diff options
Diffstat (limited to 'collectors/ebpf.plugin/ebpf_disk.c')
| -rw-r--r-- | collectors/ebpf.plugin/ebpf_disk.c | 842 |
1 files changed, 842 insertions, 0 deletions
diff --git a/collectors/ebpf.plugin/ebpf_disk.c b/collectors/ebpf.plugin/ebpf_disk.c new file mode 100644 index 000000000..6e139ec9f --- /dev/null +++ b/collectors/ebpf.plugin/ebpf_disk.c @@ -0,0 +1,842 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#include <sys/resource.h> +#include <stdlib.h> + +#include "ebpf.h" +#include "ebpf_disk.h" + +struct config disk_config = { .first_section = NULL, + .last_section = NULL, + .mutex = NETDATA_MUTEX_INITIALIZER, + .index = { .avl_tree = { .root = NULL, .compar = appconfig_section_compare }, + .rwlock = AVL_LOCK_INITIALIZER } }; + +static ebpf_local_maps_t disk_maps[] = {{.name = "tbl_disk_iocall", .internal_input = NETDATA_DISK_HISTOGRAM_LENGTH, + .user_input = 0, .type = NETDATA_EBPF_MAP_STATIC, + .map_fd = ND_EBPF_MAP_FD_NOT_INITIALIZED}, + {.name = NULL, .internal_input = 0, .user_input = 0, + .type = NETDATA_EBPF_MAP_CONTROLLER, + .map_fd = ND_EBPF_MAP_FD_NOT_INITIALIZED}}; +static avl_tree_lock disk_tree; +netdata_ebpf_disks_t *disk_list = NULL; + +char *tracepoint_block_type = { "block"} ; +char *tracepoint_block_issue = { "block_rq_issue" }; +char *tracepoint_block_rq_complete = { "block_rq_complete" }; + +static struct bpf_link **probe_links = NULL; +static struct bpf_object *objects = NULL; + +static int was_block_issue_enabled = 0; +static int was_block_rq_complete_enabled = 0; + +static char **dimensions = NULL; +static netdata_syscall_stat_t disk_aggregated_data[NETDATA_EBPF_HIST_MAX_BINS]; +static netdata_publish_syscall_t disk_publish_aggregated[NETDATA_EBPF_HIST_MAX_BINS]; + +static int read_thread_closed = 1; + +static netdata_idx_t *disk_hash_values = NULL; +static struct netdata_static_thread disk_threads = {"DISK KERNEL", + NULL, NULL, 1, NULL, + NULL, NULL }; + +ebpf_publish_disk_t *plot_disks = NULL; +pthread_mutex_t plot_mutex; + +/***************************************************************** + * + * FUNCTIONS TO MANIPULATE HARD DISKS + * + *****************************************************************/ + +/** + * Parse start + * + * Parse start address of disk + * + * @param w structure where data is stored + * @param filename variable used to store value + * + * @return It returns 0 on success and -1 otherwise + */ +static inline int ebpf_disk_parse_start(netdata_ebpf_disks_t *w, char *filename) +{ + char content[FILENAME_MAX + 1]; + int fd = open(filename, O_RDONLY, 0); + if (fd < 0) { + return -1; + } + + ssize_t file_length = read(fd, content, 4095); + if (file_length > 0) { + if (file_length > FILENAME_MAX) + file_length = FILENAME_MAX; + + content[file_length] = '\0'; + w->start = strtoul(content, NULL, 10); + } + close(fd); + + return 0; +} + +/** + * Parse uevent + * + * Parse uevent file + * + * @param w structure where data is stored + * @param filename variable used to store value + * + * @return It returns 0 on success and -1 otherwise + */ +static inline int ebpf_parse_uevent(netdata_ebpf_disks_t *w, char *filename) +{ + char content[FILENAME_MAX + 1]; + int fd = open(filename, O_RDONLY, 0); + if (fd < 0) { + return -1; + } + + ssize_t file_length = read(fd, content, FILENAME_MAX); + if (file_length > 0) { + if (file_length > FILENAME_MAX) + file_length = FILENAME_MAX; + + content[file_length] = '\0'; + + char *s = strstr(content, "PARTNAME=EFI"); + if (s) { + w->main->boot_partition = w; + w->flags |= NETDATA_DISK_HAS_EFI; + w->boot_chart = strdupz("disk_bootsector"); + } + } + close(fd); + + return 0; +} + +/** + * Parse Size + * + * @param w structure where data is stored + * @param filename variable used to store value + * + * @return It returns 0 on success and -1 otherwise + */ +static inline int ebpf_parse_size(netdata_ebpf_disks_t *w, char *filename) +{ + char content[FILENAME_MAX + 1]; + int fd = open(filename, O_RDONLY, 0); + if (fd < 0) { + return -1; + } + + ssize_t file_length = read(fd, content, FILENAME_MAX); + if (file_length > 0) { + if (file_length > FILENAME_MAX) + file_length = FILENAME_MAX; + + content[file_length] = '\0'; + w->end = w->start + strtoul(content, NULL, 10) -1; + } + close(fd); + + return 0; +} + +/** + * Read Disk information + * + * Read disk information from /sys/block + * + * @param w structure where data is stored + * @param name disk name + */ +static void ebpf_read_disk_info(netdata_ebpf_disks_t *w, char *name) +{ + static netdata_ebpf_disks_t *main_disk = NULL; + static uint32_t key = 0; + char *path = { "/sys/block" }; + char disk[NETDATA_DISK_NAME_LEN + 1]; + char filename[FILENAME_MAX + 1]; + snprintfz(disk, NETDATA_DISK_NAME_LEN, "%s", name); + size_t length = strlen(disk); + if (!length) { + return; + } + + length--; + size_t curr = length; + while (isdigit((int)disk[length])) { + disk[length--] = '\0'; + } + + // We are looking for partition information, if it is a device we will ignore it. + if (curr == length) { + main_disk = w; + key = MKDEV(w->major, w->minor); + w->bootsector_key = key; + return; + } + w->bootsector_key = key; + w->main = main_disk; + + snprintfz(filename, FILENAME_MAX, "%s/%s/%s/uevent", path, disk, name); + if (ebpf_parse_uevent(w, filename)) + return; + + snprintfz(filename, FILENAME_MAX, "%s/%s/%s/start", path, disk, name); + if (ebpf_disk_parse_start(w, filename)) + return; + + snprintfz(filename, FILENAME_MAX, "%s/%s/%s/size", path, disk, name); + ebpf_parse_size(w, filename); +} + +/** + * New encode dev + * + * New encode algorithm extracted from https://elixir.bootlin.com/linux/v5.10.8/source/include/linux/kdev_t.h#L39 + * + * @param major driver major number + * @param minor driver minor number + * + * @return + */ +static inline uint32_t netdata_new_encode_dev(uint32_t major, uint32_t minor) { + return (minor & 0xff) | (major << 8) | ((minor & ~0xff) << 12); +} + +/** + * Compare disks + * + * Compare major and minor values to add disks to tree. + * + * @param a pointer to netdata_ebpf_disks + * @param b pointer to netdata_ebpf_disks + * + * @return It returns 0 case the values are equal, 1 case a is bigger than b and -1 case a is smaller than b. +*/ +static int ebpf_compare_disks(void *a, void *b) +{ + netdata_ebpf_disks_t *ptr1 = a; + netdata_ebpf_disks_t *ptr2 = b; + + if (ptr1->dev > ptr2->dev) + return 1; + if (ptr1->dev < ptr2->dev) + return -1; + + return 0; +} + +/** + * Update listen table + * + * Update link list when it is necessary. + * + * @param name disk name + * @param major major disk identifier + * @param minor minor disk identifier + * @param current_time current timestamp + */ +static void update_disk_table(char *name, int major, int minor, time_t current_time) +{ + netdata_ebpf_disks_t find; + netdata_ebpf_disks_t *w; + size_t length; + + uint32_t dev = netdata_new_encode_dev(major, minor); + find.dev = dev; + netdata_ebpf_disks_t *ret = (netdata_ebpf_disks_t *) avl_search_lock(&disk_tree, (avl_t *)&find); + if (ret) { // Disk is already present + ret->flags |= NETDATA_DISK_IS_HERE; + ret->last_update = current_time; + return; + } + + netdata_ebpf_disks_t *update_next = disk_list; + if (likely(disk_list)) { + netdata_ebpf_disks_t *move = disk_list; + while (move) { + if (dev == move->dev) + return; + + update_next = move; + move = move->next; + } + + w = callocz(1, sizeof(netdata_ebpf_disks_t)); + length = strlen(name); + if (length >= NETDATA_DISK_NAME_LEN) + length = NETDATA_DISK_NAME_LEN; + + memcpy(w->family, name, length); + w->family[length] = '\0'; + w->major = major; + w->minor = minor; + w->dev = netdata_new_encode_dev(major, minor); + update_next->next = w; + } else { + disk_list = callocz(1, sizeof(netdata_ebpf_disks_t)); + length = strlen(name); + if (length >= NETDATA_DISK_NAME_LEN) + length = NETDATA_DISK_NAME_LEN; + + memcpy(disk_list->family, name, length); + disk_list->family[length] = '\0'; + disk_list->major = major; + disk_list->minor = minor; + disk_list->dev = netdata_new_encode_dev(major, minor); + + w = disk_list; + } + + ebpf_read_disk_info(w, name); + + netdata_ebpf_disks_t *check; + check = (netdata_ebpf_disks_t *) avl_insert_lock(&disk_tree, (avl_t *)w); + if (check != w) + error("Internal error, cannot insert the AVL tree."); + +#ifdef NETDATA_INTERNAL_CHECKS + info("The Latency is monitoring the hard disk %s (Major = %d, Minor = %d, Device = %u)", name, major, minor,w->dev); +#endif + + w->flags |= NETDATA_DISK_IS_HERE; +} + +/** + * Read Local Disks + * + * Parse /proc/partitions to get block disks used to measure latency. + * + * @return It returns 0 on success and -1 otherwise + */ +static int read_local_disks() +{ + char filename[FILENAME_MAX + 1]; + snprintfz(filename, FILENAME_MAX, "%s%s", netdata_configured_host_prefix, NETDATA_EBPF_PROC_PARTITIONS); + procfile *ff = procfile_open(filename, " \t:", PROCFILE_FLAG_DEFAULT); + if (!ff) + return -1; + + ff = procfile_readall(ff); + if (!ff) + return -1; + + size_t lines = procfile_lines(ff), l; + time_t current_time = now_realtime_sec(); + for(l = 2; l < lines ;l++) { + size_t words = procfile_linewords(ff, l); + // This is header or end of file + if (unlikely(words < 4)) + continue; + + int major = (int)strtol(procfile_lineword(ff, l, 0), NULL, 10); + // The main goal of this thread is to measure block devices, so any block device with major number + // smaller than 7 according /proc/devices is not "important". + if (major > 7) { + int minor = (int)strtol(procfile_lineword(ff, l, 1), NULL, 10); + update_disk_table(procfile_lineword(ff, l, 3), major, minor, current_time); + } + } + + procfile_close(ff); + + return 0; +} + +/** + * Update disks + * + * @param em main thread structure + */ +void ebpf_update_disks(ebpf_module_t *em) +{ + static time_t update_every = 0; + time_t curr = now_realtime_sec(); + if (curr < update_every) + return; + + update_every = curr + 5 * em->update_every; + + (void)read_local_disks(); +} + +/***************************************************************** + * + * FUNCTIONS TO CLOSE THE THREAD + * + *****************************************************************/ + +/** + * Disk disable tracepoints + * + * Disable tracepoints when the plugin was responsible to enable it. + */ +static void ebpf_disk_disable_tracepoints() +{ + char *default_message = { "Cannot disable the tracepoint" }; + if (!was_block_issue_enabled) { + if (ebpf_disable_tracing_values(tracepoint_block_type, tracepoint_block_issue)) + error("%s %s/%s.", default_message, tracepoint_block_type, tracepoint_block_issue); + } + + if (!was_block_rq_complete_enabled) { + if (ebpf_disable_tracing_values(tracepoint_block_type, tracepoint_block_rq_complete)) + error("%s %s/%s.", default_message, tracepoint_block_type, tracepoint_block_rq_complete); + } +} + +/** + * Cleanup plot disks + * + * Clean disk list + */ +static void ebpf_cleanup_plot_disks() +{ + ebpf_publish_disk_t *move = plot_disks, *next; + while (move) { + next = move->next; + + freez(move); + + move = next; + } +} + +/** + * Cleanup Disk List + */ +static void ebpf_cleanup_disk_list() +{ + netdata_ebpf_disks_t *move = disk_list; + while (move) { + netdata_ebpf_disks_t *next = move->next; + + freez(move->histogram.name); + freez(move->boot_chart); + freez(move); + + move = next; + } +} + +/** + * Clean up the main thread. + * + * @param ptr thread data. + */ +static void ebpf_disk_cleanup(void *ptr) +{ + ebpf_disk_disable_tracepoints(); + + ebpf_module_t *em = (ebpf_module_t *)ptr; + if (!em->enabled) + return; + + heartbeat_t hb; + heartbeat_init(&hb); + uint32_t tick = 2 * USEC_PER_MS; + while (!read_thread_closed) { + usec_t dt = heartbeat_next(&hb, tick); + UNUSED(dt); + } + + if (dimensions) + ebpf_histogram_dimension_cleanup(dimensions, NETDATA_EBPF_HIST_MAX_BINS); + + freez(disk_hash_values); + freez(disk_threads.thread); + pthread_mutex_destroy(&plot_mutex); + + ebpf_cleanup_plot_disks(); + ebpf_cleanup_disk_list(); + + if (probe_links) { + struct bpf_program *prog; + size_t i = 0 ; + bpf_object__for_each_program(prog, objects) { + bpf_link__destroy(probe_links[i]); + i++; + } + bpf_object__close(objects); + } +} + +/***************************************************************** + * + * MAIN LOOP + * + *****************************************************************/ + +/** + * Fill Plot list + * + * @param ptr a pointer for current disk + */ +static void ebpf_fill_plot_disks(netdata_ebpf_disks_t *ptr) +{ + pthread_mutex_lock(&plot_mutex); + ebpf_publish_disk_t *w; + if (likely(plot_disks)) { + ebpf_publish_disk_t *move = plot_disks, *store = plot_disks; + while (move) { + if (move->plot == ptr) { + pthread_mutex_unlock(&plot_mutex); + return; + } + + store = move; + move = move->next; + } + + w = callocz(1, sizeof(ebpf_publish_disk_t)); + w->plot = ptr; + store->next = w; + } else { + plot_disks = callocz(1, sizeof(ebpf_publish_disk_t)); + plot_disks->plot = ptr; + } + pthread_mutex_unlock(&plot_mutex); + + ptr->flags |= NETDATA_DISK_ADDED_TO_PLOT_LIST; +} + +/** + * Read hard disk table + * + * @param table file descriptor for table + * + * Read the table with number of calls for all functions + */ +static void read_hard_disk_tables(int table) +{ + netdata_idx_t *values = disk_hash_values; + block_key_t key = {}; + block_key_t next_key = {}; + + netdata_ebpf_disks_t *ret = NULL; + + while (bpf_map_get_next_key(table, &key, &next_key) == 0) { + int test = bpf_map_lookup_elem(table, &key, values); + if (test < 0) { + key = next_key; + continue; + } + + netdata_ebpf_disks_t find; + find.dev = key.dev; + + if (likely(ret)) { + if (find.dev != ret->dev) + ret = (netdata_ebpf_disks_t *)avl_search_lock(&disk_tree, (avl_t *)&find); + } else + ret = (netdata_ebpf_disks_t *)avl_search_lock(&disk_tree, (avl_t *)&find); + + // Disk was inserted after we parse /proc/partitions + if (!ret) { + if (read_local_disks()) { + key = next_key; + continue; + } + + ret = (netdata_ebpf_disks_t *)avl_search_lock(&disk_tree, (avl_t *)&find); + if (!ret) { + // We should never reach this point, but we are adding it to keep a safe code + key = next_key; + continue; + } + } + + uint64_t total = 0; + int i; + int end = (running_on_kernel < NETDATA_KERNEL_V4_15) ? 1 : ebpf_nprocs; + for (i = 0; i < end; i++) { + total += values[i]; + } + + ret->histogram.histogram[key.bin] = total; + + if (!(ret->flags & NETDATA_DISK_ADDED_TO_PLOT_LIST)) + ebpf_fill_plot_disks(ret); + + key = next_key; + } +} + +/** + * Disk read hash + * + * This is the thread callback. + * This thread is necessary, because we cannot freeze the whole plugin to read the data on very busy socket. + * + * @param ptr It is a NULL value for this thread. + * + * @return It always returns NULL. + */ +void *ebpf_disk_read_hash(void *ptr) +{ + heartbeat_t hb; + heartbeat_init(&hb); + + ebpf_module_t *em = (ebpf_module_t *)ptr; + + usec_t step = NETDATA_LATENCY_DISK_SLEEP_MS * em->update_every; + while (!close_ebpf_plugin) { + usec_t dt = heartbeat_next(&hb, step); + (void)dt; + + read_hard_disk_tables(disk_maps[NETDATA_DISK_READ].map_fd); + } + + return NULL; +} + +/** + * Obsolete Hard Disk charts + * + * Make Hard disk charts and fill chart name + * + * @param w the structure with necessary information to create the chart + * @param update_every value to overwrite the update frequency set by the server. + */ +static void ebpf_obsolete_hd_charts(netdata_ebpf_disks_t *w, int update_every) +{ + ebpf_write_chart_obsolete(w->histogram.name, w->family, w->histogram.title, EBPF_COMMON_DIMENSION_CALL, + w->family, NETDATA_EBPF_CHART_TYPE_STACKED, "disk.latency_io", + w->histogram.order, update_every); + + w->flags = 0; +} + +/** + * Create Hard Disk charts + * + * Make Hard disk charts and fill chart name + * + * @param w the structure with necessary information to create the chart + * @param update_every value to overwrite the update frequency set by the server. + */ +static void ebpf_create_hd_charts(netdata_ebpf_disks_t *w, int update_every) +{ + int order = NETDATA_CHART_PRIO_DISK_LATENCY; + char *family = w->family; + + w->histogram.name = strdupz("disk_latency_io"); + w->histogram.title = NULL; + w->histogram.order = order; + + ebpf_create_chart(w->histogram.name, family, "Disk latency", EBPF_COMMON_DIMENSION_CALL, + family, "disk.latency_io", NETDATA_EBPF_CHART_TYPE_STACKED, order, + ebpf_create_global_dimension, disk_publish_aggregated, NETDATA_EBPF_HIST_MAX_BINS, + update_every, NETDATA_EBPF_MODULE_NAME_DISK); + order++; + + w->flags |= NETDATA_DISK_CHART_CREATED; +} + +/** + * Remove pointer from plot + * + * Remove pointer from plot list when the disk is not present. + */ +static void ebpf_remove_pointer_from_plot_disk(ebpf_module_t *em) +{ + time_t current_time = now_realtime_sec(); + time_t limit = 10 * em->update_every; + pthread_mutex_lock(&plot_mutex); + ebpf_publish_disk_t *move = plot_disks, *prev = plot_disks; + int update_every = em->update_every; + while (move) { + netdata_ebpf_disks_t *ned = move->plot; + uint32_t flags = ned->flags; + + if (!(flags & NETDATA_DISK_IS_HERE) && ((current_time - ned->last_update) > limit)) { + ebpf_obsolete_hd_charts(ned, update_every); + avl_t *ret = (avl_t *)avl_remove_lock(&disk_tree, (avl_t *)ned); + UNUSED(ret); + if (move == plot_disks) { + freez(move); + plot_disks = NULL; + break; + } else { + prev->next = move->next; + ebpf_publish_disk_t *clean = move; + move = move->next; + freez(clean); + continue; + } + } + + prev = move; + move = move->next; + } + pthread_mutex_unlock(&plot_mutex); +} + +/** + * Send Hard disk data + * + * Send hard disk information to Netdata. + * + * @param update_every value to overwrite the update frequency set by the server. + */ +static void ebpf_latency_send_hd_data(int update_every) +{ + pthread_mutex_lock(&plot_mutex); + if (!plot_disks) { + pthread_mutex_unlock(&plot_mutex); + return; + } + + ebpf_publish_disk_t *move = plot_disks; + while (move) { + netdata_ebpf_disks_t *ned = move->plot; + uint32_t flags = ned->flags; + if (!(flags & NETDATA_DISK_CHART_CREATED)) { + ebpf_create_hd_charts(ned, update_every); + } + + if ((flags & NETDATA_DISK_CHART_CREATED)) { + write_histogram_chart(ned->histogram.name, ned->family, + ned->histogram.histogram, dimensions, NETDATA_EBPF_HIST_MAX_BINS); + } + + ned->flags &= ~NETDATA_DISK_IS_HERE; + + move = move->next; + } + pthread_mutex_unlock(&plot_mutex); +} + +/** +* Main loop for this collector. +*/ +static void disk_collector(ebpf_module_t *em) +{ + disk_hash_values = callocz(ebpf_nprocs, sizeof(netdata_idx_t)); + disk_threads.thread = mallocz(sizeof(netdata_thread_t)); + disk_threads.start_routine = ebpf_disk_read_hash; + + netdata_thread_create(disk_threads.thread, disk_threads.name, NETDATA_THREAD_OPTION_JOINABLE, + ebpf_disk_read_hash, em); + + int update_every = em->update_every; + int counter = update_every - 1; + read_thread_closed = 0; + while (!close_ebpf_plugin) { + pthread_mutex_lock(&collect_data_mutex); + pthread_cond_wait(&collect_data_cond_var, &collect_data_mutex); + + if (++counter == update_every) { + counter = 0; + pthread_mutex_lock(&lock); + ebpf_remove_pointer_from_plot_disk(em); + ebpf_latency_send_hd_data(update_every); + + pthread_mutex_unlock(&lock); + } + + pthread_mutex_unlock(&collect_data_mutex); + + ebpf_update_disks(em); + } + read_thread_closed = 1; +} + +/***************************************************************** + * + * EBPF DISK THREAD + * + *****************************************************************/ + +/** + * Enable tracepoints + * + * Enable necessary tracepoints for thread. + * + * @return It returns 0 on success and -1 otherwise + */ +static int ebpf_disk_enable_tracepoints() +{ + int test = ebpf_is_tracepoint_enabled(tracepoint_block_type, tracepoint_block_issue); + if (test == -1) + return -1; + else if (!test) { + if (ebpf_enable_tracing_values(tracepoint_block_type, tracepoint_block_issue)) + return -1; + } + was_block_issue_enabled = test; + + test = ebpf_is_tracepoint_enabled(tracepoint_block_type, tracepoint_block_rq_complete); + if (test == -1) + return -1; + else if (!test) { + if (ebpf_enable_tracing_values(tracepoint_block_type, tracepoint_block_rq_complete)) + return -1; + } + was_block_rq_complete_enabled = test; + + return 0; +} + +/** + * Disk thread + * + * Thread used to generate disk charts. + * + * @param ptr a pointer to `struct ebpf_module` + * + * @return It always return NULL + */ +void *ebpf_disk_thread(void *ptr) +{ + netdata_thread_cleanup_push(ebpf_disk_cleanup, ptr); + + ebpf_module_t *em = (ebpf_module_t *)ptr; + em->maps = disk_maps; + + if (!em->enabled) + goto enddisk; + + if (ebpf_disk_enable_tracepoints()) { + em->enabled = CONFIG_BOOLEAN_NO; + goto enddisk; + } + + avl_init_lock(&disk_tree, ebpf_compare_disks); + if (read_local_disks()) { + em->enabled = CONFIG_BOOLEAN_NO; + goto enddisk; + } + + if (pthread_mutex_init(&plot_mutex, NULL)) { + error("Cannot initialize local mutex"); + goto enddisk; + } + + probe_links = ebpf_load_program(ebpf_plugin_dir, em, kernel_string, &objects); + if (!probe_links) { + goto enddisk; + } + + int algorithms[NETDATA_EBPF_HIST_MAX_BINS]; + ebpf_fill_algorithms(algorithms, NETDATA_EBPF_HIST_MAX_BINS, NETDATA_EBPF_INCREMENTAL_IDX); + dimensions = ebpf_fill_histogram_dimension(NETDATA_EBPF_HIST_MAX_BINS); + + ebpf_global_labels(disk_aggregated_data, disk_publish_aggregated, dimensions, dimensions, algorithms, + NETDATA_EBPF_HIST_MAX_BINS); + + disk_collector(em); + +enddisk: + netdata_thread_cleanup_pop(1); + + return NULL; +} |