src/lib/lttng-ust/lttng-context-ip.c

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-only
   3  *
   4  * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  *
   6  * LTTng UST Instruction Pointer Context.
   7  */
   8
   9 #define _LGPL_SOURCE
  10 #include <limits.h>
  11 #include <stddef.h>
  12 #include <sys/types.h>
  13 #include <unistd.h>
  14 #include <lttng/ust-events.h>
  15 #include <lttng/ust-tracer.h>
  16 #include <lttng/ust-ringbuffer-context.h>
  17
  18 #include "context-internal.h"
  19
  20 static
  21 size_t ip_get_size(void *priv __attribute__((unused)),
  22                 struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)),
  23                 size_t offset)
  24 {
  25         size_t size = 0;
  26
  27         size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(void *));
  28         size += sizeof(void *);
  29         return size;
  30 }
  31
  32 static
  33 void ip_record(void *priv __attribute__((unused)),
  34                 struct lttng_ust_probe_ctx *probe_ctx,
  35                 struct lttng_ust_ring_buffer_ctx *ctx,
  36                 struct lttng_ust_channel_buffer *chan)
  37 {
  38         void *ip;
  39
  40         ip = probe_ctx->ip;
  41         chan->ops->event_write(ctx, &ip, sizeof(ip), lttng_ust_rb_alignof(ip));
  42 }
  43
  44 static
  45 void ip_get_value(void *priv __attribute__((unused)),
  46                 struct lttng_ust_probe_ctx *probe_ctx,
  47                 struct lttng_ust_ctx_value *value)
  48 {
  49         value->u.u64 = (unsigned long) probe_ctx->ip;
  50 }
  51
  52 static const struct lttng_ust_ctx_field *ctx_field = lttng_ust_static_ctx_field(
  53         lttng_ust_static_event_field("ip",
  54                 lttng_ust_static_type_integer(sizeof(void *) * CHAR_BIT,
  55                                 lttng_ust_rb_alignof(void *) * CHAR_BIT,
  56                                 lttng_ust_is_signed_type(void *),
  57                                 LTTNG_UST_BYTE_ORDER, 10),
  58                 false, false),
  59         ip_get_size,
  60         ip_record,
  61         ip_get_value,
  62         NULL, NULL);
  63
  64 int lttng_add_ip_to_ctx(struct lttng_ust_ctx **ctx)
  65 {
  66         int ret;
  67
  68         if (lttng_find_context(*ctx, ctx_field->event_field->name)) {
  69                 ret = -EEXIST;
  70                 goto error_find_context;
  71         }
  72         ret = lttng_ust_context_append(ctx, ctx_field);
  73         if (ret)
  74                 return ret;
  75         return 0;
  76
  77 error_find_context:
  78         return ret;
  79 }