src/lib/lttng-ust/lttng-counter-client-percpu-32-modular.c

   1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
   2  *
   3  * lttng-counter-client-percpu-32-modular.c
   4  *
   5  * LTTng lib counter client. Per-cpu 32-bit counters in modular
   6  * arithmetic.
   7  *
   8  * Copyright (C) 2020 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   9  */
  10
  11 #include "lib/lttng-ust/events.h"
  12 #include "common/counter/counter.h"
  13 #include "common/counter/counter-api.h"
  14 #include "lttng-tracer-core.h"
  15 #include "lttng-counter-client.h"
  16
  17 static const struct lib_counter_config client_config = {
  18         .alloc = COUNTER_ALLOC_PER_CPU,
  19         .sync = COUNTER_SYNC_PER_CPU,
  20         .arithmetic = COUNTER_ARITHMETIC_MODULAR,
  21         .counter_size = COUNTER_SIZE_32_BIT,
  22 };
  23
  24 static struct lib_counter *counter_create(size_t nr_dimensions,
  25                                           const struct lttng_counter_dimension *dimensions,
  26                                           int64_t global_sum_step,
  27                                           int global_counter_fd,
  28                                           int nr_counter_cpu_fds,
  29                                           const int *counter_cpu_fds,
  30                                           bool is_daemon)
  31 {
  32         size_t max_nr_elem[LTTNG_COUNTER_DIMENSION_MAX], i;
  33
  34         if (nr_dimensions > LTTNG_COUNTER_DIMENSION_MAX)
  35                 return NULL;
  36         for (i = 0; i < nr_dimensions; i++) {
  37                 if (dimensions[i].has_underflow || dimensions[i].has_overflow)
  38                         return NULL;
  39                 max_nr_elem[i] = dimensions[i].size;
  40         }
  41         return lttng_counter_create(&client_config, nr_dimensions, max_nr_elem,
  42                                     global_sum_step, global_counter_fd, nr_counter_cpu_fds,
  43                                     counter_cpu_fds, is_daemon);
  44 }
  45
  46 static void counter_destroy(struct lib_counter *counter)
  47 {
  48         lttng_counter_destroy(counter);
  49 }
  50
  51 static int counter_add(struct lib_counter *counter, const size_t *dimension_indexes, int64_t v)
  52 {
  53         return lttng_counter_add(&client_config, counter, dimension_indexes, v);
  54 }
  55
  56 static int counter_read(struct lib_counter *counter, const size_t *dimension_indexes, int cpu,
  57                         int64_t *value, bool *overflow, bool *underflow)
  58 {
  59         return lttng_counter_read(&client_config, counter, dimension_indexes, cpu, value,
  60                                   overflow, underflow);
  61 }
  62
  63 static int counter_aggregate(struct lib_counter *counter, const size_t *dimension_indexes,
  64                              int64_t *value, bool *overflow, bool *underflow)
  65 {
  66         return lttng_counter_aggregate(&client_config, counter, dimension_indexes, value,
  67                                        overflow, underflow);
  68 }
  69
  70 static int counter_clear(struct lib_counter *counter, const size_t *dimension_indexes)
  71 {
  72         return lttng_counter_clear(&client_config, counter, dimension_indexes);
  73 }
  74
  75 static struct lttng_counter_transport lttng_counter_transport = {
  76         .name = "counter-per-cpu-32-modular",
  77         .ops = {
  78                 .counter_create = counter_create,
  79                 .counter_destroy = counter_destroy,
  80                 .counter_add = counter_add,
  81                 .counter_read = counter_read,
  82                 .counter_aggregate = counter_aggregate,
  83                 .counter_clear = counter_clear,
  84         },
  85         .client_config = &client_config,
  86 };
  87
  88 void lttng_counter_client_percpu_32_modular_init(void)
  89 {
  90         lttng_counter_transport_register(&lttng_counter_transport);
  91 }
  92
  93 void lttng_counter_client_percpu_32_modular_exit(void)
  94 {
  95         lttng_counter_transport_unregister(&lttng_counter_transport);
  96 }