liblttng-ust/lttng-context-pthread-id.c

   1 /*
   2  * (C) Copyright        2009-2011 -
   3  *              Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *
   5  * LTTng UST pthread_id context.
   6  *
   7  * Dual LGPL v2.1/GPL v2 license.
   8  */
   9
  10 #include <pthread.h>
  11 #include <lttng/ust-events.h>
  12 #include <lttng/ust-tracer.h>
  13 #include <lttng/ringbuffer-config.h>
  14
  15 static
  16 size_t pthread_id_get_size(size_t offset)
  17 {
  18         size_t size = 0;
  19
  20         size += lib_ring_buffer_align(offset, lttng_alignof(unsigned long));
  21         size += sizeof(unsigned long);
  22         return size;
  23 }
  24
  25 static
  26 void pthread_id_record(struct lttng_ctx_field *field,
  27                  struct lttng_ust_lib_ring_buffer_ctx *ctx,
  28                  struct ltt_channel *chan)
  29 {
  30         unsigned long pthread_id;
  31
  32         pthread_id = (unsigned long) pthread_self();
  33         lib_ring_buffer_align_ctx(ctx, lttng_alignof(pthread_id));
  34         chan->ops->event_write(ctx, &pthread_id, sizeof(pthread_id));
  35 }
  36
  37 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx)
  38 {
  39         struct lttng_ctx_field *field;
  40
  41         field = lttng_append_context(ctx);
  42         if (!field)
  43                 return -ENOMEM;
  44         if (lttng_find_context(*ctx, "pthread_id")) {
  45                 lttng_remove_context_field(ctx, field);
  46                 return -EEXIST;
  47         }
  48         field->event_field.name = "pthread_id";
  49         field->event_field.type.atype = atype_integer;
  50         field->event_field.type.u.basic.integer.size = sizeof(unsigned long) * CHAR_BIT;
  51         field->event_field.type.u.basic.integer.alignment = lttng_alignof(unsigned long) * CHAR_BIT;
  52         field->event_field.type.u.basic.integer.signedness = lttng_is_signed_type(unsigned long);
  53         field->event_field.type.u.basic.integer.reverse_byte_order = 0;
  54         field->event_field.type.u.basic.integer.base = 10;
  55         field->event_field.type.u.basic.integer.encoding = lttng_encode_none;
  56         field->get_size = pthread_id_get_size;
  57         field->record = pthread_id_record;
  58         return 0;
  59 }