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-rw-r--r--collectors/ebpf.plugin/ebpf_cachestat.c1335
1 files changed, 1335 insertions, 0 deletions
diff --git a/collectors/ebpf.plugin/ebpf_cachestat.c b/collectors/ebpf.plugin/ebpf_cachestat.c
new file mode 100644
index 0000000..4c41064
--- /dev/null
+++ b/collectors/ebpf.plugin/ebpf_cachestat.c
@@ -0,0 +1,1335 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "ebpf.h"
+#include "ebpf_cachestat.h"
+
+netdata_publish_cachestat_t **cachestat_pid;
+
+static char *cachestat_counter_dimension_name[NETDATA_CACHESTAT_END] = { "ratio", "dirty", "hit",
+ "miss" };
+static netdata_syscall_stat_t cachestat_counter_aggregated_data[NETDATA_CACHESTAT_END];
+static netdata_publish_syscall_t cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_END];
+
+netdata_cachestat_pid_t *cachestat_vector = NULL;
+
+static netdata_idx_t cachestat_hash_values[NETDATA_CACHESTAT_END];
+static netdata_idx_t *cachestat_values = NULL;
+
+struct netdata_static_thread cachestat_threads = {.name = "CACHESTAT KERNEL",
+ .config_section = NULL,
+ .config_name = NULL,
+ .env_name = NULL,
+ .enabled = 1,
+ .thread = NULL,
+ .init_routine = NULL,
+ .start_routine = NULL};
+
+ebpf_local_maps_t cachestat_maps[] = {{.name = "cstat_global", .internal_input = NETDATA_CACHESTAT_END,
+ .user_input = 0, .type = NETDATA_EBPF_MAP_STATIC,
+ .map_fd = ND_EBPF_MAP_FD_NOT_INITIALIZED},
+ {.name = "cstat_pid", .internal_input = ND_EBPF_DEFAULT_PID_SIZE,
+ .user_input = 0,
+ .type = NETDATA_EBPF_MAP_RESIZABLE | NETDATA_EBPF_MAP_PID,
+ .map_fd = ND_EBPF_MAP_FD_NOT_INITIALIZED},
+ {.name = "cstat_ctrl", .internal_input = NETDATA_CONTROLLER_END,
+ .user_input = 0,
+ .type = NETDATA_EBPF_MAP_CONTROLLER,
+ .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 cachestat_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 cachestat_targets[] = { {.name = "add_to_page_cache_lru", .mode = EBPF_LOAD_TRAMPOLINE},
+ {.name = "mark_page_accessed", .mode = EBPF_LOAD_TRAMPOLINE},
+ {.name = NULL, .mode = EBPF_LOAD_TRAMPOLINE},
+ {.name = "mark_buffer_dirty", .mode = EBPF_LOAD_TRAMPOLINE},
+ {.name = NULL, .mode = EBPF_LOAD_TRAMPOLINE}};
+
+#ifdef LIBBPF_MAJOR_VERSION
+#include "includes/cachestat.skel.h" // BTF code
+
+static struct cachestat_bpf *bpf_obj = NULL;
+
+/**
+ * Disable probe
+ *
+ * Disable all probes to use exclusively another method.
+ *
+ * @param obj is the main structure for bpf objects
+ */
+static void ebpf_cachestat_disable_probe(struct cachestat_bpf *obj)
+{
+ bpf_program__set_autoload(obj->progs.netdata_add_to_page_cache_lru_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_mark_page_accessed_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_folio_mark_dirty_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_set_page_dirty_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_account_page_dirtied_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_mark_buffer_dirty_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_release_task_kprobe, false);
+}
+
+/*
+ * Disable specific probe
+ *
+ * Disable probes according the kernel version
+ *
+ * @param obj is the main structure for bpf objects
+ */
+static void ebpf_cachestat_disable_specific_probe(struct cachestat_bpf *obj)
+{
+ if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_16) {
+ bpf_program__set_autoload(obj->progs.netdata_account_page_dirtied_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_set_page_dirty_kprobe, false);
+ } else if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_15) {
+ bpf_program__set_autoload(obj->progs.netdata_folio_mark_dirty_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_account_page_dirtied_kprobe, false);
+ } else {
+ bpf_program__set_autoload(obj->progs.netdata_folio_mark_dirty_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_set_page_dirty_kprobe, false);
+ }
+}
+
+/*
+ * Disable trampoline
+ *
+ * Disable all trampoline to use exclusively another method.
+ *
+ * @param obj is the main structure for bpf objects.
+ */
+static void ebpf_cachestat_disable_trampoline(struct cachestat_bpf *obj)
+{
+ bpf_program__set_autoload(obj->progs.netdata_add_to_page_cache_lru_fentry, false);
+ bpf_program__set_autoload(obj->progs.netdata_mark_page_accessed_fentry, false);
+ bpf_program__set_autoload(obj->progs.netdata_folio_mark_dirty_fentry, false);
+ bpf_program__set_autoload(obj->progs.netdata_set_page_dirty_fentry, false);
+ bpf_program__set_autoload(obj->progs.netdata_account_page_dirtied_fentry, false);
+ bpf_program__set_autoload(obj->progs.netdata_mark_buffer_dirty_fentry, false);
+ bpf_program__set_autoload(obj->progs.netdata_release_task_fentry, false);
+}
+
+/*
+ * Disable specific trampoline
+ *
+ * Disable trampoline according to kernel version.
+ *
+ * @param obj is the main structure for bpf objects.
+ */
+static void ebpf_cachestat_disable_specific_trampoline(struct cachestat_bpf *obj)
+{
+ if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_16) {
+ bpf_program__set_autoload(obj->progs.netdata_account_page_dirtied_fentry, false);
+ bpf_program__set_autoload(obj->progs.netdata_set_page_dirty_fentry, false);
+ } else if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_15) {
+ bpf_program__set_autoload(obj->progs.netdata_folio_mark_dirty_fentry, false);
+ bpf_program__set_autoload(obj->progs.netdata_account_page_dirtied_fentry, false);
+ } else {
+ bpf_program__set_autoload(obj->progs.netdata_folio_mark_dirty_fentry, false);
+ bpf_program__set_autoload(obj->progs.netdata_set_page_dirty_fentry, false);
+ }
+}
+
+/**
+ * Set trampoline target
+ *
+ * Set the targets we will monitor.
+ *
+ * @param obj is the main structure for bpf objects.
+ */
+static inline void netdata_set_trampoline_target(struct cachestat_bpf *obj)
+{
+ bpf_program__set_attach_target(obj->progs.netdata_add_to_page_cache_lru_fentry, 0,
+ cachestat_targets[NETDATA_KEY_CALLS_ADD_TO_PAGE_CACHE_LRU].name);
+
+ bpf_program__set_attach_target(obj->progs.netdata_mark_page_accessed_fentry, 0,
+ cachestat_targets[NETDATA_KEY_CALLS_MARK_PAGE_ACCESSED].name);
+
+ if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_16) {
+ bpf_program__set_attach_target(obj->progs.netdata_folio_mark_dirty_fentry, 0,
+ cachestat_targets[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED].name);
+ } else if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_15) {
+ bpf_program__set_attach_target(obj->progs.netdata_set_page_dirty_fentry, 0,
+ cachestat_targets[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED].name);
+ } else {
+ bpf_program__set_attach_target(obj->progs.netdata_account_page_dirtied_fentry, 0,
+ cachestat_targets[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED].name);
+ }
+
+ bpf_program__set_attach_target(obj->progs.netdata_mark_buffer_dirty_fentry, 0,
+ cachestat_targets[NETDATA_KEY_CALLS_MARK_BUFFER_DIRTY].name);
+
+ bpf_program__set_attach_target(obj->progs.netdata_release_task_fentry, 0,
+ EBPF_COMMON_FNCT_CLEAN_UP);
+}
+
+/**
+ * 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_cachestat_attach_probe(struct cachestat_bpf *obj)
+{
+ obj->links.netdata_add_to_page_cache_lru_kprobe = bpf_program__attach_kprobe(obj->progs.netdata_add_to_page_cache_lru_kprobe,
+ false,
+ cachestat_targets[NETDATA_KEY_CALLS_ADD_TO_PAGE_CACHE_LRU].name);
+ int ret = libbpf_get_error(obj->links.netdata_add_to_page_cache_lru_kprobe);
+ if (ret)
+ return -1;
+
+ obj->links.netdata_mark_page_accessed_kprobe = bpf_program__attach_kprobe(obj->progs.netdata_mark_page_accessed_kprobe,
+ false,
+ cachestat_targets[NETDATA_KEY_CALLS_MARK_PAGE_ACCESSED].name);
+ ret = libbpf_get_error(obj->links.netdata_mark_page_accessed_kprobe);
+ if (ret)
+ return -1;
+
+ if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_16) {
+ obj->links.netdata_folio_mark_dirty_kprobe = bpf_program__attach_kprobe(obj->progs.netdata_folio_mark_dirty_kprobe,
+ false,
+ cachestat_targets[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED].name);
+ ret = libbpf_get_error(obj->links.netdata_folio_mark_dirty_kprobe);
+ } else if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_15) {
+ obj->links.netdata_set_page_dirty_kprobe = bpf_program__attach_kprobe(obj->progs.netdata_set_page_dirty_kprobe,
+ false,
+ cachestat_targets[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED].name);
+ ret = libbpf_get_error(obj->links.netdata_set_page_dirty_kprobe);
+ } else {
+ obj->links.netdata_account_page_dirtied_kprobe = bpf_program__attach_kprobe(obj->progs.netdata_account_page_dirtied_kprobe,
+ false,
+ cachestat_targets[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED].name);
+ ret = libbpf_get_error(obj->links.netdata_account_page_dirtied_kprobe);
+ }
+
+ if (ret)
+ return -1;
+
+ obj->links.netdata_mark_buffer_dirty_kprobe = bpf_program__attach_kprobe(obj->progs.netdata_mark_buffer_dirty_kprobe,
+ false,
+ cachestat_targets[NETDATA_KEY_CALLS_MARK_BUFFER_DIRTY].name);
+ ret = libbpf_get_error(obj->links.netdata_mark_buffer_dirty_kprobe);
+ if (ret)
+ return -1;
+
+ obj->links.netdata_release_task_kprobe = bpf_program__attach_kprobe(obj->progs.netdata_release_task_kprobe,
+ false,
+ EBPF_COMMON_FNCT_CLEAN_UP);
+ ret = libbpf_get_error(obj->links.netdata_release_task_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_cachestat_adjust_map_size(struct cachestat_bpf *obj, ebpf_module_t *em)
+{
+ ebpf_update_map_size(obj->maps.cstat_pid, &cachestat_maps[NETDATA_CACHESTAT_PID_STATS],
+ em, bpf_map__name(obj->maps.cstat_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_cachestat_set_hash_tables(struct cachestat_bpf *obj)
+{
+ cachestat_maps[NETDATA_CACHESTAT_GLOBAL_STATS].map_fd = bpf_map__fd(obj->maps.cstat_global);
+ cachestat_maps[NETDATA_CACHESTAT_PID_STATS].map_fd = bpf_map__fd(obj->maps.cstat_pid);
+ cachestat_maps[NETDATA_CACHESTAT_CTRL].map_fd = bpf_map__fd(obj->maps.cstat_ctrl);
+}
+
+/**
+ * Disable Release Task
+ *
+ * Disable release task when apps is not enabled.
+ *
+ * @param obj is the main structure for bpf objects.
+ */
+static void ebpf_cachestat_disable_release_task(struct cachestat_bpf *obj)
+{
+ bpf_program__set_autoload(obj->progs.netdata_release_task_kprobe, false);
+ bpf_program__set_autoload(obj->progs.netdata_release_task_fentry, false);
+}
+
+/**
+ * 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_cachestat_load_and_attach(struct cachestat_bpf *obj, ebpf_module_t *em)
+{
+ netdata_ebpf_targets_t *mt = em->targets;
+ netdata_ebpf_program_loaded_t test = mt[NETDATA_KEY_CALLS_ADD_TO_PAGE_CACHE_LRU].mode;
+
+ if (test == EBPF_LOAD_TRAMPOLINE) {
+ ebpf_cachestat_disable_probe(obj);
+ ebpf_cachestat_disable_specific_trampoline(obj);
+
+ netdata_set_trampoline_target(obj);
+ } else {
+ ebpf_cachestat_disable_trampoline(obj);
+ ebpf_cachestat_disable_specific_probe(obj);
+ }
+
+ ebpf_cachestat_adjust_map_size(obj, em);
+
+ if (!em->apps_charts && !em->cgroup_charts)
+ ebpf_cachestat_disable_release_task(obj);
+
+ int ret = cachestat_bpf__load(obj);
+ if (ret) {
+ return ret;
+ }
+
+ ret = (test == EBPF_LOAD_TRAMPOLINE) ? cachestat_bpf__attach(obj) : ebpf_cachestat_attach_probe(obj);
+ if (!ret) {
+ ebpf_cachestat_set_hash_tables(obj);
+
+ ebpf_update_controller(cachestat_maps[NETDATA_CACHESTAT_CTRL].map_fd, em);
+ }
+
+ return ret;
+}
+#endif
+/*****************************************************************
+ *
+ * FUNCTIONS TO CLOSE THE THREAD
+ *
+ *****************************************************************/
+
+/**
+ * Cachestat Free
+ *
+ * Cleanup variables after child threads to stop
+ *
+ * @param ptr thread data.
+ */
+static void ebpf_cachestat_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);
+
+ ebpf_cleanup_publish_syscall(cachestat_counter_publish_aggregated);
+
+ freez(cachestat_vector);
+ freez(cachestat_values);
+ freez(cachestat_threads.thread);
+
+#ifdef LIBBPF_MAJOR_VERSION
+ if (bpf_obj)
+ cachestat_bpf__destroy(bpf_obj);
+#endif
+ pthread_mutex_lock(&ebpf_exit_cleanup);
+ em->thread->enabled = NETDATA_THREAD_EBPF_STOPPED;
+ pthread_mutex_unlock(&ebpf_exit_cleanup);
+}
+
+/**
+ * Cachestat exit.
+ *
+ * Cancel child and exit.
+ *
+ * @param ptr thread data.
+ */
+static void ebpf_cachestat_exit(void *ptr)
+{
+ ebpf_module_t *em = (ebpf_module_t *)ptr;
+ netdata_thread_cancel(*cachestat_threads.thread);
+ ebpf_cachestat_free(em);
+}
+
+/**
+ * Cachestat cleanup
+ *
+ * Clean up allocated addresses.
+ *
+ * @param ptr thread data.
+ */
+static void ebpf_cachestat_cleanup(void *ptr)
+{
+ ebpf_module_t *em = (ebpf_module_t *)ptr;
+ ebpf_cachestat_free(em);
+}
+
+/*****************************************************************
+ *
+ * COMMON FUNCTIONS
+ *
+ *****************************************************************/
+
+/**
+ * Update publish
+ *
+ * Update publish values before to write dimension.
+ *
+ * @param out structure that will receive data.
+ * @param mpa calls for mark_page_accessed during the last second.
+ * @param mbd calls for mark_buffer_dirty during the last second.
+ * @param apcl calls for add_to_page_cache_lru during the last second.
+ * @param apd calls for account_page_dirtied during the last second.
+ */
+void cachestat_update_publish(netdata_publish_cachestat_t *out, uint64_t mpa, uint64_t mbd,
+ uint64_t apcl, uint64_t apd)
+{
+ // Adapted algorithm from https://github.com/iovisor/bcc/blob/master/tools/cachestat.py#L126-L138
+ NETDATA_DOUBLE total = (NETDATA_DOUBLE) (((long long)mpa) - ((long long)mbd));
+ if (total < 0)
+ total = 0;
+
+ NETDATA_DOUBLE misses = (NETDATA_DOUBLE) ( ((long long) apcl) - ((long long) apd) );
+ if (misses < 0)
+ misses = 0;
+
+ // If hits are < 0, then its possible misses are overestimate due to possibly page cache read ahead adding
+ // more pages than needed. In this case just assume misses as total and reset hits.
+ NETDATA_DOUBLE hits = total - misses;
+ if (hits < 0 ) {
+ misses = total;
+ hits = 0;
+ }
+
+ NETDATA_DOUBLE ratio = (total > 0) ? hits/total : 1;
+
+ out->ratio = (long long )(ratio*100);
+ out->hit = (long long)hits;
+ out->miss = (long long)misses;
+}
+
+/**
+ * Save previous values
+ *
+ * Save values used this time.
+ *
+ * @param publish
+ */
+static void save_previous_values(netdata_publish_cachestat_t *publish) {
+ publish->prev.mark_page_accessed = cachestat_hash_values[NETDATA_KEY_CALLS_MARK_PAGE_ACCESSED];
+ publish->prev.account_page_dirtied = cachestat_hash_values[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED];
+ publish->prev.add_to_page_cache_lru = cachestat_hash_values[NETDATA_KEY_CALLS_ADD_TO_PAGE_CACHE_LRU];
+ publish->prev.mark_buffer_dirty = cachestat_hash_values[NETDATA_KEY_CALLS_MARK_BUFFER_DIRTY];
+}
+
+/**
+ * Calculate statistics
+ *
+ * @param publish the structure where we will store the data.
+ */
+static void calculate_stats(netdata_publish_cachestat_t *publish) {
+ if (!publish->prev.mark_page_accessed) {
+ save_previous_values(publish);
+ return;
+ }
+
+ uint64_t mpa = cachestat_hash_values[NETDATA_KEY_CALLS_MARK_PAGE_ACCESSED] - publish->prev.mark_page_accessed;
+ uint64_t mbd = cachestat_hash_values[NETDATA_KEY_CALLS_MARK_BUFFER_DIRTY] - publish->prev.mark_buffer_dirty;
+ uint64_t apcl = cachestat_hash_values[NETDATA_KEY_CALLS_ADD_TO_PAGE_CACHE_LRU] - publish->prev.add_to_page_cache_lru;
+ uint64_t apd = cachestat_hash_values[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED] - publish->prev.account_page_dirtied;
+
+ save_previous_values(publish);
+
+ // We are changing the original algorithm to have a smooth ratio.
+ cachestat_update_publish(publish, mpa, mbd, apcl, apd);
+}
+
+
+/*****************************************************************
+ *
+ * APPS
+ *
+ *****************************************************************/
+
+/**
+ * Apps Accumulator
+ *
+ * Sum all values read from kernel and store in the first address.
+ *
+ * @param out the vector with read values.
+ */
+static void cachestat_apps_accumulator(netdata_cachestat_pid_t *out)
+{
+ int i, end = (running_on_kernel >= NETDATA_KERNEL_V4_15) ? ebpf_nprocs : 1;
+ netdata_cachestat_pid_t *total = &out[0];
+ for (i = 1; i < end; i++) {
+ netdata_cachestat_pid_t *w = &out[i];
+ total->account_page_dirtied += w->account_page_dirtied;
+ total->add_to_page_cache_lru += w->add_to_page_cache_lru;
+ total->mark_buffer_dirty += w->mark_buffer_dirty;
+ total->mark_page_accessed += w->mark_page_accessed;
+ }
+}
+
+/**
+ * Save Pid values
+ *
+ * Save the current values inside the structure
+ *
+ * @param out vector used to plot charts
+ * @param publish vector with values read from hash tables.
+ */
+static inline void cachestat_save_pid_values(netdata_publish_cachestat_t *out, netdata_cachestat_pid_t *publish)
+{
+ if (!out->current.mark_page_accessed) {
+ memcpy(&out->current, &publish[0], sizeof(netdata_cachestat_pid_t));
+ return;
+ }
+
+ memcpy(&out->prev, &out->current, sizeof(netdata_cachestat_pid_t));
+ memcpy(&out->current, &publish[0], sizeof(netdata_cachestat_pid_t));
+}
+
+/**
+ * Fill PID
+ *
+ * Fill PID structures
+ *
+ * @param current_pid pid that we are collecting data
+ * @param out values read from hash tables;
+ */
+static void cachestat_fill_pid(uint32_t current_pid, netdata_cachestat_pid_t *publish)
+{
+ netdata_publish_cachestat_t *curr = cachestat_pid[current_pid];
+ if (!curr) {
+ curr = callocz(1, sizeof(netdata_publish_cachestat_t));
+ cachestat_pid[current_pid] = curr;
+
+ cachestat_save_pid_values(curr, publish);
+ return;
+ }
+
+ cachestat_save_pid_values(curr, publish);
+}
+
+/**
+ * Read APPS table
+ *
+ * Read the apps table and store data inside the structure.
+ */
+static void read_apps_table()
+{
+ netdata_cachestat_pid_t *cv = cachestat_vector;
+ uint32_t key;
+ struct pid_stat *pids = root_of_pids;
+ int fd = cachestat_maps[NETDATA_CACHESTAT_PID_STATS].map_fd;
+ size_t length = sizeof(netdata_cachestat_pid_t)*ebpf_nprocs;
+ while (pids) {
+ key = pids->pid;
+
+ if (bpf_map_lookup_elem(fd, &key, cv)) {
+ pids = pids->next;
+ continue;
+ }
+
+ cachestat_apps_accumulator(cv);
+
+ cachestat_fill_pid(key, cv);
+
+ // We are cleaning to avoid passing data read from one process to other.
+ memset(cv, 0, length);
+
+ pids = pids->next;
+ }
+}
+
+/**
+ * Update cgroup
+ *
+ * Update cgroup data based in
+ */
+static void ebpf_update_cachestat_cgroup()
+{
+ netdata_cachestat_pid_t *cv = cachestat_vector;
+ int fd = cachestat_maps[NETDATA_CACHESTAT_PID_STATS].map_fd;
+ size_t length = sizeof(netdata_cachestat_pid_t) * ebpf_nprocs;
+
+ ebpf_cgroup_target_t *ect;
+ pthread_mutex_lock(&mutex_cgroup_shm);
+ for (ect = ebpf_cgroup_pids; ect; ect = ect->next) {
+ struct pid_on_target2 *pids;
+ for (pids = ect->pids; pids; pids = pids->next) {
+ int pid = pids->pid;
+ netdata_cachestat_pid_t *out = &pids->cachestat;
+ if (likely(cachestat_pid) && cachestat_pid[pid]) {
+ netdata_publish_cachestat_t *in = cachestat_pid[pid];
+
+ memcpy(out, &in->current, sizeof(netdata_cachestat_pid_t));
+ } else {
+ memset(cv, 0, length);
+ if (bpf_map_lookup_elem(fd, &pid, cv)) {
+ continue;
+ }
+
+ cachestat_apps_accumulator(cv);
+
+ memcpy(out, cv, sizeof(netdata_cachestat_pid_t));
+ }
+ }
+ }
+ pthread_mutex_unlock(&mutex_cgroup_shm);
+}
+
+/**
+ * Create apps charts
+ *
+ * Call ebpf_create_chart to create the charts on apps submenu.
+ *
+ * @param em a pointer to the structure with the default values.
+ */
+void ebpf_cachestat_create_apps_charts(struct ebpf_module *em, void *ptr)
+{
+ struct target *root = ptr;
+ ebpf_create_charts_on_apps(NETDATA_CACHESTAT_HIT_RATIO_CHART,
+ "Hit ratio",
+ EBPF_COMMON_DIMENSION_PERCENTAGE,
+ NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_LINE,
+ 20090,
+ ebpf_algorithms[NETDATA_EBPF_ABSOLUTE_IDX],
+ root, em->update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ ebpf_create_charts_on_apps(NETDATA_CACHESTAT_DIRTY_CHART,
+ "Number of dirty pages",
+ EBPF_CACHESTAT_DIMENSION_PAGE,
+ NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_STACKED,
+ 20091,
+ ebpf_algorithms[NETDATA_EBPF_INCREMENTAL_IDX],
+ root, em->update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ ebpf_create_charts_on_apps(NETDATA_CACHESTAT_HIT_CHART,
+ "Number of accessed files",
+ EBPF_CACHESTAT_DIMENSION_HITS,
+ NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_STACKED,
+ 20092,
+ ebpf_algorithms[NETDATA_EBPF_ABSOLUTE_IDX],
+ root, em->update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ ebpf_create_charts_on_apps(NETDATA_CACHESTAT_MISSES_CHART,
+ "Files out of page cache",
+ EBPF_CACHESTAT_DIMENSION_MISSES,
+ NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_STACKED,
+ 20093,
+ ebpf_algorithms[NETDATA_EBPF_ABSOLUTE_IDX],
+ root, em->update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ em->apps_charts |= NETDATA_EBPF_APPS_FLAG_CHART_CREATED;
+}
+
+/*****************************************************************
+ *
+ * MAIN LOOP
+ *
+ *****************************************************************/
+
+/**
+ * Read global counter
+ *
+ * Read the table with number of calls for all functions
+ */
+static void read_global_table()
+{
+ uint32_t idx;
+ netdata_idx_t *val = cachestat_hash_values;
+ netdata_idx_t *stored = cachestat_values;
+ int fd = cachestat_maps[NETDATA_CACHESTAT_GLOBAL_STATS].map_fd;
+
+ for (idx = NETDATA_KEY_CALLS_ADD_TO_PAGE_CACHE_LRU; idx < NETDATA_CACHESTAT_END; idx++) {
+ if (!bpf_map_lookup_elem(fd, &idx, stored)) {
+ int i;
+ int end = ebpf_nprocs;
+ netdata_idx_t total = 0;
+ for (i = 0; i < end; i++)
+ total += stored[i];
+
+ val[idx] = total;
+ }
+ }
+}
+
+/**
+ * Socket 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_cachestat_read_hash(void *ptr)
+{
+ netdata_thread_cleanup_push(ebpf_cachestat_cleanup, ptr);
+ heartbeat_t hb;
+ heartbeat_init(&hb);
+
+ ebpf_module_t *em = (ebpf_module_t *)ptr;
+
+ usec_t step = NETDATA_LATENCY_CACHESTAT_SLEEP_MS * em->update_every;
+ while (!ebpf_exit_plugin) {
+ (void)heartbeat_next(&hb, step);
+
+ read_global_table();
+ }
+
+ netdata_thread_cleanup_pop(1);
+ return NULL;
+}
+
+/**
+ * Send global
+ *
+ * Send global charts to Netdata
+ */
+static void cachestat_send_global(netdata_publish_cachestat_t *publish)
+{
+ calculate_stats(publish);
+
+ netdata_publish_syscall_t *ptr = cachestat_counter_publish_aggregated;
+ ebpf_one_dimension_write_charts(
+ NETDATA_EBPF_MEMORY_GROUP, NETDATA_CACHESTAT_HIT_RATIO_CHART, ptr[NETDATA_CACHESTAT_IDX_RATIO].dimension,
+ publish->ratio);
+
+ ebpf_one_dimension_write_charts(
+ NETDATA_EBPF_MEMORY_GROUP, NETDATA_CACHESTAT_DIRTY_CHART, ptr[NETDATA_CACHESTAT_IDX_DIRTY].dimension,
+ cachestat_hash_values[NETDATA_KEY_CALLS_MARK_BUFFER_DIRTY]);
+
+ ebpf_one_dimension_write_charts(
+ NETDATA_EBPF_MEMORY_GROUP, NETDATA_CACHESTAT_HIT_CHART, ptr[NETDATA_CACHESTAT_IDX_HIT].dimension, publish->hit);
+
+ ebpf_one_dimension_write_charts(
+ NETDATA_EBPF_MEMORY_GROUP, NETDATA_CACHESTAT_MISSES_CHART, ptr[NETDATA_CACHESTAT_IDX_MISS].dimension,
+ publish->miss);
+}
+
+/**
+ * Cachestat sum PIDs
+ *
+ * Sum values for all PIDs associated to a group
+ *
+ * @param publish output structure.
+ * @param root structure with listed IPs
+ */
+void ebpf_cachestat_sum_pids(netdata_publish_cachestat_t *publish, struct pid_on_target *root)
+{
+ memcpy(&publish->prev, &publish->current,sizeof(publish->current));
+ memset(&publish->current, 0, sizeof(publish->current));
+
+ netdata_cachestat_pid_t *dst = &publish->current;
+ while (root) {
+ int32_t pid = root->pid;
+ netdata_publish_cachestat_t *w = cachestat_pid[pid];
+ if (w) {
+ netdata_cachestat_pid_t *src = &w->current;
+ dst->account_page_dirtied += src->account_page_dirtied;
+ dst->add_to_page_cache_lru += src->add_to_page_cache_lru;
+ dst->mark_buffer_dirty += src->mark_buffer_dirty;
+ dst->mark_page_accessed += src->mark_page_accessed;
+ }
+
+ root = root->next;
+ }
+}
+
+/**
+ * Send data to Netdata calling auxiliary functions.
+ *
+ * @param root the target list.
+*/
+void ebpf_cache_send_apps_data(struct target *root)
+{
+ struct target *w;
+ collected_number value;
+
+ write_begin_chart(NETDATA_APPS_FAMILY, NETDATA_CACHESTAT_HIT_RATIO_CHART);
+ for (w = root; w; w = w->next) {
+ if (unlikely(w->exposed && w->processes)) {
+ ebpf_cachestat_sum_pids(&w->cachestat, w->root_pid);
+ netdata_cachestat_pid_t *current = &w->cachestat.current;
+ netdata_cachestat_pid_t *prev = &w->cachestat.prev;
+
+ uint64_t mpa = current->mark_page_accessed - prev->mark_page_accessed;
+ uint64_t mbd = current->mark_buffer_dirty - prev->mark_buffer_dirty;
+ w->cachestat.dirty = mbd;
+ uint64_t apcl = current->add_to_page_cache_lru - prev->add_to_page_cache_lru;
+ uint64_t apd = current->account_page_dirtied - prev->account_page_dirtied;
+
+ cachestat_update_publish(&w->cachestat, mpa, mbd, apcl, apd);
+ value = (collected_number) w->cachestat.ratio;
+ // Here we are using different approach to have a chart more smooth
+ write_chart_dimension(w->name, value);
+ }
+ }
+ write_end_chart();
+
+ write_begin_chart(NETDATA_APPS_FAMILY, NETDATA_CACHESTAT_DIRTY_CHART);
+ for (w = root; w; w = w->next) {
+ if (unlikely(w->exposed && w->processes)) {
+ value = (collected_number) w->cachestat.dirty;
+ write_chart_dimension(w->name, value);
+ }
+ }
+ write_end_chart();
+
+ write_begin_chart(NETDATA_APPS_FAMILY, NETDATA_CACHESTAT_HIT_CHART);
+ for (w = root; w; w = w->next) {
+ if (unlikely(w->exposed && w->processes)) {
+ value = (collected_number) w->cachestat.hit;
+ write_chart_dimension(w->name, value);
+ }
+ }
+ write_end_chart();
+
+ write_begin_chart(NETDATA_APPS_FAMILY, NETDATA_CACHESTAT_MISSES_CHART);
+ for (w = root; w; w = w->next) {
+ if (unlikely(w->exposed && w->processes)) {
+ value = (collected_number) w->cachestat.miss;
+ write_chart_dimension(w->name, value);
+ }
+ }
+ write_end_chart();
+}
+
+/**
+ * Cachestat sum PIDs
+ *
+ * Sum values for all PIDs associated to a group
+ *
+ * @param publish output structure.
+ * @param root structure with listed IPs
+ */
+void ebpf_cachestat_sum_cgroup_pids(netdata_publish_cachestat_t *publish, struct pid_on_target2 *root)
+{
+ memcpy(&publish->prev, &publish->current,sizeof(publish->current));
+ memset(&publish->current, 0, sizeof(publish->current));
+
+ netdata_cachestat_pid_t *dst = &publish->current;
+ while (root) {
+ netdata_cachestat_pid_t *src = &root->cachestat;
+
+ dst->account_page_dirtied += src->account_page_dirtied;
+ dst->add_to_page_cache_lru += src->add_to_page_cache_lru;
+ dst->mark_buffer_dirty += src->mark_buffer_dirty;
+ dst->mark_page_accessed += src->mark_page_accessed;
+
+ root = root->next;
+ }
+}
+
+/**
+ * Calc chart values
+ *
+ * Do necessary math to plot charts.
+ */
+void ebpf_cachestat_calc_chart_values()
+{
+ ebpf_cgroup_target_t *ect;
+ for (ect = ebpf_cgroup_pids; ect ; ect = ect->next) {
+ ebpf_cachestat_sum_cgroup_pids(&ect->publish_cachestat, ect->pids);
+
+ netdata_cachestat_pid_t *current = &ect->publish_cachestat.current;
+ netdata_cachestat_pid_t *prev = &ect->publish_cachestat.prev;
+
+ uint64_t mpa = current->mark_page_accessed - prev->mark_page_accessed;
+ uint64_t mbd = current->mark_buffer_dirty - prev->mark_buffer_dirty;
+ ect->publish_cachestat.dirty = mbd;
+ uint64_t apcl = current->add_to_page_cache_lru - prev->add_to_page_cache_lru;
+ uint64_t apd = current->account_page_dirtied - prev->account_page_dirtied;
+
+ cachestat_update_publish(&ect->publish_cachestat, mpa, mbd, apcl, apd);
+ }
+}
+
+/**
+ * Create Systemd cachestat Charts
+ *
+ * Create charts when systemd is enabled
+ *
+ * @param update_every value to overwrite the update frequency set by the server.
+ **/
+static void ebpf_create_systemd_cachestat_charts(int update_every)
+{
+ ebpf_create_charts_on_systemd(NETDATA_CACHESTAT_HIT_RATIO_CHART,
+ "Hit ratio",
+ EBPF_COMMON_DIMENSION_PERCENTAGE, NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_LINE, 21100,
+ ebpf_algorithms[NETDATA_EBPF_ABSOLUTE_IDX],
+ NETDATA_SYSTEMD_CACHESTAT_HIT_RATIO_CONTEXT, NETDATA_EBPF_MODULE_NAME_CACHESTAT,
+ update_every);
+
+ ebpf_create_charts_on_systemd(NETDATA_CACHESTAT_DIRTY_CHART,
+ "Number of dirty pages",
+ EBPF_CACHESTAT_DIMENSION_PAGE, NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_LINE, 21101,
+ ebpf_algorithms[NETDATA_EBPF_ABSOLUTE_IDX],
+ NETDATA_SYSTEMD_CACHESTAT_MODIFIED_CACHE_CONTEXT, NETDATA_EBPF_MODULE_NAME_CACHESTAT,
+ update_every);
+
+ ebpf_create_charts_on_systemd(NETDATA_CACHESTAT_HIT_CHART, "Number of accessed files",
+ EBPF_CACHESTAT_DIMENSION_HITS, NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_LINE, 21102,
+ ebpf_algorithms[NETDATA_EBPF_ABSOLUTE_IDX],
+ NETDATA_SYSTEMD_CACHESTAT_HIT_FILE_CONTEXT, NETDATA_EBPF_MODULE_NAME_CACHESTAT,
+ update_every);
+
+ ebpf_create_charts_on_systemd(NETDATA_CACHESTAT_MISSES_CHART, "Files out of page cache",
+ EBPF_CACHESTAT_DIMENSION_MISSES, NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_LINE, 21103,
+ ebpf_algorithms[NETDATA_EBPF_ABSOLUTE_IDX],
+ NETDATA_SYSTEMD_CACHESTAT_MISS_FILES_CONTEXT, NETDATA_EBPF_MODULE_NAME_CACHESTAT,
+ update_every);
+}
+
+/**
+ * Send Cache Stat charts
+ *
+ * Send collected data to Netdata.
+ */
+static void ebpf_send_systemd_cachestat_charts()
+{
+ ebpf_cgroup_target_t *ect;
+
+ write_begin_chart(NETDATA_SERVICE_FAMILY, NETDATA_CACHESTAT_HIT_RATIO_CHART);
+ for (ect = ebpf_cgroup_pids; ect; ect = ect->next) {
+ if (unlikely(ect->systemd) && unlikely(ect->updated)) {
+ write_chart_dimension(ect->name, (long long)ect->publish_cachestat.ratio);
+ }
+ }
+ write_end_chart();
+
+ write_begin_chart(NETDATA_SERVICE_FAMILY, NETDATA_CACHESTAT_DIRTY_CHART);
+ for (ect = ebpf_cgroup_pids; ect; ect = ect->next) {
+ if (unlikely(ect->systemd) && unlikely(ect->updated)) {
+ write_chart_dimension(ect->name, (long long)ect->publish_cachestat.dirty);
+ }
+ }
+ write_end_chart();
+
+ write_begin_chart(NETDATA_SERVICE_FAMILY, NETDATA_CACHESTAT_HIT_CHART);
+ for (ect = ebpf_cgroup_pids; ect; ect = ect->next) {
+ if (unlikely(ect->systemd) && unlikely(ect->updated)) {
+ write_chart_dimension(ect->name, (long long)ect->publish_cachestat.hit);
+ }
+ }
+ write_end_chart();
+
+ write_begin_chart(NETDATA_SERVICE_FAMILY, NETDATA_CACHESTAT_MISSES_CHART);
+ for (ect = ebpf_cgroup_pids; ect; ect = ect->next) {
+ if (unlikely(ect->systemd) && unlikely(ect->updated)) {
+ write_chart_dimension(ect->name, (long long)ect->publish_cachestat.miss);
+ }
+ }
+ write_end_chart();
+}
+
+/**
+ * Send Directory Cache charts
+ *
+ * Send collected data to Netdata.
+ */
+static void ebpf_send_specific_cachestat_data(char *type, netdata_publish_cachestat_t *npc)
+{
+ write_begin_chart(type, NETDATA_CACHESTAT_HIT_RATIO_CHART);
+ write_chart_dimension(cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_RATIO].name, (long long)npc->ratio);
+ write_end_chart();
+
+ write_begin_chart(type, NETDATA_CACHESTAT_DIRTY_CHART);
+ write_chart_dimension(cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_DIRTY].name, (long long)npc->dirty);
+ write_end_chart();
+
+ write_begin_chart(type, NETDATA_CACHESTAT_HIT_CHART);
+ write_chart_dimension(cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_HIT].name, (long long)npc->hit);
+ write_end_chart();
+
+ write_begin_chart(type, NETDATA_CACHESTAT_MISSES_CHART);
+ write_chart_dimension(cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_MISS].name, (long long)npc->miss);
+ write_end_chart();
+}
+
+/**
+ * Create specific cache Stat charts
+ *
+ * Create charts for cgroup/application.
+ *
+ * @param type the chart type.
+ * @param update_every value to overwrite the update frequency set by the server.
+ */
+static void ebpf_create_specific_cachestat_charts(char *type, int update_every)
+{
+ ebpf_create_chart(type, NETDATA_CACHESTAT_HIT_RATIO_CHART,
+ "Hit ratio",
+ EBPF_COMMON_DIMENSION_PERCENTAGE, NETDATA_CACHESTAT_CGROUP_SUBMENU,
+ NETDATA_CGROUP_CACHESTAT_HIT_RATIO_CONTEXT,
+ NETDATA_EBPF_CHART_TYPE_LINE, NETDATA_CHART_PRIO_CGROUPS_CONTAINERS + 5200,
+ ebpf_create_global_dimension,
+ cachestat_counter_publish_aggregated, 1, update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ ebpf_create_chart(type, NETDATA_CACHESTAT_DIRTY_CHART,
+ "Number of dirty pages",
+ EBPF_CACHESTAT_DIMENSION_PAGE, NETDATA_CACHESTAT_CGROUP_SUBMENU,
+ NETDATA_CGROUP_CACHESTAT_MODIFIED_CACHE_CONTEXT,
+ NETDATA_EBPF_CHART_TYPE_LINE, NETDATA_CHART_PRIO_CGROUPS_CONTAINERS + 5201,
+ ebpf_create_global_dimension,
+ &cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_DIRTY], 1,
+ update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ ebpf_create_chart(type, NETDATA_CACHESTAT_HIT_CHART,
+ "Number of accessed files",
+ EBPF_CACHESTAT_DIMENSION_HITS, NETDATA_CACHESTAT_CGROUP_SUBMENU,
+ NETDATA_CGROUP_CACHESTAT_HIT_FILES_CONTEXT,
+ NETDATA_EBPF_CHART_TYPE_LINE, NETDATA_CHART_PRIO_CGROUPS_CONTAINERS + 5202,
+ ebpf_create_global_dimension,
+ &cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_HIT], 1,
+ update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ ebpf_create_chart(type, NETDATA_CACHESTAT_MISSES_CHART,
+ "Files out of page cache",
+ EBPF_CACHESTAT_DIMENSION_MISSES, NETDATA_CACHESTAT_CGROUP_SUBMENU,
+ NETDATA_CGROUP_CACHESTAT_MISS_FILES_CONTEXT,
+ NETDATA_EBPF_CHART_TYPE_LINE, NETDATA_CHART_PRIO_CGROUPS_CONTAINERS + 5203,
+ ebpf_create_global_dimension,
+ &cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_MISS], 1,
+ update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+}
+
+/**
+ * Obsolete specific cache stat charts
+ *
+ * Obsolete charts for cgroup/application.
+ *
+ * @param type the chart type.
+ * @param update_every value to overwrite the update frequency set by the server.
+ */
+static void ebpf_obsolete_specific_cachestat_charts(char *type, int update_every)
+{
+ ebpf_write_chart_obsolete(type, NETDATA_CACHESTAT_HIT_RATIO_CHART,
+ "Hit ratio",
+ EBPF_COMMON_DIMENSION_PERCENTAGE, NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_LINE, NETDATA_CGROUP_CACHESTAT_HIT_RATIO_CONTEXT,
+ NETDATA_CHART_PRIO_CGROUPS_CONTAINERS + 5200, update_every);
+
+ ebpf_write_chart_obsolete(type, NETDATA_CACHESTAT_DIRTY_CHART,
+ "Number of dirty pages",
+ EBPF_CACHESTAT_DIMENSION_PAGE, NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_LINE, NETDATA_CGROUP_CACHESTAT_MODIFIED_CACHE_CONTEXT,
+ NETDATA_CHART_PRIO_CGROUPS_CONTAINERS + 5201, update_every);
+
+ ebpf_write_chart_obsolete(type, NETDATA_CACHESTAT_HIT_CHART,
+ "Number of accessed files",
+ EBPF_CACHESTAT_DIMENSION_HITS, NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_LINE, NETDATA_CGROUP_CACHESTAT_HIT_FILES_CONTEXT,
+ NETDATA_CHART_PRIO_CGROUPS_CONTAINERS + 5202, update_every);
+
+ ebpf_write_chart_obsolete(type, NETDATA_CACHESTAT_MISSES_CHART,
+ "Files out of page cache",
+ EBPF_CACHESTAT_DIMENSION_MISSES, NETDATA_CACHESTAT_SUBMENU,
+ NETDATA_EBPF_CHART_TYPE_LINE, NETDATA_CGROUP_CACHESTAT_MISS_FILES_CONTEXT,
+ NETDATA_CHART_PRIO_CGROUPS_CONTAINERS + 5203, update_every);
+}
+
+/**
+ * Send data to Netdata calling auxiliary functions.
+ *
+ * @param update_every value to overwrite the update frequency set by the server.
+*/
+void ebpf_cachestat_send_cgroup_data(int update_every)
+{
+ if (!ebpf_cgroup_pids)
+ return;
+
+ pthread_mutex_lock(&mutex_cgroup_shm);
+ ebpf_cgroup_target_t *ect;
+ ebpf_cachestat_calc_chart_values();
+
+ int has_systemd = shm_ebpf_cgroup.header->systemd_enabled;
+ if (has_systemd) {
+ if (send_cgroup_chart) {
+ ebpf_create_systemd_cachestat_charts(update_every);
+ }
+
+ ebpf_send_systemd_cachestat_charts();
+ }
+
+ for (ect = ebpf_cgroup_pids; ect ; ect = ect->next) {
+ if (ect->systemd)
+ continue;
+
+ if (!(ect->flags & NETDATA_EBPF_CGROUP_HAS_CACHESTAT_CHART) && ect->updated) {
+ ebpf_create_specific_cachestat_charts(ect->name, update_every);
+ ect->flags |= NETDATA_EBPF_CGROUP_HAS_CACHESTAT_CHART;
+ }
+
+ if (ect->flags & NETDATA_EBPF_CGROUP_HAS_CACHESTAT_CHART) {
+ if (ect->updated) {
+ ebpf_send_specific_cachestat_data(ect->name, &ect->publish_cachestat);
+ } else {
+ ebpf_obsolete_specific_cachestat_charts(ect->name, update_every);
+ ect->flags &= ~NETDATA_EBPF_CGROUP_HAS_CACHESTAT_CHART;
+ }
+ }
+ }
+
+ pthread_mutex_unlock(&mutex_cgroup_shm);
+}
+
+/**
+* Main loop for this collector.
+*/
+static void cachestat_collector(ebpf_module_t *em)
+{
+ cachestat_threads.thread = callocz(1, sizeof(netdata_thread_t));
+ cachestat_threads.start_routine = ebpf_cachestat_read_hash;
+
+ netdata_thread_create(cachestat_threads.thread, cachestat_threads.name, NETDATA_THREAD_OPTION_DEFAULT,
+ ebpf_cachestat_read_hash, em);
+
+ netdata_publish_cachestat_t publish;
+ memset(&publish, 0, sizeof(publish));
+ int cgroups = em->cgroup_charts;
+ int update_every = em->update_every;
+ heartbeat_t hb;
+ heartbeat_init(&hb);
+ usec_t step = update_every * USEC_PER_SEC;
+ //This will be cancelled by its parent
+ while (!ebpf_exit_plugin) {
+ (void)heartbeat_next(&hb, step);
+ if (ebpf_exit_plugin)
+ break;
+
+ netdata_apps_integration_flags_t apps = em->apps_charts;
+ pthread_mutex_lock(&collect_data_mutex);
+ if (apps)
+ read_apps_table();
+
+ if (cgroups)
+ ebpf_update_cachestat_cgroup();
+
+ pthread_mutex_lock(&lock);
+
+ cachestat_send_global(&publish);
+
+ if (apps & NETDATA_EBPF_APPS_FLAG_CHART_CREATED)
+ ebpf_cache_send_apps_data(apps_groups_root_target);
+
+ if (cgroups)
+ ebpf_cachestat_send_cgroup_data(update_every);
+
+ pthread_mutex_unlock(&lock);
+ pthread_mutex_unlock(&collect_data_mutex);
+ }
+}
+
+/*****************************************************************
+ *
+ * INITIALIZE THREAD
+ *
+ *****************************************************************/
+
+/**
+ * Create global charts
+ *
+ * Call ebpf_create_chart to create the charts for the collector.
+ *
+ * @param em a pointer to `struct ebpf_module`
+ */
+static void ebpf_create_memory_charts(ebpf_module_t *em)
+{
+ ebpf_create_chart(NETDATA_EBPF_MEMORY_GROUP, NETDATA_CACHESTAT_HIT_RATIO_CHART,
+ "Hit ratio",
+ EBPF_COMMON_DIMENSION_PERCENTAGE, NETDATA_CACHESTAT_SUBMENU,
+ NULL,
+ NETDATA_EBPF_CHART_TYPE_LINE,
+ 21100,
+ ebpf_create_global_dimension,
+ cachestat_counter_publish_aggregated, 1, em->update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ ebpf_create_chart(NETDATA_EBPF_MEMORY_GROUP, NETDATA_CACHESTAT_DIRTY_CHART,
+ "Number of dirty pages",
+ EBPF_CACHESTAT_DIMENSION_PAGE, NETDATA_CACHESTAT_SUBMENU,
+ NULL,
+ NETDATA_EBPF_CHART_TYPE_LINE,
+ 21101,
+ ebpf_create_global_dimension,
+ &cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_DIRTY], 1,
+ em->update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ ebpf_create_chart(NETDATA_EBPF_MEMORY_GROUP, NETDATA_CACHESTAT_HIT_CHART,
+ "Number of accessed files",
+ EBPF_CACHESTAT_DIMENSION_HITS, NETDATA_CACHESTAT_SUBMENU,
+ NULL,
+ NETDATA_EBPF_CHART_TYPE_LINE,
+ 21102,
+ ebpf_create_global_dimension,
+ &cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_HIT], 1,
+ em->update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ ebpf_create_chart(NETDATA_EBPF_MEMORY_GROUP, NETDATA_CACHESTAT_MISSES_CHART,
+ "Files out of page cache",
+ EBPF_CACHESTAT_DIMENSION_MISSES, NETDATA_CACHESTAT_SUBMENU,
+ NULL,
+ NETDATA_EBPF_CHART_TYPE_LINE,
+ 21103,
+ ebpf_create_global_dimension,
+ &cachestat_counter_publish_aggregated[NETDATA_CACHESTAT_IDX_MISS], 1,
+ em->update_every, NETDATA_EBPF_MODULE_NAME_CACHESTAT);
+
+ fflush(stdout);
+}
+
+/**
+ * Allocate vectors used with this thread.
+ *
+ * We are not testing the return, because callocz does this and shutdown the software
+ * case it was not possible to allocate.
+ *
+ * @param apps is apps enabled?
+ */
+static void ebpf_cachestat_allocate_global_vectors(int apps)
+{
+ if (apps)
+ cachestat_pid = callocz((size_t)pid_max, sizeof(netdata_publish_cachestat_t *));
+
+ cachestat_vector = callocz((size_t)ebpf_nprocs, sizeof(netdata_cachestat_pid_t));
+
+ cachestat_values = callocz((size_t)ebpf_nprocs, sizeof(netdata_idx_t));
+
+ memset(cachestat_hash_values, 0, NETDATA_CACHESTAT_END * sizeof(netdata_idx_t));
+ memset(cachestat_counter_aggregated_data, 0, NETDATA_CACHESTAT_END * sizeof(netdata_syscall_stat_t));
+ memset(cachestat_counter_publish_aggregated, 0, NETDATA_CACHESTAT_END * sizeof(netdata_publish_syscall_t));
+}
+
+/*****************************************************************
+ *
+ * MAIN THREAD
+ *
+ *****************************************************************/
+
+/**
+ * Update Internal value
+ *
+ * Update values used during runtime.
+ */
+static void ebpf_cachestat_set_internal_value()
+{
+ static char *account_page[] = { "account_page_dirtied", "__set_page_dirty", "__folio_mark_dirty" };
+ if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_16)
+ cachestat_targets[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED].name = account_page[NETDATA_CACHESTAT_FOLIO_DIRTY];
+ else if (running_on_kernel >= NETDATA_EBPF_KERNEL_5_15)
+ cachestat_targets[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED].name = account_page[NETDATA_CACHESTAT_SET_PAGE_DIRTY];
+ else
+ cachestat_targets[NETDATA_KEY_CALLS_ACCOUNT_PAGE_DIRTIED].name = account_page[NETDATA_CACHESTAT_ACCOUNT_PAGE_DIRTY];
+}
+
+/*
+ * Load BPF
+ *
+ * Load BPF files.
+ *
+ * @param em the structure with configuration
+ */
+static int ebpf_cachestat_load_bpf(ebpf_module_t *em)
+{
+ int ret = 0;
+ ebpf_adjust_apps_cgroup(em, em->targets[NETDATA_KEY_CALLS_ADD_TO_PAGE_CACHE_LRU].mode);
+ if (em->load & EBPF_LOAD_LEGACY) {
+ em->probe_links = ebpf_load_program(ebpf_plugin_dir, em, running_on_kernel, isrh, &em->objects);
+ if (!em->probe_links) {
+ ret = -1;
+ }
+ }
+#ifdef LIBBPF_MAJOR_VERSION
+ else {
+ bpf_obj = cachestat_bpf__open();
+ if (!bpf_obj)
+ ret = -1;
+ else
+ ret = ebpf_cachestat_load_and_attach(bpf_obj, em);
+ }
+#endif
+
+ if (ret)
+ error("%s %s", EBPF_DEFAULT_ERROR_MSG, em->thread_name);
+
+ return ret;
+}
+
+/**
+ * Cachestat thread
+ *
+ * Thread used to make cachestat thread
+ *
+ * @param ptr a pointer to `struct ebpf_module`
+ *
+ * @return It always return NULL
+ */
+void *ebpf_cachestat_thread(void *ptr)
+{
+ netdata_thread_cleanup_push(ebpf_cachestat_exit, ptr);
+
+ ebpf_module_t *em = (ebpf_module_t *)ptr;
+ em->maps = cachestat_maps;
+
+ ebpf_update_pid_table(&cachestat_maps[NETDATA_CACHESTAT_PID_STATS], em);
+
+ ebpf_cachestat_set_internal_value();
+
+#ifdef LIBBPF_MAJOR_VERSION
+ ebpf_adjust_thread_load(em, default_btf);
+#endif
+ if (ebpf_cachestat_load_bpf(em)) {
+ em->thread->enabled = NETDATA_THREAD_EBPF_STOPPED;
+ goto endcachestat;
+ }
+
+ ebpf_cachestat_allocate_global_vectors(em->apps_charts);
+
+ int algorithms[NETDATA_CACHESTAT_END] = {
+ NETDATA_EBPF_ABSOLUTE_IDX, NETDATA_EBPF_INCREMENTAL_IDX, NETDATA_EBPF_ABSOLUTE_IDX, NETDATA_EBPF_ABSOLUTE_IDX
+ };
+
+ ebpf_global_labels(cachestat_counter_aggregated_data, cachestat_counter_publish_aggregated,
+ cachestat_counter_dimension_name, cachestat_counter_dimension_name,
+ algorithms, NETDATA_CACHESTAT_END);
+
+ pthread_mutex_lock(&lock);
+ ebpf_update_stats(&plugin_statistics, em);
+ ebpf_create_memory_charts(em);
+ pthread_mutex_unlock(&lock);
+
+ cachestat_collector(em);
+
+endcachestat:
+ ebpf_update_disabled_plugin_stats(em);
+
+ netdata_thread_cleanup_pop(1);
+ return NULL;
+}