FD.io VPP  v18.10-34-gcce845e
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 #include <vppinfra/config.h>
42 
43 /* Standalone means to not assume we are running on a Unix box. */
44 #if ! defined (CLIB_STANDALONE) && ! defined (CLIB_LINUX_KERNEL)
45 #define CLIB_UNIX
46 #endif
47 
48 #include <vppinfra/types.h>
49 
50 /* Global DEBUG flag. Setting this to 1 or 0 turns off
51  ASSERT (see vppinfra/error.h) & other debugging code. */
52 #ifndef CLIB_DEBUG
53 #define CLIB_DEBUG 0
54 #endif
55 
56 #ifndef NULL
57 #define NULL ((void *) 0)
58 #endif
59 
60 #define BITS(x) (8*sizeof(x))
61 #define ARRAY_LEN(x) (sizeof (x)/sizeof (x[0]))
62 
63 #define _STRUCT_FIELD(t,f) (((t *) 0)->f)
64 #define STRUCT_OFFSET_OF(t,f) ((uword) & _STRUCT_FIELD (t, f))
65 #define STRUCT_BIT_OFFSET_OF(t,f) (BITS(u8) * (uword) & _STRUCT_FIELD (t, f))
66 #define STRUCT_SIZE_OF(t,f) (sizeof (_STRUCT_FIELD (t, f)))
67 #define STRUCT_BITS_OF(t,f) (BITS (_STRUCT_FIELD (t, f)))
68 #define STRUCT_ARRAY_LEN(t,f) ARRAY_LEN (_STRUCT_FIELD (t, f))
69 #define STRUCT_MARK(mark) u8 mark[0]
70 #define STRUCT_MARK_PTR(v, f) &(v)->f
71 
72 /* Stride in bytes between struct array elements. */
73 #define STRUCT_STRIDE_OF(t,f) \
74  ( ((uword) & (((t *) 0)[1].f)) \
75  - ((uword) & (((t *) 0)[0].f)))
76 
77 #define STRUCT_OFFSET_OF_VAR(v,f) ((uword) (&(v)->f) - (uword) (v))
78 
79 /* Used to pack structure elements. */
80 #define CLIB_PACKED(x) x __attribute__ ((packed))
81 #define CLIB_UNUSED(x) x __attribute__ ((unused))
82 
83 /* Make a string from the macro's argument */
84 #define CLIB_STRING_MACRO(x) #x
85 
86 #define __clib_unused __attribute__ ((unused))
87 #define __clib_weak __attribute__ ((weak))
88 #define __clib_packed __attribute__ ((packed))
89 #define __clib_constructor __attribute__ ((constructor))
90 
91 #define never_inline __attribute__ ((__noinline__))
92 
93 #if CLIB_DEBUG > 0
94 #define always_inline static inline
95 #define static_always_inline static inline
96 #else
97 #define always_inline static inline __attribute__ ((__always_inline__))
98 #define static_always_inline static inline __attribute__ ((__always_inline__))
99 #endif
100 
101 
102 /* Reserved (unused) structure element with address offset between
103  from and to. */
104 #define CLIB_PAD_FROM_TO(from,to) u8 pad_##from[(to) - (from)]
105 
106 /* Hints to compiler about hot/cold code. */
107 #define PREDICT_FALSE(x) __builtin_expect((x),0)
108 #define PREDICT_TRUE(x) __builtin_expect((x),1)
109 
110 /* Full memory barrier (read and write). */
111 #define CLIB_MEMORY_BARRIER() __sync_synchronize ()
112 
113 #if __x86_64__
114 #define CLIB_MEMORY_STORE_BARRIER() __builtin_ia32_sfence ()
115 #else
116 #define CLIB_MEMORY_STORE_BARRIER() __sync_synchronize ()
117 #endif
118 
119 /* Arranges for function to be called before main. */
120 #define INIT_FUNCTION(decl) \
121  decl __attribute ((constructor)); \
122  decl
123 
124 /* Arranges for function to be called before exit. */
125 #define EXIT_FUNCTION(decl) \
126  decl __attribute ((destructor)); \
127  decl
128 
129 /* Use __builtin_clz if available. */
130 #if uword_bits == 64
131 #define count_leading_zeros(x) __builtin_clzll (x)
132 #define count_trailing_zeros(x) __builtin_ctzll (x)
133 #else
134 #define count_leading_zeros(x) __builtin_clzl (x)
135 #define count_trailing_zeros(x) __builtin_ctzl (x)
136 #endif
137 
138 #if defined (count_leading_zeros)
141 {
142  uword n;
143  n = count_leading_zeros (x);
144  return BITS (uword) - n - 1;
145 }
146 #else
148 min_log2 (uword x)
149 {
150  uword a = x, b = BITS (uword) / 2, c = 0, r = 0;
151 
152  /* Reduce x to 4 bit result. */
153 #define _ \
154 { \
155  c = a >> b; \
156  if (c) a = c; \
157  if (c) r += b; \
158  b /= 2; \
159 }
160 
161  if (BITS (uword) > 32)
162  _;
163  _;
164  _;
165  _;
166 #undef _
167 
168  /* Do table lookup on 4 bit partial. */
169  if (BITS (uword) > 32)
170  {
171  const u64 table = 0x3333333322221104LL;
172  uword t = (table >> (4 * a)) & 0xf;
173  r = t < 4 ? r + t : ~0;
174  }
175  else
176  {
177  const u32 table = 0x22221104;
178  uword t = (a & 8) ? 3 : ((table >> (4 * a)) & 0xf);
179  r = t < 4 ? r + t : ~0;
180  }
181 
182  return r;
183 }
184 #endif
185 
188 {
189  uword l = min_log2 (x);
190  if (x > ((uword) 1 << l))
191  l++;
192  return l;
193 }
194 
197 {
198  if (BITS (uword) == 64)
199  return min_log2 (x);
200  else
201  {
202  uword l, y;
203  y = x;
204  l = 0;
205  if (y == 0)
206  {
207  l += 32;
208  x >>= 32;
209  }
210  l += min_log2 (x);
211  return l;
212  }
213 }
214 
217 {
218  return ((uword) 1 << x) - (uword) 1;
219 }
220 
223 {
224  word y = (word) 1 << min_log2 (x);
225  if (x > y)
226  y *= 2;
227  return y;
228 }
229 
232 {
233  return 0 == (x & (x - 1));
234 }
235 
238 {
239  return (x + pow2 - 1) & ~(pow2 - 1);
240 }
241 
244 {
245  return (x + pow2 - 1) & ~(pow2 - 1);
246 }
247 
250 {
251  return x & -x;
252 }
253 
256 {
257  uword result;
258 #ifdef count_trailing_zeros
259  result = count_trailing_zeros (x);
260 #else
261  result = min_log2 (first_set (x));
262 #endif
263  return result;
264 }
265 
268 {
269  return (int) x;
270 }
271 
274 {
275  return (word) (x + .5);
276 }
277 
280 {
281  return f * flt_round_nearest (x / f);
282 }
283 
284 #define clib_max(x,y) \
285 ({ \
286  __typeof__ (x) _x = (x); \
287  __typeof__ (y) _y = (y); \
288  _x > _y ? _x : _y; \
289 })
290 
291 #define clib_min(x,y) \
292 ({ \
293  __typeof__ (x) _x = (x); \
294  __typeof__ (y) _y = (y); \
295  _x < _y ? _x : _y; \
296 })
297 
298 #define clib_abs(x) \
299 ({ \
300  __typeof__ (x) _x = (x); \
301  _x < 0 ? -_x : _x; \
302 })
303 
304 /* Standard standalone-only function declarations. */
305 #ifndef CLIB_UNIX
306 void clib_standalone_init (void *memory, uword memory_bytes);
307 
308 void qsort (void *base, uword n, uword size,
309  int (*)(const void *, const void *));
310 #endif
311 
312 /* Stack backtrace. */
313 uword
314 clib_backtrace (uword * callers, uword max_callers, uword n_frames_to_skip);
315 
316 #endif /* included_clib_h */
317 
318 /*
319  * fd.io coding-style-patch-verification: ON
320  *
321  * Local Variables:
322  * eval: (c-set-style "gnu")
323  * End:
324  */
vhost_user_memory_t memory
Definition: vhost_user.h:122
a
Definition: bitmap.h:538
static uword log2_first_set(uword x)
Definition: clib.h:255
#define count_leading_zeros(x)
Definition: clib.h:134
unsigned long u64
Definition: types.h:89
#define count_trailing_zeros(x)
Definition: clib.h:135
static uword min_log2(uword x)
Definition: clib.h:140
double f64
Definition: types.h:142
i64 word
Definition: types.h:111
#define always_inline
Definition: clib.h:94
static uword pow2_mask(uword x)
Definition: clib.h:216
unsigned int u32
Definition: types.h:88
static u64 min_log2_u64(u64 x)
Definition: clib.h:196
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:279
static uword max_pow2(uword x)
Definition: clib.h:222
static u64 round_pow2_u64(u64 x, u64 pow2)
Definition: clib.h:243
static uword round_pow2(uword x, uword pow2)
Definition: clib.h:237
static uword first_set(uword x)
Definition: clib.h:249
static uword is_pow2(uword x)
Definition: clib.h:231
static word flt_round_nearest(f64 x)
Definition: clib.h:273
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:187
u64 uword
Definition: types.h:112
static f64 flt_round_down(f64 x)
Definition: clib.h:267
#define BITS(x)
Definition: clib.h:60