/*
* Copyright (C) 2011 - David Goulet <dgoulet@efficios.com>
+ * 2014 - Jan Glauber <jan.glauber@gmail.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,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#define _GNU_SOURCE
+/**
+ * @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"
-/* MUST be loaded first */
-const struct kern_modules_param kern_modules_control[] = {
- { "lttng-tracer", 1 },
+#define LTTNG_MOD_REQUIRED 1
+#define LTTNG_MOD_OPTIONAL 0
+
+/* LTTng kernel tracer mandatory core modules list */
+struct kern_modules_param kern_modules_control_core[] = {
+ { "lttng-ring-buffer-client-discard" },
+ { "lttng-ring-buffer-client-overwrite" },
+ { "lttng-ring-buffer-metadata-client" },
+ { "lttng-ring-buffer-client-mmap-discard" },
+ { "lttng-ring-buffer-client-mmap-overwrite" },
+ { "lttng-ring-buffer-metadata-mmap-client" },
};
-/* LTTng kernel tracer modules list */
-const struct kern_modules_param kern_modules_list[] = {
- { "lttng-ftrace", 0 },
- { "lttng-kprobes", 0 },
- { "lttng-kretprobes", 0 },
- { "lttng-lib-ring-buffer", 1 },
- { "lttng-ring-buffer-client-discard", 1 },
- { "lttng-ring-buffer-client-overwrite", 1 },
- { "lttng-ring-buffer-metadata-client", 1 },
- { "lttng-ring-buffer-client-mmap-discard", 1 },
- { "lttng-ring-buffer-client-mmap-overwrite", 1 },
- { "lttng-ring-buffer-metadata-mmap-client", 1 },
- { "lttng-types", 0 },
- { "lttng-probe-asoc", 0 },
- { "lttng-probe-block", 0 },
- { "lttng-probe-btrfs", 0 },
- { "lttng-probe-compaction", 0 },
- { "lttng-probe-ext3", 0 },
- { "lttng-probe-ext4", 0 },
- { "lttng-probe-gpio", 0 },
- { "lttng-probe-irq", 0 },
- { "lttng-probe-jbd", 0 },
- { "lttng-probe-jbd2", 0 },
- { "lttng-probe-kmem", 0 },
- { "lttng-probe-kvm", 0 },
- { "lttng-probe-kvm-x86", 0 },
- { "lttng-probe-kvm-x86-mmu", 0 },
- { "lttng-probe-lock", 0 },
- { "lttng-probe-module", 0 },
- { "lttng-probe-napi", 0 },
- { "lttng-probe-net", 0 },
- { "lttng-probe-power", 0 },
- { "lttng-probe-printk", 0 },
- { "lttng-probe-random", 0 },
- { "lttng-probe-rcu", 0 },
- { "lttng-probe-regmap", 0 },
- { "lttng-probe-regulator", 0 },
- { "lttng-probe-rpm", 0 },
- { "lttng-probe-sched", 0 },
- { "lttng-probe-scsi", 0 },
- { "lttng-probe-signal", 0 },
- { "lttng-probe-skb", 0 },
- { "lttng-probe-sock", 0 },
- { "lttng-probe-statedump", 0 },
- { "lttng-probe-sunrpc", 0 },
- { "lttng-probe-timer", 0 },
- { "lttng-probe-udp", 0 },
- { "lttng-probe-vmscan", 0 },
- { "lttng-probe-v4l2", 0 },
- { "lttng-probe-workqueue", 0 },
- { "lttng-probe-writeback", 0 },
+/* LTTng kernel tracer probe modules list */
+struct kern_modules_param kern_modules_probes_default[] = {
+ { "lttng-probe-asoc" },
+ { "lttng-probe-block" },
+ { "lttng-probe-btrfs" },
+ { "lttng-probe-compaction" },
+ { "lttng-probe-ext3" },
+ { "lttng-probe-ext4" },
+ { "lttng-probe-gpio" },
+ { "lttng-probe-i2c" },
+ { "lttng-probe-irq" },
+ { "lttng-probe-jbd" },
+ { "lttng-probe-jbd2" },
+ { "lttng-probe-kmem" },
+ { "lttng-probe-kvm" },
+ { "lttng-probe-kvm-x86" },
+ { "lttng-probe-kvm-x86-mmu" },
+ { "lttng-probe-lock" },
+ { "lttng-probe-module" },
+ { "lttng-probe-napi" },
+ { "lttng-probe-net" },
+ { "lttng-probe-power" },
+ { "lttng-probe-printk" },
+ { "lttng-probe-random" },
+ { "lttng-probe-rcu" },
+ { "lttng-probe-regmap" },
+ { "lttng-probe-regulator" },
+ { "lttng-probe-rpm" },
+ { "lttng-probe-sched" },
+ { "lttng-probe-scsi" },
+ { "lttng-probe-signal" },
+ { "lttng-probe-skb" },
+ { "lttng-probe-sock" },
+ { "lttng-probe-statedump" },
+ { "lttng-probe-sunrpc" },
+ { "lttng-probe-timer" },
+ { "lttng-probe-udp" },
+ { "lttng-probe-vmscan" },
+ { "lttng-probe-v4l2" },
+ { "lttng-probe-workqueue" },
+ { "lttng-probe-writeback" },
+ { "lttng-probe-x86-irq-vectors" },
+ { "lttng-probe-x86-exceptions" },
};
-/*
- * Remove control kernel module(s) in reverse load order.
+/* 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.
*/
-void modprobe_remove_lttng_control(void)
+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
+ * @param required Are the modules required or optionnal
+ *
+ * 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 required)
+{
+ 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 (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
+ * @param required Are the modules required or optionnal
+ *
+ */
+static void modprobe_remove_lttng(const struct kern_modules_param *modules,
+ int entries, int required)
+{
+ 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 (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 required)
{
int ret = 0, i;
char modprobe[256];
- for (i = ARRAY_SIZE(kern_modules_control) - 1; i >= 0; i--) {
+ for (i = 0; i < entries; i++) {
ret = snprintf(modprobe, sizeof(modprobe),
- "/sbin/modprobe -r -q %s",
- kern_modules_control[i].name);
+ "/sbin/modprobe %s%s",
+ required ? "" : "-q ",
+ modules[i].name);
if (ret < 0) {
- PERROR("snprintf modprobe -r");
+ PERROR("snprintf modprobe");
goto error;
}
modprobe[sizeof(modprobe) - 1] = '\0';
ret = system(modprobe);
if (ret == -1) {
- ERR("Unable to launch modprobe -r for module %s",
- kern_modules_control[i].name);
- } else if (kern_modules_control[i].required
- && WEXITSTATUS(ret) != 0) {
- ERR("Unable to remove module %s",
- kern_modules_control[i].name);
+ if (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 (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 removal successful %s",
- kern_modules_control[i].name);
+ DBG("Modprobe successfully %s", modules[i].name);
+ modules[i].loaded = true;
}
}
error:
- return;
+ return ret;
}
-/*
- * Remove data kernel modules in reverse load order.
- */
-void modprobe_remove_lttng_data(void)
+static void modprobe_remove_lttng(const struct kern_modules_param *modules,
+ int entries, int required)
{
int ret = 0, i;
char modprobe[256];
- for (i = ARRAY_SIZE(kern_modules_list) - 1; i >= 0; i--) {
+ for (i = entries - 1; i >= 0; i--) {
+ if (!modules[i].loaded) {
+ continue;
+ }
ret = snprintf(modprobe, sizeof(modprobe),
"/sbin/modprobe -r -q %s",
- kern_modules_list[i].name);
+ modules[i].name);
if (ret < 0) {
PERROR("snprintf modprobe -r");
- goto error;
+ return;
}
modprobe[sizeof(modprobe) - 1] = '\0';
ret = system(modprobe);
if (ret == -1) {
ERR("Unable to launch modprobe -r for module %s",
- kern_modules_list[i].name);
- } else if (kern_modules_list[i].required
- && WEXITSTATUS(ret) != 0) {
+ modules[i].name);
+ } else if (required && WEXITSTATUS(ret) != 0) {
ERR("Unable to remove module %s",
- kern_modules_list[i].name);
+ modules[i].name);
} else {
DBG("Modprobe removal successful %s",
- kern_modules_list[i].name);
+ modules[i].name);
}
}
+}
-error:
- return;
+#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),
+ LTTNG_MOD_REQUIRED);
+}
+
+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, LTTNG_MOD_OPTIONAL);
+ free_probes();
}
/*
*/
int modprobe_lttng_control(void)
{
- int ret = 0, i;
- char modprobe[256];
+ int ret;
- for (i = 0; i < ARRAY_SIZE(kern_modules_control); i++) {
- ret = snprintf(modprobe, sizeof(modprobe),
- "/sbin/modprobe %s%s",
- kern_modules_control[i].required ? "" : "-q ",
- kern_modules_control[i].name);
- if (ret < 0) {
- PERROR("snprintf modprobe");
+ ret = modprobe_lttng(kern_modules_control_core,
+ ARRAY_SIZE(kern_modules_control_core),
+ LTTNG_MOD_REQUIRED);
+ return ret;
+}
+
+/**
+ * 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) {
+ /* Move name pointer. */
+ tmp_probes[i].name = probes[i].name;
+ }
+
+ /* 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;
}
- modprobe[sizeof(modprobe) - 1] = '\0';
- ret = system(modprobe);
- if (ret == -1) {
- ERR("Unable to launch modprobe for module %s",
- kern_modules_control[i].name);
- } else if (kern_modules_control[i].required
- && WEXITSTATUS(ret) != 0) {
- ERR("Unable to load module %s",
- kern_modules_control[i].name);
- } else {
- DBG("Modprobe successfully %s",
- kern_modules_control[i].name);
+
+ ret = snprintf(cur_mod->name, name_len, "lttng-probe-%s", next);
+ if (ret < 0) {
+ PERROR("snprintf modprobe name");
+ ret = -ENOMEM;
+ goto error;
}
+
+ nr_probes++;
}
+ free(tmp_list);
+ return 0;
+
error:
+ free(tmp_list);
+ free_probes();
return ret;
}
*/
int modprobe_lttng_data(void)
{
- int ret = 0, i;
- char modprobe[256];
+ int ret, i;
+ char *list;
- for (i = 0; i < ARRAY_SIZE(kern_modules_list); i++) {
- ret = snprintf(modprobe, sizeof(modprobe),
- "/sbin/modprobe %s%s",
- kern_modules_list[i].required ? "" : "-q ",
- kern_modules_list[i].name);
- if (ret < 0) {
- PERROR("snprintf modprobe");
- goto error;
+ /*
+ * 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;
}
- modprobe[sizeof(modprobe) - 1] = '\0';
- ret = system(modprobe);
- if (ret == -1) {
- ERR("Unable to launch modprobe for module %s",
- kern_modules_list[i].name);
- } else if (kern_modules_list[i].required
- && WEXITSTATUS(ret) != 0) {
- ERR("Unable to load module %s",
- kern_modules_list[i].name);
- } else {
- DBG("Modprobe successfully %s",
- kern_modules_list[i].name);
+ } 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;
+ }
+ }
+
+ /*
+ * 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, LTTNG_MOD_OPTIONAL);
+ if (ret) {
+ goto error;
+ }
+ return ret;
+
error:
+ free_probes();
return ret;
}
projects / lttng-tools.git / blobdiff