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1 | /* SPDX-License-Identifier: (GPL-2.0-only OR LGPL-2.1-only) |
2 | * | |
3 | * counter.c | |
4 | * | |
5 | * Copyright (C) 2020 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
6 | */ | |
7 | ||
8 | #include <linux/module.h> | |
9 | #include <linux/slab.h> | |
10 | #include <lttng/tracer.h> | |
11 | #include <linux/cpumask.h> | |
12 | #include <counter/counter.h> | |
13 | #include <counter/counter-internal.h> | |
14 | #include <wrapper/vmalloc.h> | |
15 | ||
16 | static size_t lttng_counter_get_dimension_nr_elements(struct lib_counter_dimension *dimension) | |
17 | { | |
18 | return dimension->max_nr_elem; | |
19 | } | |
20 | ||
21 | static int lttng_counter_init_stride(const struct lib_counter_config *config, | |
22 | struct lib_counter *counter) | |
23 | { | |
24 | size_t nr_dimensions = counter->nr_dimensions; | |
25 | size_t stride = 1; | |
26 | ssize_t i; | |
27 | ||
28 | for (i = nr_dimensions - 1; i >= 0; i--) { | |
29 | struct lib_counter_dimension *dimension = &counter->dimensions[i]; | |
30 | size_t nr_elem; | |
31 | ||
32 | nr_elem = lttng_counter_get_dimension_nr_elements(dimension); | |
33 | dimension->stride = stride; | |
34 | /* nr_elem should be minimum 1 for each dimension. */ | |
35 | if (!nr_elem) | |
36 | return -EINVAL; | |
37 | stride *= nr_elem; | |
38 | if (stride > SIZE_MAX / nr_elem) | |
39 | return -EINVAL; | |
40 | } | |
41 | return 0; | |
42 | } | |
43 | ||
44 | static int lttng_counter_layout_init(struct lib_counter *counter, int cpu) | |
45 | { | |
46 | struct lib_counter_layout *layout; | |
47 | size_t counter_size; | |
48 | size_t nr_elem = counter->allocated_elem; | |
49 | ||
50 | if (cpu == -1) | |
51 | layout = &counter->global_counters; | |
52 | else | |
53 | layout = per_cpu_ptr(counter->percpu_counters, cpu); | |
54 | switch (counter->config.counter_size) { | |
55 | case COUNTER_SIZE_8_BIT: | |
56 | case COUNTER_SIZE_16_BIT: | |
57 | case COUNTER_SIZE_32_BIT: | |
58 | case COUNTER_SIZE_64_BIT: | |
59 | counter_size = (size_t) counter->config.counter_size; | |
60 | break; | |
61 | default: | |
62 | return -EINVAL; | |
63 | } | |
64 | layout->counters = lttng_kvzalloc_node(ALIGN(counter_size * nr_elem, | |
65 | 1 << INTERNODE_CACHE_SHIFT), | |
66 | GFP_KERNEL | __GFP_NOWARN, | |
67 | cpu_to_node(max(cpu, 0))); | |
68 | if (!layout->counters) | |
69 | return -ENOMEM; | |
70 | layout->overflow_bitmap = lttng_kvzalloc_node(ALIGN(ALIGN(nr_elem, 8) / 8, | |
71 | 1 << INTERNODE_CACHE_SHIFT), | |
72 | GFP_KERNEL | __GFP_NOWARN, | |
73 | cpu_to_node(max(cpu, 0))); | |
74 | if (!layout->overflow_bitmap) | |
75 | return -ENOMEM; | |
76 | layout->underflow_bitmap = lttng_kvzalloc_node(ALIGN(ALIGN(nr_elem, 8) / 8, | |
77 | 1 << INTERNODE_CACHE_SHIFT), | |
78 | GFP_KERNEL | __GFP_NOWARN, | |
79 | cpu_to_node(max(cpu, 0))); | |
80 | if (!layout->underflow_bitmap) | |
81 | return -ENOMEM; | |
82 | return 0; | |
83 | } | |
84 | ||
85 | static void lttng_counter_layout_fini(struct lib_counter *counter, int cpu) | |
86 | { | |
87 | struct lib_counter_layout *layout; | |
88 | ||
89 | if (cpu == -1) | |
90 | layout = &counter->global_counters; | |
91 | else | |
92 | layout = per_cpu_ptr(counter->percpu_counters, cpu); | |
93 | ||
94 | lttng_kvfree(layout->counters); | |
95 | lttng_kvfree(layout->overflow_bitmap); | |
96 | lttng_kvfree(layout->underflow_bitmap); | |
97 | } | |
98 | ||
99 | static | |
100 | int lttng_counter_set_global_sum_step(struct lib_counter *counter, | |
101 | int64_t global_sum_step) | |
102 | { | |
103 | if (global_sum_step < 0) | |
104 | return -EINVAL; | |
105 | ||
106 | switch (counter->config.counter_size) { | |
107 | case COUNTER_SIZE_8_BIT: | |
108 | if (global_sum_step > S8_MAX) | |
109 | return -EINVAL; | |
110 | counter->global_sum_step.s8 = (int8_t) global_sum_step; | |
111 | break; | |
112 | case COUNTER_SIZE_16_BIT: | |
113 | if (global_sum_step > S16_MAX) | |
114 | return -EINVAL; | |
115 | counter->global_sum_step.s16 = (int16_t) global_sum_step; | |
116 | break; | |
117 | case COUNTER_SIZE_32_BIT: | |
118 | if (global_sum_step > S32_MAX) | |
119 | return -EINVAL; | |
120 | counter->global_sum_step.s32 = (int32_t) global_sum_step; | |
121 | break; | |
122 | case COUNTER_SIZE_64_BIT: | |
123 | counter->global_sum_step.s64 = global_sum_step; | |
124 | break; | |
125 | default: | |
126 | return -EINVAL; | |
127 | } | |
128 | ||
129 | return 0; | |
130 | } | |
131 | ||
132 | static | |
133 | int validate_args(const struct lib_counter_config *config, | |
134 | size_t nr_dimensions, | |
135 | const size_t *max_nr_elem, | |
136 | int64_t global_sum_step) | |
137 | { | |
138 | if (BITS_PER_LONG != 64 && config->counter_size == COUNTER_SIZE_64_BIT) { | |
139 | WARN_ON_ONCE(1); | |
140 | return -1; | |
141 | } | |
142 | if (!max_nr_elem) | |
143 | return -1; | |
144 | /* | |
145 | * global sum step is only useful with allocating both per-cpu | |
146 | * and global counters. | |
147 | */ | |
148 | if (global_sum_step && (!(config->alloc & COUNTER_ALLOC_GLOBAL) || | |
149 | !(config->alloc & COUNTER_ALLOC_PER_CPU))) | |
150 | return -1; | |
151 | return 0; | |
152 | } | |
153 | ||
154 | struct lib_counter *lttng_counter_create(const struct lib_counter_config *config, | |
155 | size_t nr_dimensions, | |
156 | const size_t *max_nr_elem, | |
157 | int64_t global_sum_step) | |
158 | { | |
159 | struct lib_counter *counter; | |
160 | size_t dimension, nr_elem = 1; | |
161 | int cpu, ret; | |
162 | ||
163 | if (validate_args(config, nr_dimensions, max_nr_elem, global_sum_step)) | |
164 | return NULL; | |
165 | counter = kzalloc(sizeof(struct lib_counter), GFP_KERNEL); | |
166 | if (!counter) | |
167 | return NULL; | |
168 | counter->config = *config; | |
169 | if (lttng_counter_set_global_sum_step(counter, global_sum_step)) | |
170 | goto error_sum_step; | |
171 | counter->nr_dimensions = nr_dimensions; | |
172 | counter->dimensions = kzalloc(nr_dimensions * sizeof(*counter->dimensions), GFP_KERNEL); | |
173 | if (!counter->dimensions) | |
174 | goto error_dimensions; | |
175 | for (dimension = 0; dimension < nr_dimensions; dimension++) | |
176 | counter->dimensions[dimension].max_nr_elem = max_nr_elem[dimension]; | |
177 | if (config->alloc & COUNTER_ALLOC_PER_CPU) { | |
178 | counter->percpu_counters = alloc_percpu(struct lib_counter_layout); | |
179 | if (!counter->percpu_counters) | |
180 | goto error_alloc_percpu; | |
181 | } | |
182 | ||
183 | if (lttng_counter_init_stride(config, counter)) | |
184 | goto error_init_stride; | |
185 | //TODO saturation values. | |
186 | for (dimension = 0; dimension < counter->nr_dimensions; dimension++) | |
187 | nr_elem *= lttng_counter_get_dimension_nr_elements(&counter->dimensions[dimension]); | |
188 | counter->allocated_elem = nr_elem; | |
189 | if (config->alloc & COUNTER_ALLOC_GLOBAL) { | |
190 | ret = lttng_counter_layout_init(counter, -1); /* global */ | |
191 | if (ret) | |
192 | goto layout_init_error; | |
193 | } | |
194 | if (config->alloc & COUNTER_ALLOC_PER_CPU) { | |
195 | //TODO: integrate with CPU hotplug and online cpus | |
196 | for (cpu = 0; cpu < num_possible_cpus(); cpu++) { | |
197 | ret = lttng_counter_layout_init(counter, cpu); | |
198 | if (ret) | |
199 | goto layout_init_error; | |
200 | } | |
201 | } | |
202 | return counter; | |
203 | ||
204 | layout_init_error: | |
205 | if (config->alloc & COUNTER_ALLOC_PER_CPU) { | |
206 | for (cpu = 0; cpu < num_possible_cpus(); cpu++) | |
207 | lttng_counter_layout_fini(counter, cpu); | |
208 | } | |
209 | if (config->alloc & COUNTER_ALLOC_GLOBAL) | |
210 | lttng_counter_layout_fini(counter, -1); | |
211 | error_init_stride: | |
212 | free_percpu(counter->percpu_counters); | |
213 | error_alloc_percpu: | |
214 | kfree(counter->dimensions); | |
215 | error_dimensions: | |
216 | error_sum_step: | |
217 | kfree(counter); | |
218 | return NULL; | |
219 | } | |
220 | EXPORT_SYMBOL_GPL(lttng_counter_create); | |
221 | ||
222 | void lttng_counter_destroy(struct lib_counter *counter) | |
223 | { | |
224 | struct lib_counter_config *config = &counter->config; | |
225 | int cpu; | |
226 | ||
227 | if (config->alloc & COUNTER_ALLOC_PER_CPU) { | |
228 | for (cpu = 0; cpu < num_possible_cpus(); cpu++) | |
229 | lttng_counter_layout_fini(counter, cpu); | |
230 | free_percpu(counter->percpu_counters); | |
231 | } | |
232 | if (config->alloc & COUNTER_ALLOC_GLOBAL) | |
233 | lttng_counter_layout_fini(counter, -1); | |
234 | kfree(counter->dimensions); | |
235 | kfree(counter); | |
236 | } | |
237 | EXPORT_SYMBOL_GPL(lttng_counter_destroy); | |
238 | ||
239 | int lttng_counter_read(const struct lib_counter_config *config, | |
240 | struct lib_counter *counter, | |
241 | const size_t *dimension_indexes, | |
242 | int cpu, int64_t *value, bool *overflow, | |
243 | bool *underflow) | |
244 | { | |
245 | struct lib_counter_layout *layout; | |
246 | size_t index; | |
247 | ||
248 | if (unlikely(lttng_counter_validate_indexes(config, counter, dimension_indexes))) | |
249 | return -EOVERFLOW; | |
250 | index = lttng_counter_get_index(config, counter, dimension_indexes); | |
251 | ||
252 | switch (config->alloc) { | |
253 | case COUNTER_ALLOC_PER_CPU: | |
254 | if (cpu < 0 || cpu >= num_possible_cpus()) | |
255 | return -EINVAL; | |
256 | layout = per_cpu_ptr(counter->percpu_counters, cpu); | |
257 | break; | |
258 | case COUNTER_ALLOC_PER_CPU | COUNTER_ALLOC_GLOBAL: | |
259 | if (cpu >= 0) { | |
260 | if (cpu >= num_possible_cpus()) | |
261 | return -EINVAL; | |
262 | layout = per_cpu_ptr(counter->percpu_counters, cpu); | |
263 | } else { | |
264 | layout = &counter->global_counters; | |
265 | } | |
266 | break; | |
267 | case COUNTER_ALLOC_GLOBAL: | |
268 | if (cpu >= 0) | |
269 | return -EINVAL; | |
270 | layout = &counter->global_counters; | |
271 | break; | |
272 | default: | |
273 | return -EINVAL; | |
274 | } | |
275 | ||
276 | switch (config->counter_size) { | |
277 | case COUNTER_SIZE_8_BIT: | |
278 | { | |
279 | int8_t *int_p = (int8_t *) layout->counters + index; | |
280 | *value = (int64_t) READ_ONCE(*int_p); | |
281 | break; | |
282 | } | |
283 | case COUNTER_SIZE_16_BIT: | |
284 | { | |
285 | int16_t *int_p = (int16_t *) layout->counters + index; | |
286 | *value = (int64_t) READ_ONCE(*int_p); | |
287 | break; | |
288 | } | |
289 | case COUNTER_SIZE_32_BIT: | |
290 | { | |
291 | int32_t *int_p = (int32_t *) layout->counters + index; | |
292 | *value = (int64_t) READ_ONCE(*int_p); | |
293 | break; | |
294 | } | |
295 | #if BITS_PER_LONG == 64 | |
296 | case COUNTER_SIZE_64_BIT: | |
297 | { | |
298 | int64_t *int_p = (int64_t *) layout->counters + index; | |
299 | *value = READ_ONCE(*int_p); | |
300 | break; | |
301 | } | |
302 | #endif | |
303 | default: | |
304 | WARN_ON_ONCE(1); | |
305 | } | |
306 | *overflow = test_bit(index, layout->overflow_bitmap); | |
307 | *underflow = test_bit(index, layout->underflow_bitmap); | |
308 | return 0; | |
309 | } | |
310 | EXPORT_SYMBOL_GPL(lttng_counter_read); | |
311 | ||
312 | int lttng_counter_aggregate(const struct lib_counter_config *config, | |
313 | struct lib_counter *counter, | |
314 | const size_t *dimension_indexes, | |
315 | int64_t *value, bool *overflow, | |
316 | bool *underflow) | |
317 | { | |
318 | int cpu, ret; | |
319 | int64_t v, sum = 0; | |
320 | bool of, uf; | |
321 | ||
322 | *overflow = false; | |
323 | *underflow = false; | |
324 | ||
325 | switch (config->alloc) { | |
326 | case COUNTER_ALLOC_GLOBAL: /* Fallthrough */ | |
327 | case COUNTER_ALLOC_PER_CPU | COUNTER_ALLOC_GLOBAL: | |
328 | /* Read global counter. */ | |
329 | ret = lttng_counter_read(config, counter, dimension_indexes, | |
330 | -1, &v, &of, &uf); | |
331 | if (ret < 0) | |
332 | return ret; | |
333 | sum += v; | |
334 | *overflow |= of; | |
335 | *underflow |= uf; | |
336 | break; | |
337 | case COUNTER_ALLOC_PER_CPU: | |
338 | break; | |
339 | } | |
340 | ||
341 | switch (config->alloc) { | |
342 | case COUNTER_ALLOC_GLOBAL: | |
343 | break; | |
344 | case COUNTER_ALLOC_PER_CPU | COUNTER_ALLOC_GLOBAL: /* Fallthrough */ | |
345 | case COUNTER_ALLOC_PER_CPU: | |
346 | //TODO: integrate with CPU hotplug and online cpus | |
347 | for (cpu = 0; cpu < num_possible_cpus(); cpu++) { | |
348 | int64_t old = sum; | |
349 | ||
350 | ret = lttng_counter_read(config, counter, dimension_indexes, | |
351 | cpu, &v, &of, &uf); | |
352 | if (ret < 0) | |
353 | return ret; | |
354 | *overflow |= of; | |
355 | *underflow |= uf; | |
356 | /* Overflow is defined on unsigned types. */ | |
357 | sum = (int64_t) ((uint64_t) old + (uint64_t) v); | |
358 | if (v > 0 && sum < old) | |
359 | *overflow = true; | |
360 | else if (v < 0 && sum > old) | |
361 | *underflow = true; | |
362 | } | |
363 | break; | |
364 | default: | |
365 | return -EINVAL; | |
366 | } | |
367 | *value = sum; | |
368 | return 0; | |
369 | } | |
370 | EXPORT_SYMBOL_GPL(lttng_counter_aggregate); | |
371 | ||
372 | static | |
373 | int lttng_counter_clear_cpu(const struct lib_counter_config *config, | |
374 | struct lib_counter *counter, | |
375 | const size_t *dimension_indexes, | |
376 | int cpu) | |
377 | { | |
378 | struct lib_counter_layout *layout; | |
379 | size_t index; | |
380 | ||
381 | if (unlikely(lttng_counter_validate_indexes(config, counter, dimension_indexes))) | |
382 | return -EOVERFLOW; | |
383 | index = lttng_counter_get_index(config, counter, dimension_indexes); | |
384 | ||
385 | switch (config->alloc) { | |
386 | case COUNTER_ALLOC_PER_CPU: | |
387 | if (cpu < 0 || cpu >= num_possible_cpus()) | |
388 | return -EINVAL; | |
389 | layout = per_cpu_ptr(counter->percpu_counters, cpu); | |
390 | break; | |
391 | case COUNTER_ALLOC_PER_CPU | COUNTER_ALLOC_GLOBAL: | |
392 | if (cpu >= 0) { | |
393 | if (cpu >= num_possible_cpus()) | |
394 | return -EINVAL; | |
395 | layout = per_cpu_ptr(counter->percpu_counters, cpu); | |
396 | } else { | |
397 | layout = &counter->global_counters; | |
398 | } | |
399 | break; | |
400 | case COUNTER_ALLOC_GLOBAL: | |
401 | if (cpu >= 0) | |
402 | return -EINVAL; | |
403 | layout = &counter->global_counters; | |
404 | break; | |
405 | default: | |
406 | return -EINVAL; | |
407 | } | |
408 | switch (config->counter_size) { | |
409 | case COUNTER_SIZE_8_BIT: | |
410 | { | |
411 | int8_t *int_p = (int8_t *) layout->counters + index; | |
412 | WRITE_ONCE(*int_p, 0); | |
413 | break; | |
414 | } | |
415 | case COUNTER_SIZE_16_BIT: | |
416 | { | |
417 | int16_t *int_p = (int16_t *) layout->counters + index; | |
418 | WRITE_ONCE(*int_p, 0); | |
419 | break; | |
420 | } | |
421 | case COUNTER_SIZE_32_BIT: | |
422 | { | |
423 | int32_t *int_p = (int32_t *) layout->counters + index; | |
424 | WRITE_ONCE(*int_p, 0); | |
425 | break; | |
426 | } | |
427 | #if BITS_PER_LONG == 64 | |
428 | case COUNTER_SIZE_64_BIT: | |
429 | { | |
430 | int64_t *int_p = (int64_t *) layout->counters + index; | |
431 | WRITE_ONCE(*int_p, 0); | |
432 | break; | |
433 | } | |
434 | #endif | |
435 | default: | |
436 | WARN_ON_ONCE(1); | |
437 | } | |
438 | clear_bit(index, layout->overflow_bitmap); | |
439 | clear_bit(index, layout->underflow_bitmap); | |
440 | return 0; | |
441 | } | |
442 | ||
443 | int lttng_counter_clear(const struct lib_counter_config *config, | |
444 | struct lib_counter *counter, | |
445 | const size_t *dimension_indexes) | |
446 | { | |
447 | int cpu, ret; | |
448 | ||
449 | switch (config->alloc) { | |
450 | case COUNTER_ALLOC_GLOBAL: /* Fallthrough */ | |
451 | case COUNTER_ALLOC_PER_CPU | COUNTER_ALLOC_GLOBAL: | |
452 | /* Clear global counter. */ | |
453 | ret = lttng_counter_clear_cpu(config, counter, dimension_indexes, -1); | |
454 | if (ret < 0) | |
455 | return ret; | |
456 | break; | |
457 | case COUNTER_ALLOC_PER_CPU: | |
458 | break; | |
459 | } | |
460 | ||
461 | switch (config->alloc) { | |
462 | case COUNTER_ALLOC_GLOBAL: | |
463 | break; | |
464 | case COUNTER_ALLOC_PER_CPU | COUNTER_ALLOC_GLOBAL: /* Fallthrough */ | |
465 | case COUNTER_ALLOC_PER_CPU: | |
466 | //TODO: integrate with CPU hotplug and online cpus | |
467 | for (cpu = 0; cpu < num_possible_cpus(); cpu++) { | |
468 | ret = lttng_counter_clear_cpu(config, counter, dimension_indexes, cpu); | |
469 | if (ret < 0) | |
470 | return ret; | |
471 | } | |
472 | break; | |
473 | default: | |
474 | return -EINVAL; | |
475 | } | |
476 | return 0; | |
477 | } | |
478 | EXPORT_SYMBOL_GPL(lttng_counter_clear); | |
479 | ||
480 | int lttng_counter_get_nr_dimensions(const struct lib_counter_config *config, | |
481 | struct lib_counter *counter, | |
482 | size_t *nr_dimensions) | |
483 | { | |
484 | *nr_dimensions = counter->nr_dimensions; | |
485 | return 0; | |
486 | } | |
487 | EXPORT_SYMBOL_GPL(lttng_counter_get_nr_dimensions); | |
488 | ||
489 | int lttng_counter_get_max_nr_elem(const struct lib_counter_config *config, | |
490 | struct lib_counter *counter, | |
491 | size_t *max_nr_elem) /* array of size nr_dimensions */ | |
492 | { | |
493 | size_t dimension; | |
494 | ||
495 | for (dimension = 0; dimension < counter->nr_dimensions; dimension++) | |
496 | max_nr_elem[dimension] = lttng_counter_get_dimension_nr_elements(&counter->dimensions[dimension]); | |
497 | return 0; | |
498 | } | |
499 | EXPORT_SYMBOL_GPL(lttng_counter_get_max_nr_elem); | |
500 | ||
501 | MODULE_LICENSE("GPL and additional rights"); | |
502 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); | |
503 | MODULE_DESCRIPTION("LTTng counter library"); | |
504 | MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." | |
505 | __stringify(LTTNG_MODULES_MINOR_VERSION) "." | |
506 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION) | |
507 | LTTNG_MODULES_EXTRAVERSION); |