "lttng-probe-writeback",
221	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
222	},
223	{
224	.name = (char *) "lttng-probe-x86-irq-vectors",
225	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
226	},
227	{
228	.name = (char *) "lttng-probe-x86-exceptions",
229	.load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL,
230	},
096102bd DG	231	};
096102bd DG	232
fbb9748b JG	233	/* dynamic probe modules list */
	234	static struct kern_modules_param *probes;
	235	static int nr_probes;
c9d42407	236	static int probes_capacity;
fbb9748b	237
234170ac UTL	238	#if HAVE_KMOD
234170ac UTL	239	#include <libkmod.h>
866c17ce	240
d11b2027 MJ	241	/**
	242	* @brief Logging function for libkmod integration.
	243	*/
234170ac UTL	244	static void log_kmod(void data, int priority, const char file, int line,
	245	const char fn, const char format, va_list args)
	246	{
	247	char *str;
	248
	249	if (vasprintf(&str, format, args) < 0) {
	250	return;
	251	}
	252
	253	DBG("libkmod: %s", str);
	254	free(str);
	255	}
866c17ce	256
d11b2027 MJ	257	/**
	258	* @brief Setup the libkmod context.
	259	*
	260	* Create the context, add a custom logging function and preload the
	261	* ressources for faster operation.
	262	*
	263	* @returns \c 0 on success
	264	* \c < 0 on error
	265	*/
866c17ce	266	static int setup_kmod_ctx(struct kmod_ctx **ctx)
234170ac	267	{
866c17ce	268	int ret = 0;
234170ac	269
866c17ce	270	*ctx = kmod_new(NULL, NULL);
234170ac UTL	271	if (!ctx) {
	272	PERROR("Unable to create kmod library context");
	273	ret = -ENOMEM;
	274	goto error;
	275	}
	276
866c17ce MJ	277	kmod_set_log_fn(*ctx, log_kmod, NULL);
	278	ret = kmod_load_resources(*ctx);
	279	if (ret < 0) {
	280	ERR("Failed to load kmod library resources");
	281	goto error;
	282	}
	283
	284	error:
	285	return ret;
	286	}
	287
d11b2027 MJ	288	/**
	289	* @brief Loads the kernel modules in \p modules
	290	*
	291	* @param modules List of modules to load
	292	* @param entries Number of modules in the list
d11b2027 MJ	293	*
	294	* If the modules are required, we will return with error after the
	295	* first failed module load, otherwise we continue loading.
	296	*
	297	* @returns \c 0 on success
	298	* \c < 0 on error
	299	*/
866c17ce	300	static int modprobe_lttng(struct kern_modules_param *modules,
adfe4f5e	301	int entries)
866c17ce MJ	302	{
	303	int ret = 0, i;
	304	struct kmod_ctx *ctx;
	305
	306	ret = setup_kmod_ctx(&ctx);
	307	if (ret < 0) {
	308	goto error;
	309	}
234170ac UTL	310
	311	for (i = 0; i < entries; i++) {
	312	struct kmod_module *mod = NULL;
	313
	314	ret = kmod_module_new_from_name(ctx, modules[i].name, &mod);
	315	if (ret < 0) {
	316	PERROR("Failed to create kmod module for %s", modules[i].name);
	317	goto error;
	318	}
	319
0b1e16b8	320	ret = kmod_module_probe_insert_module(mod, 0,
234170ac	321	NULL, NULL, NULL, NULL);
0b1e16b8 MJ	322	if (ret == -EEXIST) {
	323	DBG("Module %s is already loaded", modules[i].name);
	324	ret = 0;
	325	} else if (ret < 0) {
adfe4f5e	326	if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED) {
16c2e854 PP	327	ERR("Unable to load required module %s",
	328	modules[i].name);
	329	goto error;
	330	} else {
	331	DBG("Unable to load optional module %s; continuing",
	332	modules[i].name);
	333	ret = 0;
	334	}
234170ac UTL	335	} else {
234170ac UTL	336	DBG("Modprobe successfully %s", modules[i].name);
4ad664a0	337	modules[i].loaded = true;
234170ac UTL	338	}
	339
	340	kmod_module_unref(mod);
	341	}
	342
	343	error:
	344	if (ctx) {
	345	kmod_unref(ctx);
	346	}
	347	return ret;
	348	}
	349
d11b2027 MJ	350	/**
	351	* @brief Recursively unload modules.
	352	*
	353	* This function implements the same modules unloading behavior as
	354	* 'modprobe -r' or rmmod, it will recursevily go trought the \p module
	355	* dependencies and unload modules with a refcount of 0.
	356	*
	357	* @param mod The module to unload
	358	*
	359	* @returns \c 0 on success
	360	* \c < 0 on error
	361	*/
866c17ce MJ	362	static int rmmod_recurse(struct kmod_module *mod) {
	363	int ret = 0;
	364	struct kmod_list deps, itr;
	365
	366	if (kmod_module_get_initstate(mod) == KMOD_MODULE_BUILTIN) {
	367	DBG("Module %s is builtin", kmod_module_get_name(mod));
	368	return ret;
	369	}
	370
	371	ret = kmod_module_remove_module(mod, 0);
	372
	373	deps = kmod_module_get_dependencies(mod);
	374	if (deps != NULL) {
	375	kmod_list_foreach(itr, deps) {
	376	struct kmod_module *dep = kmod_module_get_module(itr);
	377	if (kmod_module_get_refcnt(dep) == 0) {
	378	DBG("Recursive remove module %s",
	379	kmod_module_get_name(dep));
	380	rmmod_recurse(dep);
	381	}
	382	kmod_module_unref(dep);
	383	}
	384	kmod_module_unref_list(deps);
	385	}
	386
	387	return ret;
	388	}
	389
d11b2027 MJ	390	/**
	391	* @brief Unloads the kernel modules in \p modules
	392	*
	393	* @param modules List of modules to unload
	394	* @param entries Number of modules in the list
d11b2027 MJ	395	*
d11b2027 MJ	396	*/
866c17ce	397	static void modprobe_remove_lttng(const struct kern_modules_param *modules,
adfe4f5e	398	int entries)
866c17ce MJ	399	{
	400	int ret = 0, i;
	401	struct kmod_ctx *ctx;
	402
	403	ret = setup_kmod_ctx(&ctx);
	404	if (ret < 0) {
	405	goto error;
	406	}
	407
	408	for (i = entries - 1; i >= 0; i--) {
	409	struct kmod_module *mod = NULL;
	410
4ad664a0 JG	411	if (!modules[i].loaded) {
	412	continue;
	413	}
	414
866c17ce MJ	415	ret = kmod_module_new_from_name(ctx, modules[i].name, &mod);
	416	if (ret < 0) {
	417	PERROR("Failed to create kmod module for %s", modules[i].name);
	418	goto error;
	419	}
	420
	421	ret = rmmod_recurse(mod);
	422	if (ret == -EEXIST) {
	423	DBG("Module %s is not in kernel.", modules[i].name);
adfe4f5e	424	} else if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED && ret < 0) {
866c17ce MJ	425	ERR("Unable to remove module %s", modules[i].name);
	426	} else {
	427	DBG("Modprobe removal successful %s",
	428	modules[i].name);
	429	}
	430
	431	kmod_module_unref(mod);
	432	}
	433
	434	error:
	435	if (ctx) {
	436	kmod_unref(ctx);
	437	}
	438	}
	439
234170ac UTL	440	#else /* HAVE_KMOD */
234170ac UTL	441
fbb9748b	442	static int modprobe_lttng(struct kern_modules_param *modules,
adfe4f5e	443	int entries)
096102bd DG	444	{
	445	int ret = 0, i;
	446	char modprobe[256];
	447
e23b81ed	448	for (i = 0; i < entries; i++) {
096102bd DG	449	ret = snprintf(modprobe, sizeof(modprobe),
096102bd DG	450	"/sbin/modprobe %s%s",
adfe4f5e	451	modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED ? "" : "-q ",
e23b81ed	452	modules[i].name);
096102bd DG	453	if (ret < 0) {
	454	PERROR("snprintf modprobe");
	455	goto error;
	456	}
	457	modprobe[sizeof(modprobe) - 1] = '\0';
	458	ret = system(modprobe);
	459	if (ret == -1) {
adfe4f5e	460	if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED) {
16c2e854 PP	461	ERR("Unable to launch modprobe for required module %s",
	462	modules[i].name);
	463	goto error;
	464	} else {
	465	DBG("Unable to launch modprobe for optional module %s; continuing",
	466	modules[i].name);
	467	ret = 0;
	468	}
	469	} else if (WEXITSTATUS(ret) != 0) {
adfe4f5e	470	if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED) {
16c2e854 PP	471	ERR("Unable to load required module %s",
	472	modules[i].name);
	473	goto error;
	474	} else {
	475	DBG("Unable to load optional module %s; continuing",
	476	modules[i].name);
	477	ret = 0;
	478	}
096102bd	479	} else {
ab57d7d3	480	DBG("Modprobe successfully %s", modules[i].name);
355d2778	481	modules[i].loaded = true;
096102bd DG	482	}
	483	}
	484
	485	error:
	486	return ret;
	487	}
	488
35e090b7	489	static void modprobe_remove_lttng(const struct kern_modules_param *modules,
adfe4f5e	490	int entries)
35e090b7 MJ	491	{
	492	int ret = 0, i;
	493	char modprobe[256];
	494
	495	for (i = entries - 1; i >= 0; i--) {
4ad664a0 JG	496	if (!modules[i].loaded) {
	497	continue;
	498	}
35e090b7 MJ	499	ret = snprintf(modprobe, sizeof(modprobe),
	500	"/sbin/modprobe -r -q %s",
	501	modules[i].name);
	502	if (ret < 0) {
	503	PERROR("snprintf modprobe -r");
	504	return;
	505	}
	506	modprobe[sizeof(modprobe) - 1] = '\0';
	507	ret = system(modprobe);
	508	if (ret == -1) {
	509	ERR("Unable to launch modprobe -r for module %s",
	510	modules[i].name);
adfe4f5e	511	} else if (modules[i].load_policy == KERNEL_MODULE_PROPERTY_LOAD_POLICY_REQUIRED && WEXITSTATUS(ret) != 0) {
35e090b7 MJ	512	ERR("Unable to remove module %s",
	513	modules[i].name);
	514	} else {
	515	DBG("Modprobe removal successful %s",
	516	modules[i].name);
	517	}
	518	}
	519	}
	520
866c17ce MJ	521	#endif /* HAVE_KMOD */
866c17ce MJ	522
35e090b7 MJ	523	/*
	524	* Remove control kernel module(s) in reverse load order.
	525	*/
	526	void modprobe_remove_lttng_control(void)
	527	{
	528	modprobe_remove_lttng(kern_modules_control_core,
adfe4f5e	529	ARRAY_SIZE(kern_modules_control_core));
35e090b7 MJ	530	}
	531
	532	static void free_probes(void)
	533	{
	534	int i;
	535
	536	if (!probes) {
	537	return;
	538	}
	539	for (i = 0; i < nr_probes; ++i) {
	540	free(probes[i].name);
	541	}
	542	free(probes);
	543	probes = NULL;
	544	nr_probes = 0;
	545	}
	546
	547	/*
	548	* Remove data kernel modules in reverse load order.
	549	*/
	550	void modprobe_remove_lttng_data(void)
	551	{
	552	if (!probes) {
	553	return;
	554	}
adfe4f5e JG	555
adfe4f5e JG	556	modprobe_remove_lttng(probes, nr_probes);
35e090b7 MJ	557	free_probes();
	558	}
	559
	560	/*
	561	* Remove all kernel modules in reverse order.
	562	*/
	563	void modprobe_remove_lttng_all(void)
	564	{
	565	modprobe_remove_lttng_data();
	566	modprobe_remove_lttng_control();
	567	}
	568
e23b81ed JG	569	/*
	570	* Load control kernel module(s).
	571	*/
	572	int modprobe_lttng_control(void)
	573	{
adfe4f5e JG	574	return modprobe_lttng(kern_modules_control_core,
adfe4f5e JG	575	ARRAY_SIZE(kern_modules_control_core));
e23b81ed	576	}
ab57d7d3	577
c9d42407 PP	578	/**
	579	* Grow global list of probes (double capacity or set it to 1 if
	580	* currently 0 and copy existing data).
096102bd	581	*/
c9d42407	582	static int grow_probes(void)
096102bd	583	{
c9d42407 PP	584	int i;
c9d42407 PP	585	struct kern_modules_param *tmp_probes;
fbb9748b	586
c9d42407 PP	587	/* Initialize capacity to 1 if 0. */
	588	if (probes_capacity == 0) {
	589	probes = zmalloc(sizeof(*probes));
	590	if (!probes) {
	591	PERROR("malloc probe list");
	592	return -ENOMEM;
	593	}
	594
	595	probes_capacity = 1;
	596	return 0;
fbb9748b JG	597	}
fbb9748b JG	598
c9d42407 PP	599	/* Double size. */
	600	probes_capacity *= 2;
	601
	602	tmp_probes = zmalloc(sizeof(tmp_probes) probes_capacity);
	603	if (!tmp_probes) {
fbb9748b JG	604	PERROR("malloc probe list");
	605	return -ENOMEM;
	606	}
	607
c9d42407	608	for (i = 0; i < nr_probes; ++i) {
adfe4f5e JG	609	/* Ownership of 'name' field is transferred. */
adfe4f5e JG	610	tmp_probes[i] = probes[i];
c9d42407 PP	611	}
	612
	613	/* Replace probes with larger copy. */
	614	free(probes);
	615	probes = tmp_probes;
	616
	617	return 0;
	618	}
	619
	620	/*
	621	* Appends a comma-separated list of probes to the global list
	622	* of probes.
	623	*/
	624	static int append_list_to_probes(const char *list)
	625	{
	626	char *next;
d3c04b7c	627	int ret;
44603c80	628	char tmp_list, cur_list;
c9d42407 PP	629
	630	assert(list);
	631
44603c80	632	cur_list = tmp_list = strdup(list);
c9d42407 PP	633	if (!tmp_list) {
	634	PERROR("strdup temp list");
	635	return -ENOMEM;
	636	}
	637
	638	for (;;) {
fbb9748b	639	size_t name_len;
c9d42407	640	struct kern_modules_param *cur_mod;
fbb9748b	641
44603c80	642	next = strtok(cur_list, ",");
fbb9748b	643	if (!next) {
c9d42407	644	break;
fbb9748b	645	}
44603c80	646	cur_list = NULL;
fbb9748b JG	647
	648	/* filter leading spaces */
	649	while (*next == ' ') {
	650	next++;
	651	}
	652
c9d42407 PP	653	if (probes_capacity <= nr_probes) {
	654	ret = grow_probes();
	655	if (ret) {
398d5459	656	goto error;
c9d42407 PP	657	}
	658	}
	659
fbb9748b JG	660	/* Length 13 is "lttng-probe-" + \0 */
	661	name_len = strlen(next) + 13;
	662
d3c04b7c	663	cur_mod = &probes[nr_probes];
c9d42407 PP	664	cur_mod->name = zmalloc(name_len);
c9d42407 PP	665	if (!cur_mod->name) {
fbb9748b	666	PERROR("malloc probe list");
398d5459 MD	667	ret = -ENOMEM;
398d5459 MD	668	goto error;
fbb9748b JG	669	}
fbb9748b JG	670
c9d42407	671	ret = snprintf(cur_mod->name, name_len, "lttng-probe-%s", next);
fbb9748b JG	672	if (ret < 0) {
fbb9748b JG	673	PERROR("snprintf modprobe name");
398d5459 MD	674	ret = -ENOMEM;
398d5459 MD	675	goto error;
fbb9748b	676	}
c9d42407	677
adfe4f5e JG	678	cur_mod->load_policy = KERNEL_MODULE_PROPERTY_LOAD_POLICY_OPTIONAL;
adfe4f5e JG	679
c9d42407	680	nr_probes++;
fbb9748b JG	681	}
fbb9748b JG	682
c9d42407	683	free(tmp_list);
c9d42407	684	return 0;
398d5459 MD	685
	686	error:
	687	free(tmp_list);
	688	free_probes();
	689	return ret;
c9d42407 PP	690	}
	691
	692	/*
	693	* Load data kernel module(s).
	694	*/
	695	int modprobe_lttng_data(void)
	696	{
	697	int ret, i;
	698	char *list;
	699
	700	/*
	701	* Base probes: either from command line option, environment
	702	* variable or default list.
	703	*/
e6142f2e	704	list = config.kmod_probes_list.value;
c9d42407 PP	705	if (list) {
	706	/* User-specified probes. */
	707	ret = append_list_to_probes(list);
c9d42407 PP	708	if (ret) {
	709	return ret;
	710	}
	711	} else {
	712	/* Default probes. */
	713	int def_len = ARRAY_SIZE(kern_modules_probes_default);
c9d42407	714
62e0422e	715	probes = zmalloc(sizeof(probes) def_len);
c9d42407 PP	716	if (!probes) {
	717	PERROR("malloc probe list");
	718	return -ENOMEM;
	719	}
	720
	721	nr_probes = probes_capacity = def_len;
	722
	723	for (i = 0; i < def_len; ++i) {
	724	char* name = strdup(kern_modules_probes_default[i].name);
	725
	726	if (!name) {
	727	PERROR("strdup probe item");
398d5459 MD	728	ret = -ENOMEM;
398d5459 MD	729	goto error;
c9d42407 PP	730	}
	731
	732	probes[i].name = name;
adfe4f5e	733	probes[i].load_policy = kern_modules_probes_default[i].load_policy;
c9d42407 PP	734	}
	735	}
	736
	737	/*
	738	* Extra modules? Append them to current probes list.
	739	*/
e6142f2e	740	list = config.kmod_extra_probes_list.value;
c9d42407 PP	741	if (list) {
	742	ret = append_list_to_probes(list);
	743	if (ret) {
398d5459	744	goto error;
c9d42407 PP	745	}
	746	}
	747
	748	/*
	749	* Load probes modules now.
	750	*/
adfe4f5e	751	ret = modprobe_lttng(probes, nr_probes);
398d5459 MD	752	if (ret) {
	753	goto error;
	754	}
	755	return ret;
	756
	757	error:
	758	free_probes();
	759	return ret;
096102bd	760	}