1/*--------------------------------------------------------------------*/
2/*--- Cachegrind: cache configuration.                   cg-arch.c ---*/
3/*--------------------------------------------------------------------*/
4
5/*
6   This file is part of Cachegrind, a Valgrind tool for cache
7   profiling programs.
8
9   Copyright (C) 2011-2013 Nicholas Nethercote
10      njn@valgrind.org
11
12   This program is free software; you can redistribute it and/or
13   modify it under the terms of the GNU General Public License as
14   published by the Free Software Foundation; either version 2 of the
15   License, or (at your option) any later version.
16
17   This program is distributed in the hope that it will be useful, but
18   WITHOUT ANY WARRANTY; without even the implied warranty of
19   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20   General Public License for more details.
21
22   You should have received a copy of the GNU General Public License
23   along with this program; if not, write to the Free Software
24   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
25   02111-1307, USA.
26
27   The GNU General Public License is contained in the file COPYING.
28*/
29
30#include "pub_tool_basics.h"
31#include "pub_tool_libcassert.h"
32#include "pub_tool_libcbase.h"
33#include "pub_tool_libcprint.h"
34#include "pub_tool_options.h"
35#include "pub_tool_machine.h"
36
37#include "cg_arch.h"
38
39static void configure_caches(cache_t* I1c, cache_t* D1c, cache_t* LLc,
40                             Bool all_caches_clo_defined);
41
42// Checks cache config is ok.  Returns NULL if ok, or a pointer to an error
43// string otherwise.
44static const HChar* check_cache(cache_t* cache)
45{
46   // Simulator requires set count to be a power of two.
47   if ((cache->size % (cache->line_size * cache->assoc) != 0) ||
48       (-1 == VG_(log2)(cache->size/cache->line_size/cache->assoc)))
49   {
50      return "Cache set count is not a power of two.\n";
51   }
52
53   // Simulator requires line size to be a power of two.
54   if (-1 == VG_(log2)(cache->line_size)) {
55      return "Cache line size is not a power of two.\n";
56   }
57
58   // Then check line size >= 16 -- any smaller and a single instruction could
59   // straddle three cache lines, which breaks a simulation assertion and is
60   // stupid anyway.
61   if (cache->line_size < MIN_LINE_SIZE) {
62      return "Cache line size is too small.\n";
63   }
64
65   /* Then check cache size > line size (causes seg faults if not). */
66   if (cache->size <= cache->line_size) {
67      return "Cache size <= line size.\n";
68   }
69
70   /* Then check assoc <= (size / line size) (seg faults otherwise). */
71   if (cache->assoc > (cache->size / cache->line_size)) {
72      return "Cache associativity > (size / line size).\n";
73   }
74
75   return NULL;
76}
77
78
79static void parse_cache_opt ( cache_t* cache, const HChar* opt,
80                              const HChar* optval )
81{
82   Long i1, i2, i3;
83   HChar* endptr;
84   const HChar* checkRes;
85
86   // Option argument looks like "65536,2,64".  Extract them.
87   i1 = VG_(strtoll10)(optval,   &endptr); if (*endptr != ',')  goto bad;
88   i2 = VG_(strtoll10)(endptr+1, &endptr); if (*endptr != ',')  goto bad;
89   i3 = VG_(strtoll10)(endptr+1, &endptr); if (*endptr != '\0') goto bad;
90
91   // Check for overflow.
92   cache->size      = (Int)i1;
93   cache->assoc     = (Int)i2;
94   cache->line_size = (Int)i3;
95   if (cache->size      != i1) goto overflow;
96   if (cache->assoc     != i2) goto overflow;
97   if (cache->line_size != i3) goto overflow;
98
99   checkRes = check_cache(cache);
100   if (checkRes) {
101      VG_(fmsg)("%s", checkRes);
102      goto bad;
103   }
104
105   return;
106
107  bad:
108   VG_(fmsg_bad_option)(opt, "");
109
110  overflow:
111   VG_(fmsg_bad_option)(opt,
112      "One of the cache parameters was too large and overflowed.\n");
113}
114
115
116Bool VG_(str_clo_cache_opt)(const HChar *arg,
117                            cache_t* clo_I1c,
118                            cache_t* clo_D1c,
119                            cache_t* clo_LLc)
120{
121   const HChar* tmp_str;
122
123   if      VG_STR_CLO(arg, "--I1", tmp_str) {
124      parse_cache_opt(clo_I1c, arg, tmp_str);
125      return True;
126   } else if VG_STR_CLO(arg, "--D1", tmp_str) {
127      parse_cache_opt(clo_D1c, arg, tmp_str);
128      return True;
129   } else if (VG_STR_CLO(arg, "--L2", tmp_str) || // for backwards compatibility
130              VG_STR_CLO(arg, "--LL", tmp_str)) {
131      parse_cache_opt(clo_LLc, arg, tmp_str);
132      return True;
133   } else
134      return False;
135}
136
137static void umsg_cache_img(const HChar* desc, cache_t* c)
138{
139   VG_(umsg)("  %s: %'d B, %d-way, %d B lines\n", desc,
140             c->size, c->assoc, c->line_size);
141}
142
143// Verifies if c is a valid cache.
144// An invalid value causes an assert, unless clo_redefined is True.
145static void check_cache_or_override(const HChar* desc, cache_t* c, Bool clo_redefined)
146{
147   const HChar* checkRes;
148
149   checkRes = check_cache(c);
150   if (checkRes) {
151      VG_(umsg)("Auto-detected %s cache configuration not supported: %s",
152                desc, checkRes);
153      umsg_cache_img(desc, c);
154      if (!clo_redefined) {
155         VG_(umsg)("As it probably should be supported, please report a bug!\n");
156         VG_(umsg)("Bypass this message by using option --%s=...\n", desc);
157         tl_assert(0);
158      }
159   }
160}
161
162
163/* If the LL cache config isn't something the simulation functions
164   can handle, try to adjust it so it is.  Caches are characterised
165   by (total size T, line size L, associativity A), and then we
166   have
167
168     number of sets S = T / (L * A)
169
170   The required constraints are:
171
172   * L must be a power of 2, but it always is in practice, so
173     no problem there
174
175   * A can be any value >= 1
176
177   * T can be any value, but ..
178
179   * S must be a power of 2.
180
181   That sometimes gives a problem.  For example, some Core iX based
182   Intel CPUs have T = 12MB, A = 16, L = 64, which gives 12288
183   sets.  The "fix" in this case is to increase the associativity
184   by 50% to 24, which reduces the number of sets to 8192, making
185   it a power of 2.  That's what the following code does (handing
186   the "3/2 rescaling case".)  We might need to deal with other
187   ratios later (5/4 ?).
188
189   The "fix" is "justified" (cough, cough) by alleging that
190   increases of associativity above about 4 have very little effect
191   on the actual miss rate.  It would be far more inaccurate to
192   fudge this by changing the size of the simulated cache --
193   changing the associativity is a much better option.
194*/
195
196static void
197maybe_tweak_LLc(cache_t *LLc)
198{
199  if (LLc->size > 0 && LLc->assoc > 0 && LLc->line_size > 0) {
200      Long nSets = (Long)LLc->size / (Long)(LLc->line_size * LLc->assoc);
201      if (/* stay sane */
202          nSets >= 4
203          /* nSets is not a power of 2 */
204          && VG_(log2_64)( (ULong)nSets ) == -1
205          /* nSets is 50% above a power of 2 */
206          && VG_(log2_64)( (ULong)((2 * nSets) / (Long)3) ) != -1
207          /* associativity can be increased by exactly 50% */
208          && (LLc->assoc % 2) == 0
209         ) {
210         /* # sets is 1.5 * a power of two, but the associativity is
211            even, so we can increase that up by 50% and implicitly
212            scale the # sets down accordingly. */
213         Int new_assoc = LLc->assoc + (LLc->assoc / 2);
214         VG_(dmsg)("warning: pretending that LL cache has associativity"
215                   " %d instead of actual %d\n", new_assoc, LLc->assoc);
216         LLc->assoc = new_assoc;
217      }
218   }
219}
220
221void VG_(post_clo_init_configure_caches)(cache_t* I1c,
222                                         cache_t* D1c,
223                                         cache_t* LLc,
224                                         cache_t* clo_I1c,
225                                         cache_t* clo_D1c,
226                                         cache_t* clo_LLc)
227{
228#define DEFINED(L)   (-1 != L->size  || -1 != L->assoc || -1 != L->line_size)
229
230   // Count how many were defined on the command line.
231   Bool all_caches_clo_defined =
232      (DEFINED(clo_I1c) &&
233       DEFINED(clo_D1c) &&
234       DEFINED(clo_LLc));
235
236   // Set the cache config (using auto-detection, if supported by the
237   // architecture).
238   configure_caches( I1c, D1c, LLc, all_caches_clo_defined );
239
240   maybe_tweak_LLc( LLc );
241
242   // Check the default/auto-detected values.
243   // Allow the user to override invalid auto-detected caches
244   // with command line.
245   check_cache_or_override ("I1", I1c, DEFINED(clo_I1c));
246   check_cache_or_override ("D1", D1c, DEFINED(clo_D1c));
247   check_cache_or_override ("LL", LLc, DEFINED(clo_LLc));
248
249   // Then replace with any defined on the command line.  (Already checked in
250   // VG(parse_clo_cache_opt)().)
251   if (DEFINED(clo_I1c)) { *I1c = *clo_I1c; }
252   if (DEFINED(clo_D1c)) { *D1c = *clo_D1c; }
253   if (DEFINED(clo_LLc)) { *LLc = *clo_LLc; }
254
255   if (VG_(clo_verbosity) >= 2) {
256      VG_(umsg)("Cache configuration used:\n");
257      umsg_cache_img ("I1", I1c);
258      umsg_cache_img ("D1", D1c);
259      umsg_cache_img ("LL", LLc);
260   }
261#undef DEFINED
262}
263
264void VG_(print_cache_clo_opts)()
265{
266   VG_(printf)(
267"    --I1=<size>,<assoc>,<line_size>  set I1 cache manually\n"
268"    --D1=<size>,<assoc>,<line_size>  set D1 cache manually\n"
269"    --LL=<size>,<assoc>,<line_size>  set LL cache manually\n"
270               );
271}
272
273
274// Traverse the cache info and return a cache of the given kind and level.
275// Return NULL if no such cache exists.
276static const VexCache *
277locate_cache(const VexCacheInfo *ci, VexCacheKind kind, UInt level)
278{
279   const VexCache *c;
280
281   for (c = ci->caches; c != ci->caches + ci->num_caches; ++c) {
282      if (c->level == level && c->kind == kind) {
283         return c;
284      }
285   }
286   return NULL;  // not found
287}
288
289
290// Gives the auto-detected configuration of I1, D1 and LL caches.  They get
291// overridden by any cache configurations specified on the command line.
292static void
293configure_caches(cache_t *I1c, cache_t *D1c, cache_t *LLc,
294                 Bool all_caches_clo_defined)
295{
296   VexArchInfo vai;
297   const VexCacheInfo *ci;
298   const VexCache *i1, *d1, *ll;
299
300   VG_(machine_get_VexArchInfo)(NULL, &vai);
301   ci = &vai.hwcache_info;
302
303   // Extract what we need
304   i1 = locate_cache(ci, INSN_CACHE, 1);
305   d1 = locate_cache(ci, DATA_CACHE, 1);
306   ll = locate_cache(ci, UNIFIED_CACHE, ci->num_levels);
307
308   if (ci->num_caches > 0 && ll == NULL) {
309      VG_(dmsg)("warning: L2 cache not installed, ignore LL results.\n");
310   }
311
312   if (ll && ci->num_levels > 2) {
313      VG_(dmsg)("warning: L%u cache found, using its data for the "
314                "LL simulation.\n", ci->num_levels);
315   }
316
317   if (i1 && d1 && ll) {
318      if (i1->is_trace_cache) {
319         /* HACK ALERT: Instruction trace cache -- capacity is micro-ops based.
320          * conversion to byte size is a total guess;  treat the 12K and 16K
321          * cases the same since the cache byte size must be a power of two for
322          * everything to work!.  Also guessing 32 bytes for the line size...
323          */
324         UInt adjusted_size, guessed_line_size = 32;
325
326         if (i1->sizeB == 12 * 1024 || i1->sizeB == 16 * 1024) {
327            adjusted_size = 16 * 1024;
328         } else {
329            adjusted_size = 32 * 1024;
330         }
331         VG_(dmsg)("warning: Pentium 4 with %u KB micro-op instruction trace cache\n",
332                   i1->sizeB / 1024);
333         VG_(dmsg)("         Simulating a %d KB I-cache with %d B lines\n",
334                   adjusted_size / 1024, guessed_line_size);
335
336         *I1c = (cache_t) { adjusted_size, i1->assoc, guessed_line_size };
337      } else {
338         *I1c = (cache_t) { i1->sizeB, i1->assoc, i1->line_sizeB };
339      }
340      *D1c = (cache_t) { d1->sizeB, d1->assoc, d1->line_sizeB };
341      *LLc = (cache_t) { ll->sizeB, ll->assoc, ll->line_sizeB };
342
343      return;
344   }
345
346   // Cache information could not be queried; choose some default
347   // architecture specific default setting.
348
349#if defined(VGA_ppc32)
350
351   // Default cache configuration
352   *I1c = (cache_t) {  65536, 2, 64 };
353   *D1c = (cache_t) {  65536, 2, 64 };
354   *LLc = (cache_t) { 262144, 8, 64 };
355
356#elif defined(VGA_ppc64)
357
358   // Default cache configuration
359   *I1c = (cache_t) {  65536, 2, 64 };
360   *D1c = (cache_t) {  65536, 2, 64 };
361   *LLc = (cache_t) { 262144, 8, 64 };
362
363#elif defined(VGA_arm)
364
365   // Set caches to default (for Cortex-A8 ?)
366   *I1c = (cache_t) {  16384, 4, 64 };
367   *D1c = (cache_t) {  16384, 4, 64 };
368   *LLc = (cache_t) { 262144, 8, 64 };
369
370#elif defined(VGA_arm64)
371
372   // Copy the 32-bit ARM version until such time as we have
373   // some real hardware to run on
374   *I1c = (cache_t) {  16384, 4, 64 };
375   *D1c = (cache_t) {  16384, 4, 64 };
376   *LLc = (cache_t) { 262144, 8, 64 };
377
378#elif defined(VGA_s390x)
379   //
380   // Here is the cache data from older machine models:
381   //
382   //           I1            D1      I/D L2
383   // z900  256k/256/4    256k/256/4   16MB
384   // z800  256k/256/4    256k/256/4    8MB
385   // z990  256k/256/4    256k/256/4   32MB
386   // z890  256k/256/4    256k/256/4   32MB
387   // z9    256k/256/4    256k/256/4   40MB
388   //
389   // Sources:
390   // (1) IBM System z9 109 Technical Introduction
391   //     www.redbooks.ibm.com/redbooks/pdfs/sg246669.pdf
392   // (2) The microarchitecture of the IBM eServer z900 processor
393   //     IBM Journal of Research and Development
394   //     Volume 46, Number 4/5, pp 381-395, July/September 2002
395   // (3) The IBM eServer z990 microprocessor
396   //     IBM Journal of Research and Development
397   //     Volume 48, Number 3/4, pp 295-309, May/July 2004
398   // (4) Charles Webb, IBM
399   //
400   // L2 data is unfortunately incomplete. Otherwise, we could support
401   // machines without the ECAG insn by looking at VEX_S390X_MODEL(hwcaps).
402
403   // Default cache configuration is z10-EC  (Source: ECAG insn)
404   *I1c = (cache_t) {    65536,  4, 256 };
405   *D1c = (cache_t) {   131072,  8, 256 };
406   *LLc = (cache_t) { 50331648, 24, 256 };
407
408#elif defined(VGA_mips32)
409
410   // Set caches to default (for MIPS32-r2(mips 74kc))
411   *I1c = (cache_t) {  32768, 4, 32 };
412   *D1c = (cache_t) {  32768, 4, 32 };
413   *LLc = (cache_t) { 524288, 8, 32 };
414
415#elif defined(VGA_mips64)
416
417   // Set caches to default (for MIPS64 - 5kc)
418   *I1c = (cache_t) {  32768, 4, 32 };
419   *D1c = (cache_t) {  32768, 4, 32 };
420   *LLc = (cache_t) { 524288, 8, 32 };
421
422#elif defined(VGA_x86) || defined(VGA_amd64)
423
424   *I1c = (cache_t) {  65536, 2, 64 };
425   *D1c = (cache_t) {  65536, 2, 64 };
426   *LLc = (cache_t) { 262144, 8, 64 };
427
428#else
429
430#error "Unknown arch"
431
432#endif
433
434   if (!all_caches_clo_defined) {
435      const HChar warning[] =
436        "Warning: Cannot auto-detect cache config, using defaults.\n"
437        "         Run with -v to see.\n";
438      VG_(dmsg)("%s", warning);
439   }
440}
441
442/*--------------------------------------------------------------------*/
443/*--- end                                                          ---*/
444/*--------------------------------------------------------------------*/
445