1 /* Copyright (c) 2014. 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. */
7 #include "mc_private.h"
10 mc_mem_region_t mc_get_snapshot_region(void* addr, mc_snapshot_t snapshot)
12 for (size_t i = 0; i != NB_REGIONS; ++i) {
13 mc_mem_region_t region = snapshot->regions[i];
14 void* start = region->start_addr;
15 void* end = (char*) start + region->size;
17 if (addr >= start && addr < end) {
25 void* mc_translate_address_region(uintptr_t addr, mc_mem_region_t region)
27 xbt_assert(mc_region_contain(region, (void*) addr), "Trying to read out of the region boundary.");
34 else if (region->data) {
35 uintptr_t offset = addr - (uintptr_t) region->start_addr;
36 return (void *) ((uintptr_t) region->data + offset);
40 else if (region->page_numbers) {
41 size_t pageno = mc_page_number(region->start_addr, (void*) addr);
42 size_t snapshot_pageno = region->page_numbers[pageno];
43 const void* snapshot_page = mc_page_store_get_page(mc_model_checker->pages, snapshot_pageno);
44 return (char*) snapshot_page + mc_page_offset((void*) addr);
48 xbt_die("No data for this memory region");
52 void* mc_translate_address(uintptr_t addr, mc_snapshot_t snapshot)
55 // If not in a process state/clone:
57 return (uintptr_t *) addr;
60 mc_mem_region_t region = mc_get_snapshot_region((void*) addr, snapshot);
61 return mc_translate_address_region(addr, region);
64 /** @brief Read memory from a snapshot region broken across fragmented pages
66 * @param addr Process (non-snapshot) address of the data
67 * @param region Snapshot memory region where the data is located
68 * @param target Buffer to store the value
69 * @param size Size of the data to read in bytes
70 * @return Pointer where the data is located (target buffer of original location)
72 static void* mc_snapshot_read_fragmented(void* addr, mc_mem_region_t region, void* target, size_t size)
74 void* end = (char*) addr + size - 1;
75 size_t page_end = mc_page_number(NULL, end);
79 while (mc_page_number(NULL, addr) != page_end) {
80 void* snapshot_addr = mc_translate_address_region((uintptr_t) addr, region);
81 void* next_page = mc_page_from_number(NULL, mc_page_number(NULL, addr) + 1);
82 size_t readable = (char*) next_page - (char*) addr;
83 memcpy(dest, snapshot_addr, readable);
84 addr = (char*) addr + readable;
85 dest = (char*) dest + readable;
90 void* snapshot_addr = mc_translate_address_region((uintptr_t)addr, region);
91 memcpy(dest, snapshot_addr, size);
96 /** @brief Read memory from a snapshot region
98 * @param addr Process (non-snapshot) address of the data
99 * @param region Snapshot memory region where the data is located
100 * @param target Buffer to store the value
101 * @param size Size of the data to read in bytes
102 * @return Pointer where the data is located (target buffer of original location)
104 void* mc_snapshot_read_region(void* addr, mc_mem_region_t region, void* target, size_t size)
106 uintptr_t offset = (uintptr_t) addr - (uintptr_t) region->start_addr;
108 xbt_assert(addr >= region->start_addr && (char*) addr+size < (char*)region->start_addr+region->size,
109 "Trying to read out of the region boundary.");
111 // Linear memory region:
113 return (void*) ((uintptr_t) region->data + offset);
116 // Fragmented memory region:
117 else if (region->page_numbers) {
118 void* end = (char*) addr + size - 1;
119 if( mc_same_page(addr, end) ) {
120 // The memory is contained in a single page:
121 return mc_translate_address_region((uintptr_t) addr, region);
123 // The memory spans several pages:
124 return mc_snapshot_read_fragmented(addr, region, target, size);
129 xbt_die("No data available for this region");
133 /** @brief Read memory from a snapshot
135 * @param addr Process (non-snapshot) address of the data
136 * @param snapshot Snapshot (or NULL is no snapshot)
137 * @param target Buffer to store the value
138 * @param size Size of the data to read in bytes
139 * @return Pointer where the data is located (target buffer of original location)
141 void* mc_snapshot_read(void* addr, mc_snapshot_t snapshot, void* target, size_t size)
144 mc_mem_region_t region = mc_get_snapshot_region(addr, snapshot);
145 return mc_snapshot_read_region(addr, region, target, size);
151 /** Compare memory between snapshots (with known regions)
153 * @param addr1 Address in the first snapshot
154 * @param snapshot2 Region of the address in the first snapshot
155 * @param addr2 Address in the second snapshot
156 * @param snapshot2 Region of the address in the second snapshot
157 * @return same as memcmp
159 int mc_snapshot_region_memcp(
160 void* addr1, mc_mem_region_t region1,
161 void* addr2, mc_mem_region_t region2, size_t size)
163 // TODO, optimize this, avoid alloca
164 void* buffer1 = mc_snapshot_read_region(addr1, region1, alloca(size), size);
165 void* buffer2 = mc_snapshot_read_region(addr2, region2, alloca(size), size);
166 if (buffer1 == buffer2) {
169 return memcmp(buffer1, buffer2, size);
172 /** Compare memory between snapshots
174 * @param addr1 Address in the first snapshot
175 * @param snapshot1 First snapshot
176 * @param addr2 Address in the second snapshot
177 * @param snapshot2 Second snapshot
178 * @return same as memcmp
180 int mc_snapshot_memcp(
181 void* addr1, mc_snapshot_t snapshot1,
182 void* addr2, mc_snapshot_t snapshot2, size_t size)
184 // TODO, optimize this, avoid alloca
185 void* buffer1 = mc_snapshot_read(addr1, snapshot1, alloca(size), size);
186 void* buffer2 = mc_snapshot_read(addr2, snapshot2, alloca(size), size);
187 if (buffer1 == buffer2) {
190 return memcmp(buffer1, buffer2, size);