2 * Copyright (C) 2011 - David Goulet <dgoulet@efficios.com>
3 * 2014 - Jan Glauber <jan.glauber@gmail.com>
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.
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.
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.
22 * @brief modprobe related functions.
32 #include <common/common.h>
33 #include <common/utils.h>
36 #include "kern-modules.h"
38 #define LTTNG_MOD_REQUIRED 1
39 #define LTTNG_MOD_OPTIONAL 0
41 /* LTTng kernel tracer mandatory core modules list */
42 struct kern_modules_param kern_modules_control_core
[] = {
43 { "lttng-ring-buffer-client-discard" },
44 { "lttng-ring-buffer-client-overwrite" },
45 { "lttng-ring-buffer-metadata-client" },
46 { "lttng-ring-buffer-client-mmap-discard" },
47 { "lttng-ring-buffer-client-mmap-overwrite" },
48 { "lttng-ring-buffer-metadata-mmap-client" },
51 /* LTTng kernel tracer probe modules list */
52 struct kern_modules_param kern_modules_probes_default
[] = {
53 { "lttng-probe-asoc" },
54 { "lttng-probe-block" },
55 { "lttng-probe-btrfs" },
56 { "lttng-probe-compaction" },
57 { "lttng-probe-ext3" },
58 { "lttng-probe-ext4" },
59 { "lttng-probe-gpio" },
60 { "lttng-probe-irq" },
61 { "lttng-probe-jbd" },
62 { "lttng-probe-jbd2" },
63 { "lttng-probe-kmem" },
64 { "lttng-probe-kvm" },
65 { "lttng-probe-kvm-x86" },
66 { "lttng-probe-kvm-x86-mmu" },
67 { "lttng-probe-lock" },
68 { "lttng-probe-module" },
69 { "lttng-probe-napi" },
70 { "lttng-probe-net" },
71 { "lttng-probe-power" },
72 { "lttng-probe-printk" },
73 { "lttng-probe-random" },
74 { "lttng-probe-rcu" },
75 { "lttng-probe-regmap" },
76 { "lttng-probe-regulator" },
77 { "lttng-probe-rpm" },
78 { "lttng-probe-sched" },
79 { "lttng-probe-scsi" },
80 { "lttng-probe-signal" },
81 { "lttng-probe-skb" },
82 { "lttng-probe-sock" },
83 { "lttng-probe-statedump" },
84 { "lttng-probe-sunrpc" },
85 { "lttng-probe-timer" },
86 { "lttng-probe-udp" },
87 { "lttng-probe-vmscan" },
88 { "lttng-probe-v4l2" },
89 { "lttng-probe-workqueue" },
90 { "lttng-probe-writeback" },
91 { "lttng-probe-x86-irq-vectors" },
92 { "lttng-probe-x86-exceptions" },
95 /* dynamic probe modules list */
96 static struct kern_modules_param
*probes
;
98 static int probes_capacity
;
104 * @brief Logging function for libkmod integration.
106 static void log_kmod(void *data
, int priority
, const char *file
, int line
,
107 const char *fn
, const char *format
, va_list args
)
111 if (vasprintf(&str
, format
, args
) < 0) {
115 DBG("libkmod: %s", str
);
120 * @brief Setup the libkmod context.
122 * Create the context, add a custom logging function and preload the
123 * ressources for faster operation.
125 * @returns \c 0 on success
128 static int setup_kmod_ctx(struct kmod_ctx
**ctx
)
132 *ctx
= kmod_new(NULL
, NULL
);
134 PERROR("Unable to create kmod library context");
139 kmod_set_log_fn(*ctx
, log_kmod
, NULL
);
140 ret
= kmod_load_resources(*ctx
);
142 ERR("Failed to load kmod library resources");
151 * @brief Loads the kernel modules in \p modules
153 * @param modules List of modules to load
154 * @param entries Number of modules in the list
155 * @param required Are the modules required or optionnal
157 * If the modules are required, we will return with error after the
158 * first failed module load, otherwise we continue loading.
160 * @returns \c 0 on success
163 static int modprobe_lttng(struct kern_modules_param
*modules
,
164 int entries
, int required
)
167 struct kmod_ctx
*ctx
;
169 ret
= setup_kmod_ctx(&ctx
);
174 for (i
= 0; i
< entries
; i
++) {
175 struct kmod_module
*mod
= NULL
;
177 ret
= kmod_module_new_from_name(ctx
, modules
[i
].name
, &mod
);
179 PERROR("Failed to create kmod module for %s", modules
[i
].name
);
183 ret
= kmod_module_probe_insert_module(mod
, 0,
184 NULL
, NULL
, NULL
, NULL
);
185 if (ret
== -EEXIST
) {
186 DBG("Module %s is already loaded", modules
[i
].name
);
188 } else if (ret
< 0) {
190 ERR("Unable to load required module %s",
194 DBG("Unable to load optional module %s; continuing",
199 DBG("Modprobe successfully %s", modules
[i
].name
);
200 modules
[i
].loaded
= true;
203 kmod_module_unref(mod
);
214 * @brief Recursively unload modules.
216 * This function implements the same modules unloading behavior as
217 * 'modprobe -r' or rmmod, it will recursevily go trought the \p module
218 * dependencies and unload modules with a refcount of 0.
220 * @param mod The module to unload
222 * @returns \c 0 on success
225 static int rmmod_recurse(struct kmod_module
*mod
) {
227 struct kmod_list
*deps
, *itr
;
229 if (kmod_module_get_initstate(mod
) == KMOD_MODULE_BUILTIN
) {
230 DBG("Module %s is builtin", kmod_module_get_name(mod
));
234 ret
= kmod_module_remove_module(mod
, 0);
236 deps
= kmod_module_get_dependencies(mod
);
238 kmod_list_foreach(itr
, deps
) {
239 struct kmod_module
*dep
= kmod_module_get_module(itr
);
240 if (kmod_module_get_refcnt(dep
) == 0) {
241 DBG("Recursive remove module %s",
242 kmod_module_get_name(dep
));
245 kmod_module_unref(dep
);
247 kmod_module_unref_list(deps
);
254 * @brief Unloads the kernel modules in \p modules
256 * @param modules List of modules to unload
257 * @param entries Number of modules in the list
258 * @param required Are the modules required or optionnal
261 static void modprobe_remove_lttng(const struct kern_modules_param
*modules
,
262 int entries
, int required
)
265 struct kmod_ctx
*ctx
;
267 ret
= setup_kmod_ctx(&ctx
);
272 for (i
= entries
- 1; i
>= 0; i
--) {
273 struct kmod_module
*mod
= NULL
;
275 if (!modules
[i
].loaded
) {
279 ret
= kmod_module_new_from_name(ctx
, modules
[i
].name
, &mod
);
281 PERROR("Failed to create kmod module for %s", modules
[i
].name
);
285 ret
= rmmod_recurse(mod
);
286 if (ret
== -EEXIST
) {
287 DBG("Module %s is not in kernel.", modules
[i
].name
);
288 } else if (required
&& ret
< 0) {
289 ERR("Unable to remove module %s", modules
[i
].name
);
291 DBG("Modprobe removal successful %s",
295 kmod_module_unref(mod
);
304 #else /* HAVE_KMOD */
306 static int modprobe_lttng(struct kern_modules_param
*modules
,
307 int entries
, int required
)
312 for (i
= 0; i
< entries
; i
++) {
313 ret
= snprintf(modprobe
, sizeof(modprobe
),
314 "/sbin/modprobe %s%s",
315 required
? "" : "-q ",
318 PERROR("snprintf modprobe");
321 modprobe
[sizeof(modprobe
) - 1] = '\0';
322 ret
= system(modprobe
);
325 ERR("Unable to launch modprobe for required module %s",
329 DBG("Unable to launch modprobe for optional module %s; continuing",
333 } else if (WEXITSTATUS(ret
) != 0) {
335 ERR("Unable to load required module %s",
339 DBG("Unable to load optional module %s; continuing",
344 DBG("Modprobe successfully %s", modules
[i
].name
);
345 modules
[i
].loaded
= true;
353 static void modprobe_remove_lttng(const struct kern_modules_param
*modules
,
354 int entries
, int required
)
359 for (i
= entries
- 1; i
>= 0; i
--) {
360 if (!modules
[i
].loaded
) {
363 ret
= snprintf(modprobe
, sizeof(modprobe
),
364 "/sbin/modprobe -r -q %s",
367 PERROR("snprintf modprobe -r");
370 modprobe
[sizeof(modprobe
) - 1] = '\0';
371 ret
= system(modprobe
);
373 ERR("Unable to launch modprobe -r for module %s",
375 } else if (required
&& WEXITSTATUS(ret
) != 0) {
376 ERR("Unable to remove module %s",
379 DBG("Modprobe removal successful %s",
385 #endif /* HAVE_KMOD */
388 * Remove control kernel module(s) in reverse load order.
390 void modprobe_remove_lttng_control(void)
392 modprobe_remove_lttng(kern_modules_control_core
,
393 ARRAY_SIZE(kern_modules_control_core
),
397 static void free_probes(void)
404 for (i
= 0; i
< nr_probes
; ++i
) {
405 free(probes
[i
].name
);
413 * Remove data kernel modules in reverse load order.
415 void modprobe_remove_lttng_data(void)
420 modprobe_remove_lttng(probes
, nr_probes
, LTTNG_MOD_OPTIONAL
);
425 * Remove all kernel modules in reverse order.
427 void modprobe_remove_lttng_all(void)
429 modprobe_remove_lttng_data();
430 modprobe_remove_lttng_control();
434 * Load control kernel module(s).
436 int modprobe_lttng_control(void)
440 ret
= modprobe_lttng(kern_modules_control_core
,
441 ARRAY_SIZE(kern_modules_control_core
),
447 * Grow global list of probes (double capacity or set it to 1 if
448 * currently 0 and copy existing data).
450 static int grow_probes(void)
453 struct kern_modules_param
*tmp_probes
;
455 /* Initialize capacity to 1 if 0. */
456 if (probes_capacity
== 0) {
457 probes
= zmalloc(sizeof(*probes
));
459 PERROR("malloc probe list");
468 probes_capacity
*= 2;
470 tmp_probes
= zmalloc(sizeof(*tmp_probes
) * probes_capacity
);
472 PERROR("malloc probe list");
476 for (i
= 0; i
< nr_probes
; ++i
) {
477 /* Move name pointer. */
478 tmp_probes
[i
].name
= probes
[i
].name
;
481 /* Replace probes with larger copy. */
489 * Appends a comma-separated list of probes to the global list
492 static int append_list_to_probes(const char *list
)
496 char *tmp_list
, *cur_list
;
500 cur_list
= tmp_list
= strdup(list
);
502 PERROR("strdup temp list");
508 struct kern_modules_param
*cur_mod
;
510 next
= strtok(cur_list
, ",");
516 /* filter leading spaces */
517 while (*next
== ' ') {
521 if (probes_capacity
<= nr_probes
) {
528 /* Length 13 is "lttng-probe-" + \0 */
529 name_len
= strlen(next
) + 13;
531 cur_mod
= &probes
[nr_probes
];
532 cur_mod
->name
= zmalloc(name_len
);
533 if (!cur_mod
->name
) {
534 PERROR("malloc probe list");
539 ret
= snprintf(cur_mod
->name
, name_len
, "lttng-probe-%s", next
);
541 PERROR("snprintf modprobe name");
559 * Load data kernel module(s).
561 int modprobe_lttng_data(void)
567 * Base probes: either from command line option, environment
568 * variable or default list.
570 if (kmod_probes_list
) {
571 list
= kmod_probes_list
;
573 list
= utils_get_kmod_probes_list();
577 /* User-specified probes. */
578 ret
= append_list_to_probes(list
);
583 /* Default probes. */
584 int def_len
= ARRAY_SIZE(kern_modules_probes_default
);
586 probes
= zmalloc(sizeof(*probes
) * def_len
);
588 PERROR("malloc probe list");
592 nr_probes
= probes_capacity
= def_len
;
594 for (i
= 0; i
< def_len
; ++i
) {
595 char* name
= strdup(kern_modules_probes_default
[i
].name
);
598 PERROR("strdup probe item");
603 probes
[i
].name
= name
;
608 * Extra modules? Append them to current probes list.
610 if (kmod_extra_probes_list
) {
611 list
= kmod_extra_probes_list
;
613 list
= utils_get_extra_kmod_probes_list();
617 ret
= append_list_to_probes(list
);
624 * Load probes modules now.
626 ret
= modprobe_lttng(probes
, nr_probes
, LTTNG_MOD_OPTIONAL
);