/** Compare memory between snapshots (with known regions)
*
* @param addr1 Address in the first snapshot
* @param snapshot2 Region of the address in the first snapshot
* @param addr2 Address in the second snapshot
* @param snapshot2 Region of the address in the second snapshot
* @return same as memcmp
* */
int MC_snapshot_region_memcmp(
const void* addr1, mc_mem_region_t region1,
const void* addr2, mc_mem_region_t region2,
size_t size)
{
// Using alloca() for large allocations may trigger stack overflow:
// use malloc if the buffer is too big.
bool stack_alloc = size < 64;
const bool region1_need_buffer = region1==NULL || region1->storage_type()==simgrid::mc::StorageType::Flat;
const bool region2_need_buffer = region2==NULL || region2->storage_type()==simgrid::mc::StorageType::Flat;
void* buffer1a = region1_need_buffer ? NULL : stack_alloc ? alloca(size) : malloc(size);
void* buffer2a = region2_need_buffer ? NULL : stack_alloc ? alloca(size) : malloc(size);
const void* buffer1 = MC_region_read(region1, buffer1a, addr1, size);
const void* buffer2 = MC_region_read(region2, buffer2a, addr2, size);
int res;
if (buffer1 == buffer2) {
res = 0;
} else {
res = memcmp(buffer1, buffer2, size);
}
if (!stack_alloc) {
free(buffer1a);
free(buffer2a);
}
return res;
}
/** Compare memory between snapshots (with known regions)
*
* @param addr1 Address in the first snapshot
* @param region1 Region of the address in the first snapshot
* @param addr2 Address in the second snapshot
* @param region2 Region of the address in the second snapshot
* @return same semantic as memcmp
*/
int MC_snapshot_region_memcmp(const void* addr1, mc_mem_region_t region1, const void* addr2, mc_mem_region_t region2,
size_t size)
{
// Using alloca() for large allocations may trigger stack overflow:
// use malloc if the buffer is too big.
bool stack_alloc = size < 64;
void* buffer1a = nullptr;
void* buffer2a = nullptr;
if (region1 != nullptr && region1->storage_type() != simgrid::mc::StorageType::Flat)
buffer1a = stack_alloc ? alloca(size) : ::operator new(size);
if (region2 != nullptr && region2->storage_type() != simgrid::mc::StorageType::Flat)
buffer2a = stack_alloc ? alloca(size) : ::operator new(size);
const void* buffer1 = MC_region_read(region1, buffer1a, addr1, size);
const void* buffer2 = MC_region_read(region2, buffer2a, addr2, size);
int res;
if (buffer1 == buffer2)
res = 0;
else
res = memcmp(buffer1, buffer2, size);
if (not stack_alloc) {
::operator delete(buffer1a);
::operator delete(buffer2a);
}
return res;
}
const void* Snapshot::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
ReadOptions options) const
{
mc_mem_region_t region = mc_get_snapshot_region((void*)address.address(), this, process_index);
if (region) {
const void* res = MC_region_read(region, buffer, (void*)address.address(), size);
if (buffer == res || options & ReadOptions::lazy())
return res;
else {
memcpy(buffer, res, size);
return buffer;
}
} else
return this->process()->read_bytes(buffer, size, address, process_index, options);
}
const void* Snapshot::read_bytes(void* buffer, std::size_t size,
remote_ptr<void> address, int process_index,
AddressSpace::ReadMode mode) const
{
mc_mem_region_t region = mc_get_snapshot_region((void*)address.address(), this, process_index);
if (region) {
const void* res = MC_region_read(region, buffer, (void*)address.address(), size);
if (buffer == res || mode == AddressSpace::Lazy)
return res;
else {
memcpy(buffer, res, size);
return buffer;
}
}
else
return this->process()->read_bytes(
buffer, size, address, process_index, mode);
}
static void test_snapshot(bool sparse_checkpoint) {
xbt_test_add("Initialisation");
_sg_mc_sparse_checkpoint = sparse_checkpoint;
xbt_assert(xbt_pagesize == getpagesize());
xbt_assert(1 << xbt_pagebits == xbt_pagesize);
mc_model_checker = new ::simgrid::mc::ModelChecker(getpid(), -1);
for(int n=1; n!=256; ++n) {
// Store region page(s):
size_t byte_size = n * xbt_pagesize;
void* source = mmap(NULL, byte_size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
xbt_assert(source!=MAP_FAILED, "Could not allocate source memory");
// Init memory and take snapshots:
init_memory(source, byte_size);
simgrid::mc::RegionSnapshot region0 = simgrid::mc::sparse_region(
simgrid::mc::RegionType::Unknown, source, source, byte_size, nullptr);
for(int i=0; i<n; i+=2) {
init_memory((char*) source + i*xbt_pagesize, xbt_pagesize);
}
simgrid::mc::RegionSnapshot region = simgrid::mc::sparse_region(
simgrid::mc::RegionType::Unknown, source, source, byte_size, nullptr);
void* destination = mmap(NULL, byte_size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
xbt_assert(source!=MAP_FAILED, "Could not allocate destination memory");
xbt_test_add("Reading whole region data for %i page(s)", n);
const void* read = MC_region_read(®ion, destination, source, byte_size);
xbt_test_assert(!memcmp(source, read, byte_size), "Mismatch in MC_region_read()");
xbt_test_add("Reading parts of region data for %i page(s)", n);
for(int j=0; j!=100; ++j) {
size_t offset = rand() % byte_size;
size_t size = rand() % (byte_size - offset);
const void* read = MC_region_read(®ion, destination, (const char*) source+offset, size);
xbt_test_assert(!memcmp((char*) source+offset, read, size),
"Mismatch in MC_region_read()");
}
xbt_test_add("Compare whole region data for %i page(s)", n);
xbt_test_assert(MC_snapshot_region_memcmp(source, ®ion0, source, ®ion, byte_size),
"Unexpected match in MC_snapshot_region_memcmp() with previous snapshot");
xbt_test_add("Compare parts of region data for %i page(s) with itself", n);
for(int j=0; j!=100; ++j) {
size_t offset = rand() % byte_size;
size_t size = rand() % (byte_size - offset);
xbt_test_assert(!MC_snapshot_region_memcmp((char*) source+offset, ®ion, (char*) source+offset, ®ion, size),
"Mismatch in MC_snapshot_region_memcmp()");
}
if (n==1) {
xbt_test_add("Read pointer for %i page(s)", n);
memcpy(source, &mc_model_checker, sizeof(void*));
simgrid::mc::RegionSnapshot region2 = simgrid::mc::sparse_region(
simgrid::mc::RegionType::Unknown, source, source, byte_size, nullptr);
xbt_test_assert(MC_region_read_pointer(®ion2, source) == mc_model_checker,
"Mismtach in MC_region_read_pointer()");
}
munmap(destination, byte_size);
munmap(source, byte_size);
}
delete mc_model_checker;
mc_model_checker = NULL;
}
