// SPDX-License-Identifier: GPL-3.0-or-later
#include "ebpf.h"
#include "ebpf_sync.h"
static char *sync_counter_dimension_name[NETDATA_SYNC_IDX_END] = { "sync", "syncfs", "msync", "fsync", "fdatasync",
"sync_file_range" };
static netdata_syscall_stat_t sync_counter_aggregated_data[NETDATA_SYNC_IDX_END];
static netdata_publish_syscall_t sync_counter_publish_aggregated[NETDATA_SYNC_IDX_END];
static netdata_idx_t sync_hash_values[NETDATA_SYNC_IDX_END];
struct netdata_static_thread sync_threads = {
.name = "SYNC KERNEL",
.config_section = NULL,
.config_name = NULL,
.env_name = NULL,
.enabled = 1,
.thread = NULL,
.init_routine = NULL,
.start_routine = NULL
};
static ebpf_local_maps_t sync_maps[] = {{.name = "tbl_sync", .internal_input = NETDATA_SYNC_END,
.user_input = 0, .type = NETDATA_EBPF_MAP_STATIC,
.map_fd = ND_EBPF_MAP_FD_NOT_INITIALIZED},
{.name = "tbl_syncfs", .internal_input = NETDATA_SYNC_END,
.user_input = 0, .type = NETDATA_EBPF_MAP_STATIC,
.map_fd = ND_EBPF_MAP_FD_NOT_INITIALIZED},
{.name = "tbl_msync", .internal_input = NETDATA_SYNC_END,
.user_input = 0, .type = NETDATA_EBPF_MAP_STATIC,
.map_fd = ND_EBPF_MAP_FD_NOT_INITIALIZED},
{.name = "tbl_fsync", .internal_input = NETDATA_SYNC_END,
.user_input = 0, .type = NETDATA_EBPF_MAP_STATIC,
.map_fd = ND_EBPF_MAP_FD_NOT_INITIALIZED},
{.name = "tbl_fdatasync", .internal_input = NETDATA_SYNC_END,
.user_input = 0, .type = NETDATA_EBPF_MAP_STATIC,
.map_fd = ND_EBPF_MAP_FD_NOT_INITIALIZED},
{.name = "tbl_syncfr", .internal_input = NETDATA_SYNC_END,
.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}};
struct config sync_config = { .first_section = NULL,
.last_section = NULL,
.mutex = NETDATA_MUTEX_INITIALIZER,
.index = { .avl_tree = { .root = NULL, .compar = appconfig_section_compare },
.rwlock = AVL_LOCK_INITIALIZER } };
netdata_ebpf_targets_t sync_targets[] = { {.name = NETDATA_SYSCALLS_SYNC, .mode = EBPF_LOAD_TRAMPOLINE},
{.name = NETDATA_SYSCALLS_SYNCFS, .mode = EBPF_LOAD_TRAMPOLINE},
{.name = NETDATA_SYSCALLS_MSYNC, .mode = EBPF_LOAD_TRAMPOLINE},
{.name = NETDATA_SYSCALLS_FSYNC, .mode = EBPF_LOAD_TRAMPOLINE},
{.name = NETDATA_SYSCALLS_FDATASYNC, .mode = EBPF_LOAD_TRAMPOLINE},
{.name = NETDATA_SYSCALLS_SYNC_FILE_RANGE, .mode = EBPF_LOAD_TRAMPOLINE},
{.name = NULL, .mode = EBPF_LOAD_TRAMPOLINE}};
#ifdef LIBBPF_MAJOR_VERSION
/*****************************************************************
*
* BTF FUNCTIONS
*
*****************************************************************/
/**
* Disable probe
*
* Disable kprobe to use another method.
*
* @param obj is the main structure for bpf objects.
*/
static inline void ebpf_sync_disable_probe(struct sync_bpf *obj)
{
bpf_program__set_autoload(obj->progs.netdata_sync_kprobe, false);
}
/**
* Disable tramppoline
*
* Disable trampoline to use another method.
*
* @param obj is the main structure for bpf objects.
*/
static inline void ebpf_sync_disable_trampoline(struct sync_bpf *obj)
{
bpf_program__set_autoload(obj->progs.netdata_sync_fentry, false);
}
/**
* Disable tracepoint
*
* Disable tracepoints according information given.
*
* @param obj object loaded
* @param idx Which syscall will not be disabled
*/
void ebpf_sync_disable_tracepoints(struct sync_bpf *obj, sync_syscalls_index_t idx)
{
if (idx != NETDATA_SYNC_SYNC_IDX)
bpf_program__set_autoload(obj->progs.netdata_sync_entry, false);
if (idx != NETDATA_SYNC_SYNCFS_IDX)
bpf_program__set_autoload(obj->progs.netdata_syncfs_entry, false);
if (idx != NETDATA_SYNC_MSYNC_IDX)
bpf_program__set_autoload(obj->progs.netdata_msync_entry, false);
if (idx != NETDATA_SYNC_FSYNC_IDX)
bpf_program__set_autoload(obj->progs.netdata_fsync_entry, false);
if (idx != NETDATA_SYNC_FDATASYNC_IDX)
bpf_program__set_autoload(obj->progs.netdata_fdatasync_entry, false);
if (idx != NETDATA_SYNC_SYNC_FILE_RANGE_IDX)
bpf_program__set_autoload(obj->progs.netdata_sync_file_range_entry, false);
}
/**
* Set hash tables
*
* Set the values for maps according the value given by kernel.
*
* @param obj is the main structure for bpf objects.
* @param idx the index for the main structure
*/
static void ebpf_sync_set_hash_tables(struct sync_bpf *obj, sync_syscalls_index_t idx)
{
sync_maps[idx].map_fd = bpf_map__fd(obj->maps.tbl_sync);
}
/**
* Load and attach
*
* Load and attach the eBPF code in kernel.
*
* @param obj is the main structure for bpf objects.
* @param em the structure with configuration
* @param target the syscall that we are attaching a tracer.
* @param idx the index for the main structure
*
* @return it returns 0 on succes and -1 otherwise
*/
static inline int ebpf_sync_load_and_attach(struct sync_bpf *obj, ebpf_module_t *em, char *target,
sync_syscalls_index_t idx)
{
netdata_ebpf_targets_t *synct = em->targets;
netdata_ebpf_program_loaded_t test = synct[NETDATA_SYNC_SYNC_IDX].mode;
if (test == EBPF_LOAD_TRAMPOLINE) {
ebpf_sync_disable_probe(obj);
ebpf_sync_disable_tracepoints(obj, NETDATA_SYNC_IDX_END);
bpf_program__set_attach_target(obj->progs.netdata_sync_fentry, 0,
target);
} else if (test == EBPF_LOAD_PROBE ||
test == EBPF_LOAD_RETPROBE) {
ebpf_sync_disable_tracepoints(obj, NETDATA_SYNC_IDX_END);
ebpf_sync_disable_trampoline(obj);
} else {
ebpf_sync_disable_probe(obj);
ebpf_sync_disable_trampoline(obj);
ebpf_sync_disable_tracepoints(obj, idx);
}
int ret = sync_bpf__load(obj);
if (!ret) {
if (test != EBPF_LOAD_PROBE && test != EBPF_LOAD_RETPROBE) {
ret = sync_bpf__attach(obj);
} else {
obj->links.netdata_sync_kprobe = bpf_program__attach_kprobe(obj->progs.netdata_sync_kprobe,
false, target);
ret = (int)libbpf_get_error(obj->links.netdata_sync_kprobe);
}
if (!ret)
ebpf_sync_set_hash_tables(obj, idx);
}
return ret;
}
#endif
/*****************************************************************
*
* CLEANUP THREAD
*
*****************************************************************/
#ifdef LIBBPF_MAJOR_VERSION
/**
* Cleanup Objects
*
* Cleanup loaded objects when thread was initialized.
*/
void ebpf_sync_cleanup_objects()
{
int i;
for (i = 0; local_syscalls[i].syscall; i++) {
ebpf_sync_syscalls_t *w = &local_syscalls[i];
if (w->sync_obj)
sync_bpf__destroy(w->sync_obj);
}
}
#endif
/**
* Sync Free
*
* Cleanup variables after child threads to stop
*
* @param ptr thread data.
*/
static void ebpf_sync_free(ebpf_module_t *em)
{
pthread_mutex_lock(&ebpf_exit_cleanup);
if (em->thread->enabled == NETDATA_THREAD_EBPF_RUNNING) {
em->thread->enabled = NETDATA_THREAD_EBPF_STOPPING;
pthread_mutex_unlock(&ebpf_exit_cleanup);
return;
}
pthread_mutex_unlock(&ebpf_exit_cleanup);
#ifdef LIBBPF_MAJOR_VERSION
ebpf_sync_cleanup_objects();
#endif
freez(sync_threads.thread);
pthread_mutex_lock(&ebpf_exit_cleanup);
em->thread->enabled = NETDATA_THREAD_EBPF_STOPPED;
pthread_mutex_unlock(&ebpf_exit_cleanup);
}
/**
* Exit
*
* Clean up the main thread.
*
* @param ptr thread data.
*/
static void ebpf_sync_exit(void *ptr)
{
ebpf_module_t *em = (ebpf_module_t *)ptr;
if (sync_threads.thread)
netdata_thread_cancel(*sync_threads.thread);
ebpf_sync_free(em);
}
/**
* Clean up the main thread.
*
* @param ptr thread data.
*/
static void ebpf_sync_cleanup(void *ptr)
{
ebpf_module_t *em = (ebpf_module_t *)ptr;
ebpf_sync_free(em);
}
/*****************************************************************
*
* INITIALIZE THREAD
*
*****************************************************************/
/**
* Load Legacy
*
* Load legacy code.
*
* @param w is the sync output structure with pointers to objects loaded.
* @param em is structure with configuration
*
* @return 0 on success and -1 otherwise.
*/
static int ebpf_sync_load_legacy(ebpf_sync_syscalls_t *w, ebpf_module_t *em)
{
em->thread_name = w->syscall;
if (!w->probe_links) {
w->probe_links = ebpf_load_program(ebpf_plugin_dir, em, running_on_kernel, isrh, &w->objects);
if (!w->probe_links) {
return -1;
}
}
return 0;
}
/*
* Initialize Syscalls
*
* Load the eBPF programs to monitor syscalls
*
* @return 0 on success and -1 otherwise.
*/
static int ebpf_sync_initialize_syscall(ebpf_module_t *em)
{
int i;
const char *saved_name = em->thread_name;
int errors = 0;
for (i = 0; local_syscalls[i].syscall; i++) {
ebpf_sync_syscalls_t *w = &local_syscalls[i];
if (w->enabled) {
if (em->load & EBPF_LOAD_LEGACY) {
if (ebpf_sync_load_legacy(w, em))
errors++;
em->thread_name = saved_name;
}
#ifdef LIBBPF_MAJOR_VERSION
else {
char syscall[NETDATA_EBPF_MAX_SYSCALL_LENGTH];
ebpf_select_host_prefix(syscall, NETDATA_EBPF_MAX_SYSCALL_LENGTH, w->syscall, running_on_kernel);
w->sync_obj = sync_bpf__open();
if (!w->sync_obj) {
errors++;
} else {
if (ebpf_is_function_inside_btf(default_btf, syscall)) {
if (ebpf_sync_load_and_attach(w->sync_obj, em, syscall, i)) {
errors++;
}
} else {
if (ebpf_sync_load_legacy(w, em))
errors++;
}
em->thread_name = saved_name;
}
}
#endif
}
}
em->thread_name = saved_name;
memset(sync_counter_aggregated_data, 0 , NETDATA_SYNC_IDX_END * sizeof(netdata_syscall_stat_t));
memset(sync_counter_publish_aggregated, 0 , NETDATA_SYNC_IDX_END * sizeof(netdata_publish_syscall_t));
memset(sync_hash_values, 0 , NETDATA_SYNC_IDX_END * sizeof(netdata_idx_t));
return (errors) ? -1 : 0;
}
/*****************************************************************
*
* DATA THREAD
*
*****************************************************************/
/**
* Read global table
*
* Read the table with number of calls for all functions
*/
static void read_global_table()
{
netdata_idx_t stored;
uint32_t idx = NETDATA_SYNC_CALL;
int i;
for (i = 0; local_syscalls[i].syscall; i++) {
if (local_syscalls[i].enabled) {
int fd = sync_maps[i].map_fd;
if (!bpf_map_lookup_elem(fd, &idx, &stored)) {
sync_hash_values[i] = stored;
}
}
}
}
/**
* Sync read hash
*
* This is the thread callback.
*
* @param ptr It is a NULL value for this thread.
*
* @return It always returns NULL.
*/
void *ebpf_sync_read_hash(void *ptr)
{
netdata_thread_cleanup_push(ebpf_sync_cleanup, ptr);
ebpf_module_t *em = (ebpf_module_t *)ptr;
heartbeat_t hb;
heartbeat_init(&hb);
usec_t step = NETDATA_EBPF_SYNC_SLEEP_MS * em->update_every;
while (!ebpf_exit_plugin) {
(void)heartbeat_next(&hb, step);
read_global_table();
}
netdata_thread_cleanup_pop(1);
return NULL;
}
/**
* Create Sync charts
*
* Create charts and dimensions according user input.
*
* @param id chart id
* @param idx the first index with data.
* @param end the last index with data.
*/
static void ebpf_send_sync_chart(char *id,
int idx,
int end)
{
write_begin_chart(NETDATA_EBPF_MEMORY_GROUP, id);
netdata_publish_syscall_t *move = &sync_counter_publish_aggregated[idx];
while (move && idx <= end) {
if (local_syscalls[idx].enabled)
write_chart_dimension(move->name, sync_hash_values[idx]);
move = move->next;
idx++;
}
write_end_chart();
}
/**
* Send data
*
* Send global charts to Netdata
*/
static void sync_send_data()
{
if (local_syscalls[NETDATA_SYNC_FSYNC_IDX].enabled || local_syscalls[NETDATA_SYNC_FDATASYNC_IDX].enabled) {
ebpf_send_sync_chart(NETDATA_EBPF_FILE_SYNC_CHART, NETDATA_SYNC_FSYNC_IDX, NETDATA_SYNC_FDATASYNC_IDX);
}
if (local_syscalls[NETDATA_SYNC_MSYNC_IDX].enabled)
ebpf_one_dimension_write_charts(NETDATA_EBPF_MEMORY_GROUP, NETDATA_EBPF_MSYNC_CHART,
sync_counter_publish_aggregated[NETDATA_SYNC_MSYNC_IDX].dimension,
sync_hash_values[NETDATA_SYNC_MSYNC_IDX]);
if (local_syscalls[NETDATA_SYNC_SYNC_IDX].enabled || local_syscalls[NETDATA_SYNC_SYNCFS_IDX].enabled) {
ebpf_send_sync_chart(NETDATA_EBPF_SYNC_CHART, NETDATA_SYNC_SYNC_IDX, NETDATA_SYNC_SYNCFS_IDX);
}
if (local_syscalls[NETDATA_SYNC_SYNC_FILE_RANGE_IDX].enabled)
ebpf_one_dimension_write_charts(NETDATA_EBPF_MEMORY_GROUP, NETDATA_EBPF_FILE_SEGMENT_CHART,
sync_counter_publish_aggregated[NETDATA_SYNC_SYNC_FILE_RANGE_IDX].dimension,
sync_hash_values[NETDATA_SYNC_SYNC_FILE_RANGE_IDX]);
}
/**
* Main loop for this collector.
*/
static void sync_collector(ebpf_module_t *em)
{
sync_threads.thread = mallocz(sizeof(netdata_thread_t));
sync_threads.start_routine = ebpf_sync_read_hash;
netdata_thread_create(sync_threads.thread, sync_threads.name, NETDATA_THREAD_OPTION_DEFAULT,
ebpf_sync_read_hash, em);
heartbeat_t hb;
heartbeat_init(&hb);
usec_t step = em->update_every * USEC_PER_SEC;
while (!ebpf_exit_plugin) {
(void)heartbeat_next(&hb, step);
if (ebpf_exit_plugin)
break;
pthread_mutex_lock(&lock);
sync_send_data();
pthread_mutex_unlock(&lock);
}
}
/*****************************************************************
*
* MAIN THREAD
*
*****************************************************************/
/**
* Create Sync charts
*
* Create charts and dimensions according user input.
*
* @param id chart id
* @param title chart title
* @param order order number of the specified chart
* @param idx the first index with data.
* @param end the last index with data.
* @param update_every value to overwrite the update frequency set by the server.
*/
static void ebpf_create_sync_chart(char *id,
char *title,
int order,
int idx,
int end,
int update_every)
{
ebpf_write_chart_cmd(NETDATA_EBPF_MEMORY_GROUP, id, title, EBPF_COMMON_DIMENSION_CALL,
NETDATA_EBPF_SYNC_SUBMENU, NETDATA_EBPF_CHART_TYPE_LINE, NULL, order,
update_every,
NETDATA_EBPF_MODULE_NAME_SYNC);
netdata_publish_syscall_t *move = &sync_counter_publish_aggregated[idx];
while (move && idx <= end) {
if (local_syscalls[idx].enabled)
ebpf_write_global_dimension(move->name, move->dimension, move->algorithm);
move = move->next;
idx++;
}
}
/**
* Create global charts
*
* Call ebpf_create_chart to create the charts for the collector.
*
* @param update_every value to overwrite the update frequency set by the server.
*/
static void ebpf_create_sync_charts(int update_every)
{
if (local_syscalls[NETDATA_SYNC_FSYNC_IDX].enabled || local_syscalls[NETDATA_SYNC_FDATASYNC_IDX].enabled)
ebpf_create_sync_chart(NETDATA_EBPF_FILE_SYNC_CHART,
"Monitor calls for fsync(2)
and fdatasync(2)
.", 21300,
NETDATA_SYNC_FSYNC_IDX, NETDATA_SYNC_FDATASYNC_IDX, update_every);
if (local_syscalls[NETDATA_SYNC_MSYNC_IDX].enabled)
ebpf_create_sync_chart(NETDATA_EBPF_MSYNC_CHART,
"Monitor calls for msync(2)
.", 21301,
NETDATA_SYNC_MSYNC_IDX, NETDATA_SYNC_MSYNC_IDX, update_every);
if (local_syscalls[NETDATA_SYNC_SYNC_IDX].enabled || local_syscalls[NETDATA_SYNC_SYNCFS_IDX].enabled)
ebpf_create_sync_chart(NETDATA_EBPF_SYNC_CHART,
"Monitor calls for sync(2)
and syncfs(2)
.", 21302,
NETDATA_SYNC_SYNC_IDX, NETDATA_SYNC_SYNCFS_IDX, update_every);
if (local_syscalls[NETDATA_SYNC_SYNC_FILE_RANGE_IDX].enabled)
ebpf_create_sync_chart(NETDATA_EBPF_FILE_SEGMENT_CHART,
"Monitor calls for sync_file_range(2)
.", 21303,
NETDATA_SYNC_SYNC_FILE_RANGE_IDX, NETDATA_SYNC_SYNC_FILE_RANGE_IDX, update_every);
}
/**
* Parse Syscalls
*
* Parse syscall options available inside ebpf.d/sync.conf
*/
static void ebpf_sync_parse_syscalls()
{
int i;
for (i = 0; local_syscalls[i].syscall; i++) {
local_syscalls[i].enabled = appconfig_get_boolean(&sync_config, NETDATA_SYNC_CONFIG_NAME,
local_syscalls[i].syscall, CONFIG_BOOLEAN_YES);
}
}
/**
* Sync thread
*
* Thread used to make sync thread
*
* @param ptr a pointer to `struct ebpf_module`
*
* @return It always return NULL
*/
void *ebpf_sync_thread(void *ptr)
{
netdata_thread_cleanup_push(ebpf_sync_exit, ptr);
ebpf_module_t *em = (ebpf_module_t *)ptr;
em->maps = sync_maps;
ebpf_sync_parse_syscalls();
#ifdef LIBBPF_MAJOR_VERSION
ebpf_adjust_thread_load(em, default_btf);
#endif
if (ebpf_sync_initialize_syscall(em)) {
em->thread->enabled = NETDATA_THREAD_EBPF_STOPPED;
goto endsync;
}
int algorithms[NETDATA_SYNC_IDX_END] = { NETDATA_EBPF_INCREMENTAL_IDX, NETDATA_EBPF_INCREMENTAL_IDX,
NETDATA_EBPF_INCREMENTAL_IDX, NETDATA_EBPF_INCREMENTAL_IDX,
NETDATA_EBPF_INCREMENTAL_IDX, NETDATA_EBPF_INCREMENTAL_IDX };
ebpf_global_labels(sync_counter_aggregated_data, sync_counter_publish_aggregated,
sync_counter_dimension_name, sync_counter_dimension_name,
algorithms, NETDATA_SYNC_IDX_END);
pthread_mutex_lock(&lock);
ebpf_create_sync_charts(em->update_every);
ebpf_update_stats(&plugin_statistics, em);
pthread_mutex_unlock(&lock);
sync_collector(em);
endsync:
ebpf_update_disabled_plugin_stats(em);
netdata_thread_cleanup_pop(1);
return NULL;
}