liblttng-ust/lttng-counter-client-percpu-64-modular.c

   1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
   2  *
   3  * lttng-counter-client-percpu-64-modular.c
   4  *
   5  * LTTng lib counter client. Per-cpu 64-bit counters in modular
   6  * arithmetic.
   7  *
   8  * Copyright (C) 2020 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   9  */
  10
  11 #include <lttng/ust-events.h>
  12 #include "../libcounter/counter.h"
  13 #include "../libcounter/counter-api.h"
  14 #include "lttng-tracer-core.h"
  15
  16 static const struct lib_counter_config client_config = {
  17         .alloc = COUNTER_ALLOC_PER_CPU,
  18         .sync = COUNTER_SYNC_PER_CPU,
  19         .arithmetic = COUNTER_ARITHMETIC_MODULAR,
  20         .counter_size = COUNTER_SIZE_64_BIT,
  21 };
  22
  23 static struct lib_counter *counter_create(size_t nr_dimensions,
  24                                           const struct lttng_counter_dimension *dimensions,
  25                                           int64_t global_sum_step,
  26                                           int global_counter_fd,
  27                                           int nr_counter_cpu_fds,
  28                                           const int *counter_cpu_fds,
  29                                           bool is_daemon)
  30 {
  31         size_t max_nr_elem[LTTNG_COUNTER_DIMENSION_MAX], i;
  32
  33         if (nr_dimensions > LTTNG_COUNTER_DIMENSION_MAX)
  34                 return NULL;
  35         for (i = 0; i < nr_dimensions; i++) {
  36                 if (dimensions[i].has_underflow || dimensions[i].has_overflow)
  37                         return NULL;
  38                 max_nr_elem[i] = dimensions[i].size;
  39         }
  40         return lttng_counter_create(&client_config, nr_dimensions, max_nr_elem,
  41                                     global_sum_step, global_counter_fd, nr_counter_cpu_fds,
  42                                     counter_cpu_fds, is_daemon);
  43 }
  44
  45 static void counter_destroy(struct lib_counter *counter)
  46 {
  47         lttng_counter_destroy(counter);
  48 }
  49
  50 static int counter_add(struct lib_counter *counter, const size_t *dimension_indexes, int64_t v)
  51 {
  52         return lttng_counter_add(&client_config, counter, dimension_indexes, v);
  53 }
  54
  55 static int counter_read(struct lib_counter *counter, const size_t *dimension_indexes, int cpu,
  56                         int64_t *value, bool *overflow, bool *underflow)
  57 {
  58         return lttng_counter_read(&client_config, counter, dimension_indexes, cpu, value,
  59                                   overflow, underflow);
  60 }
  61
  62 static int counter_aggregate(struct lib_counter *counter, const size_t *dimension_indexes,
  63                              int64_t *value, bool *overflow, bool *underflow)
  64 {
  65         return lttng_counter_aggregate(&client_config, counter, dimension_indexes, value,
  66                                        overflow, underflow);
  67 }
  68
  69 static int counter_clear(struct lib_counter *counter, const size_t *dimension_indexes)
  70 {
  71         return lttng_counter_clear(&client_config, counter, dimension_indexes);
  72 }
  73
  74 static struct lttng_counter_transport lttng_counter_transport = {
  75         .name = "counter-per-cpu-64-modular",
  76         .ops = {
  77                 .counter_create = counter_create,
  78                 .counter_destroy = counter_destroy,
  79                 .counter_add = counter_add,
  80                 .counter_read = counter_read,
  81                 .counter_aggregate = counter_aggregate,
  82                 .counter_clear = counter_clear,
  83         },
  84         .client_config = &client_config,
  85 };
  86
  87 void lttng_counter_client_percpu_64_modular_init(void)
  88 {
  89         lttng_counter_transport_register(&lttng_counter_transport);
  90 }
  91
  92 void lttng_counter_client_percpu_64_modular_exit(void)
  93 {
  94         lttng_counter_transport_unregister(&lttng_counter_transport);
  95 }