/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
-#include <cstddef>
+#include <cstddef> /* std::size_t */
-#include <memory>
-#include <utility>
-
-#include "xbt/asserts.h"
-#include "xbt/sysdep.h"
-
-#include "src/internal_config.h"
-#include "src/smpi/include/private.hpp"
-
-#include "src/mc/mc_mmu.hpp"
-#include "src/mc/mc_private.hpp"
+#include "src/mc/mc_config.hpp"
+#include "src/mc/mc_hash.hpp"
#include "src/mc/mc_smx.hpp"
-#include "src/mc/sosp/PageStore.hpp"
#include "src/mc/sosp/mc_snapshot.hpp"
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_snapshot, mc, "Taking and restoring snapshots");
/** @brief Read memory from a snapshot region broken across fragmented pages
*
// Read each page:
while (simgrid::mc::mmu::split((std::uintptr_t)addr).first != page_end) {
- void* snapshot_addr = mc_translate_address_region_chunked((uintptr_t)addr, region);
+ void* snapshot_addr = mc_translate_address_region((uintptr_t)addr, region);
void* next_page = (void*)simgrid::mc::mmu::join(simgrid::mc::mmu::split((std::uintptr_t)addr).first + 1, 0);
size_t readable = (char*)next_page - (char*)addr;
memcpy(dest, snapshot_addr, readable);
}
// Read the end:
- void* snapshot_addr = mc_translate_address_region_chunked((uintptr_t)addr, region);
+ void* snapshot_addr = mc_translate_address_region((uintptr_t)addr, region);
memcpy(dest, snapshot_addr, size);
return target;
// 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);
+ void* buffer1a = stack_alloc ? alloca(size) : ::operator new(size);
+ void* 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;
namespace simgrid {
namespace mc {
+/************************************* Take Snapshot ************************************/
+/****************************************************************************************/
+
+void simgrid::mc::Snapshot::snapshot_regions(simgrid::mc::RemoteClient* process)
+{
+ snapshot_regions_.clear();
+
+ for (auto const& object_info : process->object_infos)
+ add_region(simgrid::mc::RegionType::Data, object_info.get(), object_info->start_rw,
+ object_info->end_rw - object_info->start_rw);
+
+ xbt_mheap_t heap = process->get_heap();
+ void* start_heap = heap->base;
+ void* end_heap = heap->breakval;
+
+ add_region(simgrid::mc::RegionType::Heap, nullptr, start_heap, (char*)end_heap - (char*)start_heap);
+ heap_bytes_used_ = mmalloc_get_bytes_used_remote(heap->heaplimit, process->get_malloc_info());
+}
+
+/** @brief Checks whether the variable is in scope for a given IP.
+ *
+ * A variable may be defined only from a given value of IP.
+ *
+ * @param var Variable description
+ * @param scope Scope description
+ * @param ip Instruction pointer
+ * @return true if the variable is valid
+ * */
+static bool valid_variable(simgrid::mc::Variable* var, simgrid::mc::Frame* scope, const void* ip)
+{
+ // The variable is not yet valid:
+ if (scope->range.begin() + var->start_scope > (std::uint64_t)ip)
+ return false;
+ else
+ return true;
+}
+
+static void fill_local_variables_values(mc_stack_frame_t stack_frame, simgrid::mc::Frame* scope,
+ std::vector<s_local_variable_t>& result)
+{
+ if (not scope || not scope->range.contain(stack_frame->ip))
+ return;
+
+ for (simgrid::mc::Variable& current_variable : scope->variables) {
+
+ if (not valid_variable(¤t_variable, scope, (void*)stack_frame->ip))
+ continue;
+
+ s_local_variable_t new_var;
+ new_var.subprogram = stack_frame->frame;
+ new_var.ip = stack_frame->ip;
+ new_var.name = current_variable.name;
+ new_var.type = current_variable.type;
+ new_var.address = nullptr;
+
+ if (current_variable.address != nullptr)
+ new_var.address = current_variable.address;
+ else if (not current_variable.location_list.empty()) {
+ simgrid::dwarf::Location location = simgrid::dwarf::resolve(
+ current_variable.location_list, current_variable.object_info, &(stack_frame->unw_cursor),
+ (void*)stack_frame->frame_base, &mc_model_checker->process());
+
+ if (not location.in_memory())
+ xbt_die("Cannot handle non-address variable");
+ new_var.address = location.address();
+
+ } else
+ xbt_die("No address");
+
+ result.push_back(std::move(new_var));
+ }
+
+ // Recursive processing of nested scopes:
+ for (simgrid::mc::Frame& nested_scope : scope->scopes)
+ fill_local_variables_values(stack_frame, &nested_scope, result);
+}
+
+static std::vector<s_local_variable_t> get_local_variables_values(std::vector<s_mc_stack_frame_t>& stack_frames)
+{
+ std::vector<s_local_variable_t> variables;
+ for (s_mc_stack_frame_t& stack_frame : stack_frames)
+ fill_local_variables_values(&stack_frame, stack_frame.frame, variables);
+ return variables;
+}
+
+static std::vector<s_mc_stack_frame_t> unwind_stack_frames(simgrid::mc::UnwindContext* stack_context)
+{
+ simgrid::mc::RemoteClient* process = &mc_model_checker->process();
+ std::vector<s_mc_stack_frame_t> result;
+
+ unw_cursor_t c = stack_context->cursor();
+
+ // TODO, check condition check (unw_init_local==0 means end of frame)
+
+ while (1) {
+
+ s_mc_stack_frame_t stack_frame;
+
+ stack_frame.unw_cursor = c;
+
+ unw_word_t ip;
+ unw_word_t sp;
+
+ unw_get_reg(&c, UNW_REG_IP, &ip);
+ unw_get_reg(&c, UNW_REG_SP, &sp);
+
+ stack_frame.ip = ip;
+ stack_frame.sp = sp;
+
+ // TODO, use real addresses in frame_t instead of fixing it here
+
+ simgrid::mc::Frame* frame = process->find_function(remote(ip));
+ stack_frame.frame = frame;
-Snapshot::Snapshot(RemoteClient* process, int _num_state)
+ if (frame) {
+ stack_frame.frame_name = frame->name;
+ stack_frame.frame_base = (unw_word_t)frame->frame_base(c);
+ } else {
+ stack_frame.frame_base = 0;
+ stack_frame.frame_name = std::string();
+ }
+
+ result.push_back(std::move(stack_frame));
+
+ /* Stop before context switch with maestro */
+ if (frame != nullptr && frame->name == "smx_ctx_wrapper")
+ break;
+
+ int ret = unw_step(&c);
+ if (ret == 0)
+ xbt_die("Unexpected end of stack.");
+ else if (ret < 0)
+ xbt_die("Error while unwinding stack");
+ }
+
+ xbt_assert(not result.empty(), "unw_init_local failed");
+
+ return result;
+}
+
+void simgrid::mc::Snapshot::snapshot_stacks(simgrid::mc::RemoteClient* process)
+{
+ for (auto const& stack : process->stack_areas()) {
+ s_mc_snapshot_stack_t st;
+
+ // Read the context from remote process:
+ unw_context_t context;
+ process->read_bytes(&context, sizeof(context), remote(stack.context));
+
+ st.context.initialize(process, &context);
+
+ st.stack_frames = unwind_stack_frames(&st.context);
+ st.local_variables = get_local_variables_values(st.stack_frames);
+
+ unw_word_t sp = st.stack_frames[0].sp;
+
+ stacks_.push_back(std::move(st));
+
+ size_t stack_size = (char*)stack.address + stack.size - (char*)sp;
+ stack_sizes_.push_back(stack_size);
+ }
+}
+
+static void snapshot_handle_ignore(simgrid::mc::Snapshot* snapshot)
+{
+ xbt_assert(snapshot->process());
+
+ // Copy the memory:
+ for (auto const& region : snapshot->process()->ignored_regions()) {
+ s_mc_snapshot_ignored_data_t ignored_data;
+ ignored_data.start = (void*)region.addr;
+ ignored_data.data.resize(region.size);
+ // TODO, we should do this once per privatization segment:
+ snapshot->process()->read_bytes(ignored_data.data.data(), region.size, remote(region.addr));
+ snapshot->ignored_data_.push_back(std::move(ignored_data));
+ }
+
+ // Zero the memory:
+ for (auto const& region : snapshot->process()->ignored_regions())
+ snapshot->process()->clear_bytes(remote(region.addr), region.size);
+}
+static void snapshot_ignore_restore(simgrid::mc::Snapshot* snapshot)
+{
+ for (auto const& ignored_data : snapshot->ignored_data_)
+ snapshot->process()->write_bytes(ignored_data.data.data(), ignored_data.data.size(), remote(ignored_data.start));
+}
+
+Snapshot::Snapshot(int num_state, RemoteClient* process)
: AddressSpace(process)
- , num_state_(_num_state)
+ , num_state_(num_state)
, heap_bytes_used_(0)
, enabled_processes_()
- , privatization_index_(0)
, hash_(0)
{
+ XBT_DEBUG("Taking snapshot %i", num_state);
+
+ for (auto const& p : process->actors())
+ enabled_processes_.insert(p.copy.get_buffer()->get_pid());
+
+ snapshot_handle_ignore(this);
+
+ /* Save the std heap and the writable mapped pages of libsimgrid and binary */
+ snapshot_regions(process);
+
+ to_ignore_ = process->ignored_heap();
+
+ if (_sg_mc_max_visited_states > 0 || not _sg_mc_property_file.get().empty()) {
+ snapshot_stacks(process);
+ if (_sg_mc_hash)
+ hash_ = simgrid::mc::hash(*this);
+ }
+
+ snapshot_ignore_restore(this);
}
-void Snapshot::add_region(RegionType type, ObjectInformation* object_info, void* start_addr, void* permanent_addr,
- std::size_t size)
+void Snapshot::add_region(RegionType type, ObjectInformation* object_info, void* start_addr, std::size_t size)
{
if (type == simgrid::mc::RegionType::Data)
xbt_assert(object_info, "Missing object info for object.");
else if (type == simgrid::mc::RegionType::Heap)
xbt_assert(not object_info, "Unexpected object info for heap region.");
- simgrid::mc::RegionSnapshot region;
-#if HAVE_SMPI
- const bool privatization_aware = object_info && mc_model_checker->process().privatized(*object_info);
- if (privatization_aware && MC_smpi_process_count())
- region = simgrid::mc::privatized_region(type, start_addr, permanent_addr, size);
- else
-#endif
- region = simgrid::mc::region(type, start_addr, permanent_addr, size);
-
- region.object_info(object_info);
- snapshot_regions_.push_back(std::unique_ptr<simgrid::mc::RegionSnapshot>(new RegionSnapshot(std::move(region))));
+ simgrid::mc::RegionSnapshot* region = new RegionSnapshot(type, start_addr, size);
+ region->object_info(object_info);
+ snapshot_regions_.push_back(std::unique_ptr<simgrid::mc::RegionSnapshot>(std::move(region)));
}
-const void* Snapshot::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index,
- ReadOptions options) const
+const void* Snapshot::read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, ReadOptions options) const
{
- RegionSnapshot* region = this->get_region((void*)address.address(), process_index);
+ RegionSnapshot* region = this->get_region((void*)address.address());
if (region) {
const void* res = MC_region_read(region, buffer, (void*)address.address(), size);
if (buffer == res || options & ReadOptions::lazy())
return buffer;
}
} else
- return this->process()->read_bytes(buffer, size, address, process_index, options);
+ return this->process()->read_bytes(buffer, size, address, options);
}
/** @brief Find the snapshoted region from a pointer
*
* @param addr Pointer
- * @param process_index rank requesting the region
* */
-RegionSnapshot* Snapshot::get_region(const void* addr, int process_index) const
+RegionSnapshot* Snapshot::get_region(const void* addr) const
{
size_t n = snapshot_regions_.size();
for (size_t i = 0; i != n; ++i) {
if (not(region && region->contain(simgrid::mc::remote(addr))))
continue;
- if (region->storage_type() == simgrid::mc::StorageType::Privatized) {
-#if HAVE_SMPI
- // Use the current process index of the snapshot:
- if (process_index == simgrid::mc::ProcessIndexDisabled)
- process_index = privatization_index_;
- xbt_assert(process_index >= 0, "Missing process index");
- xbt_assert(process_index < (int)region->privatized_data().size(), "Invalid process index");
-
- RegionSnapshot& priv_region = region->privatized_data()[process_index];
- xbt_assert(priv_region.contain(simgrid::mc::remote(addr)));
- return &priv_region;
-#else
- xbt_die("Privatized region in a non SMPI build (this should not happen)");
-#endif
- }
-
return region;
}
}
/** @brief Find the snapshoted region from a pointer, with a hinted_region */
-RegionSnapshot* Snapshot::get_region(const void* addr, int process_index, RegionSnapshot* hinted_region) const
+RegionSnapshot* Snapshot::get_region(const void* addr, RegionSnapshot* hinted_region) const
{
if (hinted_region->contain(simgrid::mc::remote(addr)))
return hinted_region;
else
- return get_region(addr, process_index);
+ return get_region(addr);
+}
+
+void Snapshot::restore(RemoteClient* process)
+{
+ XBT_DEBUG("Restore snapshot %i", num_state_);
+
+ // Restore regions
+ for (std::unique_ptr<simgrid::mc::RegionSnapshot> const& region : snapshot_regions_) {
+ if (region) // privatized variables are not snapshoted
+ region.get()->restore();
+ }
+
+ snapshot_ignore_restore(this);
+ process->clear_cache();
}
} // namespace mc