FD.io VPP  v20.01-45-g7a071e370
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 #include <vppinfra/atomics.h>
50 
51 /* Global DEBUG flag. Setting this to 1 or 0 turns off
52  ASSERT (see vppinfra/error.h) & other debugging code. */
53 #ifndef CLIB_DEBUG
54 #define CLIB_DEBUG 0
55 #endif
56 
57 #ifndef NULL
58 #define NULL ((void *) 0)
59 #endif
60 
61 #define BITS(x) (8*sizeof(x))
62 #define ARRAY_LEN(x) (sizeof (x)/sizeof (x[0]))
63 
64 #define _STRUCT_FIELD(t,f) (((t *) 0)->f)
65 #define STRUCT_OFFSET_OF(t,f) ((uword) & _STRUCT_FIELD (t, f))
66 #define STRUCT_BIT_OFFSET_OF(t,f) (BITS(u8) * (uword) & _STRUCT_FIELD (t, f))
67 #define STRUCT_SIZE_OF(t,f) (sizeof (_STRUCT_FIELD (t, f)))
68 #define STRUCT_BITS_OF(t,f) (BITS (_STRUCT_FIELD (t, f)))
69 #define STRUCT_ARRAY_LEN(t,f) ARRAY_LEN (_STRUCT_FIELD (t, f))
70 #define STRUCT_MARK(mark) u8 mark[0]
71 #define STRUCT_MARK_PTR(v, f) &(v)->f
72 
73 /* Stride in bytes between struct array elements. */
74 #define STRUCT_STRIDE_OF(t,f) \
75  ( ((uword) & (((t *) 0)[1].f)) \
76  - ((uword) & (((t *) 0)[0].f)))
77 
78 #define STRUCT_OFFSET_OF_VAR(v,f) ((uword) (&(v)->f) - (uword) (v))
79 
80 /* Used to pack structure elements. */
81 #define CLIB_PACKED(x) x __attribute__ ((packed))
82 #define CLIB_UNUSED(x) x __attribute__ ((unused))
83 
84 /* similar to CLIB_CACHE_LINE_ALIGN_MARK() but with arbitrary alignment */
85 #define CLIB_ALIGN_MARK(name, alignment) u8 name[0] __attribute__((aligned(alignment)))
86 
87 /* Make a string from the macro's argument */
88 #define CLIB_STRING_MACRO(x) #x
89 
90 #define __clib_unused __attribute__ ((unused))
91 #define __clib_weak __attribute__ ((weak))
92 #define __clib_packed __attribute__ ((packed))
93 #define __clib_constructor __attribute__ ((constructor))
94 
95 #define never_inline __attribute__ ((__noinline__))
96 
97 #if CLIB_DEBUG > 0
98 #define always_inline static inline
99 #define static_always_inline static inline
100 #else
101 #define always_inline static inline __attribute__ ((__always_inline__))
102 #define static_always_inline static inline __attribute__ ((__always_inline__))
103 #endif
104 
105 
106 /* Reserved (unused) structure element with address offset between
107  from and to. */
108 #define CLIB_PAD_FROM_TO(from,to) u8 pad_##from[(to) - (from)]
109 
110 /* Hints to compiler about hot/cold code. */
111 #define PREDICT_FALSE(x) __builtin_expect((x),0)
112 #define PREDICT_TRUE(x) __builtin_expect((x),1)
113 
114 /* Full memory barrier (read and write). */
115 #define CLIB_MEMORY_BARRIER() __sync_synchronize ()
116 
117 #if __x86_64__
118 #define CLIB_MEMORY_STORE_BARRIER() __builtin_ia32_sfence ()
119 #else
120 #define CLIB_MEMORY_STORE_BARRIER() __sync_synchronize ()
121 #endif
122 
123 /* Arranges for function to be called before main. */
124 #define INIT_FUNCTION(decl) \
125  decl __attribute ((constructor)); \
126  decl
127 
128 /* Arranges for function to be called before exit. */
129 #define EXIT_FUNCTION(decl) \
130  decl __attribute ((destructor)); \
131  decl
132 
133 /* Use __builtin_clz if available. */
134 #if uword_bits == 64
135 #define count_leading_zeros(x) __builtin_clzll (x)
136 #define count_trailing_zeros(x) __builtin_ctzll (x)
137 #else
138 #define count_leading_zeros(x) __builtin_clzl (x)
139 #define count_trailing_zeros(x) __builtin_ctzl (x)
140 #endif
141 
142 #if defined (count_leading_zeros)
145 {
146  uword n;
147  n = count_leading_zeros (x);
148  return BITS (uword) - n - 1;
149 }
150 #else
152 min_log2 (uword x)
153 {
154  uword a = x, b = BITS (uword) / 2, c = 0, r = 0;
155 
156  /* Reduce x to 4 bit result. */
157 #define _ \
158 { \
159  c = a >> b; \
160  if (c) a = c; \
161  if (c) r += b; \
162  b /= 2; \
163 }
164 
165  if (BITS (uword) > 32)
166  _;
167  _;
168  _;
169  _;
170 #undef _
171 
172  /* Do table lookup on 4 bit partial. */
173  if (BITS (uword) > 32)
174  {
175  const u64 table = 0x3333333322221104LL;
176  uword t = (table >> (4 * a)) & 0xf;
177  r = t < 4 ? r + t : ~0;
178  }
179  else
180  {
181  const u32 table = 0x22221104;
182  uword t = (a & 8) ? 3 : ((table >> (4 * a)) & 0xf);
183  r = t < 4 ? r + t : ~0;
184  }
185 
186  return r;
187 }
188 #endif
189 
192 {
193  uword l = min_log2 (x);
194  if (x > ((uword) 1 << l))
195  l++;
196  return l;
197 }
198 
201 {
202  if (BITS (uword) == 64)
203  return min_log2 (x);
204  else
205  {
206  uword l, y;
207  y = x;
208  l = 0;
209  if (y == 0)
210  {
211  l += 32;
212  x >>= 32;
213  }
214  l += min_log2 (x);
215  return l;
216  }
217 }
218 
221 {
222  return ((uword) 1 << x) - (uword) 1;
223 }
224 
227 {
228  word y = (word) 1 << min_log2 (x);
229  if (x > y)
230  y *= 2;
231  return y;
232 }
233 
236 {
237  return 0 == (x & (x - 1));
238 }
239 
242 {
243  return (x + pow2 - 1) & ~(pow2 - 1);
244 }
245 
248 {
249  return (x + pow2 - 1) & ~(pow2 - 1);
250 }
251 
254 {
255  return x & -x;
256 }
257 
260 {
261  uword result;
262 #ifdef count_trailing_zeros
263  result = count_trailing_zeros (x);
264 #else
265  result = min_log2 (first_set (x));
266 #endif
267  return result;
268 }
269 
272 {
273  return (int) x;
274 }
275 
278 {
279  return (word) (x + .5);
280 }
281 
284 {
285  return f * flt_round_nearest (x / f);
286 }
287 
288 #define clib_max(x,y) \
289 ({ \
290  __typeof__ (x) _x = (x); \
291  __typeof__ (y) _y = (y); \
292  _x > _y ? _x : _y; \
293 })
294 
295 #define clib_min(x,y) \
296 ({ \
297  __typeof__ (x) _x = (x); \
298  __typeof__ (y) _y = (y); \
299  _x < _y ? _x : _y; \
300 })
301 
302 #define clib_abs(x) \
303 ({ \
304  __typeof__ (x) _x = (x); \
305  _x < 0 ? -_x : _x; \
306 })
307 
308 /* Standard standalone-only function declarations. */
309 #ifndef CLIB_UNIX
310 void clib_standalone_init (void *memory, uword memory_bytes);
311 
312 void qsort (void *base, uword n, uword size,
313  int (*)(const void *, const void *));
314 #endif
315 
316 /* Stack backtrace. */
317 uword
318 clib_backtrace (uword * callers, uword max_callers, uword n_frames_to_skip);
319 
320 #endif /* included_clib_h */
321 
322 /*
323  * fd.io coding-style-patch-verification: ON
324  *
325  * Local Variables:
326  * eval: (c-set-style "gnu")
327  * End:
328  */
vhost_user_memory_t memory
Definition: vhost_user.h:148
a
Definition: bitmap.h:538
static uword log2_first_set(uword x)
Definition: clib.h:259
#define count_leading_zeros(x)
Definition: clib.h:138
unsigned long u64
Definition: types.h:89
#define count_trailing_zeros(x)
Definition: clib.h:139
static uword min_log2(uword x)
Definition: clib.h:144
double f64
Definition: types.h:142
i64 word
Definition: types.h:111
#define always_inline
Definition: clib.h:98
static uword pow2_mask(uword x)
Definition: clib.h:220
unsigned int u32
Definition: types.h:88
static u64 min_log2_u64(u64 x)
Definition: clib.h:200
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:283
static uword max_pow2(uword x)
Definition: clib.h:226
static u64 round_pow2_u64(u64 x, u64 pow2)
Definition: clib.h:247
static uword round_pow2(uword x, uword pow2)
Definition: clib.h:241
static uword first_set(uword x)
Definition: clib.h:253
static uword is_pow2(uword x)
Definition: clib.h:235
static word flt_round_nearest(f64 x)
Definition: clib.h:277
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:191
u64 uword
Definition: types.h:112
static f64 flt_round_down(f64 x)
Definition: clib.h:271
#define BITS(x)
Definition: clib.h:61