+++ /dev/null
-/*
- * Copyright (C) 2012 David Goulet <dgoulet@efficios.com>
- * Copyright (C) 2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * SPDX-License-Identifier: GPL-2.0-only
- *
- */
-
-#define _LGPL_SOURCE
-#include <inttypes.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <time.h>
-
-#include <common/defaults.h>
-#include <common/error.h>
-#include <common/macros.h>
-#include <common/sessiond-comm/inet.h>
-
-#include <lttng/health-internal.h>
-
-/*
- * An application-specific error state for unregistered thread keeps
- * track of thread errors. A thread reporting a health error, normally
- * unregisters and quits. This makes the TLS health state not available
- * to the health_check_state() call so on unregister we update this
- * global error array so we can keep track of which thread was on error
- * if the TLS health state has been removed.
- */
-struct health_app {
- /* List of health state, for each application thread */
- struct cds_list_head list;
- /*
- * This lock ensures that TLS memory used for the node and its
- * container structure don't get reclaimed after the TLS owner
- * thread exits until we have finished using it.
- */
- pthread_mutex_t lock;
- int nr_types;
- struct timespec time_delta;
- /* Health flags containing thread type error state */
- enum health_flags *flags;
-};
-
-/* Define TLS health state. */
-DEFINE_URCU_TLS(struct health_state, health_state);
-
-/*
- * Initialize health check subsytem.
- */
-static
-void health_init(struct health_app *ha)
-{
- /*
- * Get the maximum value between the default delta value and the TCP
- * timeout with a safety net of the default health check delta.
- */
- ha->time_delta.tv_sec = max_t(unsigned long,
- lttcomm_inet_tcp_timeout + DEFAULT_HEALTH_CHECK_DELTA_S,
- ha->time_delta.tv_sec);
- DBG("Health check time delta in seconds set to %lu",
- ha->time_delta.tv_sec);
-}
-
-struct health_app *health_app_create(int nr_types)
-{
- struct health_app *ha;
-
- ha = zmalloc(sizeof(*ha));
- if (!ha) {
- return NULL;
- }
- ha->flags = zmalloc(sizeof(*ha->flags) * nr_types);
- if (!ha->flags) {
- goto error_flags;
- }
- CDS_INIT_LIST_HEAD(&ha->list);
- pthread_mutex_init(&ha->lock, NULL);
- ha->nr_types = nr_types;
- ha->time_delta.tv_sec = DEFAULT_HEALTH_CHECK_DELTA_S;
- ha->time_delta.tv_nsec = DEFAULT_HEALTH_CHECK_DELTA_NS;
- health_init(ha);
- return ha;
-
-error_flags:
- free(ha);
- return NULL;
-}
-
-void health_app_destroy(struct health_app *ha)
-{
- free(ha->flags);
- free(ha);
-}
-
-/*
- * Lock health state global list mutex.
- */
-static void state_lock(struct health_app *ha)
-{
- pthread_mutex_lock(&ha->lock);
-}
-
-/*
- * Unlock health state global list mutex.
- */
-static void state_unlock(struct health_app *ha)
-{
- pthread_mutex_unlock(&ha->lock);
-}
-
-/*
- * Set time difference in res from time_a and time_b.
- */
-static void time_diff(const struct timespec *time_a,
- const struct timespec *time_b, struct timespec *res)
-{
- if (time_a->tv_nsec - time_b->tv_nsec < 0) {
- res->tv_sec = time_a->tv_sec - time_b->tv_sec - 1;
- res->tv_nsec = 1000000000L + time_a->tv_sec - time_b->tv_sec;
- } else {
- res->tv_sec = time_a->tv_sec - time_b->tv_sec;
- res->tv_nsec = time_a->tv_nsec - time_b->tv_nsec;
- }
-}
-
-/*
- * Return true if time_a - time_b > diff, else false.
- */
-static int time_diff_gt(const struct timespec *time_a,
- const struct timespec *time_b, const struct timespec *diff)
-{
- struct timespec res;
-
- time_diff(time_a, time_b, &res);
- time_diff(&res, diff, &res);
-
- if (res.tv_sec > 0) {
- return 1;
- } else if (res.tv_sec == 0 && res.tv_nsec > 0) {
- return 1;
- }
-
- return 0;
-}
-
-/*
- * Validate health state. Checks for the error flag or health conditions.
- *
- * Return 0 if health is bad or else 1.
- */
-static int validate_state(struct health_app *ha, struct health_state *state)
-{
- int retval = 1, ret;
- unsigned long current, last;
- struct timespec current_time;
-
- LTTNG_ASSERT(state);
-
- last = state->last;
- current = uatomic_read(&state->current);
-
- ret = lttng_clock_gettime(CLOCK_MONOTONIC, ¤t_time);
- if (ret < 0) {
- PERROR("Error reading time\n");
- /* error */
- retval = 0;
- goto end;
- }
-
- /*
- * Thread is in bad health if flag HEALTH_ERROR is set. It is also in bad
- * health if, after the delta delay has passed, its the progress counter
- * has not moved and it has NOT been waiting for a poll() call.
- */
- if (uatomic_read(&state->flags) & HEALTH_ERROR) {
- retval = 0;
- goto end;
- }
-
- /*
- * Initial condition need to update the last counter and sample time, but
- * should not check health in this initial case, because we don't know how
- * much time has passed.
- */
- if (state->last_time.tv_sec == 0 && state->last_time.tv_nsec == 0) {
- /* update last counter and last sample time */
- state->last = current;
- memcpy(&state->last_time, ¤t_time, sizeof(current_time));
- } else {
- if (time_diff_gt(¤t_time, &state->last_time,
- &ha->time_delta)) {
- if (current == last && !HEALTH_IS_IN_POLL(current)) {
- /* error */
- retval = 0;
- }
- /* update last counter and last sample time */
- state->last = current;
- memcpy(&state->last_time, ¤t_time, sizeof(current_time));
-
- /* On error, stop right now and notify caller. */
- if (retval == 0) {
- goto end;
- }
- }
- }
-
-end:
- DBG("Health state current %lu, last %lu, ret %d",
- current, last, ret);
- return retval;
-}
-
-/*
- * Check health of a specific health type. Note that if a thread has not yet
- * initialize its health subsystem or has quit, it's considered in a good
- * state.
- *
- * Return 0 if health is bad or else 1.
- */
-int health_check_state(struct health_app *ha, int type)
-{
- int retval = 1;
- struct health_state *state;
-
- LTTNG_ASSERT(type < ha->nr_types);
-
- state_lock(ha);
-
- cds_list_for_each_entry(state, &ha->list, node) {
- int ret;
-
- if (state->type != type) {
- continue;
- }
-
- ret = validate_state(ha, state);
- if (!ret) {
- retval = 0;
- goto end;
- }
- }
-
- /* Check the global state since some state might not be visible anymore. */
- if (ha->flags[type] & HEALTH_ERROR) {
- retval = 0;
- }
-
-end:
- state_unlock(ha);
-
- DBG("Health check for type %d is %s", (int) type,
- (retval == 0) ? "BAD" : "GOOD");
- return retval;
-}
-
-/*
- * Init health state.
- */
-void health_register(struct health_app *ha, int type)
-{
- LTTNG_ASSERT(type < ha->nr_types);
-
- /* Init TLS state. */
- uatomic_set(&URCU_TLS(health_state).last, 0);
- uatomic_set(&URCU_TLS(health_state).last_time.tv_sec, 0);
- uatomic_set(&URCU_TLS(health_state).last_time.tv_nsec, 0);
- uatomic_set(&URCU_TLS(health_state).current, 0);
- uatomic_set(&URCU_TLS(health_state).flags, 0);
- uatomic_set(&URCU_TLS(health_state).type, type);
-
- /* Add it to the global TLS state list. */
- state_lock(ha);
- cds_list_add(&URCU_TLS(health_state).node, &ha->list);
- state_unlock(ha);
-}
-
-/*
- * Remove node from global list.
- */
-void health_unregister(struct health_app *ha)
-{
- state_lock(ha);
- /*
- * On error, set the global_error_state since we are about to remove
- * the node from the global list.
- */
- if (uatomic_read(&URCU_TLS(health_state).flags) & HEALTH_ERROR) {
- uatomic_set(&ha->flags[URCU_TLS(health_state).type],
- HEALTH_ERROR);
- }
- cds_list_del(&URCU_TLS(health_state).node);
- state_unlock(ha);
-}
projects / lttng-tools.git / blobdiff