FD.io VPP  v19.01.3-6-g70449b9b9
Vector Packet Processing
trace_funcs.h
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2015 Cisco and/or its affiliates.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at:
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 /*
16  * trace_funcs.h: VLIB trace buffer.
17  *
18  * Copyright (c) 2008 Eliot Dresselhaus
19  *
20  * Permission is hereby granted, free of charge, to any person obtaining
21  * a copy of this software and associated documentation files (the
22  * "Software"), to deal in the Software without restriction, including
23  * without limitation the rights to use, copy, modify, merge, publish,
24  * distribute, sublicense, and/or sell copies of the Software, and to
25  * permit persons to whom the Software is furnished to do so, subject to
26  * the following conditions:
27  *
28  * The above copyright notice and this permission notice shall be
29  * included in all copies or substantial portions of the Software.
30  *
31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
38  */
39 
40 #ifndef included_vlib_trace_funcs_h
41 #define included_vlib_trace_funcs_h
42 
43 extern u8 *vnet_trace_dummy;
44 
45 always_inline void
47 {
48  /*
49  * this assert seems right, but goes off constantly.
50  * disabling it appears to make the pain go away
51  */
52  ASSERT (1 || b->flags & VLIB_BUFFER_IS_TRACED);
54 }
55 
56 always_inline void *
58  vlib_node_runtime_t * r, vlib_buffer_t * b, u32 n_data_bytes)
59 {
60  vlib_trace_main_t *tm = &vm->trace_main;
62  u32 n_data_words;
63 
65 
66  if (PREDICT_FALSE (tm->trace_enable == 0))
67  {
68  ASSERT (vec_len (vnet_trace_dummy) >= n_data_bytes + sizeof (*h));
69  return vnet_trace_dummy;
70  }
71 
72  vlib_validate_trace (tm, b);
73 
74  n_data_bytes = round_pow2 (n_data_bytes, sizeof (h[0]));
75  n_data_words = n_data_bytes / sizeof (h[0]);
77  1 + n_data_words, sizeof (h[0]));
78 
80  h->n_data = n_data_words;
81  h->node_index = r->node_index;
82 
83  return h->data;
84 }
85 
88 {
89  return h + 1 + h->n_data;
90 }
91 
92 always_inline void
94 {
95  vlib_trace_main_t *tm = &vm->trace_main;
96  vlib_validate_trace (tm, b);
97  _vec_len (tm->trace_buffer_pool[b->trace_index]) = 0;
99 }
100 
101 always_inline void
103  vlib_node_runtime_t * r, u32 next_index)
104 {
105  vlib_next_frame_t *nf;
106  nf = vlib_node_runtime_get_next_frame (vm, r, next_index);
107  nf->flags |= VLIB_FRAME_TRACE;
108 }
109 
110 void trace_apply_filter (vlib_main_t * vm);
111 
112 /* Mark buffer as traced and allocate trace buffer. */
113 always_inline void
116  u32 next_index, vlib_buffer_t * b, int follow_chain)
117 {
118  vlib_trace_main_t *tm = &vm->trace_main;
120 
121  if (PREDICT_FALSE (tm->trace_enable == 0))
122  return;
123 
124  /*
125  * Apply filter to existing traces to keep number of allocated traces low.
126  * Performed each time around the main loop.
127  */
128  if (tm->last_main_loop_count != vm->main_loop_count)
129  {
131  trace_apply_filter (vm);
132  }
133 
134  vlib_trace_next_frame (vm, r, next_index);
135 
136  pool_get (tm->trace_buffer_pool, h);
137 
138  do
139  {
140  b->flags |= VLIB_BUFFER_IS_TRACED;
141  b->trace_index = h - tm->trace_buffer_pool;
142  }
143  while (follow_chain && (b = vlib_get_next_buffer (vm, b)));
144 }
145 
146 always_inline void
148  u32 bi_target)
149 {
150  vlib_buffer_t *b_target = vlib_get_buffer (vm, bi_target);
151  b_target->flags |= b->flags & VLIB_BUFFER_IS_TRACED;
152  b_target->trace_index = b->trace_index;
153 }
154 
157 {
158  vlib_trace_main_t *tm = &vm->trace_main;
159  vlib_trace_node_t *tn;
160  int n;
161 
162  if (rt->node_index >= vec_len (tm->nodes))
163  return 0;
164  tn = tm->nodes + rt->node_index;
165  n = tn->limit - tn->count;
166  ASSERT (n >= 0);
167 
168  return n;
169 }
170 
171 always_inline void
173 {
174  vlib_trace_main_t *tm = &vm->trace_main;
176 
177  ASSERT (count <= tn->limit);
178  tn->count = tn->limit - count;
179 }
180 
181 /* Helper function for nodes which only trace buffer data. */
182 void
184  vlib_node_runtime_t * node,
185  u32 * buffers,
186  uword n_buffers,
187  uword next_buffer_stride,
188  uword n_buffer_data_bytes_in_trace);
189 
190 #endif /* included_vlib_trace_funcs_h */
191 
192 /*
193  * fd.io coding-style-patch-verification: ON
194  *
195  * Local Variables:
196  * eval: (c-set-style "gnu")
197  * End:
198  */
void vlib_trace_frame_buffers_only(vlib_main_t *vm, vlib_node_runtime_t *node, u32 *buffers, uword n_buffers, uword next_buffer_stride, uword n_buffer_data_bytes_in_trace)
Definition: trace.c:47
static u32 vlib_get_trace_count(vlib_main_t *vm, vlib_node_runtime_t *rt)
Definition: trace_funcs.h:156
vlib_trace_node_t * nodes
Definition: trace.h:86
static vlib_trace_header_t * vlib_trace_header_next(vlib_trace_header_t *h)
Definition: trace_funcs.h:87
#define vec_add2_aligned(V, P, N, A)
Add N elements to end of vector V, return pointer to new elements in P.
Definition: vec.h:576
#define pool_get(P, E)
Allocate an object E from a pool P (unspecified alignment).
Definition: pool.h:236
unsigned char u8
Definition: types.h:56
static void vlib_trace_buffer(vlib_main_t *vm, vlib_node_runtime_t *r, u32 next_index, vlib_buffer_t *b, int follow_chain)
Definition: trace_funcs.h:114
vlib_trace_header_t ** trace_buffer_pool
Definition: trace.h:72
u32 last_main_loop_count
Definition: trace.h:74
u32 trace_enable
Definition: trace.h:83
#define always_inline
Definition: clib.h:98
u8 * vnet_trace_dummy
Definition: trace.c:43
#define vec_elt_at_index(v, i)
Get vector value at index i checking that i is in bounds.
static void vlib_trace_next_frame(vlib_main_t *vm, vlib_node_runtime_t *r, u32 next_index)
Definition: trace_funcs.h:102
unsigned int u32
Definition: types.h:88
static vlib_next_frame_t * vlib_node_runtime_get_next_frame(vlib_main_t *vm, vlib_node_runtime_t *n, u32 next_index)
Definition: node_funcs.h:264
static void vlib_free_trace(vlib_main_t *vm, vlib_buffer_t *b)
Definition: trace_funcs.h:93
#define PREDICT_FALSE(x)
Definition: clib.h:111
u32 node_index
Node index.
Definition: node.h:518
static void vlib_buffer_copy_trace_flag(vlib_main_t *vm, vlib_buffer_t *b, u32 bi_target)
Definition: trace_funcs.h:147
void trace_apply_filter(vlib_main_t *vm)
Definition: trace.c:226
static vlib_buffer_t * vlib_get_next_buffer(vlib_main_t *vm, vlib_buffer_t *b)
Get next buffer in buffer linklist, or zero for end of list.
Definition: buffer_funcs.h:251
#define pool_is_free_index(P, I)
Use free bitmap to query whether given index is free.
Definition: pool.h:283
static uword round_pow2(uword x, uword pow2)
Definition: clib.h:241
#define pool_put_index(p, i)
Free pool element with given index.
Definition: pool.h:311
#define ASSERT(truth)
vlib_trace_main_t trace_main
Definition: main.h:135
size_t count
Definition: vapi.c:47
static void * vlib_add_trace(vlib_main_t *vm, vlib_node_runtime_t *r, vlib_buffer_t *b, u32 n_data_bytes)
Definition: trace_funcs.h:57
#define vec_len(v)
Number of elements in vector (rvalue-only, NULL tolerant)
u64 uword
Definition: types.h:112
#define VLIB_FRAME_TRACE
Definition: node.h:458
static void vlib_validate_trace(vlib_trace_main_t *tm, vlib_buffer_t *b)
Definition: trace_funcs.h:46
static void vlib_set_trace_count(vlib_main_t *vm, vlib_node_runtime_t *rt, u32 count)
Definition: trace_funcs.h:172
u32 flags
buffer flags: VLIB_BUFFER_FREE_LIST_INDEX_MASK: bits used to store free list index, VLIB_BUFFER_IS_TRACED: trace this buffer.
Definition: buffer.h:117
u32 main_loop_count
Definition: main.h:77
static vlib_buffer_t * vlib_get_buffer(vlib_main_t *vm, u32 buffer_index)
Translate buffer index into buffer pointer.
Definition: buffer_funcs.h:62
u32 trace_index
Specifies index into trace buffer if VLIB_PACKET_IS_TRACED flag is set.
Definition: buffer.h:151
u64 cpu_time_last_node_dispatch
Definition: main.h:71