1 /* Copyright (c) 2014-2015. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
13 #include <sys/types.h>
17 #include <sys/mman.h> // PROT_*
23 #include <libunwind.h>
24 #include <libunwind-ptrace.h>
26 #include <xbt/mmalloc.h>
28 #include "mc_process.h"
29 #include "mc_object_info.h"
30 #include "mc_address_space.h"
32 #include "mc_snapshot.h"
33 #include "mc_ignore.h"
35 #include "mc_server.h"
39 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_process, mc,
40 "MC process information");
42 static void MC_process_init_memory_map_info(mc_process_t process);
43 static void MC_process_open_memory_file(mc_process_t process);
45 // ***** Destructor callbacks
47 // ***** mc_address_space methods for mc_process
49 static mc_process_t MC_process_get_process(mc_process_t p) {
53 static const s_mc_address_space_class_t mc_process_class = {
54 (mc_address_space_class_read_callback_t) &MC_process_read,
55 (mc_address_space_class_get_process_callback_t) MC_process_get_process
58 bool MC_is_process(mc_address_space_t p)
60 return p->address_space_class == &mc_process_class;
65 void MC_process_init(mc_process_t process, pid_t pid, int sockfd)
67 process->address_space.address_space_class = &mc_process_class;
68 process->process_flags = MC_PROCESS_NO_FLAG;
69 process->socket = sockfd;
72 process->process_flags |= MC_PROCESS_SELF_FLAG;
73 process->running = true;
75 process->memory_map = MC_get_memory_map(pid);
76 process->memory_file = -1;
77 process->cache_flags = MC_PROCESS_CACHE_FLAG_NONE;
79 process->heap_info = NULL;
80 MC_process_init_memory_map_info(process);
81 MC_process_open_memory_file(process);
83 // Read std_heap (is a struct mdesc*):
84 dw_variable_t std_heap_var = MC_process_find_variable_by_name(process,
85 "__mmalloc_default_mdp");
87 xbt_die("No heap information in the target process");
88 if(!std_heap_var->address)
89 xbt_die("No constant address for this variable");
90 MC_process_read(process, MC_ADDRESS_SPACE_READ_FLAGS_NONE,
91 &process->heap_address, std_heap_var->address, sizeof(struct mdesc*),
92 MC_PROCESS_INDEX_DISABLED);
94 process->smx_process_infos = MC_smx_process_info_list_new();
95 process->smx_old_process_infos = MC_smx_process_info_list_new();
97 process->checkpoint_ignore = MC_checkpoint_ignore_new();
99 process->unw_addr_space = unw_create_addr_space(&mc_unw_accessors , __BYTE_ORDER);
100 if (process->process_flags & MC_PROCESS_SELF_FLAG) {
101 process->unw_underlying_addr_space = unw_local_addr_space;
102 process->unw_underlying_context = NULL;
104 process->unw_underlying_addr_space = unw_create_addr_space(&mc_unw_vmread_accessors, __BYTE_ORDER);
105 process->unw_underlying_context = _UPT_create(pid);
109 void MC_process_clear(mc_process_t process)
111 process->address_space.address_space_class = NULL;
112 process->process_flags = MC_PROCESS_NO_FLAG;
115 MC_free_memory_map(process->memory_map);
116 process->memory_map = NULL;
118 process->maestro_stack_start = NULL;
119 process->maestro_stack_end = NULL;
121 xbt_dynar_free(&process->checkpoint_ignore);
123 xbt_dynar_free(&process->smx_process_infos);
124 xbt_dynar_free(&process->smx_old_process_infos);
127 for (i=0; i!=process->object_infos_size; ++i) {
128 MC_free_object_info(&process->object_infos[i]);
130 free(process->object_infos);
131 process->object_infos = NULL;
132 process->object_infos_size = 0;
133 if (process->memory_file >= 0) {
134 close(process->memory_file);
137 if (process->unw_underlying_addr_space != unw_local_addr_space) {
138 unw_destroy_addr_space(process->unw_underlying_addr_space);
139 _UPT_destroy(process->unw_underlying_context);
141 process->unw_underlying_context = NULL;
142 process->unw_underlying_addr_space = NULL;
144 unw_destroy_addr_space(process->unw_addr_space);
145 process->unw_addr_space = NULL;
147 process->cache_flags = MC_PROCESS_CACHE_FLAG_NONE;
150 process->heap = NULL;
152 free(process->heap_info);
153 process->heap_info = NULL;
156 void MC_process_refresh_heap(mc_process_t process)
158 xbt_assert(mc_mode == MC_MODE_SERVER);
159 xbt_assert(!MC_process_is_self(process));
160 // Read/dereference/refresh the std_heap pointer:
161 if (!process->heap) {
162 process->heap = (struct mdesc*) malloc(sizeof(struct mdesc));
164 MC_process_read(process, MC_ADDRESS_SPACE_READ_FLAGS_NONE,
165 process->heap, process->heap_address, sizeof(struct mdesc),
166 MC_PROCESS_INDEX_DISABLED
168 process->cache_flags |= MC_PROCESS_CACHE_FLAG_HEAP;
171 void MC_process_refresh_malloc_info(mc_process_t process)
173 xbt_assert(mc_mode == MC_MODE_SERVER);
174 xbt_assert(!MC_process_is_self(process));
175 if (!(process->cache_flags & MC_PROCESS_CACHE_FLAG_HEAP))
176 MC_process_refresh_heap(process);
177 // Refresh process->heapinfo:
178 size_t malloc_info_bytesize =
179 (process->heap->heaplimit + 1) * sizeof(malloc_info);
180 process->heap_info = (malloc_info*) realloc(process->heap_info, malloc_info_bytesize);
181 MC_process_read(process, MC_ADDRESS_SPACE_READ_FLAGS_NONE,
183 process->heap->heapinfo, malloc_info_bytesize,
184 MC_PROCESS_INDEX_DISABLED);
185 process->cache_flags |= MC_PROCESS_CACHE_FLAG_MALLOC_INFO;
188 #define SO_RE "\\.so[\\.0-9]*$"
189 #define VERSION_RE "-[\\.0-9]*$"
191 const char* FILTERED_LIBS[] = {
213 static bool MC_is_simgrid_lib(const char* libname)
215 return !strcmp(libname, "libsimgrid");
218 static bool MC_is_filtered_lib(const char* libname)
220 const size_t n = sizeof(FILTERED_LIBS) / sizeof(const char*);
223 if (strcmp(libname, FILTERED_LIBS[i])==0)
228 struct s_mc_memory_map_re {
233 static char* MC_get_lib_name(const char* pathname, struct s_mc_memory_map_re* res) {
234 const char* map_basename = basename((char*) pathname);
237 if(regexec(&res->so_re, map_basename, 1, &match, 0))
240 char* libname = strndup(map_basename, match.rm_so);
242 // Strip the version suffix:
243 if(libname && !regexec(&res->version_re, libname, 1, &match, 0)) {
244 char* temp = libname;
245 libname = strndup(temp, match.rm_so);
252 /** @brief Finds the range of the different memory segments and binary paths */
253 static void MC_process_init_memory_map_info(mc_process_t process)
255 XBT_DEBUG("Get debug information ...");
256 process->maestro_stack_start = NULL;
257 process->maestro_stack_end = NULL;
258 process->object_infos = NULL;
259 process->object_infos_size = 0;
260 process->binary_info = NULL;
261 process->libsimgrid_info = NULL;
263 struct s_mc_memory_map_re res;
265 if(regcomp(&res.so_re, SO_RE, 0) || regcomp(&res.version_re, VERSION_RE, 0))
266 xbt_die(".so regexp did not compile");
268 memory_map_t maps = process->memory_map;
270 const char* current_name = NULL;
272 for (ssize_t i=0; i < maps->mapsize; i++) {
273 map_region_t reg = &(maps->regions[i]);
274 const char* pathname = maps->regions[i].pathname;
277 if (maps->regions[i].pathname == NULL) {
282 // [stack], [vvar], [vsyscall], [vdso] ...
283 if (pathname[0] == '[') {
284 if ((reg->prot & PROT_WRITE) && !memcmp(pathname, "[stack]", 7)) {
285 process->maestro_stack_start = reg->start_addr;
286 process->maestro_stack_end = reg->end_addr;
292 if (current_name && strcmp(current_name, pathname)==0)
295 current_name = pathname;
296 if (!(reg->prot & PROT_READ) && (reg->prot & PROT_EXEC))
299 const bool is_executable = !i;
300 char* libname = NULL;
301 if (!is_executable) {
302 libname = MC_get_lib_name(pathname, &res);
305 if (MC_is_filtered_lib(libname)) {
311 mc_object_info_t info =
312 MC_find_object_info(process->memory_map, pathname, is_executable);
313 process->object_infos = (mc_object_info_t*) realloc(process->object_infos,
314 (process->object_infos_size+1) * sizeof(mc_object_info_t*));
315 process->object_infos[process->object_infos_size] = info;
316 process->object_infos_size++;
318 process->binary_info = info;
319 else if (libname && MC_is_simgrid_lib(libname))
320 process->libsimgrid_info = info;
325 regfree(&res.version_re);
327 // Resolve time (including accress differents objects):
328 for (size_t i=0; i!=process->object_infos_size; ++i)
329 MC_post_process_object_info(process, process->object_infos[i]);
331 xbt_assert(process->maestro_stack_start, "Did not find maestro_stack_start");
332 xbt_assert(process->maestro_stack_end, "Did not find maestro_stack_end");
334 XBT_DEBUG("Get debug information done !");
337 mc_object_info_t MC_process_find_object_info(mc_process_t process, const void *addr)
340 for (i = 0; i != process->object_infos_size; ++i) {
341 if (addr >= (void *) process->object_infos[i]->start
342 && addr <= (void *) process->object_infos[i]->end) {
343 return process->object_infos[i];
349 mc_object_info_t MC_process_find_object_info_exec(mc_process_t process, const void *addr)
352 for (i = 0; i != process->object_infos_size; ++i) {
353 if (addr >= (void *) process->object_infos[i]->start_exec
354 && addr <= (void *) process->object_infos[i]->end_exec) {
355 return process->object_infos[i];
361 mc_object_info_t MC_process_find_object_info_rw(mc_process_t process, const void *addr)
364 for (i = 0; i != process->object_infos_size; ++i) {
365 if (addr >= (void *) process->object_infos[i]->start_rw
366 && addr <= (void *) process->object_infos[i]->end_rw) {
367 return process->object_infos[i];
373 // Functions, variables…
375 dw_frame_t MC_process_find_function(mc_process_t process, const void *ip)
377 mc_object_info_t info = MC_process_find_object_info_exec(process, ip);
381 return MC_file_object_info_find_function(info, ip);
384 dw_variable_t MC_process_find_variable_by_name(mc_process_t process, const char* name)
386 const size_t n = process->object_infos_size;
389 // First lookup the variable in the executable shared object.
390 // A global variable used directly by the executable code from a library
391 // is reinstanciated in the executable memory .data/.bss.
392 // We need to look up the variable in the execvutable first.
393 if (process->binary_info) {
394 mc_object_info_t info = process->binary_info;
395 dw_variable_t var = MC_file_object_info_find_variable_by_name(info, name);
400 for (i=0; i!=n; ++i) {
401 mc_object_info_t info =process->object_infos[i];
402 dw_variable_t var = MC_file_object_info_find_variable_by_name(info, name);
410 void MC_process_read_variable(mc_process_t process, const char* name, void* target, size_t size)
412 dw_variable_t var = MC_process_find_variable_by_name(process, name);
414 xbt_die("No simple location for this variable");
415 if (!var->type->full_type)
416 xbt_die("Partial type for %s, cannot check size", name);
417 if ((size_t) var->type->full_type->byte_size != size)
418 xbt_die("Unexpected size for %s (expected %zi, was %zi)",
419 name, size, (size_t) var->type->full_type->byte_size);
420 MC_process_read(process, MC_ADDRESS_SPACE_READ_FLAGS_NONE, target, var->address, size,
421 MC_PROCESS_INDEX_ANY);
424 char* MC_process_read_string(mc_process_t process, void* address)
428 if (MC_process_is_self(process))
429 return strdup((char*) address);
432 char* res = (char*) malloc(len);
436 ssize_t c = pread(process->memory_file, res + off, len - off, (off_t) address + off);
441 xbt_die("Could not read from from remote process");
444 xbt_die("Could not read string from remote process");
446 void* p = memchr(res + off, '\0', c);
453 res = (char*) realloc(res, len);
458 // ***** Memory access
460 int MC_process_vm_open(pid_t pid, int flags)
462 const size_t buffer_size = 30;
463 char buffer[buffer_size];
464 int res = snprintf(buffer, buffer_size, "/proc/%lli/mem", (long long) pid);
465 if (res < 0 || (size_t) res >= buffer_size) {
466 errno = ENAMETOOLONG;
469 return open(buffer, flags);
472 static void MC_process_open_memory_file(mc_process_t process)
474 if (MC_process_is_self(process) || process->memory_file >= 0)
477 int fd = MC_process_vm_open(process->pid, O_RDWR);
479 xbt_die("Could not open file for process virtual address space");
480 process->memory_file = fd;
483 static ssize_t pread_whole(int fd, void *buf, size_t count, off_t offset)
485 char* buffer = (char*) buf;
486 ssize_t real_count = count;
488 ssize_t res = pread(fd, buffer, count, offset);
495 } else if (errno != EINTR) {
502 static ssize_t pwrite_whole(int fd, const void *buf, size_t count, off_t offset)
504 const char* buffer = (const char*) buf;
505 ssize_t real_count = count;
507 ssize_t res = pwrite(fd, buffer, count, offset);
514 } else if (errno != EINTR) {
521 const void* MC_process_read(mc_process_t process, adress_space_read_flags_t flags,
522 void* local, const void* remote, size_t len,
525 if (process_index != MC_PROCESS_INDEX_DISABLED) {
526 mc_object_info_t info = MC_process_find_object_info_rw(process, remote);
527 // Segment overlap is not handled.
528 if (MC_object_info_is_privatized(info)) {
529 if (process_index < 0)
530 xbt_die("Missing process index");
531 // Address translation in the privaization segment:
532 size_t offset = (const char*) remote - info->start_rw;
533 remote = (const char*) remote - offset;
537 if (MC_process_is_self(process)) {
538 if (flags & MC_ADDRESS_SPACE_READ_FLAGS_LAZY)
541 memcpy(local, remote, len);
545 if (pread_whole(process->memory_file, local, len, (off_t) remote) < 0)
546 xbt_die("Read from process %lli failed", (long long) process->pid);
551 const void* MC_process_read_simple(mc_process_t process,
552 void* local, const void* remote, size_t len)
554 adress_space_read_flags_t flags = MC_ADDRESS_SPACE_READ_FLAGS_NONE;
555 int index = MC_PROCESS_INDEX_ANY;
556 MC_process_read(process, flags, local, remote, len, index);
560 const void* MC_process_read_dynar_element(mc_process_t process,
561 void* local, const void* remote_dynar, size_t i, size_t len)
564 MC_process_read_simple(process, &d, remote_dynar, sizeof(d));
566 xbt_die("Out of bound index %zi/%lu", i, d.used);
567 if (len != d.elmsize)
568 xbt_die("Bad size in MC_process_read_dynar_element");
569 MC_process_read_simple(process, local, xbt_dynar_get_ptr(&d, i), len);
573 void MC_process_write(mc_process_t process, const void* local, void* remote, size_t len)
575 if (MC_process_is_self(process)) {
576 memcpy(remote, local, len);
578 if (pwrite_whole(process->memory_file, local, len, (off_t) remote) < 0)
579 xbt_die("Write to process %lli failed", (long long) process->pid);
583 unsigned long MC_process_read_dynar_length(mc_process_t process, const void* remote_dynar)
588 MC_process_read_simple(process, &res,
589 &((xbt_dynar_t)remote_dynar)->used, sizeof(res));
593 static pthread_once_t zero_buffer_flag = PTHREAD_ONCE_INIT;
594 static const void* zero_buffer;
595 static const size_t zero_buffer_size = 10 * 4096;
597 static void MC_zero_buffer_init(void)
599 int fd = open("/dev/zero", O_RDONLY);
601 xbt_die("Could not open /dev/zero");
602 zero_buffer = mmap(NULL, zero_buffer_size, PROT_READ, MAP_SHARED, fd, 0);
603 if (zero_buffer == MAP_FAILED)
604 xbt_die("Could not map the zero buffer");
608 void MC_process_clear_memory(mc_process_t process, void* remote, size_t len)
610 if (MC_process_is_self(process)) {
611 memset(remote, 0, len);
613 pthread_once(&zero_buffer_flag, MC_zero_buffer_init);
615 size_t s = len > zero_buffer_size ? zero_buffer_size : len;
616 MC_process_write(process, zero_buffer, remote, s);
617 remote = (char*) remote + s;