FD.io VPP  v18.07.1-19-g511ce25
Vector Packet Processing
clib.h
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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  Copyright (c) 2001, 2002, 2003 Eliot Dresselhaus
17 
18  Permission is hereby granted, free of charge, to any person obtaining
19  a copy of this software and associated documentation files (the
20  "Software"), to deal in the Software without restriction, including
21  without limitation the rights to use, copy, modify, merge, publish,
22  distribute, sublicense, and/or sell copies of the Software, and to
23  permit persons to whom the Software is furnished to do so, subject to
24  the following conditions:
25 
26  The above copyright notice and this permission notice shall be
27  included in all copies or substantial portions of the Software.
28 
29  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
30  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
31  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
32  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
33  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
34  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
35  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
36 */
37 
38 #ifndef included_clib_h
39 #define included_clib_h
40 
41 /* Standalone means to not assume we are running on a Unix box. */
42 #if ! defined (CLIB_STANDALONE) && ! defined (CLIB_LINUX_KERNEL)
43 #define CLIB_UNIX
44 #endif
45 
46 #include <vppinfra/types.h>
47 
48 /* Global DEBUG flag. Setting this to 1 or 0 turns off
49  ASSERT (see vppinfra/error.h) & other debugging code. */
50 #ifndef CLIB_DEBUG
51 #define CLIB_DEBUG 0
52 #endif
53 
54 #ifndef NULL
55 #define NULL ((void *) 0)
56 #endif
57 
58 #define BITS(x) (8*sizeof(x))
59 #define ARRAY_LEN(x) (sizeof (x)/sizeof (x[0]))
60 
61 #define _STRUCT_FIELD(t,f) (((t *) 0)->f)
62 #define STRUCT_OFFSET_OF(t,f) ((uword) & _STRUCT_FIELD (t, f))
63 #define STRUCT_BIT_OFFSET_OF(t,f) (BITS(u8) * (uword) & _STRUCT_FIELD (t, f))
64 #define STRUCT_SIZE_OF(t,f) (sizeof (_STRUCT_FIELD (t, f)))
65 #define STRUCT_BITS_OF(t,f) (BITS (_STRUCT_FIELD (t, f)))
66 #define STRUCT_ARRAY_LEN(t,f) ARRAY_LEN (_STRUCT_FIELD (t, f))
67 #define STRUCT_MARK(mark) u8 mark[0]
68 #define STRUCT_MARK_PTR(v, f) &(v)->f
69 
70 /* Stride in bytes between struct array elements. */
71 #define STRUCT_STRIDE_OF(t,f) \
72  ( ((uword) & (((t *) 0)[1].f)) \
73  - ((uword) & (((t *) 0)[0].f)))
74 
75 #define STRUCT_OFFSET_OF_VAR(v,f) ((uword) (&(v)->f) - (uword) (v))
76 
77 /* Used to pack structure elements. */
78 #define CLIB_PACKED(x) x __attribute__ ((packed))
79 #define CLIB_UNUSED(x) x __attribute__ ((unused))
80 
81 /* Make a string from the macro's argument */
82 #define CLIB_STRING_MACRO(x) #x
83 
84 #define __clib_unused __attribute__ ((unused))
85 #define __clib_weak __attribute__ ((weak))
86 #define __clib_packed __attribute__ ((packed))
87 #define __clib_constructor __attribute__ ((constructor))
88 
89 #define never_inline __attribute__ ((__noinline__))
90 
91 #if CLIB_DEBUG > 0
92 #define always_inline static inline
93 #define static_always_inline static inline
94 #else
95 #define always_inline static inline __attribute__ ((__always_inline__))
96 #define static_always_inline static inline __attribute__ ((__always_inline__))
97 #endif
98 
99 
100 /* Reserved (unused) structure element with address offset between
101  from and to. */
102 #define CLIB_PAD_FROM_TO(from,to) u8 pad_##from[(to) - (from)]
103 
104 /* Hints to compiler about hot/cold code. */
105 #define PREDICT_FALSE(x) __builtin_expect((x),0)
106 #define PREDICT_TRUE(x) __builtin_expect((x),1)
107 
108 /* Full memory barrier (read and write). */
109 #define CLIB_MEMORY_BARRIER() __sync_synchronize ()
110 
111 #if __x86_64__
112 #define CLIB_MEMORY_STORE_BARRIER() __builtin_ia32_sfence ()
113 #else
114 #define CLIB_MEMORY_STORE_BARRIER() __sync_synchronize ()
115 #endif
116 
117 /* Arranges for function to be called before main. */
118 #define INIT_FUNCTION(decl) \
119  decl __attribute ((constructor)); \
120  decl
121 
122 /* Arranges for function to be called before exit. */
123 #define EXIT_FUNCTION(decl) \
124  decl __attribute ((destructor)); \
125  decl
126 
127 /* Use __builtin_clz if available. */
128 #if uword_bits == 64
129 #define count_leading_zeros(x) __builtin_clzll (x)
130 #define count_trailing_zeros(x) __builtin_ctzll (x)
131 #else
132 #define count_leading_zeros(x) __builtin_clzl (x)
133 #define count_trailing_zeros(x) __builtin_ctzl (x)
134 #endif
135 
136 #if defined (count_leading_zeros)
139 {
140  uword n;
141  n = count_leading_zeros (x);
142  return BITS (uword) - n - 1;
143 }
144 #else
146 min_log2 (uword x)
147 {
148  uword a = x, b = BITS (uword) / 2, c = 0, r = 0;
149 
150  /* Reduce x to 4 bit result. */
151 #define _ \
152 { \
153  c = a >> b; \
154  if (c) a = c; \
155  if (c) r += b; \
156  b /= 2; \
157 }
158 
159  if (BITS (uword) > 32)
160  _;
161  _;
162  _;
163  _;
164 #undef _
165 
166  /* Do table lookup on 4 bit partial. */
167  if (BITS (uword) > 32)
168  {
169  const u64 table = 0x3333333322221104LL;
170  uword t = (table >> (4 * a)) & 0xf;
171  r = t < 4 ? r + t : ~0;
172  }
173  else
174  {
175  const u32 table = 0x22221104;
176  uword t = (a & 8) ? 3 : ((table >> (4 * a)) & 0xf);
177  r = t < 4 ? r + t : ~0;
178  }
179 
180  return r;
181 }
182 #endif
183 
186 {
187  uword l = min_log2 (x);
188  if (x > ((uword) 1 << l))
189  l++;
190  return l;
191 }
192 
195 {
196  if (BITS (uword) == 64)
197  return min_log2 (x);
198  else
199  {
200  uword l, y;
201  y = x;
202  l = 0;
203  if (y == 0)
204  {
205  l += 32;
206  x >>= 32;
207  }
208  l += min_log2 (x);
209  return l;
210  }
211 }
212 
215 {
216  return ((uword) 1 << x) - (uword) 1;
217 }
218 
221 {
222  word y = (word) 1 << min_log2 (x);
223  if (x > y)
224  y *= 2;
225  return y;
226 }
227 
230 {
231  return 0 == (x & (x - 1));
232 }
233 
236 {
237  return (x + pow2 - 1) & ~(pow2 - 1);
238 }
239 
242 {
243  return (x + pow2 - 1) & ~(pow2 - 1);
244 }
245 
248 {
249  return x & -x;
250 }
251 
254 {
255  uword result;
256 #ifdef count_trailing_zeros
257  result = count_trailing_zeros (x);
258 #else
259  result = min_log2 (first_set (x));
260 #endif
261  return result;
262 }
263 
266 {
267  return (int) x;
268 }
269 
272 {
273  return (word) (x + .5);
274 }
275 
278 {
279  return f * flt_round_nearest (x / f);
280 }
281 
282 #define clib_max(x,y) \
283 ({ \
284  __typeof__ (x) _x = (x); \
285  __typeof__ (y) _y = (y); \
286  _x > _y ? _x : _y; \
287 })
288 
289 #define clib_min(x,y) \
290 ({ \
291  __typeof__ (x) _x = (x); \
292  __typeof__ (y) _y = (y); \
293  _x < _y ? _x : _y; \
294 })
295 
296 #define clib_abs(x) \
297 ({ \
298  __typeof__ (x) _x = (x); \
299  _x < 0 ? -_x : _x; \
300 })
301 
302 /* Standard standalone-only function declarations. */
303 #ifndef CLIB_UNIX
304 void clib_standalone_init (void *memory, uword memory_bytes);
305 
306 void qsort (void *base, uword n, uword size,
307  int (*)(const void *, const void *));
308 #endif
309 
310 /* Stack backtrace. */
311 uword
312 clib_backtrace (uword * callers, uword max_callers, uword n_frames_to_skip);
313 
314 #endif /* included_clib_h */
315 
316 /*
317  * fd.io coding-style-patch-verification: ON
318  *
319  * Local Variables:
320  * eval: (c-set-style "gnu")
321  * End:
322  */
vhost_user_memory_t memory
Definition: vhost_user.h:117
a
Definition: bitmap.h:538
static uword log2_first_set(uword x)
Definition: clib.h:253
#define count_leading_zeros(x)
Definition: clib.h:132
unsigned long u64
Definition: types.h:89
#define count_trailing_zeros(x)
Definition: clib.h:133
static uword min_log2(uword x)
Definition: clib.h:138
double f64
Definition: types.h:142
i64 word
Definition: types.h:111
#define always_inline
Definition: clib.h:92
static uword pow2_mask(uword x)
Definition: clib.h:214
unsigned int u32
Definition: types.h:88
static u64 min_log2_u64(u64 x)
Definition: clib.h:194
uword clib_backtrace(uword *callers, uword max_callers, uword n_frames_to_skip)
Definition: backtrace.c:226
svmdb_client_t * c
static f64 flt_round_to_multiple(f64 x, f64 f)
Definition: clib.h:277
static uword max_pow2(uword x)
Definition: clib.h:220
static u64 round_pow2_u64(u64 x, u64 pow2)
Definition: clib.h:241
static uword round_pow2(uword x, uword pow2)
Definition: clib.h:235
static uword first_set(uword x)
Definition: clib.h:247
static uword is_pow2(uword x)
Definition: clib.h:229
static word flt_round_nearest(f64 x)
Definition: clib.h:271
void qsort(void *base, uword n, uword size, int(*compar)(const void *, const void *))
Definition: qsort.c:56
static uword max_log2(uword x)
Definition: clib.h:185
u64 uword
Definition: types.h:112
static f64 flt_round_down(f64 x)
Definition: clib.h:265
#define BITS(x)
Definition: clib.h:58