Commit | Line | Data |
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44a5e5eb | 1 | /* |
ab5be9fa MJ |
2 | * Copyright (C) 2012 David Goulet <dgoulet@efficios.com> |
3 | * Copyright (C) 2013 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
44a5e5eb | 4 | * |
ab5be9fa | 5 | * SPDX-License-Identifier: GPL-2.0-only |
44a5e5eb | 6 | * |
44a5e5eb DG |
7 | */ |
8 | ||
6c1c0768 | 9 | #define _LGPL_SOURCE |
44a5e5eb DG |
10 | #include <assert.h> |
11 | #include <inttypes.h> | |
12 | #include <stdio.h> | |
13 | #include <stdlib.h> | |
8809eec0 | 14 | #include <time.h> |
44a5e5eb | 15 | |
8809eec0 | 16 | #include <common/defaults.h> |
44a5e5eb | 17 | #include <common/error.h> |
67e05644 DG |
18 | #include <common/macros.h> |
19 | #include <common/sessiond-comm/inet.h> | |
44a5e5eb | 20 | |
55d09795 | 21 | #include <lttng/health-internal.h> |
44a5e5eb | 22 | |
8782cc74 MD |
23 | /* |
24 | * An application-specific error state for unregistered thread keeps | |
25 | * track of thread errors. A thread reporting a health error, normally | |
26 | * unregisters and quits. This makes the TLS health state not available | |
27 | * to the health_check_state() call so on unregister we update this | |
28 | * global error array so we can keep track of which thread was on error | |
29 | * if the TLS health state has been removed. | |
30 | */ | |
31 | struct health_app { | |
32 | /* List of health state, for each application thread */ | |
33 | struct cds_list_head list; | |
34 | /* | |
35 | * This lock ensures that TLS memory used for the node and its | |
36 | * container structure don't get reclaimed after the TLS owner | |
37 | * thread exits until we have finished using it. | |
38 | */ | |
39 | pthread_mutex_t lock; | |
40 | int nr_types; | |
41 | struct timespec time_delta; | |
42 | /* Health flags containing thread type error state */ | |
43 | enum health_flags *flags; | |
8809eec0 MD |
44 | }; |
45 | ||
927ca06a DG |
46 | /* Define TLS health state. */ |
47 | DEFINE_URCU_TLS(struct health_state, health_state); | |
48 | ||
55d09795 MD |
49 | /* |
50 | * Initialize health check subsytem. | |
51 | */ | |
52 | static | |
53 | void health_init(struct health_app *ha) | |
54 | { | |
55 | /* | |
56 | * Get the maximum value between the default delta value and the TCP | |
57 | * timeout with a safety net of the default health check delta. | |
58 | */ | |
59 | ha->time_delta.tv_sec = max_t(unsigned long, | |
60 | lttcomm_inet_tcp_timeout + DEFAULT_HEALTH_CHECK_DELTA_S, | |
61 | ha->time_delta.tv_sec); | |
62 | DBG("Health check time delta in seconds set to %lu", | |
63 | ha->time_delta.tv_sec); | |
64 | } | |
65 | ||
8782cc74 MD |
66 | struct health_app *health_app_create(int nr_types) |
67 | { | |
68 | struct health_app *ha; | |
927ca06a | 69 | |
8782cc74 MD |
70 | ha = zmalloc(sizeof(*ha)); |
71 | if (!ha) { | |
72 | return NULL; | |
73 | } | |
6c71277b | 74 | ha->flags = zmalloc(sizeof(*ha->flags) * nr_types); |
8782cc74 MD |
75 | if (!ha->flags) { |
76 | goto error_flags; | |
77 | } | |
78 | CDS_INIT_LIST_HEAD(&ha->list); | |
79 | pthread_mutex_init(&ha->lock, NULL); | |
80 | ha->nr_types = nr_types; | |
81 | ha->time_delta.tv_sec = DEFAULT_HEALTH_CHECK_DELTA_S; | |
82 | ha->time_delta.tv_nsec = DEFAULT_HEALTH_CHECK_DELTA_NS; | |
55d09795 | 83 | health_init(ha); |
8782cc74 MD |
84 | return ha; |
85 | ||
86 | error_flags: | |
87 | free(ha); | |
88 | return NULL; | |
89 | } | |
927ca06a | 90 | |
8782cc74 MD |
91 | void health_app_destroy(struct health_app *ha) |
92 | { | |
93 | free(ha->flags); | |
94 | free(ha); | |
95 | } | |
927ca06a DG |
96 | |
97 | /* | |
98 | * Lock health state global list mutex. | |
99 | */ | |
8782cc74 | 100 | static void state_lock(struct health_app *ha) |
927ca06a | 101 | { |
8782cc74 | 102 | pthread_mutex_lock(&ha->lock); |
927ca06a DG |
103 | } |
104 | ||
105 | /* | |
106 | * Unlock health state global list mutex. | |
107 | */ | |
8782cc74 | 108 | static void state_unlock(struct health_app *ha) |
927ca06a | 109 | { |
8782cc74 | 110 | pthread_mutex_unlock(&ha->lock); |
927ca06a DG |
111 | } |
112 | ||
8809eec0 MD |
113 | /* |
114 | * Set time difference in res from time_a and time_b. | |
115 | */ | |
116 | static void time_diff(const struct timespec *time_a, | |
117 | const struct timespec *time_b, struct timespec *res) | |
118 | { | |
119 | if (time_a->tv_nsec - time_b->tv_nsec < 0) { | |
120 | res->tv_sec = time_a->tv_sec - time_b->tv_sec - 1; | |
121 | res->tv_nsec = 1000000000L + time_a->tv_sec - time_b->tv_sec; | |
122 | } else { | |
123 | res->tv_sec = time_a->tv_sec - time_b->tv_sec; | |
931a97e5 | 124 | res->tv_nsec = time_a->tv_nsec - time_b->tv_nsec; |
8809eec0 MD |
125 | } |
126 | } | |
127 | ||
128 | /* | |
129 | * Return true if time_a - time_b > diff, else false. | |
130 | */ | |
131 | static int time_diff_gt(const struct timespec *time_a, | |
132 | const struct timespec *time_b, const struct timespec *diff) | |
133 | { | |
134 | struct timespec res; | |
135 | ||
136 | time_diff(time_a, time_b, &res); | |
137 | time_diff(&res, diff, &res); | |
138 | ||
139 | if (res.tv_sec > 0) { | |
140 | return 1; | |
141 | } else if (res.tv_sec == 0 && res.tv_nsec > 0) { | |
142 | return 1; | |
143 | } | |
144 | ||
145 | return 0; | |
146 | } | |
147 | ||
44a5e5eb | 148 | /* |
c89add41 | 149 | * Validate health state. Checks for the error flag or health conditions. |
44a5e5eb DG |
150 | * |
151 | * Return 0 if health is bad or else 1. | |
152 | */ | |
8782cc74 | 153 | static int validate_state(struct health_app *ha, struct health_state *state) |
44a5e5eb | 154 | { |
8809eec0 | 155 | int retval = 1, ret; |
139ac872 | 156 | unsigned long current, last; |
8809eec0 | 157 | struct timespec current_time; |
927ca06a | 158 | |
c89add41 | 159 | assert(state); |
44a5e5eb | 160 | |
139ac872 | 161 | last = state->last; |
44a5e5eb | 162 | current = uatomic_read(&state->current); |
44a5e5eb | 163 | |
389fbf04 | 164 | ret = lttng_clock_gettime(CLOCK_MONOTONIC, ¤t_time); |
931a97e5 | 165 | if (ret < 0) { |
8809eec0 | 166 | PERROR("Error reading time\n"); |
139ac872 | 167 | /* error */ |
8809eec0 MD |
168 | retval = 0; |
169 | goto end; | |
44a5e5eb DG |
170 | } |
171 | ||
8809eec0 MD |
172 | /* |
173 | * Thread is in bad health if flag HEALTH_ERROR is set. It is also in bad | |
174 | * health if, after the delta delay has passed, its the progress counter | |
175 | * has not moved and it has NOT been waiting for a poll() call. | |
176 | */ | |
177 | if (uatomic_read(&state->flags) & HEALTH_ERROR) { | |
178 | retval = 0; | |
179 | goto end; | |
180 | } | |
44a5e5eb | 181 | |
139ac872 | 182 | /* |
8809eec0 MD |
183 | * Initial condition need to update the last counter and sample time, but |
184 | * should not check health in this initial case, because we don't know how | |
185 | * much time has passed. | |
139ac872 | 186 | */ |
8809eec0 MD |
187 | if (state->last_time.tv_sec == 0 && state->last_time.tv_nsec == 0) { |
188 | /* update last counter and last sample time */ | |
189 | state->last = current; | |
190 | memcpy(&state->last_time, ¤t_time, sizeof(current_time)); | |
191 | } else { | |
8782cc74 MD |
192 | if (time_diff_gt(¤t_time, &state->last_time, |
193 | &ha->time_delta)) { | |
8809eec0 MD |
194 | if (current == last && !HEALTH_IS_IN_POLL(current)) { |
195 | /* error */ | |
196 | retval = 0; | |
197 | } | |
198 | /* update last counter and last sample time */ | |
199 | state->last = current; | |
200 | memcpy(&state->last_time, ¤t_time, sizeof(current_time)); | |
c89add41 DG |
201 | |
202 | /* On error, stop right now and notify caller. */ | |
203 | if (retval == 0) { | |
204 | goto end; | |
205 | } | |
8809eec0 MD |
206 | } |
207 | } | |
208 | ||
209 | end: | |
77c7c900 | 210 | DBG("Health state current %lu, last %lu, ret %d", |
8809eec0 | 211 | current, last, ret); |
c89add41 DG |
212 | return retval; |
213 | } | |
214 | ||
215 | /* | |
216 | * Check health of a specific health type. Note that if a thread has not yet | |
217 | * initialize its health subsystem or has quit, it's considered in a good | |
218 | * state. | |
219 | * | |
220 | * Return 0 if health is bad or else 1. | |
221 | */ | |
8782cc74 | 222 | int health_check_state(struct health_app *ha, int type) |
c89add41 DG |
223 | { |
224 | int retval = 1; | |
225 | struct health_state *state; | |
226 | ||
8782cc74 | 227 | assert(type < ha->nr_types); |
c89add41 | 228 | |
8782cc74 | 229 | state_lock(ha); |
c89add41 | 230 | |
8782cc74 | 231 | cds_list_for_each_entry(state, &ha->list, node) { |
c89add41 DG |
232 | int ret; |
233 | ||
234 | if (state->type != type) { | |
235 | continue; | |
236 | } | |
237 | ||
8782cc74 | 238 | ret = validate_state(ha, state); |
c89add41 DG |
239 | if (!ret) { |
240 | retval = 0; | |
241 | goto end; | |
242 | } | |
243 | } | |
244 | ||
245 | /* Check the global state since some state might not be visible anymore. */ | |
8782cc74 | 246 | if (ha->flags[type] & HEALTH_ERROR) { |
c89add41 DG |
247 | retval = 0; |
248 | } | |
249 | ||
250 | end: | |
8782cc74 | 251 | state_unlock(ha); |
139ac872 | 252 | |
c89add41 DG |
253 | DBG("Health check for type %d is %s", (int) type, |
254 | (retval == 0) ? "BAD" : "GOOD"); | |
8809eec0 | 255 | return retval; |
44a5e5eb | 256 | } |
927ca06a DG |
257 | |
258 | /* | |
259 | * Init health state. | |
260 | */ | |
8782cc74 | 261 | void health_register(struct health_app *ha, int type) |
927ca06a | 262 | { |
8782cc74 | 263 | assert(type < ha->nr_types); |
927ca06a DG |
264 | |
265 | /* Init TLS state. */ | |
266 | uatomic_set(&URCU_TLS(health_state).last, 0); | |
267 | uatomic_set(&URCU_TLS(health_state).last_time.tv_sec, 0); | |
268 | uatomic_set(&URCU_TLS(health_state).last_time.tv_nsec, 0); | |
269 | uatomic_set(&URCU_TLS(health_state).current, 0); | |
270 | uatomic_set(&URCU_TLS(health_state).flags, 0); | |
271 | uatomic_set(&URCU_TLS(health_state).type, type); | |
272 | ||
273 | /* Add it to the global TLS state list. */ | |
8782cc74 MD |
274 | state_lock(ha); |
275 | cds_list_add(&URCU_TLS(health_state).node, &ha->list); | |
276 | state_unlock(ha); | |
927ca06a DG |
277 | } |
278 | ||
279 | /* | |
280 | * Remove node from global list. | |
281 | */ | |
8782cc74 | 282 | void health_unregister(struct health_app *ha) |
927ca06a | 283 | { |
8782cc74 | 284 | state_lock(ha); |
927ca06a DG |
285 | /* |
286 | * On error, set the global_error_state since we are about to remove | |
287 | * the node from the global list. | |
288 | */ | |
289 | if (uatomic_read(&URCU_TLS(health_state).flags) & HEALTH_ERROR) { | |
8782cc74 | 290 | uatomic_set(&ha->flags[URCU_TLS(health_state).type], |
927ca06a DG |
291 | HEALTH_ERROR); |
292 | } | |
293 | cds_list_del(&URCU_TLS(health_state).node); | |
8782cc74 | 294 | state_unlock(ha); |
927ca06a | 295 | } |