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[mc] Read smpi_privatisation_regions from MCed in MC_region_new_privatized()
[simgrid.git] / src / mc / mc_process.c
1 #include <assert.h>
2 #include <stddef.h>
3 #include <stdbool.h>
4 #include <stdint.h>
5 #include <errno.h>
6
7 #include <sys/types.h>
8 #include <fcntl.h>
9 #include <unistd.h>
10 #include <regex.h>
11 #include <sys/mman.h> // PROT_*
12
13 #include <pthread.h>
14
15 #include <libgen.h>
16
17 #include <libunwind.h>
18 #include <libunwind-ptrace.h>
19
20 #include <xbt/mmalloc.h>
21
22 #include "mc_process.h"
23 #include "mc_object_info.h"
24 #include "mc_address_space.h"
25 #include "mc_unw.h"
26 #include "mc_snapshot.h"
27 #include "mc_ignore.h"
28 #include "mc_smx.h"
29
30 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc,
31                                 "MC process information");
32
33 static void MC_process_init_memory_map_info(mc_process_t process);
34 static void MC_process_open_memory_file(mc_process_t process);
35
36 // ***** Destructor callbacks
37
38 // ***** mc_address_space methods for mc_process
39
40 static mc_process_t MC_process_get_process(mc_process_t p) {
41   return p;
42 }
43
44 static const s_mc_address_space_class_t mc_process_class = {
45   .read = (void*) &MC_process_read,
46   .get_process = (void*) MC_process_get_process
47 };
48
49 bool MC_is_process(mc_address_space_t p)
50 {
51   return p->address_space_class == &mc_process_class;
52 }
53
54 // ***** mc_process
55
56 void MC_process_init(mc_process_t process, pid_t pid, int sockfd)
57 {
58   process->address_space.address_space_class = &mc_process_class;
59   process->process_flags = MC_PROCESS_NO_FLAG;
60   process->socket = sockfd;
61   process->pid = pid;
62   if (pid==getpid())
63     process->process_flags |= MC_PROCESS_SELF_FLAG;
64   process->running = true;
65   process->status = 0;
66   process->memory_map = MC_get_memory_map(pid);
67   process->memory_file = -1;
68   process->cache_flags = 0;
69   process->heap = NULL;
70   process->heap_info = NULL;
71   MC_process_init_memory_map_info(process);
72   MC_process_open_memory_file(process);
73
74   // Read std_heap (is a struct mdesc*):
75   dw_variable_t std_heap_var = MC_process_find_variable_by_name(process, "std_heap");
76   if (!std_heap_var)
77     xbt_die("No heap information in the target process");
78   if(!std_heap_var->address)
79     xbt_die("No constant address for this variable");
80   MC_process_read(process, MC_ADDRESS_SPACE_READ_FLAGS_NONE,
81     &process->heap_address, std_heap_var->address, sizeof(struct mdesc*),
82     MC_PROCESS_INDEX_DISABLED);
83
84   process->smx_process_infos = MC_smx_process_info_list_new();
85   process->smx_old_process_infos = MC_smx_process_info_list_new();
86
87   process->checkpoint_ignore = MC_checkpoint_ignore_new();
88
89   process->unw_addr_space = unw_create_addr_space(&mc_unw_accessors  , __BYTE_ORDER);
90   if (process->process_flags & MC_PROCESS_SELF_FLAG) {
91     process->unw_underlying_addr_space = unw_local_addr_space;
92     process->unw_underlying_context = NULL;
93   } else {
94     process->unw_underlying_addr_space = unw_create_addr_space(&mc_unw_vmread_accessors, __BYTE_ORDER);
95     process->unw_underlying_context = _UPT_create(pid);
96   }
97 }
98
99 void MC_process_clear(mc_process_t process)
100 {
101   process->address_space.address_space_class = NULL;
102   process->process_flags = MC_PROCESS_NO_FLAG;
103   process->pid = 0;
104
105   MC_free_memory_map(process->memory_map);
106   process->memory_map = NULL;
107
108   process->maestro_stack_start = NULL;
109   process->maestro_stack_end = NULL;
110
111   xbt_dynar_free(&process->checkpoint_ignore);
112
113   xbt_dynar_free(&process->smx_process_infos);
114   xbt_dynar_free(&process->smx_old_process_infos);
115
116   size_t i;
117   for (i=0; i!=process->object_infos_size; ++i) {
118     MC_free_object_info(&process->object_infos[i]);
119   }
120   free(process->object_infos);
121   process->object_infos = NULL;
122   process->object_infos_size = 0;
123   if (process->memory_file >= 0) {
124     close(process->memory_file);
125   }
126
127   if (process->unw_underlying_addr_space != unw_local_addr_space) {
128     unw_destroy_addr_space(process->unw_underlying_addr_space);
129     _UPT_destroy(process->unw_underlying_context);
130   }
131   process->unw_underlying_context = NULL;
132   process->unw_underlying_addr_space = NULL;
133
134   unw_destroy_addr_space(process->unw_addr_space);
135   process->unw_addr_space = NULL;
136
137   process->cache_flags = 0;
138
139   free(process->heap);
140   process->heap = NULL;
141
142   free(process->heap_info);
143   process->heap_info = NULL;
144 }
145
146 void MC_process_refresh_heap(mc_process_t process)
147 {
148   assert(!MC_process_is_self(process));
149   // Read/dereference/refresh the std_heap pointer:
150   if (!process->heap) {
151     xbt_mheap_t oldheap  = mmalloc_set_current_heap(mc_heap);
152     process->heap = malloc(sizeof(struct mdesc));
153     mmalloc_set_current_heap(oldheap);
154   }
155   MC_process_read(process, MC_ADDRESS_SPACE_READ_FLAGS_NONE,
156     process->heap, process->heap_address, sizeof(struct mdesc),
157     MC_PROCESS_INDEX_DISABLED
158     );
159 }
160
161 void MC_process_refresh_malloc_info(mc_process_t process)
162 {
163   assert(!MC_process_is_self(process));
164   if (!process->cache_flags & MC_PROCESS_CACHE_FLAG_HEAP)
165     MC_process_refresh_heap(process);
166   // Refresh process->heapinfo:
167   size_t malloc_info_bytesize = process->heap->heaplimit * sizeof(malloc_info);
168
169   xbt_mheap_t heap  = mmalloc_set_current_heap(mc_heap);
170   process->heap_info = (malloc_info*) realloc(process->heap_info,
171     malloc_info_bytesize);
172   mmalloc_set_current_heap(heap);
173
174   MC_process_read(process, MC_ADDRESS_SPACE_READ_FLAGS_NONE,
175     process->heap_info,
176     process->heap->heapinfo, malloc_info_bytesize,
177     MC_PROCESS_INDEX_DISABLED);
178 }
179
180 #define SO_RE "\\.so[\\.0-9]*$"
181 #define VERSION_RE "-[\\.0-9]*$"
182
183 const char* FILTERED_LIBS[] = {
184   "libstdc++",
185   "libc++",
186   "libm",
187   "libgcc_s",
188   "libpthread",
189   "libunwind",
190   "libunwind-x86_64",
191   "libunwind-x86",
192   "libunwind-ptrace",
193   "libdw",
194   "libdl",
195   "librt",
196   "liblzma",
197   "libelf",
198   "libbz2",
199   "libz",
200   "libelf",
201   "libc",
202   "ld"
203 };
204
205 static bool MC_is_simgrid_lib(const char* libname)
206 {
207   return !strcmp(libname, "libsimgrid");
208 }
209
210 static bool MC_is_filtered_lib(const char* libname)
211 {
212   const size_t n = sizeof(FILTERED_LIBS) / sizeof(const char*);
213   size_t i;
214   for (i=0; i!=n; ++i)
215     if (strcmp(libname, FILTERED_LIBS[i])==0)
216       return true;
217   return false;
218 }
219
220 struct s_mc_memory_map_re {
221   regex_t so_re;
222   regex_t version_re;
223 };
224
225 static char* MC_get_lib_name(const char* pathname, struct s_mc_memory_map_re* res) {
226   const char* map_basename = basename((char*) pathname);
227
228   regmatch_t match;
229   if(regexec(&res->so_re, map_basename, 1, &match, 0))
230     return NULL;
231
232   char* libname = strndup(map_basename, match.rm_so);
233
234   // Strip the version suffix:
235   if(libname && !regexec(&res->version_re, libname, 1, &match, 0)) {
236     char* temp = libname;
237     libname = strndup(temp, match.rm_so);
238     free(temp);
239   }
240
241   return libname;
242 }
243
244 /** @brief Finds the range of the different memory segments and binary paths */
245 static void MC_process_init_memory_map_info(mc_process_t process)
246 {
247   XBT_DEBUG("Get debug information ...");
248   process->maestro_stack_start = NULL;
249   process->maestro_stack_end = NULL;
250   process->object_infos = NULL;
251   process->object_infos_size = 0;
252   process->binary_info = NULL;
253   process->libsimgrid_info = NULL;
254
255   struct s_mc_memory_map_re res;
256
257   if(regcomp(&res.so_re, SO_RE, 0) || regcomp(&res.version_re, VERSION_RE, 0))
258     xbt_die(".so regexp did not compile");
259
260   memory_map_t maps = process->memory_map;
261
262   const char* current_name = NULL;
263
264   size_t i = 0;
265   for (i=0; i < maps->mapsize; i++) {
266     map_region_t reg = &(maps->regions[i]);
267     const char* pathname = maps->regions[i].pathname;
268
269     // Nothing to do
270     if (maps->regions[i].pathname == NULL) {
271       current_name = NULL;
272       continue;
273     }
274
275     // [stack], [vvar], [vsyscall], [vdso] ...
276     if (pathname[0] == '[') {
277       if ((reg->prot & PROT_WRITE) && !memcmp(pathname, "[stack]", 7)) {
278         process->maestro_stack_start = reg->start_addr;
279         process->maestro_stack_end = reg->end_addr;
280       }
281       current_name = NULL;
282       continue;
283     }
284
285     if (current_name && strcmp(current_name, pathname)==0)
286       continue;
287
288     current_name = pathname;
289     if (!(reg->prot & PROT_READ) && (reg->prot & PROT_EXEC))
290       continue;
291
292     const bool is_executable = !i;
293     char* libname = NULL;
294     if (!is_executable) {
295       libname = MC_get_lib_name(pathname, &res);
296       if(!libname)
297         continue;
298       if (MC_is_filtered_lib(libname)) {
299         free(libname);
300         continue;
301       }
302     }
303
304     mc_object_info_t info =
305       MC_find_object_info(process->memory_map, pathname, is_executable);
306     process->object_infos = (mc_object_info_t*) realloc(process->object_infos,
307       (process->object_infos_size+1) * sizeof(mc_object_info_t*));
308     process->object_infos[process->object_infos_size] = info;
309     process->object_infos_size++;
310     if (is_executable)
311       process->binary_info = info;
312     else if (libname && MC_is_simgrid_lib(libname))
313       process->libsimgrid_info = info;
314     free(libname);
315   }
316
317   regfree(&res.so_re);
318   regfree(&res.version_re);
319
320   // Resolve time (including accress differents objects):
321   for (i=0; i!=process->object_infos_size; ++i)
322     MC_post_process_object_info(process, process->object_infos[i]);
323
324   xbt_assert(process->maestro_stack_start, "Did not find maestro_stack_start");
325   xbt_assert(process->maestro_stack_end, "Did not find maestro_stack_end");
326
327   XBT_DEBUG("Get debug information done !");
328 }
329
330 mc_object_info_t MC_process_find_object_info(mc_process_t process, const void *addr)
331 {
332   size_t i;
333   for (i = 0; i != process->object_infos_size; ++i) {
334     if (addr >= (void *) process->object_infos[i]->start
335         && addr <= (void *) process->object_infos[i]->end) {
336       return process->object_infos[i];
337     }
338   }
339   return NULL;
340 }
341
342 mc_object_info_t MC_process_find_object_info_exec(mc_process_t process, const void *addr)
343 {
344   size_t i;
345   for (i = 0; i != process->object_infos_size; ++i) {
346     if (addr >= (void *) process->object_infos[i]->start_exec
347         && addr <= (void *) process->object_infos[i]->end_exec) {
348       return process->object_infos[i];
349     }
350   }
351   return NULL;
352 }
353
354 mc_object_info_t MC_process_find_object_info_rw(mc_process_t process, const void *addr)
355 {
356   size_t i;
357   for (i = 0; i != process->object_infos_size; ++i) {
358     if (addr >= (void *) process->object_infos[i]->start_rw
359         && addr <= (void *) process->object_infos[i]->end_rw) {
360       return process->object_infos[i];
361     }
362   }
363   return NULL;
364 }
365
366 // Functions, variables…
367
368 dw_frame_t MC_process_find_function(mc_process_t process, const void *ip)
369 {
370   mc_object_info_t info = MC_process_find_object_info_exec(process, ip);
371   if (info == NULL)
372     return NULL;
373   else
374     return MC_file_object_info_find_function(info, ip);
375 }
376
377 dw_variable_t MC_process_find_variable_by_name(mc_process_t process, const char* name)
378 {
379   const size_t n = process->object_infos_size;
380   size_t i;
381
382   // First lookup the variable in the executable shared object.
383   // A global variable used directly by the executable code from a library
384   // is reinstanciated in the executable memory .data/.bss.
385   // We need to look up the variable in the execvutable first.
386   if (process->binary_info) {
387     mc_object_info_t info = process->binary_info;
388     dw_variable_t var = MC_file_object_info_find_variable_by_name(info, name);
389     if (var)
390       return var;
391   }
392
393   for (i=0; i!=n; ++i) {
394     mc_object_info_t info =process->object_infos[i];
395     dw_variable_t var = MC_file_object_info_find_variable_by_name(info, name);
396     if (var)
397       return var;
398   }
399
400   return NULL;
401 }
402
403 void MC_process_read_variable(mc_process_t process, const char* name, void* target, size_t size)
404 {
405   dw_variable_t var = MC_process_find_variable_by_name(process, name);
406   if (!var->address)
407     xbt_die("No simple location for this variable");
408   MC_process_read(process, MC_PROCESS_NO_FLAG, target, var->address, size,
409     MC_PROCESS_INDEX_ANY);
410 }
411
412 // ***** Memory access
413
414 int MC_process_vm_open(pid_t pid, int flags)
415 {
416   const size_t buffer_size = 30;
417   char buffer[buffer_size];
418   int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long) pid);
419   if (res < 0 || res >= buffer_size) {
420     errno = ENAMETOOLONG;
421     return -1;
422   }
423   return open(buffer, flags);
424 }
425
426 static void MC_process_open_memory_file(mc_process_t process)
427 {
428   if (MC_process_is_self(process) || process->memory_file >= 0)
429     return;
430
431   int fd = MC_process_vm_open(process->pid, O_RDWR);
432   if (fd<0)
433     xbt_die("Could not open file for process virtual address space");
434   process->memory_file = fd;
435 }
436
437 static ssize_t pread_whole(int fd, void *buf, size_t count, off_t offset)
438 {
439   char* buffer = (char*) buf;
440   ssize_t real_count = count;
441   while (count) {
442     ssize_t res = pread(fd, buffer, count, offset);
443     if (res > 0) {
444       count  -= res;
445       buffer += res;
446       offset += res;
447     } else if (res==0) {
448       return -1;
449     } else if (errno != EINTR) {
450       return -1;
451     }
452   }
453   return real_count;
454 }
455
456 static ssize_t pwrite_whole(int fd, const void *buf, size_t count, off_t offset)
457 {
458   const char* buffer = (const char*) buf;
459   ssize_t real_count = count;
460   while (count) {
461     ssize_t res = pwrite(fd, buffer, count, offset);
462     if (res > 0) {
463       count  -= res;
464       buffer += res;
465       offset += res;
466     } else if (res==0) {
467       return -1;
468     } else if (errno != EINTR) {
469       return -1;
470     }
471   }
472   return real_count;
473 }
474
475 const void* MC_process_read(mc_process_t process, e_adress_space_read_flags_t flags,
476   void* local, const void* remote, size_t len,
477   int process_index)
478 {
479   if (process_index != MC_PROCESS_INDEX_DISABLED) {
480     mc_object_info_t info = MC_process_find_object_info_rw(process, remote);
481     // Segment overlap is not handled.
482     if (MC_object_info_is_privatized(info)) {
483       if (process_index < 0)
484         xbt_die("Missing process index");
485       // Address translation in the privaization segment:
486       size_t offset = (const char*) remote - info->start_rw;
487       remote = (const char*) remote - offset;
488     }
489   }
490
491   if (MC_process_is_self(process)) {
492     if (flags & MC_ADDRESS_SPACE_READ_FLAGS_LAZY)
493       return remote;
494     else {
495       memcpy(local, remote, len);
496       return local;
497     }
498   } else {
499     if (pread_whole(process->memory_file, local, len, (off_t) remote) < 0)
500       xbt_die("Read from process %lli failed", (long long) process->pid);
501     return local;
502   }
503 }
504
505 const void* MC_process_read_simple(mc_process_t process,
506   void* local, const void* remote, size_t len)
507 {
508   e_adress_space_read_flags_t flags = MC_PROCESS_NO_FLAG;
509   int index = MC_PROCESS_INDEX_ANY;
510    MC_process_read(process, flags, local, remote, len, index);
511    return local;
512 }
513
514 const void* MC_process_read_dynar_element(mc_process_t process,
515   void* local, const void* remote_dynar, size_t i)
516 {
517   s_xbt_dynar_t d;
518   MC_process_read_simple(process, &d, remote_dynar, sizeof(d));
519   MC_process_read_simple(process, local, xbt_dynar_get_ptr(&d, i), i);
520   return local;
521 }
522
523 void MC_process_write(mc_process_t process, const void* local, void* remote, size_t len)
524 {
525   if (MC_process_is_self(process)) {
526     memcpy(remote, local, len);
527   } else {
528     if (pwrite_whole(process->memory_file, local, len, (off_t) remote) < 0)
529       xbt_die("Write to process %lli failed", (long long) process->pid);
530   }
531 }
532
533 unsigned long MC_process_read_dynar_length(mc_process_t process, const void* remote_dynar)
534 {
535   if (!remote_dynar)
536     return 0;
537   unsigned long res;
538   MC_process_read_simple(process, &res,
539     &((xbt_dynar_t)remote_dynar)->used, sizeof(res));
540   return res;
541 }
542
543 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
544 static const void* zero_buffer;
545 static const int zero_buffer_size = 10 * 4096;
546
547 static void MC_zero_buffer_init(void)
548 {
549   int fd = open("/dev/zero", O_RDONLY);
550   if (fd<0)
551     xbt_die("Could not open /dev/zero");
552   zero_buffer = mmap(NULL, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
553   if (zero_buffer == MAP_FAILED)
554     xbt_die("Could not map the zero buffer");
555   close(fd);
556 }
557
558 void MC_process_clear_memory(mc_process_t process, void* remote, size_t len)
559 {
560   if (MC_process_is_self(process)) {
561     memset(remote, 0, len);
562   } else {
563     pthread_once(&zero_buffer_flag, MC_zero_buffer_init);
564     while (len) {
565       size_t s = len > zero_buffer_size ? zero_buffer_size : len;
566       MC_process_write(process, zero_buffer, remote, s);
567       remote = (char*) remote + s;
568       len -= s;
569     }
570   }
571 }
572
573 void MC_simcall_handle(smx_simcall_t req, int value)
574 {
575   if (MC_process_is_self(&mc_model_checker->process)) {
576     SIMIX_simcall_handle(req, value);
577     return;
578   }
579
580   MC_process_smx_refresh(&mc_model_checker->process);
581
582   unsigned i;
583   mc_smx_process_info_t pi = NULL;
584
585   xbt_dynar_foreach_ptr(mc_model_checker->process.smx_process_infos, i, pi) {
586     smx_process_t p = (smx_process_t) pi->address;
587     if (req == &pi->copy.simcall) {
588       smx_simcall_t real_req = &p->simcall;
589       // TODO, use a remote call
590       SIMIX_simcall_handle(real_req, value);
591       return;
592     }
593   }
594
595   // Check (remove afterwards):
596   xbt_dynar_foreach_ptr(mc_model_checker->process.smx_process_infos, i, pi) {
597     smx_process_t p = (smx_process_t) pi->address;
598     if (req == &p->simcall)
599       xbt_die("The real simcall was passed. We expected the local copy.");
600   }
601
602   xbt_die("Could not find the request");
603 }