diff options
Diffstat (limited to 'collectors/ebpf.plugin/ebpf_dcstat.c')
| -rw-r--r-- | collectors/ebpf.plugin/ebpf_dcstat.c | 224 |
1 files changed, 216 insertions, 8 deletions
diff --git a/collectors/ebpf.plugin/ebpf_dcstat.c b/collectors/ebpf.plugin/ebpf_dcstat.c index fba87007..619d8520 100644 --- a/collectors/ebpf.plugin/ebpf_dcstat.c +++ b/collectors/ebpf.plugin/ebpf_dcstat.c @@ -49,6 +49,179 @@ static ebpf_specify_name_t dc_optional_name[] = { {.program_name = "netdata_look .retprobe = CONFIG_BOOLEAN_NO}, {.program_name = NULL}}; +netdata_ebpf_targets_t dc_targets[] = { {.name = "lookup_fast", .mode = EBPF_LOAD_TRAMPOLINE}, + {.name = "d_lookup", .mode = EBPF_LOAD_TRAMPOLINE}, + {.name = NULL, .mode = EBPF_LOAD_TRAMPOLINE}}; + +#ifdef LIBBPF_MAJOR_VERSION +#include "includes/dc.skel.h" // BTF code + +static struct dc_bpf *bpf_obj = NULL; + +/** + * Disable probe + * + * Disable all probes to use exclusively another method. + * + * @param obj is the main structure for bpf objects + */ +static inline void ebpf_dc_disable_probes(struct dc_bpf *obj) +{ + bpf_program__set_autoload(obj->progs.netdata_lookup_fast_kprobe, false); + bpf_program__set_autoload(obj->progs.netdata_d_lookup_kretprobe, false); +} + +/* + * Disable trampoline + * + * Disable all trampoline to use exclusively another method. + * + * @param obj is the main structure for bpf objects. + */ +static inline void ebpf_dc_disable_trampoline(struct dc_bpf *obj) +{ + bpf_program__set_autoload(obj->progs.netdata_lookup_fast_fentry, false); + bpf_program__set_autoload(obj->progs.netdata_d_lookup_fexit, false); +} + +/** + * Set trampoline target + * + * Set the targets we will monitor. + * + * @param obj is the main structure for bpf objects. + */ +static void ebpf_dc_set_trampoline_target(struct dc_bpf *obj) +{ + bpf_program__set_attach_target(obj->progs.netdata_lookup_fast_fentry, 0, + dc_targets[NETDATA_DC_TARGET_LOOKUP_FAST].name); + + bpf_program__set_attach_target(obj->progs.netdata_d_lookup_fexit, 0, + dc_targets[NETDATA_DC_TARGET_D_LOOKUP].name); +} + +/** + * Mount Attach Probe + * + * Attach probes to target + * + * @param obj is the main structure for bpf objects. + * + * @return It returns 0 on success and -1 otherwise. + */ +static int ebpf_dc_attach_probes(struct dc_bpf *obj) +{ + obj->links.netdata_d_lookup_kretprobe = bpf_program__attach_kprobe(obj->progs.netdata_d_lookup_kretprobe, + true, + dc_targets[NETDATA_DC_TARGET_D_LOOKUP].name); + int ret = libbpf_get_error(obj->links.netdata_d_lookup_kretprobe); + if (ret) + return -1; + + char *lookup_name = (dc_optional_name[NETDATA_DC_TARGET_LOOKUP_FAST].optional) ? + dc_optional_name[NETDATA_DC_TARGET_LOOKUP_FAST].optional : + dc_targets[NETDATA_DC_TARGET_LOOKUP_FAST].name ; + + obj->links.netdata_lookup_fast_kprobe = bpf_program__attach_kprobe(obj->progs.netdata_lookup_fast_kprobe, + false, + lookup_name); + ret = libbpf_get_error(obj->links.netdata_lookup_fast_kprobe); + if (ret) + return -1; + + return 0; +} + +/** + * Adjust Map Size + * + * Resize maps according input from users. + * + * @param obj is the main structure for bpf objects. + * @param em structure with configuration + */ +static void ebpf_dc_adjust_map_size(struct dc_bpf *obj, ebpf_module_t *em) +{ + ebpf_update_map_size(obj->maps.dcstat_pid, &dcstat_maps[NETDATA_DCSTAT_PID_STATS], + em, bpf_map__name(obj->maps.dcstat_pid)); +} + +/** + * Set hash tables + * + * Set the values for maps according the value given by kernel. + * + * @param obj is the main structure for bpf objects. + */ +static void ebpf_dc_set_hash_tables(struct dc_bpf *obj) +{ + dcstat_maps[NETDATA_DCSTAT_GLOBAL_STATS].map_fd = bpf_map__fd(obj->maps.dcstat_global); + dcstat_maps[NETDATA_DCSTAT_PID_STATS].map_fd = bpf_map__fd(obj->maps.dcstat_pid); + dcstat_maps[NETDATA_DCSTAT_CTRL].map_fd = bpf_map__fd(obj->maps.dcstat_ctrl); +} + +/** + * Update Load + * + * For directory cache, some distributions change the function name, and we do not have condition to use + * TRAMPOLINE like other functions. + * + * @param em structure with configuration + * + * @return When then symbols were not modified, it returns TRAMPOLINE, else it returns RETPROBE. + */ +netdata_ebpf_program_loaded_t ebpf_dc_update_load(ebpf_module_t *em) +{ + if (!strcmp(dc_optional_name[NETDATA_DC_TARGET_LOOKUP_FAST].optional, + dc_optional_name[NETDATA_DC_TARGET_LOOKUP_FAST].function_to_attach)) + return EBPF_LOAD_TRAMPOLINE; + + if (em->targets[NETDATA_DC_TARGET_LOOKUP_FAST].mode != EBPF_LOAD_RETPROBE) + info("When your kernel was compiled the symbol %s was modified, instead to use `trampoline`, the plugin will use `probes`.", + dc_optional_name[NETDATA_DC_TARGET_LOOKUP_FAST].function_to_attach); + + return EBPF_LOAD_RETPROBE; +} + +/** + * Load and attach + * + * Load and attach the eBPF code in kernel. + * + * @param obj is the main structure for bpf objects. + * @param em structure with configuration + * + * @return it returns 0 on succes and -1 otherwise + */ +static inline int ebpf_dc_load_and_attach(struct dc_bpf *obj, ebpf_module_t *em) +{ + netdata_ebpf_program_loaded_t test = ebpf_dc_update_load(em); + if (test == EBPF_LOAD_TRAMPOLINE) { + ebpf_dc_disable_probes(obj); + + ebpf_dc_set_trampoline_target(obj); + } else { + ebpf_dc_disable_trampoline(obj); + } + + int ret = dc_bpf__load(obj); + if (ret) { + return ret; + } + + ebpf_dc_adjust_map_size(obj, em); + + ret = (test == EBPF_LOAD_TRAMPOLINE) ? dc_bpf__attach(obj) : ebpf_dc_attach_probes(obj); + if (!ret) { + ebpf_dc_set_hash_tables(obj); + + ebpf_update_controller(dcstat_maps[NETDATA_DCSTAT_CTRL].map_fd, em); + } + + return ret; +} +#endif + /***************************************************************** * * COMMON FUNCTIONS @@ -141,6 +314,10 @@ static void ebpf_dcstat_cleanup(void *ptr) } bpf_object__close(objects); } +#ifdef LIBBPF_MAJOR_VERSION + else if (bpf_obj) + dc_bpf__destroy(bpf_obj); +#endif } /***************************************************************** @@ -937,6 +1114,38 @@ static void ebpf_dcstat_allocate_global_vectors(int apps) * *****************************************************************/ +/* + * Load BPF + * + * Load BPF files. + * + * @param em the structure with configuration + */ +static int ebpf_dcstat_load_bpf(ebpf_module_t *em) +{ + int ret = 0; + if (em->load == EBPF_LOAD_LEGACY) { + probe_links = ebpf_load_program(ebpf_plugin_dir, em, running_on_kernel, isrh, &objects); + if (!probe_links) { + ret = -1; + } + } +#ifdef LIBBPF_MAJOR_VERSION + else { + bpf_obj = dc_bpf__open(); + if (!bpf_obj) + ret = -1; + else + ret = ebpf_dc_load_and_attach(bpf_obj, em); + } +#endif + + if (ret) + error("%s %s", EBPF_DEFAULT_ERROR_MSG, em->thread_name); + + return ret; +} + /** * Directory Cache thread * @@ -960,17 +1169,16 @@ void *ebpf_dcstat_thread(void *ptr) if (!em->enabled) goto enddcstat; - ebpf_dcstat_allocate_global_vectors(em->apps_charts); - - pthread_mutex_lock(&lock); - - probe_links = ebpf_load_program(ebpf_plugin_dir, em, running_on_kernel, isrh, &objects); - if (!probe_links) { - pthread_mutex_unlock(&lock); +#ifdef LIBBPF_MAJOR_VERSION + ebpf_adjust_thread_load(em, default_btf); +#endif + if (ebpf_dcstat_load_bpf(em)) { em->enabled = CONFIG_BOOLEAN_NO; goto enddcstat; } + ebpf_dcstat_allocate_global_vectors(em->apps_charts); + int algorithms[NETDATA_DCSTAT_IDX_END] = { NETDATA_EBPF_ABSOLUTE_IDX, NETDATA_EBPF_ABSOLUTE_IDX, NETDATA_EBPF_ABSOLUTE_IDX, NETDATA_EBPF_ABSOLUTE_IDX @@ -980,9 +1188,9 @@ void *ebpf_dcstat_thread(void *ptr) dcstat_counter_dimension_name, dcstat_counter_dimension_name, algorithms, NETDATA_DCSTAT_IDX_END); + pthread_mutex_lock(&lock); ebpf_create_filesystem_charts(em->update_every); ebpf_update_stats(&plugin_statistics, em); - pthread_mutex_unlock(&lock); dcstat_collector(em); |