LLVM OpenMP* Runtime Library
kmp_utility.cpp
1 /*
2  * kmp_utility.cpp -- Utility routines for the OpenMP support library.
3  */
4 
5 //===----------------------------------------------------------------------===//
6 //
7 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
8 // See https://llvm.org/LICENSE.txt for license information.
9 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "kmp.h"
14 #include "kmp_i18n.h"
15 #include "kmp_str.h"
16 #include "kmp_wrapper_getpid.h"
17 #include <float.h>
18 
19 static const char *unknown = "unknown";
20 
21 #if KMP_ARCH_X86 || KMP_ARCH_X86_64
22 
23 /* NOTE: If called before serial_initialize (i.e. from runtime_initialize), then
24  the debugging package has not been initialized yet, and only "0" will print
25  debugging output since the environment variables have not been read. */
26 
27 #ifdef KMP_DEBUG
28 static int trace_level = 5;
29 #endif
30 
31 /* LOG_ID_BITS = ( 1 + floor( log_2( max( log_per_phy - 1, 1 ))))
32  * APIC_ID = (PHY_ID << LOG_ID_BITS) | LOG_ID
33  * PHY_ID = APIC_ID >> LOG_ID_BITS
34  */
35 int __kmp_get_physical_id(int log_per_phy, int apic_id) {
36  int index_lsb, index_msb, temp;
37 
38  if (log_per_phy > 1) {
39  index_lsb = 0;
40  index_msb = 31;
41 
42  temp = log_per_phy;
43  while ((temp & 1) == 0) {
44  temp >>= 1;
45  index_lsb++;
46  }
47 
48  temp = log_per_phy;
49  while ((temp & 0x80000000) == 0) {
50  temp <<= 1;
51  index_msb--;
52  }
53 
54  /* If >1 bits were set in log_per_phy, choose next higher power of 2 */
55  if (index_lsb != index_msb)
56  index_msb++;
57 
58  return ((int)(apic_id >> index_msb));
59  }
60 
61  return apic_id;
62 }
63 
64 /*
65  * LOG_ID_BITS = ( 1 + floor( log_2( max( log_per_phy - 1, 1 ))))
66  * APIC_ID = (PHY_ID << LOG_ID_BITS) | LOG_ID
67  * LOG_ID = APIC_ID & (( 1 << LOG_ID_BITS ) - 1 )
68  */
69 int __kmp_get_logical_id(int log_per_phy, int apic_id) {
70  unsigned current_bit;
71  int bits_seen;
72 
73  if (log_per_phy <= 1)
74  return (0);
75 
76  bits_seen = 0;
77 
78  for (current_bit = 1; log_per_phy != 0; current_bit <<= 1) {
79  if (log_per_phy & current_bit) {
80  log_per_phy &= ~current_bit;
81  bits_seen++;
82  }
83  }
84 
85  /* If exactly 1 bit was set in log_per_phy, choose next lower power of 2 */
86  if (bits_seen == 1) {
87  current_bit >>= 1;
88  }
89 
90  return ((int)((current_bit - 1) & apic_id));
91 }
92 
93 static kmp_uint64 __kmp_parse_frequency( // R: Frequency in Hz.
94  char const *frequency // I: Float number and unit: MHz, GHz, or TGz.
95 ) {
96 
97  double value = 0.0;
98  char *unit = NULL;
99  kmp_uint64 result = 0; /* Zero is a better unknown value than all ones. */
100 
101  if (frequency == NULL) {
102  return result;
103  }
104  value = strtod(frequency, &unit);
105  if (0 < value &&
106  value <= DBL_MAX) { // Good value (not overflow, underflow, etc).
107  if (strcmp(unit, "MHz") == 0) {
108  value = value * 1.0E+6;
109  } else if (strcmp(unit, "GHz") == 0) {
110  value = value * 1.0E+9;
111  } else if (strcmp(unit, "THz") == 0) {
112  value = value * 1.0E+12;
113  } else { // Wrong unit.
114  return result;
115  }
116  result = (kmp_uint64)value; // rounds down
117  }
118  return result;
119 
120 } // func __kmp_parse_cpu_frequency
121 
122 void __kmp_query_cpuid(kmp_cpuinfo_t *p) {
123  struct kmp_cpuid buf;
124  int max_arg;
125  int log_per_phy;
126 #ifdef KMP_DEBUG
127  int cflush_size;
128 #endif
129 
130  p->initialized = 1;
131 
132  p->flags.sse2 = 1; // Assume SSE2 by default.
133 
134  __kmp_x86_cpuid(0, 0, &buf);
135 
136  KA_TRACE(trace_level,
137  ("INFO: CPUID %d: EAX=0x%08X EBX=0x%08X ECX=0x%08X EDX=0x%08X\n", 0,
138  buf.eax, buf.ebx, buf.ecx, buf.edx));
139 
140  max_arg = buf.eax;
141 
142  p->apic_id = -1;
143 
144  if (max_arg >= 1) {
145  int i;
146  kmp_uint32 t, data[4];
147 
148  __kmp_x86_cpuid(1, 0, &buf);
149  KA_TRACE(trace_level,
150  ("INFO: CPUID %d: EAX=0x%08X EBX=0x%08X ECX=0x%08X EDX=0x%08X\n",
151  1, buf.eax, buf.ebx, buf.ecx, buf.edx));
152 
153  {
154 #define get_value(reg, lo, mask) (((reg) >> (lo)) & (mask))
155 
156  p->signature = buf.eax;
157  p->family = get_value(buf.eax, 20, 0xff) + get_value(buf.eax, 8, 0x0f);
158  p->model =
159  (get_value(buf.eax, 16, 0x0f) << 4) + get_value(buf.eax, 4, 0x0f);
160  p->stepping = get_value(buf.eax, 0, 0x0f);
161 
162 #undef get_value
163 
164  KA_TRACE(trace_level, (" family = %d, model = %d, stepping = %d\n",
165  p->family, p->model, p->stepping));
166  }
167 
168  for (t = buf.ebx, i = 0; i < 4; t >>= 8, ++i) {
169  data[i] = (t & 0xff);
170  }
171 
172  p->flags.sse2 = (buf.edx >> 26) & 1;
173 
174 #ifdef KMP_DEBUG
175 
176  if ((buf.edx >> 4) & 1) {
177  /* TSC - Timestamp Counter Available */
178  KA_TRACE(trace_level, (" TSC"));
179  }
180  if ((buf.edx >> 8) & 1) {
181  /* CX8 - CMPXCHG8B Instruction Available */
182  KA_TRACE(trace_level, (" CX8"));
183  }
184  if ((buf.edx >> 9) & 1) {
185  /* APIC - Local APIC Present (multi-processor operation support */
186  KA_TRACE(trace_level, (" APIC"));
187  }
188  if ((buf.edx >> 15) & 1) {
189  /* CMOV - Conditional MOVe Instruction Available */
190  KA_TRACE(trace_level, (" CMOV"));
191  }
192  if ((buf.edx >> 18) & 1) {
193  /* PSN - Processor Serial Number Available */
194  KA_TRACE(trace_level, (" PSN"));
195  }
196  if ((buf.edx >> 19) & 1) {
197  /* CLFLUSH - Cache Flush Instruction Available */
198  cflush_size =
199  data[1] * 8; /* Bits 15-08: CLFLUSH line size = 8 (64 bytes) */
200  KA_TRACE(trace_level, (" CLFLUSH(%db)", cflush_size));
201  }
202  if ((buf.edx >> 21) & 1) {
203  /* DTES - Debug Trace & EMON Store */
204  KA_TRACE(trace_level, (" DTES"));
205  }
206  if ((buf.edx >> 22) & 1) {
207  /* ACPI - ACPI Support Available */
208  KA_TRACE(trace_level, (" ACPI"));
209  }
210  if ((buf.edx >> 23) & 1) {
211  /* MMX - Multimedia Extensions */
212  KA_TRACE(trace_level, (" MMX"));
213  }
214  if ((buf.edx >> 25) & 1) {
215  /* SSE - SSE Instructions */
216  KA_TRACE(trace_level, (" SSE"));
217  }
218  if ((buf.edx >> 26) & 1) {
219  /* SSE2 - SSE2 Instructions */
220  KA_TRACE(trace_level, (" SSE2"));
221  }
222  if ((buf.edx >> 27) & 1) {
223  /* SLFSNP - Self-Snooping Cache */
224  KA_TRACE(trace_level, (" SLFSNP"));
225  }
226 #endif /* KMP_DEBUG */
227 
228  if ((buf.edx >> 28) & 1) {
229  /* Bits 23-16: Logical Processors per Physical Processor (1 for P4) */
230  log_per_phy = data[2];
231  p->apic_id = data[3]; /* Bits 31-24: Processor Initial APIC ID (X) */
232  KA_TRACE(trace_level, (" HT(%d TPUs)", log_per_phy));
233  p->physical_id = __kmp_get_physical_id(log_per_phy, p->apic_id);
234  p->logical_id = __kmp_get_logical_id(log_per_phy, p->apic_id);
235  }
236 #ifdef KMP_DEBUG
237  if ((buf.edx >> 29) & 1) {
238  /* ATHROTL - Automatic Throttle Control */
239  KA_TRACE(trace_level, (" ATHROTL"));
240  }
241  KA_TRACE(trace_level, (" ]\n"));
242 
243  for (i = 2; i <= max_arg; ++i) {
244  __kmp_x86_cpuid(i, 0, &buf);
245  KA_TRACE(trace_level,
246  ("INFO: CPUID %d: EAX=0x%08X EBX=0x%08X ECX=0x%08X EDX=0x%08X\n",
247  i, buf.eax, buf.ebx, buf.ecx, buf.edx));
248  }
249 #endif
250  p->flags.rtm = 0;
251  p->flags.hybrid = 0;
252  if (max_arg > 7) {
253  /* RTM bit CPUID.07:EBX, bit 11 */
254  /* HYRBID bit CPUID.07:EDX, bit 15 */
255  __kmp_x86_cpuid(7, 0, &buf);
256  p->flags.rtm = (buf.ebx >> 11) & 1;
257  p->flags.hybrid = (buf.edx >> 15) & 1;
258  if (p->flags.rtm) {
259  KA_TRACE(trace_level, (" RTM"));
260  }
261  if (p->flags.hybrid) {
262  KA_TRACE(trace_level, (" HYBRID"));
263  }
264  }
265  }
266 
267  { // Parse CPU brand string for frequency, saving the string for later.
268  int i;
269  kmp_cpuid_t *base = (kmp_cpuid_t *)&p->name[0];
270 
271  // Get CPU brand string.
272  for (i = 0; i < 3; ++i) {
273  __kmp_x86_cpuid(0x80000002 + i, 0, base + i);
274  }
275  p->name[sizeof(p->name) - 1] = 0; // Just in case. ;-)
276  KA_TRACE(trace_level, ("cpu brand string: \"%s\"\n", &p->name[0]));
277 
278  // Parse frequency.
279  p->frequency = __kmp_parse_frequency(strrchr(&p->name[0], ' '));
280  KA_TRACE(trace_level,
281  ("cpu frequency from brand string: %" KMP_UINT64_SPEC "\n",
282  p->frequency));
283  }
284 }
285 
286 #endif /* KMP_ARCH_X86 || KMP_ARCH_X86_64 */
287 
288 void __kmp_expand_host_name(char *buffer, size_t size) {
289  KMP_DEBUG_ASSERT(size >= sizeof(unknown));
290 #if KMP_OS_WINDOWS
291  {
292  DWORD s = size;
293 
294  if (!GetComputerNameA(buffer, &s))
295  KMP_STRCPY_S(buffer, size, unknown);
296  }
297 #else
298  buffer[size - 2] = 0;
299  if (gethostname(buffer, size) || buffer[size - 2] != 0)
300  KMP_STRCPY_S(buffer, size, unknown);
301 #endif
302 }
303 
304 /* Expand the meta characters in the filename:
305  * Currently defined characters are:
306  * %H the hostname
307  * %P the number of threads used.
308  * %I the unique identifier for this run.
309  */
310 
311 void __kmp_expand_file_name(char *result, size_t rlen, char *pattern) {
312  char *pos = result, *end = result + rlen - 1;
313  char buffer[256];
314  int default_cpu_width = 1;
315  int snp_result;
316 
317  KMP_DEBUG_ASSERT(rlen > 0);
318  *end = 0;
319  {
320  int i;
321  for (i = __kmp_xproc; i >= 10; i /= 10, ++default_cpu_width)
322  ;
323  }
324 
325  if (pattern != NULL) {
326  while (*pattern != '\0' && pos < end) {
327  if (*pattern != '%') {
328  *pos++ = *pattern++;
329  } else {
330  char *old_pattern = pattern;
331  int width = 1;
332  int cpu_width = default_cpu_width;
333 
334  ++pattern;
335 
336  if (*pattern >= '0' && *pattern <= '9') {
337  width = 0;
338  do {
339  width = (width * 10) + *pattern++ - '0';
340  } while (*pattern >= '0' && *pattern <= '9');
341  if (width < 0 || width > 1024)
342  width = 1;
343 
344  cpu_width = width;
345  }
346 
347  switch (*pattern) {
348  case 'H':
349  case 'h': {
350  __kmp_expand_host_name(buffer, sizeof(buffer));
351  KMP_STRNCPY(pos, buffer, end - pos + 1);
352  if (*end == 0) {
353  while (*pos)
354  ++pos;
355  ++pattern;
356  } else
357  pos = end;
358  } break;
359  case 'P':
360  case 'p': {
361  snp_result = KMP_SNPRINTF(pos, end - pos + 1, "%0*d", cpu_width,
362  __kmp_dflt_team_nth);
363  if (snp_result >= 0 && snp_result <= end - pos) {
364  while (*pos)
365  ++pos;
366  ++pattern;
367  } else
368  pos = end;
369  } break;
370  case 'I':
371  case 'i': {
372  pid_t id = getpid();
373 #if KMP_ARCH_X86_64 && defined(__MINGW32__)
374  snp_result = KMP_SNPRINTF(pos, end - pos + 1, "%0*lld", width, id);
375 #else
376  snp_result = KMP_SNPRINTF(pos, end - pos + 1, "%0*d", width, id);
377 #endif
378  if (snp_result >= 0 && snp_result <= end - pos) {
379  while (*pos)
380  ++pos;
381  ++pattern;
382  } else
383  pos = end;
384  break;
385  }
386  case '%': {
387  *pos++ = '%';
388  ++pattern;
389  break;
390  }
391  default: {
392  *pos++ = '%';
393  pattern = old_pattern + 1;
394  break;
395  }
396  }
397  }
398  }
399  /* TODO: How do we get rid of this? */
400  if (*pattern != '\0')
401  KMP_FATAL(FileNameTooLong);
402  }
403 
404  *pos = '\0';
405 }