--- /dev/null
+/* Copyright (c) 2008-2018. The SimGrid Team.
+ * All rights reserved. */
+
+/* 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. */
+
+#ifndef SIMGRID_MC_ADDRESS_SPACE_H
+#define SIMGRID_MC_ADDRESS_SPACE_H
+
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+#include <type_traits>
+
+#include <string>
+#include <vector>
+
+#include "src/mc/mc_forward.hpp"
+#include "src/mc/remote/RemotePtr.hpp"
+
+namespace simgrid {
+namespace mc {
+
+/** Process index used when no process is available (SMPI privatization)
+ *
+ * The expected behavior is that if a process index is needed it will fail.
+ * */
+const int ProcessIndexMissing = -1;
+
+/** Process index used when we don't care about the process index (SMPI privatization)
+ * */
+const int ProcessIndexDisabled = -2;
+
+/** Constant used when any process will do (SMPI privatization)
+ *
+ * Note: This is is index of the first process.
+ */
+const int ProcessIndexAny = 0;
+
+/** Options for read operations
+ *
+ * This is a set of flags managed with bitwise operators. Only the
+ * meaningful operations are defined: addition, conversions to/from
+ * integers are not allowed.
+ */
+class ReadOptions {
+ std::uint32_t value_;
+ constexpr explicit ReadOptions(std::uint32_t value) : value_(value) {}
+public:
+ constexpr ReadOptions() : value_(0) {}
+
+ explicit constexpr operator bool() const { return value_ != 0; }
+ constexpr bool operator!() const { return value_ == 0; }
+
+ constexpr ReadOptions operator|(ReadOptions const& that) const
+ {
+ return ReadOptions(value_ | that.value_);
+ }
+ constexpr ReadOptions operator&(ReadOptions const& that) const
+ {
+ return ReadOptions(value_ & that.value_);
+ }
+ constexpr ReadOptions operator^(ReadOptions const& that) const
+ {
+ return ReadOptions(value_ ^ that.value_);
+ }
+ constexpr ReadOptions operator~() const
+ {
+ return ReadOptions(~value_);
+ }
+
+ ReadOptions& operator|=(ReadOptions const& that)
+ {
+ value_ |= that.value_;
+ return *this;
+ }
+ ReadOptions& operator&=(ReadOptions const& that)
+ {
+ value_ &= that.value_;
+ return *this;
+ }
+ ReadOptions& operator^=(ReadOptions const& that)
+ {
+ value_ &= that.value_;
+ return *this;
+ }
+
+ /** Copy the data to the given buffer */
+ static constexpr ReadOptions none() { return ReadOptions(0); }
+
+ /** Allows to return a pointer to another buffer where the data is
+ * available instead of copying the data into the buffer
+ */
+ static constexpr ReadOptions lazy() { return ReadOptions(1); }
+};
+
+/** A given state of a given process (abstract base class)
+ *
+ * Currently, this might either be:
+ *
+ * * the current state of an existing process;
+ *
+ * * a snapshot.
+ *
+ * In order to support SMPI privatization, the can read the memory from the
+ * context of a given SMPI process: if specified, the code reads data from the
+ * correct SMPI privatization VMA.
+ */
+class AddressSpace {
+private:
+ RemoteClient* process_;
+
+public:
+ explicit AddressSpace(RemoteClient* process) : process_(process) {}
+ virtual ~AddressSpace() = default;
+
+ /** The process of this address space
+ *
+ * This is where we can get debug informations, memory layout, etc.
+ */
+ simgrid::mc::RemoteClient* process() const { return process_; }
+
+ /** Read data from the address space
+ *
+ * @param buffer target buffer for the data
+ * @param size number of bytes to read
+ * @param address remote source address of the data
+ * @param process_index which process (used for SMPI privatization)
+ * @param options
+ */
+ virtual const void* read_bytes(void* buffer, std::size_t size,
+ RemotePtr<void> address, int process_index = ProcessIndexAny,
+ ReadOptions options = ReadOptions::none()) const = 0;
+
+ /** Read a given data structure from the address space */
+ template<class T> inline
+ void read(T *buffer, RemotePtr<T> ptr, int process_index = ProcessIndexAny) const
+ {
+ this->read_bytes(buffer, sizeof(T), ptr, process_index);
+ }
+
+ template<class T> inline
+ void read(Remote<T>& buffer, RemotePtr<T> ptr, int process_index = ProcessIndexAny) const
+ {
+ this->read_bytes(buffer.getBuffer(), sizeof(T), ptr, process_index);
+ }
+
+ /** Read a given data structure from the addres space
+ *
+ * This version returns by value.
+ */
+ template<class T> inline
+ Remote<T> read(RemotePtr<T> ptr, int process_index = ProcessIndexMissing) const
+ {
+ Remote<T> res;
+ this->read_bytes(&res, sizeof(T), ptr, process_index);
+ return res;
+ }
+
+ /** Read a string of known size */
+ std::string read_string(RemotePtr<char> address, std::size_t len) const
+ {
+ std::string res;
+ res.resize(len);
+ this->read_bytes(&res[0], len, address);
+ return res;
+ }
+
+};
+
+}
+}
+
+#endif
--- /dev/null
+/* Copyright (c) 2007-2018. The SimGrid Team. All rights reserved. */
+
+/* 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 <cstdint>
+
+#include <vector>
+
+#include "xbt/asserts.h"
+#include "xbt/misc.h"
+
+#include "src/mc/AddressSpace.hpp"
+#include "src/mc/ChunkedData.hpp"
+#include "src/mc/PageStore.hpp"
+
+namespace simgrid {
+namespace mc {
+
+/** Take a per-page snapshot of a region
+ *
+ * @param addr The start of the region (must be at the beginning of a page)
+ * @param page_count Number of pages of the region
+ * @return Snapshot page numbers of this new snapshot
+ */
+ChunkedData::ChunkedData(PageStore& store, AddressSpace& as,
+ RemotePtr<void> addr, std::size_t page_count)
+{
+ store_ = &store;
+ this->pagenos_.resize(page_count);
+ std::vector<char> buffer(xbt_pagesize);
+
+ for (size_t i = 0; i != page_count; ++i) {
+
+ RemotePtr<void> page = remote((void*)
+ simgrid::mc::mmu::join(i, addr.address()));
+ xbt_assert(simgrid::mc::mmu::split(page.address()).second == 0,
+ "Not at the beginning of a page");
+
+ /* Adding another copy (and a syscall) will probably slow things a lot.
+ TODO, optimize this somehow (at least by grouping the syscalls)
+ if needed. Either:
+ - reduce the number of syscalls
+ - let the application snapshot itself
+ - move the segments in shared memory (this will break `fork` however)
+ */
+
+ as.read_bytes(buffer.data(), xbt_pagesize, page, simgrid::mc::ProcessIndexDisabled);
+
+ pagenos_[i] = store_->store_page(buffer.data());
+
+ }
+}
+
+}
+}
--- /dev/null
+/* Copyright (c) 2014-2018. The SimGrid Team. All rights reserved. */
+
+/* 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. */
+
+#ifndef SIMGRID_MC_CHUNKED_DATA_HPP
+#define SIMGRID_MC_CHUNKED_DATA_HPP
+
+#include <cstddef>
+#include <cstdint>
+
+#include <utility>
+#include <vector>
+
+#include "src/mc/mc_forward.hpp"
+#include "src/mc/PageStore.hpp"
+
+namespace simgrid {
+namespace mc {
+
+/** A byte-string represented as a sequence of chunks from a PageStore
+ *
+ * In order to save memory when taking memory snapshots, a given byte-string
+ * is split in fixed-size chunks. Identical chunks (either from the same
+ * snapshot or more probably from different snpashots) share the same memory
+ * storage.
+ *
+ * Thus a chunked is represented as a sequence of indices of each chunk.
+ */
+class ChunkedData {
+ /** This is where we store the chunks */
+ PageStore* store_ = nullptr;
+ /** Indices of the chunks in the `PageStore` */
+ std::vector<std::size_t> pagenos_;
+public:
+
+ ChunkedData() = default;
+ void clear()
+ {
+ for (std::size_t const& pageno : pagenos_)
+ store_->unref_page(pageno);
+ pagenos_.clear();
+ }
+ ~ChunkedData()
+ {
+ clear();
+ }
+
+ // Copy and move
+ ChunkedData(ChunkedData const& that)
+ : store_ (that.store_)
+ , pagenos_(that.pagenos_)
+ {
+ for (std::size_t const& pageno : pagenos_)
+ store_->ref_page(pageno);
+ }
+ ChunkedData(ChunkedData&& that)
+ : store_(that.store_)
+ , pagenos_(std::move(that.pagenos_))
+ {
+ that.store_ = nullptr;
+ that.pagenos_.clear();
+ }
+ ChunkedData& operator=(ChunkedData const& that)
+ {
+ this->clear();
+ store_ = that.store_;
+ pagenos_ = that.pagenos_;
+ for (std::size_t const& pageno : pagenos_)
+ store_->ref_page(pageno);
+ return *this;
+ }
+ ChunkedData& operator=(ChunkedData && that)
+ {
+ this->clear();
+ store_ = that.store_;
+ that.store_ = nullptr;
+ pagenos_ = std::move(that.pagenos_);
+ that.pagenos_.clear();
+ return *this;
+ }
+
+ /** How many pages are used */
+ std::size_t page_count() const { return pagenos_.size(); }
+
+ /** Get a chunk index */
+ std::size_t pageno(std::size_t i) const { return pagenos_[i]; }
+
+ /** Get a view of the chunk indices */
+ const std::size_t* pagenos() const { return pagenos_.data(); }
+
+ /** Get a a pointer to a chunk */
+ const void* page(std::size_t i) const
+ {
+ return store_->get_page(pagenos_[i]);
+ }
+
+ ChunkedData(PageStore& store, AddressSpace& as,
+ RemotePtr<void> addr, std::size_t page_count);
+};
+
+}
+}
+
+#endif
--- /dev/null
+/* Copyright (c) 2015-2018. The SimGrid Team.
+ * All rights reserved. */
+
+/* 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 <cstring> // memcpy, memcmp
+#include <unistd.h>
+
+#include <sys/mman.h>
+#ifdef __FreeBSD__
+# define MAP_POPULATE MAP_PREFAULT_READ
+#endif
+
+#include "xbt/base.h"
+#include "xbt/log.h"
+#include "xbt/sysdep.h"
+
+#include "src/internal_config.h"
+
+#include "src/mc/PageStore.hpp"
+
+#include "src/mc/mc_mmu.hpp"
+
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_page_snapshot, mc, "Logging specific to mc_page_snapshot");
+
+namespace simgrid {
+namespace mc {
+
+/** @brief Compute a hash for the given memory page
+ *
+ * The page is used before inserting the page in the page store
+ * in order to find duplicate of this page in the page store.
+ *
+ * @param data Memory page
+ * @return hash off the page
+ */
+static XBT_ALWAYS_INLINE PageStore::hash_type mc_hash_page(const void* data)
+{
+ const std::uint64_t* values = (const uint64_t*) data;
+ std::size_t n = xbt_pagesize / sizeof(uint64_t);
+
+ // This djb2:
+ std::uint64_t hash = 5381;
+ for (std::size_t i = 0; i != n; ++i)
+ hash = ((hash << 5) + hash) + values[i];
+ return hash;
+}
+
+// ***** snapshot_page_manager
+
+PageStore::PageStore(size_t size) : memory_(nullptr), capacity_(size), top_index_(0)
+{
+ // Using mmap in order to be able to expand the region by relocating it somewhere else in the virtual memory space:
+ void* memory = ::mmap(nullptr, size << xbt_pagebits, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_POPULATE, -1, 0);
+ if (memory == MAP_FAILED)
+ xbt_die("Could not mmap initial snapshot pages.");
+
+ this->top_index_ = 0;
+ this->memory_ = memory;
+ this->page_counts_.resize(size);
+}
+
+PageStore::~PageStore()
+{
+ ::munmap(this->memory_, this->capacity_ << xbt_pagebits);
+}
+
+void PageStore::resize(std::size_t size)
+{
+ size_t old_bytesize = this->capacity_ << xbt_pagebits;
+ size_t new_bytesize = size << xbt_pagebits;
+ void *new_memory;
+
+ // Expand the memory region by moving it into another
+ // virtual memory address if necessary:
+#if HAVE_MREMAP
+ new_memory = mremap(this->memory_, old_bytesize, new_bytesize, MREMAP_MAYMOVE);
+ if (new_memory == MAP_FAILED)
+ xbt_die("Could not mremap snapshot pages.");
+#else
+ if (new_bytesize > old_bytesize) {
+ // Grow: first try to add new space after current map
+ new_memory = mmap((char *)this->memory_ + old_bytesize,
+ new_bytesize-old_bytesize,
+ PROT_READ|PROT_WRITE,
+ MAP_PRIVATE|MAP_ANONYMOUS|MAP_POPULATE,
+ -1, 0);
+ if (new_memory == MAP_FAILED)
+ xbt_die("Could not mremap snapshot pages.");
+ // Check if expanding worked
+ if (new_memory != (char *)this->memory_ + old_bytesize) {
+ // New memory segment could not be put at the end of this->memory_,
+ // so cancel this one and try to rellocate everything and copy data
+ munmap(new_memory, new_bytesize-old_bytesize);
+ new_memory = mmap(nullptr,
+ new_bytesize,
+ PROT_READ|PROT_WRITE,
+ MAP_PRIVATE|MAP_ANONYMOUS|MAP_POPULATE,
+ -1, 0);
+ if (new_memory == MAP_FAILED)
+ xbt_die("Could not mremap snapshot pages.");
+ memcpy(new_memory, this->memory_, old_bytesize);
+ munmap(this->memory_, old_bytesize);
+ }
+ }
+ else {
+ // We don't have functions to shrink a mapping, so leave memory as
+ // it is for now
+ new_memory = this->memory_;
+ }
+#endif
+
+ this->capacity_ = size;
+ this->memory_ = new_memory;
+ this->page_counts_.resize(size, 0);
+}
+
+/** Allocate a free page
+ *
+ * @return index of the free page
+ */
+std::size_t PageStore::alloc_page()
+{
+ if (this->free_pages_.empty()) {
+
+ // Expand the region:
+ if (this->top_index_ == this->capacity_)
+ // All the pages are allocated, we need add more pages:
+ this->resize(2 * this->capacity_);
+
+ // Use a page from the top:
+ return this->top_index_++;
+
+ } else {
+
+ // Use a page from free_pages_ (inside of the region):
+ size_t res = this->free_pages_[this->free_pages_.size() - 1];
+ this->free_pages_.pop_back();
+ return res;
+ }
+}
+
+void PageStore::remove_page(std::size_t pageno)
+{
+ this->free_pages_.push_back(pageno);
+ const void* page = this->get_page(pageno);
+ hash_type hash = mc_hash_page(page);
+ this->hash_index_[hash].erase(pageno);
+}
+
+/** Store a page in memory */
+std::size_t PageStore::store_page(void* page)
+{
+ xbt_assert(top_index_ <= this->capacity_, "top_index is not consistent");
+
+ // First, we check if a page with the same content is already in the page store:
+ // 1. compute the hash of the page
+ // 2. find pages with the same hash using `hash_index_`
+ // 3. find a page with the same content
+ hash_type hash = mc_hash_page(page);
+
+ // Try to find a duplicate in set of pages with the same hash:
+ page_set_type& page_set = this->hash_index_[hash];
+ for (size_t const& pageno : page_set) {
+ const void* snapshot_page = this->get_page(pageno);
+ if (memcmp(page, snapshot_page, xbt_pagesize) == 0) {
+
+ // If a page with the same content is already in the page store it's reused and its refcount is incremented.
+ page_counts_[pageno]++;
+ return pageno;
+
+ }
+ }
+
+ // Otherwise, a new page is allocated in the page store and the content of the page is `memcpy()`-ed to this new page.
+ std::size_t pageno = alloc_page();
+ xbt_assert(this->page_counts_[pageno]==0, "Allocated page is already used");
+ void* snapshot_page = (void*) this->get_page(pageno);
+ memcpy(snapshot_page, page, xbt_pagesize);
+ page_set.insert(pageno);
+ page_counts_[pageno]++;
+ return pageno;
+}
+
+}
+}
+
+#ifdef SIMGRID_TEST
+
+#include <cstring>
+#include <cstdint>
+
+#include <unistd.h>
+#include <sys/mman.h>
+
+#include <memory>
+
+#include "src/mc/PageStore.hpp"
+
+static int value = 0;
+
+static void new_content(void* data, std::size_t size)
+{
+ ::memset(data, ++value, size);
+}
+
+static void* getpage()
+{
+ return mmap(nullptr, getpagesize(), PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+}
+
+XBT_TEST_SUITE("mc_page_store", "Page store");
+
+XBT_TEST_UNIT("base", test_mc_page_store, "Test adding/removing pages in the store")
+{
+ using simgrid::mc::PageStore;
+
+ xbt_test_add("Init");
+ std::size_t pagesize = (size_t) getpagesize();
+ std::unique_ptr<PageStore> store = std::unique_ptr<PageStore>(new simgrid::mc::PageStore(500));
+ void* data = getpage();
+ xbt_test_assert(store->size()==0, "Bad size");
+
+ xbt_test_add("Store the page once");
+ new_content(data, pagesize);
+ size_t pageno1 = store->store_page(data);
+ xbt_test_assert(store->get_ref(pageno1)==1, "Bad refcount");
+ const void* copy = store->get_page(pageno1);
+ xbt_test_assert(::memcmp(data, copy, pagesize)==0, "Page data should be the same");
+ xbt_test_assert(store->size()==1, "Bad size");
+
+ xbt_test_add("Store the same page again");
+ size_t pageno2 = store->store_page(data);
+ xbt_test_assert(pageno1==pageno2, "Page should be the same");
+ xbt_test_assert(store->get_ref(pageno1)==2, "Bad refcount");
+ xbt_test_assert(store->size()==1, "Bad size");
+
+ xbt_test_add("Store a new page");
+ new_content(data, pagesize);
+ size_t pageno3 = store->store_page(data);
+ xbt_test_assert(pageno1 != pageno3, "New page should be different");
+ xbt_test_assert(store->size()==2, "Bad size");
+
+ xbt_test_add("Unref pages");
+ store->unref_page(pageno1);
+ xbt_assert(store->get_ref(pageno1)==1, "Bad refcount");
+ xbt_assert(store->size()==2, "Bad size");
+ store->unref_page(pageno2);
+ xbt_test_assert(store->size()==1, "Bad size");
+
+ xbt_test_add("Reallocate page");
+ new_content(data, pagesize);
+ size_t pageno4 = store->store_page(data);
+ xbt_test_assert(pageno1 == pageno4, "Page was not reused");
+ xbt_test_assert(store->get_ref(pageno4)==1, "Bad refcount");
+ xbt_test_assert(store->size()==2, "Bad size");
+}
+
+#endif /* SIMGRID_TEST */
--- /dev/null
+/* Copyright (c) 2015-2018. The SimGrid Team.
+ * All rights reserved. */
+
+/* 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. */
+
+#ifndef SIMGRID_MC_PAGESTORE_HPP
+#define SIMGRID_MC_PAGESTORE_HPP
+
+#include <cstdint>
+#include <vector>
+
+#include <unordered_map>
+#include <unordered_set>
+
+#include "xbt/base.h"
+
+#include "src/mc/mc_forward.hpp"
+#include "src/mc/mc_mmu.hpp"
+
+namespace simgrid {
+namespace mc {
+
+/** @brief Storage for snapshot memory pages
+ *
+ * The first (lower) layer of the per-page snapshot mechanism is a page store:
+ * its responsibility is to store immutable sharable reference-counted memory
+ * pages independently of the snapshotting logic. Snapshot management and
+ * representation is handled to an higher layer. READMORE
+ *
+ * Data structure:
+ *
+ * * A pointer (`memory_`) to a (currently anonymous) `mmap()`ed memory
+ * region holding the memory pages (the address of the first page).
+ *
+ * We want to keep this memory region aligned on the memory pages (so
+ * that we might be able to create non-linear memory mappings on those
+ * pages in the future) and be able to expand it without coyping the
+ * data (there will be a lot of pages here): we will be able to
+ * efficiently expand the memory mapping using `mremap()`, moving it
+ * to another virtual address if necessary.
+ *
+ * Because we will move this memory mapping on the virtual address
+ * space, only the index of the page will be stored in the snapshots
+ * and the page will always be looked up by going through `memory`:
+ *
+ * void* page = (char*) page_store->memory + page_index << pagebits;
+ *
+ * * The number of pages mapped in virtual memory (`capacity_`). Once all
+ * those pages are used, we need to expand the page store with
+ * `mremap()`.
+ *
+ * * A reference count for each memory page `page_counts_`. Each time a
+ * snapshot references a page, the counter is incremented. If a
+ * snapshot is freed, the reference count is decremented. When the
+ * reference count, of a page reaches 0 it is added to a list of available
+ * pages (`free_pages_`).
+ *
+ * * A list of free pages `free_pages_` which can be reused. This avoids having
+ * to scan the reference count list to find a free page.
+ *
+ * * When we are expanding the memory map we do not want to add thousand of page
+ * to the `free_pages_` list and remove them just afterwards. The `top_index_`
+ * field is an index after which all pages are free and are not in the `free_pages_`
+ * list.
+ *
+ * * When we are adding a page, we need to check if a page with the same
+ * content is already in the page store in order to reuse it. For this
+ * reason, we maintain an index (`hash_index_`) mapping the hash of a
+ * page to the list of page indices with this hash.
+ * We use a fast (non cryptographic) hash so there may be conflicts:
+ * we must be able to store multiple indices for the same hash.
+ *
+ */
+class PageStore {
+public: // Types
+ typedef std::uint64_t hash_type;
+
+private:
+ // Types
+ // We are using a cheap hash to index a page.
+ // We should expect collision and we need to associate multiple page indices
+ // to the same hash.
+ typedef std::unordered_set<std::size_t> page_set_type;
+ typedef std::unordered_map<hash_type, page_set_type> pages_map_type;
+
+ // Fields:
+ /** First page */
+ void* memory_;
+ /** Number of available pages in virtual memory */
+ std::size_t capacity_;
+ /** Top of the used pages (index of the next available page) */
+ std::size_t top_index_;
+ /** Page reference count */
+ std::vector<std::uint64_t> page_counts_;
+ /** Index of available pages before the top */
+ std::vector<std::size_t> free_pages_;
+ /** Index from page hash to page index */
+ pages_map_type hash_index_;
+
+ // Methods
+ void resize(std::size_t size);
+ std::size_t alloc_page();
+ void remove_page(std::size_t pageno);
+
+public:
+ // Constructors
+ PageStore(PageStore const&) = delete;
+ PageStore& operator=(PageStore const&) = delete;
+ explicit PageStore(std::size_t size);
+ ~PageStore();
+
+ // Methods
+
+ /** @brief Decrement the reference count for a given page
+ *
+ * Decrement the reference count of this page. Used when a snapshot is destroyed.
+ *
+ * If the reference count reaches zero, the page is recycled:
+ * it is added to the `free_pages_` list and removed from the `hash_index_`.
+ *
+ * */
+ void unref_page(std::size_t pageno);
+
+ /** @brief Increment the refcount for a given page
+ *
+ * This method used to increase a reference count of a page if we know
+ * that the content of a page is the same as a page already in the page
+ * store.
+ *
+ * This will be the case if a page if soft clean: we know that is has not
+ * changed since the previous cnapshot/restoration and we can avoid
+ * hashing the page, comparing byte-per-byte to candidates.
+ * */
+ void ref_page(size_t pageno);
+
+ /** @brief Store a page in the page store */
+ std::size_t store_page(void* page);
+
+ /** @brief Get a page from its page number
+ *
+ * @param pageno Number of the memory page in the store
+ * @return Start of the page
+ */
+ const void* get_page(std::size_t pageno) const;
+
+ // Debug/test methods
+
+ /** @brief Get the number of references for a page */
+ std::size_t get_ref(std::size_t pageno);
+
+ /** @brief Get the number of used pages */
+ std::size_t size();
+
+ /** @brief Get the capacity of the page store
+ *
+ * The capacity is expanded by a system call (mremap).
+ * */
+ std::size_t capacity();
+
+};
+
+XBT_ALWAYS_INLINE void PageStore::unref_page(std::size_t pageno)
+{
+ if ((--this->page_counts_[pageno]) == 0)
+ this->remove_page(pageno);
+}
+
+XBT_ALWAYS_INLINE void PageStore::ref_page(size_t pageno)
+{
+ ++this->page_counts_[pageno];
+}
+
+XBT_ALWAYS_INLINE const void* PageStore::get_page(std::size_t pageno) const
+{
+ return (void*) simgrid::mc::mmu::join(pageno, (std::uintptr_t) this->memory_);
+}
+
+XBT_ALWAYS_INLINE std::size_t PageStore::get_ref(std::size_t pageno)
+{
+ return this->page_counts_[pageno];
+}
+
+XBT_ALWAYS_INLINE std::size_t PageStore::size()
+{
+ return this->top_index_ - this->free_pages_.size();
+}
+
+XBT_ALWAYS_INLINE std::size_t PageStore::capacity()
+{
+ return this->capacity_;
+}
+
+}
+}
+
+#endif
--- /dev/null
+/* Copyright (c) 2007-2018. The SimGrid Team.
+ * All rights reserved. */
+
+/* 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 <cstdlib>
+
+#include <sys/mman.h>
+#ifdef __FreeBSD__
+# define MAP_POPULATE MAP_PREFAULT_READ
+#endif
+
+#include "mc/mc.h"
+#include "src/mc/mc_config.hpp"
+#include "src/mc/mc_snapshot.hpp"
+
+#include "src/mc/ChunkedData.hpp"
+#include "src/mc/RegionSnapshot.hpp"
+
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_RegionSnaphot, mc,
+ "Logging specific to region snapshots");
+
+namespace simgrid {
+namespace mc {
+
+static inline
+const char* to_cstr(RegionType region)
+{
+ switch (region) {
+ case RegionType::Unknown:
+ return "unknown";
+ case RegionType::Heap:
+ return "Heap";
+ case RegionType::Data:
+ return "Data";
+ default:
+ return "?";
+ }
+}
+
+Buffer::Buffer(std::size_t size, Type type) : size_(size), type_(type)
+{
+ switch(type_) {
+ case Type::Malloc:
+ data_ = ::operator new(size_);
+ break;
+ case Type::Mmap:
+ data_ = ::mmap(nullptr, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_POPULATE, -1, 0);
+ if (data_ == MAP_FAILED) {
+ data_ = nullptr;
+ size_ = 0;
+ type_ = Type::Malloc;
+ throw std::bad_alloc();
+ }
+ break;
+ default:
+ abort();
+ }
+}
+
+void Buffer::clear() noexcept
+{
+ switch(type_) {
+ case Type::Malloc:
+ ::operator delete(data_);
+ break;
+ case Type::Mmap:
+ if (munmap(data_, size_) != 0)
+ abort();
+ break;
+ default:
+ abort();
+ }
+ data_ = nullptr;
+ size_ = 0;
+ type_ = Type::Malloc;
+}
+
+RegionSnapshot dense_region(
+ RegionType region_type,
+ void *start_addr, void* permanent_addr, size_t size)
+{
+ // When KSM support is enables, we allocate memory using mmap:
+ // * we don't want to advise bits of the heap as mergable
+ // * mmap gives data aligned on page boundaries which is merge friendly
+ simgrid::mc::Buffer data;
+ if (_sg_mc_ksm)
+ data = Buffer::mmap(size);
+ else
+ data = Buffer::malloc(size);
+
+ mc_model_checker->process().read_bytes(data.get(), size,
+ remote(permanent_addr),
+ simgrid::mc::ProcessIndexDisabled);
+
+#ifdef __linux__
+ if (_sg_mc_ksm)
+ // Mark the region as mergeable *after* we have written into it.
+ // Trying to merge them before is useless/counterproductive.
+ madvise(data.get(), size, MADV_MERGEABLE);
+#endif
+
+ simgrid::mc::RegionSnapshot region(
+ region_type, start_addr, permanent_addr, size);
+ region.flat_data(std::move(data));
+
+ XBT_DEBUG("New region : type : %s, data : %p (real addr %p), size : %zu",
+ to_cstr(region_type), region.flat_data().get(), permanent_addr, size);
+ return region;
+}
+
+/** @brief Take a snapshot of a given region
+ *
+ * @param type
+ * @param start_addr Address of the region in the simulated process
+ * @param permanent_addr Permanent address of this data (for privatized variables, this is the virtual address of the privatized mapping)
+ * @param size Size of the data*
+ */
+RegionSnapshot region(
+ RegionType type, void *start_addr, void* permanent_addr, size_t size)
+{
+ if (_sg_mc_sparse_checkpoint)
+ return sparse_region(type, start_addr, permanent_addr, size);
+ else
+ return dense_region(type, start_addr, permanent_addr, size);
+}
+
+RegionSnapshot sparse_region(RegionType region_type,
+ void *start_addr, void* permanent_addr, size_t size)
+{
+ simgrid::mc::RemoteClient* process = &mc_model_checker->process();
+ assert(process != nullptr);
+
+ xbt_assert((((uintptr_t)start_addr) & (xbt_pagesize-1)) == 0,
+ "Not at the beginning of a page");
+ xbt_assert((((uintptr_t)permanent_addr) & (xbt_pagesize-1)) == 0,
+ "Not at the beginning of a page");
+ size_t page_count = simgrid::mc::mmu::chunkCount(size);
+
+ simgrid::mc::ChunkedData page_data(mc_model_checker->page_store(), *process, RemotePtr<void>(permanent_addr),
+ page_count);
+
+ simgrid::mc::RegionSnapshot region(
+ region_type, start_addr, permanent_addr, size);
+ region.page_data(std::move(page_data));
+ return region;
+}
+
+}
+}
--- /dev/null
+/* Copyright (c) 2007-2018. The SimGrid Team. All rights reserved. */
+
+/* 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. */
+
+#ifndef SIMGRID_MC_REGION_SNAPSHOT_HPP
+#define SIMGRID_MC_REGION_SNAPSHOT_HPP
+
+#include <cstddef>
+#include <utility>
+
+#include <memory>
+#include <vector>
+
+#include "xbt/base.h"
+
+#include "src/mc/AddressSpace.hpp"
+#include "src/mc/ChunkedData.hpp"
+#include "src/mc/PageStore.hpp"
+#include "src/mc/remote/RemotePtr.hpp"
+
+namespace simgrid {
+namespace mc {
+
+enum class RegionType {
+ Unknown = 0,
+ Heap = 1,
+ Data = 2
+};
+
+enum class StorageType {
+ NoData = 0,
+ Flat = 1,
+ Chunked = 2,
+ Privatized = 3
+};
+
+class Buffer {
+private:
+ enum class Type {
+ Malloc,
+ Mmap
+ };
+ void* data_ = nullptr;
+ std::size_t size_;
+ Type type_ = Type::Malloc;
+
+ Buffer(std::size_t size, Type type = Type::Malloc);
+ Buffer(void* data, std::size_t size, Type type = Type::Malloc) :
+ data_(data), size_(size), type_(type) {}
+public:
+ Buffer() = default;
+ void clear() noexcept;
+ ~Buffer() noexcept { clear(); }
+
+ static Buffer malloc(std::size_t size)
+ {
+ return Buffer(size, Type::Malloc);
+ }
+ static Buffer mmap(std::size_t size)
+ {
+ return Buffer(size, Type::Mmap);
+ }
+
+ // No copy
+ Buffer(Buffer const& buffer) = delete;
+ Buffer& operator=(Buffer const& buffer) = delete;
+
+ // Move
+ Buffer(Buffer&& that) noexcept
+ : data_(that.data_), size_(that.size_), type_(that.type_)
+ {
+ that.data_ = nullptr;
+ that.size_ = 0;
+ that.type_ = Type::Malloc;
+ }
+ Buffer& operator=(Buffer&& that) noexcept
+ {
+ clear();
+ data_ = that.data_;
+ size_ = that.size_;
+ type_ = that.type_;
+ that.data_ = nullptr;
+ that.size_ = 0;
+ that.type_ = Type::Malloc;
+ return *this;
+ }
+
+ void* get() { return data_; }
+ const void* get() const { return data_; }
+ std::size_t size() const { return size_; }
+};
+
+/** A copy/snapshot of a given memory region
+ *
+ * Different types of region snapshot storage types exist:
+ *
+ * * flat/dense snapshots are a simple copy of the region;
+ *
+ * * sparse/per-page snapshots are snaapshots which shared
+ * identical pages.
+ *
+ * * privatized (SMPI global variable privatization).
+ *
+ * This is handled with a variant based approach:
+ *
+ * * `storage_type` identified the type of storage;
+ *
+ * * an anonymous enum is used to distinguish the relevant types for
+ * each type.
+ */
+class RegionSnapshot {
+public:
+ static const RegionType UnknownRegion = RegionType::Unknown;
+ static const RegionType HeapRegion = RegionType::Heap;
+ static const RegionType DataRegion = RegionType::Data;
+private:
+ RegionType region_type_;
+ StorageType storage_type_;
+ simgrid::mc::ObjectInformation* object_info_;
+
+ /** @brief Virtual address of the region in the simulated process */
+ void *start_addr_;
+
+ /** @brief Size of the data region in bytes */
+ std::size_t size_;
+
+ /** @brief Permanent virtual address of the region
+ *
+ * This is usually the same address as the simuilated process address.
+ * However, when using SMPI privatization of global variables,
+ * each SMPI process has its own set of global variables stored
+ * at a different virtual address. The scheduler maps those region
+ * on the region of the global variables.
+ *
+ * */
+ void *permanent_addr_;
+
+ Buffer flat_data_;
+ ChunkedData page_numbers_;
+ std::vector<RegionSnapshot> privatized_regions_;
+public:
+ RegionSnapshot() :
+ region_type_(UnknownRegion),
+ storage_type_(StorageType::NoData),
+ object_info_(nullptr),
+ start_addr_(nullptr),
+ size_(0),
+ permanent_addr_(nullptr)
+ {}
+ RegionSnapshot(RegionType type, void *start_addr, void* permanent_addr, size_t size) :
+ region_type_(type),
+ storage_type_(StorageType::NoData),
+ object_info_(nullptr),
+ start_addr_(start_addr),
+ size_(size),
+ permanent_addr_(permanent_addr)
+ {}
+ ~RegionSnapshot() = default;
+ RegionSnapshot(RegionSnapshot const&) = default;
+ RegionSnapshot& operator=(RegionSnapshot const&) = default;
+ RegionSnapshot(RegionSnapshot&& that)
+ : region_type_(that.region_type_)
+ , storage_type_(that.storage_type_)
+ , object_info_(that.object_info_)
+ , start_addr_(that.start_addr_)
+ , size_(that.size_)
+ , permanent_addr_(that.permanent_addr_)
+ , flat_data_(std::move(that.flat_data_))
+ , page_numbers_(std::move(that.page_numbers_))
+ , privatized_regions_(std::move(that.privatized_regions_))
+ {
+ that.clear();
+ }
+ RegionSnapshot& operator=(RegionSnapshot&& that)
+ {
+ region_type_ = that.region_type_;
+ storage_type_ = that.storage_type_;
+ object_info_ = that.object_info_;
+ start_addr_ = that.start_addr_;
+ size_ = that.size_;
+ permanent_addr_ = that.permanent_addr_;
+ flat_data_ = std::move(that.flat_data_);
+ page_numbers_ = std::move(that.page_numbers_);
+ privatized_regions_ = std::move(that.privatized_regions_);
+ that.clear();
+ return *this;
+ }
+
+ // Data
+
+ void clear()
+ {
+ region_type_ = UnknownRegion;
+ storage_type_ = StorageType::NoData;
+ privatized_regions_.clear();
+ page_numbers_.clear();
+ flat_data_.clear();
+ object_info_ = nullptr;
+ start_addr_ = nullptr;
+ size_ = 0;
+ permanent_addr_ = nullptr;
+ }
+
+ void clear_data()
+ {
+ storage_type_ = StorageType::NoData;
+ flat_data_.clear();
+ page_numbers_.clear();
+ privatized_regions_.clear();
+ }
+
+ void flat_data(Buffer data)
+ {
+ storage_type_ = StorageType::Flat;
+ flat_data_ = std::move(data);
+ page_numbers_.clear();
+ privatized_regions_.clear();
+ }
+ const Buffer& flat_data() const { return flat_data_; }
+ Buffer& flat_data() { return flat_data_; }
+
+ void page_data(ChunkedData page_data)
+ {
+ storage_type_ = StorageType::Chunked;
+ flat_data_.clear();
+ page_numbers_ = std::move(page_data);
+ privatized_regions_.clear();
+ }
+ ChunkedData const& page_data() const { return page_numbers_; }
+
+ void privatized_data(std::vector<RegionSnapshot> data)
+ {
+ storage_type_ = StorageType::Privatized;
+ flat_data_.clear();
+ page_numbers_.clear();
+ privatized_regions_ = std::move(data);
+ }
+ std::vector<RegionSnapshot> const& privatized_data() const
+ {
+ return privatized_regions_;
+ }
+ std::vector<RegionSnapshot>& privatized_data()
+ {
+ return privatized_regions_;
+ }
+
+ simgrid::mc::ObjectInformation* object_info() const { return object_info_; }
+ void object_info(simgrid::mc::ObjectInformation* info) { object_info_ = info; }
+
+ // Other getters
+
+ RemotePtr<void> start() const { return remote(start_addr_); }
+ RemotePtr<void> end() const { return remote((char*)start_addr_ + size_); }
+ RemotePtr<void> permanent_address() const { return remote(permanent_addr_); }
+ std::size_t size() const { return size_; }
+ StorageType storage_type() const { return storage_type_; }
+ RegionType region_type() const { return region_type_; }
+
+ bool contain(RemotePtr<void> p) const
+ {
+ return p >= start() && p < end();
+ }
+};
+
+RegionSnapshot privatized_region(
+ RegionType region_type, void *start_addr, void* permanent_addr,
+ std::size_t size);
+RegionSnapshot dense_region(
+ RegionType type, void *start_addr, void* data_addr, std::size_t size);
+simgrid::mc::RegionSnapshot sparse_region(
+ RegionType type, void *start_addr, void* data_addr, std::size_t size);
+simgrid::mc::RegionSnapshot region(
+ RegionType type, void *start_addr, void* data_addr, std::size_t size);
+
+}
+}
+
+typedef simgrid::mc::RegionSnapshot s_mc_mem_region_t;
+typedef s_mc_mem_region_t* mc_mem_region_t;
+#endif
--- /dev/null
+/* Copyright (c) 2008-2018. The SimGrid Team. All rights reserved. */
+
+/* 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. */
+
+/** \file compare.cpp Memory snapshooting and comparison */
+
+#include <cinttypes>
+
+#include <array>
+#include <memory>
+#include <set>
+#include <utility>
+#include <unordered_set>
+
+#include "xbt/dynar.h"
+#include "xbt/sysdep.h"
+#include <xbt/mmalloc.h>
+
+#include <mc/mc.h>
+#include <mc/datatypes.h>
+
+#include "src/internal_config.h"
+
+#include "src/xbt/mmalloc/mmprivate.h"
+
+#if HAVE_SMPI
+#include "src/smpi/include/private.hpp"
+#endif
+
+#include "src/mc/Frame.hpp"
+#include "src/mc/ObjectInformation.hpp"
+#include "src/mc/Type.hpp"
+#include "src/mc/Variable.hpp"
+#include "src/mc/mc_config.hpp"
+#include "src/mc/mc_dwarf.hpp"
+#include "src/mc/mc_forward.hpp"
+#include "src/mc/mc_private.hpp"
+#include "src/mc/mc_smx.hpp"
+#include "src/mc/mc_snapshot.hpp"
+
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_compare, xbt, "Logging specific to mc_compare in mc");
+
+namespace simgrid {
+namespace mc {
+
+struct HeapLocation;
+typedef std::array<HeapLocation, 2> HeapLocationPair;
+typedef std::set<HeapLocationPair> HeapLocationPairs;
+struct HeapArea;
+struct ProcessComparisonState;
+struct StateComparator;
+
+static int compare_heap_area(
+ StateComparator& state,
+ int process_index, const void *area1, const void* area2,
+ Snapshot* snapshot1, Snapshot* snapshot2,
+ HeapLocationPairs* previous, Type* type, int pointer_level);
+
+}
+}
+
+using simgrid::mc::remote;
+
+/*********************************** Heap comparison ***********************************/
+/***************************************************************************************/
+
+namespace simgrid {
+namespace mc {
+
+class HeapLocation {
+public:
+ int block_ = 0;
+ int fragment_ = 0;
+
+ HeapLocation() = default;
+ HeapLocation(int block, int fragment = 0) : block_(block), fragment_(fragment) {}
+
+ bool operator==(HeapLocation const& that) const
+ {
+ return block_ == that.block_ && fragment_ == that.fragment_;
+ }
+ bool operator<(HeapLocation const& that) const
+ {
+ return std::make_pair(block_, fragment_) < std::make_pair(that.block_, that.fragment_);
+ }
+};
+
+static inline
+HeapLocationPair makeHeapLocationPair(int block1, int fragment1, int block2, int fragment2)
+{
+ return simgrid::mc::HeapLocationPair{{
+ simgrid::mc::HeapLocation(block1, fragment1),
+ simgrid::mc::HeapLocation(block2, fragment2)
+ }};
+}
+
+class HeapArea : public HeapLocation {
+public:
+ bool valid_ = false;
+ HeapArea() = default;
+ explicit HeapArea(int block) : valid_(true) { block_ = block; }
+ HeapArea(int block, int fragment) : valid_(true)
+ {
+ block_ = block;
+ fragment_ = fragment;
+ }
+};
+
+class ProcessComparisonState {
+public:
+ std::vector<simgrid::mc::IgnoredHeapRegion>* to_ignore = nullptr;
+ std::vector<HeapArea> equals_to;
+ std::vector<simgrid::mc::Type*> types;
+ std::size_t heapsize = 0;
+
+ void initHeapInformation(xbt_mheap_t heap, std::vector<simgrid::mc::IgnoredHeapRegion>* i);
+};
+
+namespace {
+
+/** A hash which works with more stuff
+ *
+ * It can hash pairs: the standard hash currently doesn't include this.
+ */
+template <class X> class hash : public std::hash<X> {
+};
+
+template <class X, class Y> class hash<std::pair<X, Y>> {
+public:
+ std::size_t operator()(std::pair<X,Y>const& x) const
+ {
+ hash<X> h1;
+ hash<X> h2;
+ return h1(x.first) ^ h2(x.second);
+ }
+};
+
+}
+
+class StateComparator {
+public:
+ s_xbt_mheap_t std_heap_copy;
+ std::size_t heaplimit;
+ std::array<ProcessComparisonState, 2> processStates;
+
+ std::unordered_set<std::pair<void*, void*>, hash<std::pair<void*, void*>>> compared_pointers;
+
+ void clear()
+ {
+ compared_pointers.clear();
+ }
+
+ int initHeapInformation(
+ xbt_mheap_t heap1, xbt_mheap_t heap2,
+ std::vector<simgrid::mc::IgnoredHeapRegion>* i1,
+ std::vector<simgrid::mc::IgnoredHeapRegion>* i2);
+
+ HeapArea& equals_to1_(std::size_t i, std::size_t j)
+ {
+ return processStates[0].equals_to[ MAX_FRAGMENT_PER_BLOCK * i + j];
+ }
+ HeapArea& equals_to2_(std::size_t i, std::size_t j)
+ {
+ return processStates[1].equals_to[ MAX_FRAGMENT_PER_BLOCK * i + j];
+ }
+ Type*& types1_(std::size_t i, std::size_t j)
+ {
+ return processStates[0].types[ MAX_FRAGMENT_PER_BLOCK * i + j];
+ }
+ Type*& types2_(std::size_t i, std::size_t j)
+ {
+ return processStates[1].types[ MAX_FRAGMENT_PER_BLOCK * i + j];
+ }
+
+ HeapArea const& equals_to1_(std::size_t i, std::size_t j) const
+ {
+ return processStates[0].equals_to[ MAX_FRAGMENT_PER_BLOCK * i + j];
+ }
+ HeapArea const& equals_to2_(std::size_t i, std::size_t j) const
+ {
+ return processStates[1].equals_to[ MAX_FRAGMENT_PER_BLOCK * i + j];
+ }
+ Type* const& types1_(std::size_t i, std::size_t j) const
+ {
+ return processStates[0].types[ MAX_FRAGMENT_PER_BLOCK * i + j];
+ }
+ Type* const& types2_(std::size_t i, std::size_t j) const
+ {
+ return processStates[1].types[ MAX_FRAGMENT_PER_BLOCK * i + j];
+ }
+
+ /** Check whether two blocks are known to be matching
+ *
+ * @param b1 Block of state 1
+ * @param b2 Block of state 2
+ * @return if the blocks are known to be matching
+ */
+ bool blocksEqual(int b1, int b2) const
+ {
+ return this->equals_to1_(b1, 0).block_ == b2 && this->equals_to2_(b2, 0).block_ == b1;
+ }
+
+ /** Check whether two fragments are known to be matching
+ *
+ * @param b1 Block of state 1
+ * @param f1 Fragment of state 1
+ * @param b2 Block of state 2
+ * @param f2 Fragment of state 2
+ * @return if the fragments are known to be matching
+ */
+ int fragmentsEqual(int b1, int f1, int b2, int f2) const
+ {
+ return this->equals_to1_(b1, f1).block_ == b2 && this->equals_to1_(b1, f1).fragment_ == f2 &&
+ this->equals_to2_(b2, f2).block_ == b1 && this->equals_to2_(b2, f2).fragment_ == f1;
+ }
+
+ void match_equals(HeapLocationPairs* list);
+};
+
+}
+}
+
+/************************************************************************************/
+
+static ssize_t heap_comparison_ignore_size(
+ std::vector<simgrid::mc::IgnoredHeapRegion>* ignore_list,
+ const void *address)
+{
+ int start = 0;
+ int end = ignore_list->size() - 1;
+
+ while (start <= end) {
+ unsigned int cursor = (start + end) / 2;
+ simgrid::mc::IgnoredHeapRegion const& region = (*ignore_list)[cursor];
+ if (region.address == address)
+ return region.size;
+ if (region.address < address)
+ start = cursor + 1;
+ if (region.address > address)
+ end = cursor - 1;
+ }
+
+ return -1;
+}
+
+static bool is_stack(const void *address)
+{
+ for (auto const& stack : mc_model_checker->process().stack_areas())
+ if (address == stack.address)
+ return true;
+ return false;
+}
+
+// TODO, this should depend on the snapshot?
+static bool is_block_stack(int block)
+{
+ for (auto const& stack : mc_model_checker->process().stack_areas())
+ if (block == stack.block)
+ return true;
+ return false;
+}
+
+namespace simgrid {
+namespace mc {
+
+void StateComparator::match_equals(HeapLocationPairs* list)
+{
+ for (auto const& pair : *list) {
+ if (pair[0].fragment_ != -1) {
+ this->equals_to1_(pair[0].block_, pair[0].fragment_) = simgrid::mc::HeapArea(pair[1].block_, pair[1].fragment_);
+ this->equals_to2_(pair[1].block_, pair[1].fragment_) = simgrid::mc::HeapArea(pair[0].block_, pair[0].fragment_);
+ } else {
+ this->equals_to1_(pair[0].block_, 0) = simgrid::mc::HeapArea(pair[1].block_, pair[1].fragment_);
+ this->equals_to2_(pair[1].block_, 0) = simgrid::mc::HeapArea(pair[0].block_, pair[0].fragment_);
+ }
+ }
+}
+
+void ProcessComparisonState::initHeapInformation(xbt_mheap_t heap,
+ std::vector<simgrid::mc::IgnoredHeapRegion>* i)
+{
+ auto heaplimit = heap->heaplimit;
+ this->heapsize = heap->heapsize;
+ this->to_ignore = i;
+ this->equals_to.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, HeapArea());
+ this->types.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, nullptr);
+}
+
+int StateComparator::initHeapInformation(xbt_mheap_t heap1, xbt_mheap_t heap2,
+ std::vector<simgrid::mc::IgnoredHeapRegion>* i1,
+ std::vector<simgrid::mc::IgnoredHeapRegion>* i2)
+{
+ if ((heap1->heaplimit != heap2->heaplimit) || (heap1->heapsize != heap2->heapsize))
+ return -1;
+ this->heaplimit = heap1->heaplimit;
+ this->std_heap_copy = *mc_model_checker->process().get_heap();
+ this->processStates[0].initHeapInformation(heap1, i1);
+ this->processStates[1].initHeapInformation(heap2, i2);
+ return 0;
+}
+
+// TODO, have a robust way to find it in O(1)
+static inline
+mc_mem_region_t MC_get_heap_region(simgrid::mc::Snapshot* snapshot)
+{
+ for (auto const& region : snapshot->snapshot_regions)
+ if (region->region_type() == simgrid::mc::RegionType::Heap)
+ return region.get();
+ xbt_die("No heap region");
+}
+
+static
+int mmalloc_compare_heap(
+ simgrid::mc::StateComparator& state, simgrid::mc::Snapshot* snapshot1, simgrid::mc::Snapshot* snapshot2)
+{
+ simgrid::mc::RemoteClient* process = &mc_model_checker->process();
+
+ /* Start comparison */
+ size_t i1;
+ size_t i2;
+ size_t j1;
+ size_t j2;
+ size_t k;
+ void* addr_block1;
+ void* addr_block2;
+ void* addr_frag1;
+ void* addr_frag2;
+ int nb_diff1 = 0;
+ int nb_diff2 = 0;
+ int equal;
+
+ /* Check busy blocks */
+ i1 = 1;
+
+ malloc_info heapinfo_temp1;
+ malloc_info heapinfo_temp2;
+ malloc_info heapinfo_temp2b;
+
+ mc_mem_region_t heap_region1 = MC_get_heap_region(snapshot1);
+ mc_mem_region_t heap_region2 = MC_get_heap_region(snapshot2);
+
+ // This is the address of std_heap->heapinfo in the application process:
+ void* heapinfo_address = &((xbt_mheap_t) process->heap_address)->heapinfo;
+
+ // This is in snapshot do not use them directly:
+ const malloc_info* heapinfos1 = snapshot1->read<malloc_info*>(
+ RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address), simgrid::mc::ProcessIndexMissing);
+ const malloc_info* heapinfos2 = snapshot2->read<malloc_info*>(
+ RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address), simgrid::mc::ProcessIndexMissing);
+
+ while (i1 < state.heaplimit) {
+
+ const malloc_info* heapinfo1 = (const malloc_info*) MC_region_read(heap_region1, &heapinfo_temp1, &heapinfos1[i1], sizeof(malloc_info));
+ const malloc_info* heapinfo2 = (const malloc_info*) MC_region_read(heap_region2, &heapinfo_temp2, &heapinfos2[i1], sizeof(malloc_info));
+
+ if (heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type == MMALLOC_TYPE_HEAPINFO) { /* Free block */
+ i1 ++;
+ continue;
+ }
+
+ if (heapinfo1->type < 0) {
+ fprintf(stderr, "Unkown mmalloc block type.\n");
+ abort();
+ }
+
+ addr_block1 = ((void*)(((ADDR2UINT(i1)) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase));
+
+ if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED) { /* Large block */
+
+ if (is_stack(addr_block1)) {
+ for (k = 0; k < heapinfo1->busy_block.size; k++)
+ state.equals_to1_(i1 + k, 0) = HeapArea(i1, -1);
+ for (k = 0; k < heapinfo2->busy_block.size; k++)
+ state.equals_to2_(i1 + k, 0) = HeapArea(i1, -1);
+ i1 += heapinfo1->busy_block.size;
+ continue;
+ }
+
+ if (state.equals_to1_(i1, 0).valid_) {
+ i1++;
+ continue;
+ }
+
+ i2 = 1;
+ equal = 0;
+
+ /* Try first to associate to same block in the other heap */
+ if (heapinfo2->type == heapinfo1->type && state.equals_to2_(i1, 0).valid_ == 0) {
+ addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
+ int res_compare = compare_heap_area(state, simgrid::mc::ProcessIndexMissing, addr_block1, addr_block2,
+ snapshot1, snapshot2, nullptr, nullptr, 0);
+ if (res_compare != 1) {
+ for (k = 1; k < heapinfo2->busy_block.size; k++)
+ state.equals_to2_(i1 + k, 0) = HeapArea(i1, -1);
+ for (k = 1; k < heapinfo1->busy_block.size; k++)
+ state.equals_to1_(i1 + k, 0) = HeapArea(i1, -1);
+ equal = 1;
+ i1 += heapinfo1->busy_block.size;
+ }
+ }
+
+ while (i2 < state.heaplimit && not equal) {
+
+ addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
+
+ if (i2 == i1) {
+ i2++;
+ continue;
+ }
+
+ const malloc_info* heapinfo2b = (const malloc_info*) MC_region_read(heap_region2, &heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info));
+
+ if (heapinfo2b->type != MMALLOC_TYPE_UNFRAGMENTED) {
+ i2++;
+ continue;
+ }
+
+ if (state.equals_to2_(i2, 0).valid_) {
+ i2++;
+ continue;
+ }
+
+ int res_compare = compare_heap_area(state, simgrid::mc::ProcessIndexMissing, addr_block1, addr_block2,
+ snapshot1, snapshot2, nullptr, nullptr, 0);
+
+ if (res_compare != 1) {
+ for (k = 1; k < heapinfo2b->busy_block.size; k++)
+ state.equals_to2_(i2 + k, 0) = HeapArea(i1, -1);
+ for (k = 1; k < heapinfo1->busy_block.size; k++)
+ state.equals_to1_(i1 + k, 0) = HeapArea(i2, -1);
+ equal = 1;
+ i1 += heapinfo1->busy_block.size;
+ }
+
+ i2++;
+ }
+
+ if (not equal) {
+ XBT_DEBUG("Block %zu not found (size_used = %zu, addr = %p)", i1, heapinfo1->busy_block.busy_size, addr_block1);
+ i1 = state.heaplimit + 1;
+ nb_diff1++;
+ }
+
+ } else { /* Fragmented block */
+
+ for (j1 = 0; j1 < (size_t) (BLOCKSIZE >> heapinfo1->type); j1++) {
+
+ if (heapinfo1->busy_frag.frag_size[j1] == -1) /* Free fragment_ */
+ continue;
+
+ if (state.equals_to1_(i1, j1).valid_)
+ continue;
+
+ addr_frag1 = (void*)((char*)addr_block1 + (j1 << heapinfo1->type));
+
+ i2 = 1;
+ equal = 0;
+
+ /* Try first to associate to same fragment_ in the other heap */
+ if (heapinfo2->type == heapinfo1->type && not state.equals_to2_(i1, j1).valid_) {
+ addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE +
+ (char *) state.std_heap_copy.heapbase;
+ addr_frag2 =
+ (void *) ((char *) addr_block2 +
+ (j1 << heapinfo2->type));
+ int res_compare = compare_heap_area(state, simgrid::mc::ProcessIndexMissing, addr_frag1, addr_frag2,
+ snapshot1, snapshot2, nullptr, nullptr, 0);
+ if (res_compare != 1)
+ equal = 1;
+ }
+
+ while (i2 < state.heaplimit && not equal) {
+
+ const malloc_info* heapinfo2b = (const malloc_info*) MC_region_read(
+ heap_region2, &heapinfo_temp2b, &heapinfos2[i2],
+ sizeof(malloc_info));
+
+ if (heapinfo2b->type == MMALLOC_TYPE_FREE || heapinfo2b->type == MMALLOC_TYPE_HEAPINFO) {
+ i2 ++;
+ continue;
+ }
+
+ // We currently do not match fragments with unfragmented blocks (maybe we should).
+ if (heapinfo2b->type == MMALLOC_TYPE_UNFRAGMENTED) {
+ i2++;
+ continue;
+ }
+
+ if (heapinfo2b->type < 0) {
+ fprintf(stderr, "Unknown mmalloc block type.\n");
+ abort();
+ }
+
+ for (j2 = 0; j2 < (size_t) (BLOCKSIZE >> heapinfo2b->type);
+ j2++) {
+
+ if (i2 == i1 && j2 == j1)
+ continue;
+
+ if (state.equals_to2_(i2, j2).valid_)
+ continue;
+
+ addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
+ addr_frag2 = (void*)((char*)addr_block2 + (j2 << heapinfo2b->type));
+
+ int res_compare = compare_heap_area(state, simgrid::mc::ProcessIndexMissing, addr_frag1, addr_frag2,
+ snapshot2, snapshot2, nullptr, nullptr, 0);
+ if (res_compare != 1) {
+ equal = 1;
+ break;
+ }
+ }
+
+ i2++;
+ }
+
+ if (not equal) {
+ XBT_DEBUG("Block %zu, fragment_ %zu not found (size_used = %zd, address = %p)\n", i1, j1,
+ heapinfo1->busy_frag.frag_size[j1], addr_frag1);
+ i1 = state.heaplimit + 1;
+ nb_diff1++;
+ break;
+ }
+ }
+
+ i1++;
+ }
+ }
+
+ /* All blocks/fragments are equal to another block/fragment_ ? */
+ size_t i = 1;
+ size_t j = 0;
+
+ for(i = 1; i < state.heaplimit; i++) {
+ const malloc_info* heapinfo1 = (const malloc_info*) MC_region_read(
+ heap_region1, &heapinfo_temp1, &heapinfos1[i], sizeof(malloc_info));
+
+ if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo1->busy_block.busy_size > 0 &&
+ not state.equals_to1_(i, 0).valid_) {
+ XBT_DEBUG("Block %zu not found (size used = %zu)", i, heapinfo1->busy_block.busy_size);
+ nb_diff1++;
+ }
+
+ if (heapinfo1->type <= 0)
+ continue;
+ for (j = 0; j < (size_t) (BLOCKSIZE >> heapinfo1->type); j++)
+ if (i1 == state.heaplimit && heapinfo1->busy_frag.frag_size[j] > 0 && not state.equals_to1_(i, j).valid_) {
+ XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)", i, j, heapinfo1->busy_frag.frag_size[j]);
+ nb_diff1++;
+ }
+ }
+
+ if (i1 == state.heaplimit)
+ XBT_DEBUG("Number of blocks/fragments not found in heap1: %d", nb_diff1);
+
+ for (i=1; i < state.heaplimit; i++) {
+ const malloc_info* heapinfo2 = (const malloc_info*) MC_region_read(
+ heap_region2, &heapinfo_temp2, &heapinfos2[i], sizeof(malloc_info));
+ if (heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo2->busy_block.busy_size > 0 &&
+ not state.equals_to2_(i, 0).valid_) {
+ XBT_DEBUG("Block %zu not found (size used = %zu)", i,
+ heapinfo2->busy_block.busy_size);
+ nb_diff2++;
+ }
+
+ if (heapinfo2->type <= 0)
+ continue;
+
+ for (j = 0; j < (size_t) (BLOCKSIZE >> heapinfo2->type); j++)
+ if (i1 == state.heaplimit && heapinfo2->busy_frag.frag_size[j] > 0 && not state.equals_to2_(i, j).valid_) {
+ XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)",
+ i, j, heapinfo2->busy_frag.frag_size[j]);
+ nb_diff2++;
+ }
+
+ }
+
+ if (i1 == state.heaplimit)
+ XBT_DEBUG("Number of blocks/fragments not found in heap2: %d", nb_diff2);
+
+ return nb_diff1 > 0 || nb_diff2 > 0;
+}
+
+/**
+ *
+ * @param state
+ * @param real_area1 Process address for state 1
+ * @param real_area2 Process address for state 2
+ * @param snapshot1 Snapshot of state 1
+ * @param snapshot2 Snapshot of state 2
+ * @param previous
+ * @param size
+ * @param check_ignore
+ */
+static int compare_heap_area_without_type(
+ simgrid::mc::StateComparator& state, int process_index,
+ const void *real_area1, const void *real_area2,
+ simgrid::mc::Snapshot* snapshot1,
+ simgrid::mc::Snapshot* snapshot2,
+ HeapLocationPairs* previous, int size,
+ int check_ignore)
+{
+ simgrid::mc::RemoteClient* process = &mc_model_checker->process();
+ mc_mem_region_t heap_region1 = MC_get_heap_region(snapshot1);
+ mc_mem_region_t heap_region2 = MC_get_heap_region(snapshot2);
+
+ for (int i = 0; i < size; ) {
+
+ if (check_ignore > 0) {
+ ssize_t ignore1 = heap_comparison_ignore_size(
+ state.processStates[0].to_ignore, (char *) real_area1 + i);
+ if (ignore1 != -1) {
+ ssize_t ignore2 = heap_comparison_ignore_size(
+ state.processStates[1].to_ignore, (char *) real_area2 + i);
+ if (ignore2 == ignore1) {
+ if (ignore1 == 0) {
+ check_ignore--;
+ return 0;
+ } else {
+ i = i + ignore2;
+ check_ignore--;
+ continue;
+ }
+ }
+ }
+ }
+
+ if (MC_snapshot_region_memcmp(((char *) real_area1) + i, heap_region1, ((char *) real_area2) + i, heap_region2, 1) != 0) {
+
+ int pointer_align = (i / sizeof(void *)) * sizeof(void *);
+ const void* addr_pointed1 = snapshot1->read(
+ remote((void**)((char *) real_area1 + pointer_align)), process_index);
+ const void* addr_pointed2 = snapshot2->read(
+ remote((void**)((char *) real_area2 + pointer_align)), process_index);
+
+ if (process->in_maestro_stack(remote(addr_pointed1))
+ && process->in_maestro_stack(remote(addr_pointed2))) {
+ i = pointer_align + sizeof(void *);
+ continue;
+ }
+
+ if (addr_pointed1 > state.std_heap_copy.heapbase
+ && addr_pointed1 < mc_snapshot_get_heap_end(snapshot1)
+ && addr_pointed2 > state.std_heap_copy.heapbase
+ && addr_pointed2 < mc_snapshot_get_heap_end(snapshot2)) {
+ // Both addreses are in the heap:
+ int res_compare = compare_heap_area(state ,process_index,
+ addr_pointed1, addr_pointed2,
+ snapshot1, snapshot2, previous, nullptr, 0);
+ if (res_compare == 1)
+ return res_compare;
+ i = pointer_align + sizeof(void *);
+ continue;
+ }
+
+ return 1;
+ }
+
+ i++;
+ }
+
+ return 0;
+}
+
+/**
+ *
+ * @param state
+ * @param real_area1 Process address for state 1
+ * @param real_area2 Process address for state 2
+ * @param snapshot1 Snapshot of state 1
+ * @param snapshot2 Snapshot of state 2
+ * @param previous
+ * @param type
+ * @param area_size either a byte_size or an elements_count (?)
+ * @param check_ignore
+ * @param pointer_level
+ * @return 0 (same), 1 (different), -1 (unknown)
+ */
+static int compare_heap_area_with_type(
+ simgrid::mc::StateComparator& state, int process_index,
+ const void *real_area1, const void *real_area2,
+ simgrid::mc::Snapshot* snapshot1,
+ simgrid::mc::Snapshot* snapshot2,
+ HeapLocationPairs* previous, simgrid::mc::Type* type,
+ int area_size, int check_ignore,
+ int pointer_level)
+{
+ do {
+
+ // HACK: This should not happen but in pratice, there are some
+ // DW_TAG_typedef without an associated DW_AT_type:
+ //<1><538832>: Abbrev Number: 111 (DW_TAG_typedef)
+ // <538833> DW_AT_name : (indirect string, offset: 0x2292f3): gregset_t
+ // <538837> DW_AT_decl_file : 98
+ // <538838> DW_AT_decl_line : 37
+ if (type == nullptr)
+ return 0;
+
+ if (is_stack(real_area1) && is_stack(real_area2))
+ return 0;
+
+ if (check_ignore > 0) {
+ ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, real_area1);
+ if (ignore1 > 0 && heap_comparison_ignore_size(state.processStates[1].to_ignore, real_area2) == ignore1)
+ return 0;
+ }
+
+ simgrid::mc::Type* subtype;
+ simgrid::mc::Type* subsubtype;
+ int res;
+ int elm_size;
+ const void* addr_pointed1;
+ const void* addr_pointed2;
+
+ mc_mem_region_t heap_region1 = MC_get_heap_region(snapshot1);
+ mc_mem_region_t heap_region2 = MC_get_heap_region(snapshot2);
+
+ switch (type->type) {
+ case DW_TAG_unspecified_type:
+ return 1;
+
+ case DW_TAG_base_type:
+ if (not type->name.empty() && type->name == "char") { /* String, hence random (arbitrary ?) size */
+ if (real_area1 == real_area2)
+ return -1;
+ else
+ return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, area_size) != 0;
+ } else {
+ if (area_size != -1 && type->byte_size != area_size)
+ return -1;
+ else
+ return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
+ }
+ break;
+
+ case DW_TAG_enumeration_type:
+ if (area_size != -1 && type->byte_size != area_size)
+ return -1;
+ return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
+
+ case DW_TAG_typedef:
+ case DW_TAG_const_type:
+ case DW_TAG_volatile_type:
+ // Poor man's TCO:
+ type = type->subtype;
+ continue; // restart
+
+ case DW_TAG_array_type:
+ subtype = type->subtype;
+ switch (subtype->type) {
+ case DW_TAG_unspecified_type:
+ return 1;
+
+ case DW_TAG_base_type:
+ case DW_TAG_enumeration_type:
+ case DW_TAG_pointer_type:
+ case DW_TAG_reference_type:
+ case DW_TAG_rvalue_reference_type:
+ case DW_TAG_structure_type:
+ case DW_TAG_class_type:
+ case DW_TAG_union_type:
+ if (subtype->full_type)
+ subtype = subtype->full_type;
+ elm_size = subtype->byte_size;
+ break;
+ // TODO, just remove the type indirection?
+ case DW_TAG_const_type:
+ case DW_TAG_typedef:
+ case DW_TAG_volatile_type:
+ subsubtype = subtype->subtype;
+ if (subsubtype->full_type)
+ subsubtype = subsubtype->full_type;
+ elm_size = subsubtype->byte_size;
+ break;
+ default:
+ return 0;
+ break;
+ }
+ for (int i = 0; i < type->element_count; i++) {
+ // TODO, add support for variable stride (DW_AT_byte_stride)
+ res = compare_heap_area_with_type(state, process_index, (char*)real_area1 + (i * elm_size),
+ (char*)real_area2 + (i * elm_size), snapshot1, snapshot2, previous,
+ type->subtype, subtype->byte_size, check_ignore, pointer_level);
+ if (res == 1)
+ return res;
+ }
+ return 0;
+
+ case DW_TAG_reference_type:
+ case DW_TAG_rvalue_reference_type:
+ case DW_TAG_pointer_type:
+ if (type->subtype && type->subtype->type == DW_TAG_subroutine_type) {
+ addr_pointed1 = snapshot1->read(remote((void**)real_area1), process_index);
+ addr_pointed2 = snapshot2->read(remote((void**)real_area2), process_index);
+ return (addr_pointed1 != addr_pointed2);
+ }
+ pointer_level++;
+ if (pointer_level <= 1) {
+ addr_pointed1 = snapshot1->read(remote((void**)real_area1), process_index);
+ addr_pointed2 = snapshot2->read(remote((void**)real_area2), process_index);
+ if (addr_pointed1 > state.std_heap_copy.heapbase && addr_pointed1 < mc_snapshot_get_heap_end(snapshot1) &&
+ addr_pointed2 > state.std_heap_copy.heapbase && addr_pointed2 < mc_snapshot_get_heap_end(snapshot2))
+ return compare_heap_area(state, process_index, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous,
+ type->subtype, pointer_level);
+ else
+ return (addr_pointed1 != addr_pointed2);
+ }
+ for (size_t i = 0; i < (area_size / sizeof(void*)); i++) {
+ addr_pointed1 = snapshot1->read(remote((void**)((char*)real_area1 + i * sizeof(void*))), process_index);
+ addr_pointed2 = snapshot2->read(remote((void**)((char*)real_area2 + i * sizeof(void*))), process_index);
+ if (addr_pointed1 > state.std_heap_copy.heapbase && addr_pointed1 < mc_snapshot_get_heap_end(snapshot1) &&
+ addr_pointed2 > state.std_heap_copy.heapbase && addr_pointed2 < mc_snapshot_get_heap_end(snapshot2))
+ res = compare_heap_area(state, process_index, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous,
+ type->subtype, pointer_level);
+ else
+ res = (addr_pointed1 != addr_pointed2);
+ if (res == 1)
+ return res;
+ }
+ return 0;
+
+ case DW_TAG_structure_type:
+ case DW_TAG_class_type:
+ if (type->full_type)
+ type = type->full_type;
+ if (area_size != -1 && type->byte_size != area_size) {
+ if (area_size <= type->byte_size || area_size % type->byte_size != 0)
+ return -1;
+ for (size_t i = 0; i < (size_t)(area_size / type->byte_size); i++) {
+ int res = compare_heap_area_with_type(state, process_index, (char*)real_area1 + i * type->byte_size,
+ (char*)real_area2 + i * type->byte_size, snapshot1, snapshot2,
+ previous, type, -1, check_ignore, 0);
+ if (res == 1)
+ return res;
+ }
+ } else {
+ for (simgrid::mc::Member& member : type->members) {
+ // TODO, optimize this? (for the offset case)
+ void* real_member1 = simgrid::dwarf::resolve_member(real_area1, type, &member,
+ (simgrid::mc::AddressSpace*)snapshot1, process_index);
+ void* real_member2 = simgrid::dwarf::resolve_member(real_area2, type, &member,
+ (simgrid::mc::AddressSpace*)snapshot2, process_index);
+ int res = compare_heap_area_with_type(state, process_index, real_member1, real_member2, snapshot1,
+ snapshot2, previous, member.type, -1, check_ignore, 0);
+ if (res == 1)
+ return res;
+ }
+ }
+ return 0;
+
+ case DW_TAG_union_type:
+ return compare_heap_area_without_type(state, process_index, real_area1, real_area2, snapshot1, snapshot2,
+ previous, type->byte_size, check_ignore);
+
+ default:
+ return 0;
+ }
+
+ xbt_die("Unreachable");
+ } while (true);
+}
+
+/** Infer the type of a part of the block from the type of the block
+ *
+ * TODO, handle DW_TAG_array_type as well as arrays of the object ((*p)[5], p[5])
+ *
+ * TODO, handle subfields ((*p).bar.foo, (*p)[5].bar…)
+ *
+ * @param type DWARF type ID of the root address
+ * @param area_size
+ * @return DWARF type ID for given offset
+ */
+static simgrid::mc::Type* get_offset_type(void *real_base_address, simgrid::mc::Type* type,
+ int offset, int area_size,
+ simgrid::mc::Snapshot* snapshot, int process_index)
+{
+
+ // Beginning of the block, the infered variable type if the type of the block:
+ if (offset == 0)
+ return type;
+
+ switch (type->type) {
+
+ case DW_TAG_structure_type:
+ case DW_TAG_class_type:
+ if (type->full_type)
+ type = type->full_type;
+ if (area_size != -1 && type->byte_size != area_size) {
+ if (area_size > type->byte_size && area_size % type->byte_size == 0)
+ return type;
+ else
+ return nullptr;
+ }
+
+ for (simgrid::mc::Member& member : type->members) {
+ if (member.has_offset_location()) {
+ // We have the offset, use it directly (shortcut):
+ if (member.offset() == offset)
+ return member.type;
+ } else {
+ void* real_member = simgrid::dwarf::resolve_member(real_base_address, type, &member, snapshot, process_index);
+ if ((char*)real_member - (char*)real_base_address == offset)
+ return member.type;
+ }
+ }
+ return nullptr;
+
+ default:
+ /* FIXME: other cases ? */
+ return nullptr;
+
+ }
+}
+
+/**
+ *
+ * @param area1 Process address for state 1
+ * @param area2 Process address for state 2
+ * @param snapshot1 Snapshot of state 1
+ * @param snapshot2 Snapshot of state 2
+ * @param previous Pairs of blocks already compared on the current path (or nullptr)
+ * @param type_id Type of variable
+ * @param pointer_level
+ * @return 0 (same), 1 (different), -1
+ */
+static
+int compare_heap_area(simgrid::mc::StateComparator& state, int process_index,
+ const void *area1, const void *area2,
+ simgrid::mc::Snapshot* snapshot1,
+ simgrid::mc::Snapshot* snapshot2,
+ HeapLocationPairs* previous,
+ simgrid::mc::Type* type, int pointer_level)
+{
+ simgrid::mc::RemoteClient* process = &mc_model_checker->process();
+
+ ssize_t block1;
+ ssize_t block2;
+ ssize_t size;
+ int check_ignore = 0;
+
+ int type_size = -1;
+ int offset1 = 0;
+ int offset2 = 0;
+ int new_size1 = -1;
+ int new_size2 = -1;
+
+ simgrid::mc::Type* new_type1 = nullptr;
+ simgrid::mc::Type* new_type2 = nullptr;
+
+ bool match_pairs = false;
+
+ // This is the address of std_heap->heapinfo in the application process:
+ void* heapinfo_address = &((xbt_mheap_t) process->heap_address)->heapinfo;
+
+ const malloc_info* heapinfos1 = snapshot1->read(remote((const malloc_info**)heapinfo_address), process_index);
+ const malloc_info* heapinfos2 = snapshot2->read(remote((const malloc_info**)heapinfo_address), process_index);
+
+ malloc_info heapinfo_temp1;
+ malloc_info heapinfo_temp2;
+
+ simgrid::mc::HeapLocationPairs current;
+ if (previous == nullptr) {
+ previous = ¤t;
+ match_pairs = true;
+ }
+
+ // Get block number:
+ block1 = ((char*)area1 - (char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
+ block2 = ((char*)area2 - (char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
+
+ // If either block is a stack block:
+ if (is_block_stack((int) block1) && is_block_stack((int) block2)) {
+ previous->insert(simgrid::mc::makeHeapLocationPair(block1, -1, block2, -1));
+ if (match_pairs)
+ state.match_equals(previous);
+ return 0;
+ }
+
+ // If either block is not in the expected area of memory:
+ if (((char*)area1 < (char*)state.std_heap_copy.heapbase) || (block1 > (ssize_t)state.processStates[0].heapsize) ||
+ (block1 < 1) || ((char*)area2 < (char*)state.std_heap_copy.heapbase) ||
+ (block2 > (ssize_t)state.processStates[1].heapsize) || (block2 < 1)) {
+ return 1;
+ }
+
+ // Process address of the block:
+ void* real_addr_block1 = (ADDR2UINT(block1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
+ void* real_addr_block2 = (ADDR2UINT(block2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
+
+ if (type) {
+ if (type->full_type)
+ type = type->full_type;
+
+ // This assume that for "boring" types (volatile ...) byte_size is absent:
+ while (type->byte_size == 0 && type->subtype != nullptr)
+ type = type->subtype;
+
+ // Find type_size:
+ if (type->type == DW_TAG_pointer_type ||
+ (type->type == DW_TAG_base_type && not type->name.empty() && type->name == "char"))
+ type_size = -1;
+ else
+ type_size = type->byte_size;
+
+ }
+
+ mc_mem_region_t heap_region1 = MC_get_heap_region(snapshot1);
+ mc_mem_region_t heap_region2 = MC_get_heap_region(snapshot2);
+
+ const malloc_info* heapinfo1 = (const malloc_info*) MC_region_read(
+ heap_region1, &heapinfo_temp1, &heapinfos1[block1], sizeof(malloc_info));
+ const malloc_info* heapinfo2 = (const malloc_info*) MC_region_read(
+ heap_region2, &heapinfo_temp2, &heapinfos2[block2], sizeof(malloc_info));
+
+ if ((heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type==MMALLOC_TYPE_HEAPINFO)
+ && (heapinfo2->type == MMALLOC_TYPE_FREE || heapinfo2->type ==MMALLOC_TYPE_HEAPINFO)) {
+ /* Free block */
+ if (match_pairs)
+ state.match_equals(previous);
+ return 0;
+ }
+
+ if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED) {
+ /* Complete block */
+
+ // TODO, lookup variable type from block type as done for fragmented blocks
+
+ if (state.equals_to1_(block1, 0).valid_ && state.equals_to2_(block2, 0).valid_ &&
+ state.blocksEqual(block1, block2)) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return 0;
+ }
+
+ if (type_size != -1 && type_size != (ssize_t)heapinfo1->busy_block.busy_size &&
+ type_size != (ssize_t)heapinfo2->busy_block.busy_size &&
+ (type->name.empty() || type->name == "struct s_smx_context")) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return -1;
+ }
+
+ if (heapinfo1->busy_block.size != heapinfo2->busy_block.size)
+ return 1;
+ if (heapinfo1->busy_block.busy_size != heapinfo2->busy_block.busy_size)
+ return 1;
+
+ if (not previous->insert(simgrid::mc::makeHeapLocationPair(block1, -1, block2, -1)).second) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return 0;
+ }
+
+ size = heapinfo1->busy_block.busy_size;
+
+ // Remember (basic) type inference.
+ // The current data structure only allows us to do this for the whole block.
+ if (type != nullptr && area1 == real_addr_block1)
+ state.types1_(block1, 0) = type;
+ if (type != nullptr && area2 == real_addr_block2)
+ state.types2_(block2, 0) = type;
+
+ if (size <= 0) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return 0;
+ }
+
+ if (heapinfo1->busy_block.ignore > 0
+ && heapinfo2->busy_block.ignore == heapinfo1->busy_block.ignore)
+ check_ignore = heapinfo1->busy_block.ignore;
+
+ } else if ((heapinfo1->type > 0) && (heapinfo2->type > 0)) { /* Fragmented block */
+
+ // Fragment number:
+ ssize_t frag1 = ((uintptr_t)(ADDR2UINT(area1) % (BLOCKSIZE))) >> heapinfo1->type;
+ ssize_t frag2 = ((uintptr_t)(ADDR2UINT(area2) % (BLOCKSIZE))) >> heapinfo2->type;
+
+ // Process address of the fragment_:
+ void* real_addr_frag1 = (void*)((char*)real_addr_block1 + (frag1 << heapinfo1->type));
+ void* real_addr_frag2 = (void*)((char*)real_addr_block2 + (frag2 << heapinfo2->type));
+
+ // Check the size of the fragments against the size of the type:
+ if (type_size != -1) {
+ if (heapinfo1->busy_frag.frag_size[frag1] == -1 || heapinfo2->busy_frag.frag_size[frag2] == -1) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return -1;
+ }
+ // ?
+ if (type_size != heapinfo1->busy_frag.frag_size[frag1]
+ || type_size != heapinfo2->busy_frag.frag_size[frag2]) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return -1;
+ }
+ }
+
+ // Check if the blocks are already matched together:
+ if (state.equals_to1_(block1, frag1).valid_ && state.equals_to2_(block2, frag2).valid_ && offset1 == offset2 &&
+ state.fragmentsEqual(block1, frag1, block2, frag2)) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return 0;
+ }
+ // Compare the size of both fragments:
+ if (heapinfo1->busy_frag.frag_size[frag1] != heapinfo2->busy_frag.frag_size[frag2]) {
+ if (type_size == -1) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return -1;
+ } else
+ return 1;
+ }
+
+ // Size of the fragment_:
+ size = heapinfo1->busy_frag.frag_size[frag1];
+
+ // Remember (basic) type inference.
+ // The current data structure only allows us to do this for the whole fragment_.
+ if (type != nullptr && area1 == real_addr_frag1)
+ state.types1_(block1, frag1) = type;
+ if (type != nullptr && area2 == real_addr_frag2)
+ state.types2_(block2, frag2) = type;
+
+ // The type of the variable is already known:
+ if (type) {
+ new_type1 = new_type2 = type;
+ }
+ // Type inference from the block type.
+ else if (state.types1_(block1, frag1) != nullptr || state.types2_(block2, frag2) != nullptr) {
+
+ offset1 = (char*)area1 - (char*)real_addr_frag1;
+ offset2 = (char*)area2 - (char*)real_addr_frag2;
+
+ if (state.types1_(block1, frag1) != nullptr && state.types2_(block2, frag2) != nullptr) {
+ new_type1 =
+ get_offset_type(real_addr_frag1, state.types1_(block1, frag1), offset1, size, snapshot1, process_index);
+ new_type2 =
+ get_offset_type(real_addr_frag2, state.types2_(block2, frag2), offset1, size, snapshot2, process_index);
+ } else if (state.types1_(block1, frag1) != nullptr) {
+ new_type1 =
+ get_offset_type(real_addr_frag1, state.types1_(block1, frag1), offset1, size, snapshot1, process_index);
+ new_type2 =
+ get_offset_type(real_addr_frag2, state.types1_(block1, frag1), offset2, size, snapshot2, process_index);
+ } else if (state.types2_(block2, frag2) != nullptr) {
+ new_type1 =
+ get_offset_type(real_addr_frag1, state.types2_(block2, frag2), offset1, size, snapshot1, process_index);
+ new_type2 =
+ get_offset_type(real_addr_frag2, state.types2_(block2, frag2), offset2, size, snapshot2, process_index);
+ } else {
+ if (match_pairs)
+ state.match_equals(previous);
+ return -1;
+ }
+
+ if (new_type1 != nullptr && new_type2 != nullptr && new_type1 != new_type2) {
+
+ type = new_type1;
+ while (type->byte_size == 0 && type->subtype != nullptr)
+ type = type->subtype;
+ new_size1 = type->byte_size;
+
+ type = new_type2;
+ while (type->byte_size == 0 && type->subtype != nullptr)
+ type = type->subtype;
+ new_size2 = type->byte_size;
+
+ } else {
+ if (match_pairs)
+ state.match_equals(previous);
+ return -1;
+ }
+ }
+
+ if (new_size1 > 0 && new_size1 == new_size2) {
+ type = new_type1;
+ size = new_size1;
+ }
+
+ if (offset1 == 0 && offset2 == 0 &&
+ not previous->insert(simgrid::mc::makeHeapLocationPair(block1, frag1, block2, frag2)).second) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return 0;
+ }
+
+ if (size <= 0) {
+ if (match_pairs)
+ state.match_equals(previous);
+ return 0;
+ }
+
+ if ((heapinfo1->busy_frag.ignore[frag1] > 0) &&
+ (heapinfo2->busy_frag.ignore[frag2] == heapinfo1->busy_frag.ignore[frag1]))
+ check_ignore = heapinfo1->busy_frag.ignore[frag1];
+
+ } else
+ return 1;
+
+
+ /* Start comparison */
+ int res_compare;
+ if (type)
+ res_compare = compare_heap_area_with_type(state, process_index, area1, area2, snapshot1, snapshot2, previous, type,
+ size, check_ignore, pointer_level);
+ else
+ res_compare = compare_heap_area_without_type(state, process_index, area1, area2, snapshot1, snapshot2, previous,
+ size, check_ignore);
+
+ if (res_compare == 1)
+ return res_compare;
+
+ if (match_pairs)
+ state.match_equals(previous);
+ return 0;
+}
+
+}
+}
+
+/************************** Snapshot comparison *******************************/
+/******************************************************************************/
+
+static int compare_areas_with_type(simgrid::mc::StateComparator& state,
+ int process_index,
+ void* real_area1, simgrid::mc::Snapshot* snapshot1, mc_mem_region_t region1,
+ void* real_area2, simgrid::mc::Snapshot* snapshot2, mc_mem_region_t region2,
+ simgrid::mc::Type* type, int pointer_level)
+{
+ simgrid::mc::RemoteClient* process = &mc_model_checker->process();
+
+ simgrid::mc::Type* subtype;
+ simgrid::mc::Type* subsubtype;
+ int elm_size;
+ int i;
+ int res;
+
+ do {
+ switch (type->type) {
+ case DW_TAG_unspecified_type:
+ return 1;
+
+ case DW_TAG_base_type:
+ case DW_TAG_enumeration_type:
+ case DW_TAG_union_type:
+ return MC_snapshot_region_memcmp(real_area1, region1, real_area2, region2, type->byte_size) != 0;
+ case DW_TAG_typedef:
+ case DW_TAG_volatile_type:
+ case DW_TAG_const_type:
+ // Poor man's TCO:
+ type = type->subtype;
+ continue; // restart
+ case DW_TAG_array_type:
+ subtype = type->subtype;
+ switch (subtype->type) {
+ case DW_TAG_unspecified_type:
+ return 1;
+
+ case DW_TAG_base_type:
+ case DW_TAG_enumeration_type:
+ case DW_TAG_pointer_type:
+ case DW_TAG_reference_type:
+ case DW_TAG_rvalue_reference_type:
+ case DW_TAG_structure_type:
+ case DW_TAG_class_type:
+ case DW_TAG_union_type:
+ if (subtype->full_type)
+ subtype = subtype->full_type;
+ elm_size = subtype->byte_size;
+ break;
+ case DW_TAG_const_type:
+ case DW_TAG_typedef:
+ case DW_TAG_volatile_type:
+ subsubtype = subtype->subtype;
+ if (subsubtype->full_type)
+ subsubtype = subsubtype->full_type;
+ elm_size = subsubtype->byte_size;
+ break;
+ default:
+ return 0;
+ break;
+ }
+ for (i = 0; i < type->element_count; i++) {
+ size_t off = i * elm_size;
+ res = compare_areas_with_type(state, process_index, (char*)real_area1 + off, snapshot1, region1,
+ (char*)real_area2 + off, snapshot2, region2, type->subtype, pointer_level);
+ if (res == 1)
+ return res;
+ }
+ break;
+ case DW_TAG_pointer_type:
+ case DW_TAG_reference_type:
+ case DW_TAG_rvalue_reference_type: {
+ void* addr_pointed1 = MC_region_read_pointer(region1, real_area1);
+ void* addr_pointed2 = MC_region_read_pointer(region2, real_area2);
+
+ if (type->subtype && type->subtype->type == DW_TAG_subroutine_type)
+ return (addr_pointed1 != addr_pointed2);
+ if (addr_pointed1 == nullptr && addr_pointed2 == nullptr)
+ return 0;
+ if (addr_pointed1 == nullptr || addr_pointed2 == nullptr)
+ return 1;
+ if (not state.compared_pointers.insert(std::make_pair(addr_pointed1, addr_pointed2)).second)
+ return 0;
+
+ pointer_level++;
+
+ // Some cases are not handled here:
+ // * the pointers lead to different areas (one to the heap, the other to the RW segment ...)
+ // * a pointer leads to the read-only segment of the current object
+ // * a pointer lead to a different ELF object
+
+ if (addr_pointed1 > process->heap_address && addr_pointed1 < mc_snapshot_get_heap_end(snapshot1)) {
+ if (not(addr_pointed2 > process->heap_address && addr_pointed2 < mc_snapshot_get_heap_end(snapshot2)))
+ return 1;
+ // The pointers are both in the heap:
+ return simgrid::mc::compare_heap_area(state, process_index, addr_pointed1, addr_pointed2, snapshot1,
+ snapshot2, nullptr, type->subtype, pointer_level);
+
+ } else if (region1->contain(simgrid::mc::remote(addr_pointed1))) {
+ // The pointers are both in the current object R/W segment:
+ if (not region2->contain(simgrid::mc::remote(addr_pointed2)))
+ return 1;
+ if (not type->type_id)
+ return (addr_pointed1 != addr_pointed2);
+ else
+ return compare_areas_with_type(state, process_index, addr_pointed1, snapshot1, region1, addr_pointed2,
+ snapshot2, region2, type->subtype, pointer_level);
+ } else {
+
+ // TODO, We do not handle very well the case where
+ // it belongs to a different (non-heap) region from the current one.
+
+ return (addr_pointed1 != addr_pointed2);
+ }
+ break;
+ }
+ case DW_TAG_structure_type:
+ case DW_TAG_class_type:
+ for (simgrid::mc::Member& member : type->members) {
+ void* member1 = simgrid::dwarf::resolve_member(real_area1, type, &member, snapshot1, process_index);
+ void* member2 = simgrid::dwarf::resolve_member(real_area2, type, &member, snapshot2, process_index);
+ mc_mem_region_t subregion1 = mc_get_region_hinted(member1, snapshot1, process_index, region1);
+ mc_mem_region_t subregion2 = mc_get_region_hinted(member2, snapshot2, process_index, region2);
+ res = compare_areas_with_type(state, process_index, member1, snapshot1, subregion1, member2, snapshot2,
+ subregion2, member.type, pointer_level);
+ if (res == 1)
+ return res;
+ }
+ break;
+ case DW_TAG_subroutine_type:
+ return -1;
+ break;
+ default:
+ XBT_VERB("Unknown case: %d", type->type);
+ break;
+ }
+
+ return 0;
+ } while (true);
+}
+
+static int compare_global_variables(
+ simgrid::mc::StateComparator& state,
+ simgrid::mc::ObjectInformation* object_info,
+ int process_index,
+ mc_mem_region_t r1, mc_mem_region_t r2,
+ simgrid::mc::Snapshot* snapshot1, simgrid::mc::Snapshot* snapshot2)
+{
+ xbt_assert(r1 && r2, "Missing region.");
+
+#if HAVE_SMPI
+ if (r1->storage_type() == simgrid::mc::StorageType::Privatized) {
+ xbt_assert(process_index >= 0);
+ if (r2->storage_type() != simgrid::mc::StorageType::Privatized)
+ return 1;
+
+ size_t process_count = MC_smpi_process_count();
+ xbt_assert(process_count == r1->privatized_data().size()
+ && process_count == r2->privatized_data().size());
+
+ // Compare the global variables separately for each simulates process:
+ for (size_t process_index = 0; process_index < process_count; process_index++) {
+ if (compare_global_variables(state,
+ object_info, process_index,
+ &r1->privatized_data()[process_index],
+ &r2->privatized_data()[process_index],
+ snapshot1, snapshot2))
+ return 1;
+ }
+ return 0;
+ }
+#else
+ xbt_assert(r1->storage_type() != simgrid::mc::StorageType::Privatized);
+#endif
+ xbt_assert(r2->storage_type() != simgrid::mc::StorageType::Privatized);
+
+ std::vector<simgrid::mc::Variable>& variables = object_info->global_variables;
+
+ for (simgrid::mc::Variable const& current_var : variables) {
+
+ // If the variable is not in this object, skip it:
+ // We do not expect to find a pointer to something which is not reachable
+ // by the global variables.
+ if ((char *) current_var.address < (char *) object_info->start_rw
+ || (char *) current_var.address > (char *) object_info->end_rw)
+ continue;
+
+ simgrid::mc::Type* bvariable_type = current_var.type;
+ int res = compare_areas_with_type(state, process_index,
+ (char *) current_var.address, snapshot1, r1,
+ (char *) current_var.address, snapshot2, r2,
+ bvariable_type, 0);
+ if (res == 1) {
+ XBT_VERB("Global variable %s (%p) is different between snapshots",
+ current_var.name.c_str(),
+ (char *) current_var.address);
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+static int compare_local_variables(simgrid::mc::StateComparator& state,
+ int process_index,
+ simgrid::mc::Snapshot* snapshot1,
+ simgrid::mc::Snapshot* snapshot2,
+ mc_snapshot_stack_t stack1,
+ mc_snapshot_stack_t stack2)
+{
+ if (stack1->local_variables.size() != stack2->local_variables.size()) {
+ XBT_VERB("Different number of local variables");
+ return 1;
+ }
+
+ unsigned int cursor = 0;
+ local_variable_t current_var1;
+ local_variable_t current_var2;
+ while (cursor < stack1->local_variables.size()) {
+ current_var1 = &stack1->local_variables[cursor];
+ current_var2 = &stack1->local_variables[cursor];
+ if (current_var1->name != current_var2->name
+ || current_var1->subprogram != current_var2->subprogram
+ || current_var1->ip != current_var2->ip) {
+ // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
+ XBT_VERB
+ ("Different name of variable (%s - %s) "
+ "or frame (%s - %s) or ip (%lu - %lu)",
+ current_var1->name.c_str(),
+ current_var2->name.c_str(),
+ current_var1->subprogram->name.c_str(),
+ current_var2->subprogram->name.c_str(),
+ current_var1->ip, current_var2->ip);
+ return 1;
+ }
+ // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
+
+ simgrid::mc::Type* subtype = current_var1->type;
+ int res = compare_areas_with_type(
+ state, process_index, current_var1->address, snapshot1,
+ mc_get_snapshot_region(current_var1->address, snapshot1, process_index), current_var2->address, snapshot2,
+ mc_get_snapshot_region(current_var2->address, snapshot2, process_index), subtype, 0);
+
+ if (res == 1) {
+ // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
+ XBT_VERB("Local variable %s (%p - %p) in frame %s "
+ "is different between snapshots",
+ current_var1->name.c_str(), current_var1->address, current_var2->address,
+ current_var1->subprogram->name.c_str());
+ return res;
+ }
+ cursor++;
+ }
+ return 0;
+}
+
+namespace simgrid {
+namespace mc {
+
+static std::unique_ptr<simgrid::mc::StateComparator> state_comparator;
+
+int snapshot_compare(int num1, simgrid::mc::Snapshot* s1, int num2, simgrid::mc::Snapshot* s2)
+{
+ // TODO, make this a field of ModelChecker or something similar
+
+ if (state_comparator == nullptr)
+ state_comparator = std::unique_ptr<StateComparator>(new StateComparator());
+ else
+ state_comparator->clear();
+
+ simgrid::mc::RemoteClient* process = &mc_model_checker->process();
+
+ int errors = 0;
+
+ int hash_result = 0;
+ if (_sg_mc_hash) {
+ hash_result = (s1->hash != s2->hash);
+ if (hash_result) {
+ XBT_VERB("(%d - %d) Different hash: 0x%" PRIx64 "--0x%" PRIx64, num1, num2, s1->hash, s2->hash);
+#ifndef MC_DEBUG
+ return 1;
+#endif
+ } else
+ XBT_VERB("(%d - %d) Same hash: 0x%" PRIx64, num1, num2, s1->hash);
+ }
+
+ /* Compare enabled processes */
+ if (s1->enabled_processes != s2->enabled_processes) {
+ XBT_VERB("(%d - %d) Different amount of enabled processes", num1, num2);
+ return 1;
+ }
+
+ /* Compare size of stacks */
+ int is_diff = 0;
+ for (unsigned long i = 0; i < s1->stacks.size(); i++) {
+ size_t size_used1 = s1->stack_sizes[i];
+ size_t size_used2 = s2->stack_sizes[i];
+ if (size_used1 != size_used2) {
+#ifdef MC_DEBUG
+ XBT_DEBUG("(%d - %d) Different size used in stacks: %zu - %zu", num1, num2, size_used1, size_used2);
+ errors++;
+ is_diff = 1;
+#else
+#ifdef MC_VERBOSE
+ XBT_VERB("(%d - %d) Different size used in stacks: %zu - %zu", num1, num2, size_used1, size_used2);
+#endif
+ return 1;
+#endif
+ }
+ }
+ if (is_diff) // do not proceed if there is any stacks that don't match
+ return 1;
+
+ /* Init heap information used in heap comparison algorithm */
+ xbt_mheap_t heap1 = (xbt_mheap_t)s1->read_bytes(
+ alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
+ remote(process->heap_address),
+ simgrid::mc::ProcessIndexMissing, simgrid::mc::ReadOptions::lazy());
+ xbt_mheap_t heap2 = (xbt_mheap_t)s2->read_bytes(
+ alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
+ remote(process->heap_address),
+ simgrid::mc::ProcessIndexMissing, simgrid::mc::ReadOptions::lazy());
+ int res_init = state_comparator->initHeapInformation(heap1, heap2, &s1->to_ignore, &s2->to_ignore);
+
+ if (res_init == -1) {
+#ifdef MC_DEBUG
+ XBT_DEBUG("(%d - %d) Different heap information", num1, num2);
+ errors++;
+#else
+#ifdef MC_VERBOSE
+ XBT_VERB("(%d - %d) Different heap information", num1, num2);
+#endif
+
+ return 1;
+#endif
+ }
+
+ /* Stacks comparison */
+ int diff_local = 0;
+ for (unsigned int cursor = 0; cursor < s1->stacks.size(); cursor++) {
+ mc_snapshot_stack_t stack1 = &s1->stacks[cursor];
+ mc_snapshot_stack_t stack2 = &s2->stacks[cursor];
+
+ if (stack1->process_index != stack2->process_index) {
+ diff_local = 1;
+ XBT_DEBUG("(%d - %d) Stacks with different process index (%i vs %i)", num1, num2,
+ stack1->process_index, stack2->process_index);
+ }
+ else diff_local = compare_local_variables(*state_comparator,
+ stack1->process_index, s1, s2, stack1, stack2);
+ if (diff_local > 0) {
+#ifdef MC_DEBUG
+ XBT_DEBUG("(%d - %d) Different local variables between stacks %d", num1,
+ num2, cursor + 1);
+ errors++;
+#else
+
+#ifdef MC_VERBOSE
+ XBT_VERB("(%d - %d) Different local variables between stacks %u", num1, num2, cursor + 1);
+#endif
+
+ return 1;
+#endif
+ }
+ }
+
+ size_t regions_count = s1->snapshot_regions.size();
+ // TODO, raise a difference instead?
+ xbt_assert(regions_count == s2->snapshot_regions.size());
+
+ for (size_t k = 0; k != regions_count; ++k) {
+ mc_mem_region_t region1 = s1->snapshot_regions[k].get();
+ mc_mem_region_t region2 = s2->snapshot_regions[k].get();
+
+ // Preconditions:
+ if (region1->region_type() != simgrid::mc::RegionType::Data)
+ continue;
+
+ xbt_assert(region1->region_type() == region2->region_type());
+ xbt_assert(region1->object_info() == region2->object_info());
+ xbt_assert(region1->object_info());
+
+ std::string const& name = region1->object_info()->file_name;
+
+ /* Compare global variables */
+ if (compare_global_variables(*state_comparator, region1->object_info(), simgrid::mc::ProcessIndexDisabled, region1,
+ region2, s1, s2)) {
+
+#ifdef MC_DEBUG
+ XBT_DEBUG("(%d - %d) Different global variables in %s",
+ num1, num2, name.c_str());
+ errors++;
+#else
+#ifdef MC_VERBOSE
+ XBT_VERB("(%d - %d) Different global variables in %s",
+ num1, num2, name.c_str());
+#endif
+
+ return 1;
+#endif
+ }
+ }
+
+ /* Compare heap */
+ if (simgrid::mc::mmalloc_compare_heap(*state_comparator, s1, s2) > 0) {
+
+#ifdef MC_DEBUG
+ XBT_DEBUG("(%d - %d) Different heap (mmalloc_compare)", num1, num2);
+ errors++;
+#else
+
+#ifdef MC_VERBOSE
+ XBT_VERB("(%d - %d) Different heap (mmalloc_compare)", num1, num2);
+#endif
+ return 1;
+#endif
+ }
+
+#ifdef MC_VERBOSE
+ if (errors || hash_result)
+ XBT_VERB("(%d - %d) Difference found", num1, num2);
+ else
+ XBT_VERB("(%d - %d) No difference found", num1, num2);
+#endif
+
+#if defined(MC_DEBUG) && defined(MC_VERBOSE)
+ if (_sg_mc_hash) {
+ // * false positive SHOULD be avoided.
+ // * There MUST not be any false negative.
+
+ XBT_VERB("(%d - %d) State equality hash test is %s %s", num1, num2,
+ (hash_result != 0) == (errors != 0) ? "true" : "false", not hash_result ? "positive" : "negative");
+ }
+#endif
+
+ return errors > 0 || hash_result;
+}
+
+}
+}
--- /dev/null
+/* Copyright (c) 2008-2018. The SimGrid Team.
+ * All rights reserved. */
+
+/* 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 <unistd.h>
+
+#include <cstring>
+#include <dirent.h>
+#include <fcntl.h>
+#include <link.h>
+
+#ifndef WIN32
+#include <sys/mman.h>
+#endif
+
+#include "src/internal_config.h"
+#include "src/mc/mc_private.hpp"
+#include "src/smpi/include/private.hpp"
+#include "xbt/file.hpp"
+#include "xbt/mmalloc.h"
+#include "xbt/module.h"
+
+#include "src/xbt/mmalloc/mmprivate.h"
+
+#include "src/simix/smx_private.hpp"
+
+#include <libunwind.h>
+#include <libelf.h>
+
+#include "src/mc/mc_private.hpp"
+#include <mc/mc.h>
+
+#include "src/mc/mc_config.hpp"
+#include "src/mc/mc_hash.hpp"
+#include "src/mc/mc_mmu.hpp"
+#include "src/mc/mc_smx.hpp"
+#include "src/mc/mc_snapshot.hpp"
+#include "src/mc/mc_unw.hpp"
+#include "src/mc/remote/mc_protocol.h"
+
+#include "src/mc/RegionSnapshot.hpp"
+#include "src/mc/ObjectInformation.hpp"
+#include "src/mc/Frame.hpp"
+#include "src/mc/Variable.hpp"
+
+using simgrid::mc::remote;
+
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_checkpoint, mc, "Logging specific to mc_checkpoint");
+
+#define PROT_RWX (PROT_READ | PROT_WRITE | PROT_EXEC)
+#define PROT_RW (PROT_READ | PROT_WRITE)
+#define PROT_RX (PROT_READ | PROT_EXEC)
+
+namespace simgrid {
+namespace mc {
+
+/************************************ Free functions **************************************/
+/*****************************************************************************************/
+
+/** @brief Restore a region from a snapshot
+ *
+ * @param region Target region
+ */
+static void restore(mc_mem_region_t region)
+{
+ switch(region->storage_type()) {
+ case simgrid::mc::StorageType::Flat:
+ mc_model_checker->process().write_bytes(region->flat_data().get(),
+ region->size(), region->permanent_address());
+ break;
+
+ case simgrid::mc::StorageType::Chunked:
+ mc_region_restore_sparse(&mc_model_checker->process(), region);
+ break;
+
+ case simgrid::mc::StorageType::Privatized:
+ for (auto& p : region->privatized_data())
+ restore(&p);
+ break;
+
+ default: // includes StorageType::NoData
+ xbt_die("Storage type not supported");
+ break;
+ }
+}
+
+#if HAVE_SMPI
+RegionSnapshot privatized_region(
+ RegionType region_type, void *start_addr, void* permanent_addr,
+ std::size_t size
+ )
+{
+ size_t process_count = MC_smpi_process_count();
+
+ // Read smpi_privatization_regions from MCed:
+ smpi_privatization_region_t remote_smpi_privatization_regions;
+ mc_model_checker->process().read_variable(
+ "smpi_privatization_regions",
+ &remote_smpi_privatization_regions, sizeof(remote_smpi_privatization_regions));
+ s_smpi_privatization_region_t privatization_regions[process_count];
+ mc_model_checker->process().read_bytes(
+ &privatization_regions, sizeof(privatization_regions),
+ remote(remote_smpi_privatization_regions));
+
+ std::vector<simgrid::mc::RegionSnapshot> data;
+ data.reserve(process_count);
+ for (size_t i = 0; i < process_count; i++)
+ data.push_back(simgrid::mc::region(region_type, start_addr,
+ privatization_regions[i].address, size));
+
+ simgrid::mc::RegionSnapshot region = simgrid::mc::RegionSnapshot(
+ region_type, start_addr, permanent_addr, size);
+ region.privatized_data(std::move(data));
+ return region;
+}
+#endif
+
+static
+void add_region(int index, simgrid::mc::Snapshot* snapshot,
+ simgrid::mc::RegionType type,
+ simgrid::mc::ObjectInformation* object_info,
+ void *start_addr, void* permanent_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->snapshot_regions[index]
+ = std::unique_ptr<simgrid::mc::RegionSnapshot>(
+ new simgrid::mc::RegionSnapshot(std::move(region)));
+}
+
+static void get_memory_regions(simgrid::mc::RemoteClient* process, simgrid::mc::Snapshot* snapshot)
+{
+ const size_t n = process->object_infos.size();
+ snapshot->snapshot_regions.resize(n + 1);
+ int i = 0;
+ for (auto const& object_info : process->object_infos)
+ add_region(i++, snapshot, simgrid::mc::RegionType::Data,
+ object_info.get(),
+ object_info->start_rw, 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(n, snapshot, simgrid::mc::RegionType::Heap, nullptr,
+ start_heap, start_heap,
+ (char *) end_heap - (char *) start_heap);
+ snapshot->heap_bytes_used = mmalloc_get_bytes_used_remote(
+ heap->heaplimit,
+ process->get_malloc_info());
+
+#if HAVE_SMPI
+ if (mc_model_checker->process().privatized() && MC_smpi_process_count())
+ // snapshot->privatization_index = smpi_loaded_page
+ mc_model_checker->process().read_variable(
+ "smpi_loaded_page", &snapshot->privatization_index,
+ sizeof(snapshot->privatization_index));
+ else
+#endif
+ snapshot->privatization_index = simgrid::mc::ProcessIndexMissing;
+}
+
+/** \brief Fills the position of the segments (executable, read-only, read/write).
+ * */
+// TODO, use the ELF segment information for more robustness
+void find_object_address(
+ std::vector<simgrid::xbt::VmMap> const& maps,
+ simgrid::mc::ObjectInformation* result)
+{
+ std::string name = simgrid::xbt::Path(result->file_name).get_base_name();
+
+ for (size_t i = 0; i < maps.size(); ++i) {
+ simgrid::xbt::VmMap const& reg = maps[i];
+ if (maps[i].pathname.empty())
+ continue;
+ std::string map_basename = simgrid::xbt::Path(maps[i].pathname).get_base_name();
+ if (map_basename != name)
+ continue;
+
+ // This is the non-GNU_RELRO-part of the data segment:
+ if (reg.prot == PROT_RW) {
+ xbt_assert(not result->start_rw, "Multiple read-write segments for %s, not supported", maps[i].pathname.c_str());
+ result->start_rw = (char*) reg.start_addr;
+ result->end_rw = (char*) reg.end_addr;
+
+ // The next VMA might be end of the data segment:
+ if (i + 1 < maps.size()
+ && maps[i + 1].pathname.empty()
+ && maps[i + 1].prot == PROT_RW
+ && maps[i + 1].start_addr == reg.end_addr)
+ result->end_rw = (char*) maps[i + 1].end_addr;
+ }
+
+ // This is the text segment:
+ else if (reg.prot == PROT_RX) {
+ xbt_assert(not result->start_exec, "Multiple executable segments for %s, not supported",
+ maps[i].pathname.c_str());
+ result->start_exec = (char*) reg.start_addr;
+ result->end_exec = (char*) reg.end_addr;
+
+ // The next VMA might be end of the data segment:
+ if (i + 1 < maps.size()
+ && maps[i + 1].pathname.empty()
+ && maps[i + 1].prot == PROT_RW
+ && maps[i + 1].start_addr == reg.end_addr) {
+ result->start_rw = (char*) maps[i + 1].start_addr;
+ result->end_rw = (char*) maps[i + 1].end_addr;
+ }
+ }
+
+ // This is the GNU_RELRO-part of the data segment:
+ else if (reg.prot == PROT_READ) {
+ xbt_assert(not result->start_ro, "Multiple read only segments for %s, not supported", maps[i].pathname.c_str());
+ result->start_ro = (char*) reg.start_addr;
+ result->end_ro = (char*) reg.end_addr;
+ }
+ }
+
+ result->start = result->start_rw;
+ if ((const void*) result->start_ro < result->start)
+ result->start = result->start_ro;
+ if ((const void*) result->start_exec < result->start)
+ result->start = result->start_exec;
+
+ result->end = result->end_rw;
+ if (result->end_ro && (const void*) result->end_ro > result->end)
+ result->end = result->end_ro;
+ if (result->end_exec && (const void*) result->end_exec > result->end)
+ result->end = result->end_exec;
+
+ xbt_assert(result->start_exec || result->start_rw || result->start_ro);
+}
+
+/************************************* Take Snapshot ************************************/
+/****************************************************************************************/
+
+/** \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, int process_index,
+ std::vector<s_local_variable_t>& result)
+{
+ simgrid::mc::RemoteClient* process = &mc_model_checker->process();
+
+ 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;
+
+ int region_type;
+ // FIXME, get rid of `region_type`
+ if ((long) stack_frame->ip > (long) process->libsimgrid_info->start_exec)
+ region_type = 1;
+ else
+ region_type = 2;
+
+ 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.region = region_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(), process_index);
+
+ 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, process_index, result);
+}
+
+static std::vector<s_local_variable_t> get_local_variables_values(std::vector<s_mc_stack_frame_t>& stack_frames,
+ int process_index)
+{
+ 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, process_index, 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;
+
+ 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_sysv_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");
+ }
+
+ if (result.empty()) {
+ XBT_INFO("unw_init_local failed");
+ xbt_abort();
+ }
+
+ return result;
+}
+
+static std::vector<s_mc_snapshot_stack_t> take_snapshot_stacks(simgrid::mc::Snapshot* snapshot)
+{
+ std::vector<s_mc_snapshot_stack_t> res;
+
+ for (auto const& stack : mc_model_checker->process().stack_areas()) {
+ s_mc_snapshot_stack_t st;
+
+ // Read the context from remote process:
+ unw_context_t context;
+ mc_model_checker->process().read_bytes(
+ &context, sizeof(context), remote(stack.context));
+
+ st.context.initialize(&mc_model_checker->process(), &context);
+
+ st.stack_frames = unwind_stack_frames(&st.context);
+ st.local_variables = get_local_variables_values(st.stack_frames, stack.process_index);
+ st.process_index = stack.process_index;
+
+ unw_word_t sp = st.stack_frames[0].sp;
+
+ res.push_back(std::move(st));
+
+ size_t stack_size =
+ (char*) stack.address + stack.size - (char*) sp;
+ snapshot->stack_sizes.push_back(stack_size);
+ }
+
+ return res;
+
+}
+
+static void snapshot_handle_ignore(simgrid::mc::Snapshot* snapshot)
+{
+ xbt_assert(snapshot->process());
+
+ // Copy the memory:
+ for (auto const& region : mc_model_checker->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),
+ simgrid::mc::ProcessIndexDisabled);
+ snapshot->ignored_data.push_back(std::move(ignored_data));
+ }
+
+ // Zero the memory:
+ for (auto const& region : mc_model_checker->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));
+}
+
+static std::vector<s_fd_infos_t> get_current_fds(pid_t pid)
+{
+ const size_t fd_dir_path_size = 20;
+ char fd_dir_path[fd_dir_path_size];
+ int res = snprintf(fd_dir_path, fd_dir_path_size,
+ "/proc/%lli/fd", (long long int) pid);
+ xbt_assert(res >= 0);
+ if ((size_t) res > fd_dir_path_size)
+ xbt_die("Unexpected buffer is too small for fd_dir_path");
+
+ DIR* fd_dir = opendir(fd_dir_path);
+ if (fd_dir == nullptr)
+ xbt_die("Cannot open directory '/proc/self/fd'\n");
+
+ std::vector<s_fd_infos_t> fds;
+
+ struct dirent* fd_number;
+ while ((fd_number = readdir(fd_dir))) {
+
+ int fd_value = xbt_str_parse_int(fd_number->d_name, "Found a non-numerical FD: %s. Freaking out!");
+
+ if(fd_value < 3)
+ continue;
+
+ const size_t source_size = 25;
+ char source[25];
+ int res = snprintf(source, source_size, "/proc/%lli/fd/%s",
+ (long long int) pid, fd_number->d_name);
+ xbt_assert(res >= 0);
+ if ((size_t) res > source_size)
+ xbt_die("Unexpected buffer is too small for fd %s", fd_number->d_name);
+
+ const size_t link_size = 200;
+ char link[200];
+ res = readlink(source, link, link_size);
+
+ if (res<0)
+ xbt_die("Could not read link for %s", source);
+ if (res==200)
+ xbt_die("Buffer to small for link of %s", source);
+
+ link[res] = '\0';
+
+#if HAVE_SMPI
+ if(smpi_is_privatization_file(link))
+ continue;
+#endif
+
+ // This is (probably) the DIR* we are reading:
+ // TODO, read all the file entries at once and close the DIR.*
+ if(strcmp(fd_dir_path, link) == 0)
+ continue;
+
+ // We don't handle them.
+ // It does not mean we should silently ignore them however.
+ if (strncmp(link, "pipe:", std::strlen("pipe:")) == 0 || strncmp(link, "socket:", std::strlen("socket:")) == 0)
+ continue;
+
+ // If dot_output enabled, do not handle the corresponding file
+ if (dot_output != nullptr) {
+ std::string link_basename = simgrid::xbt::Path(link).get_base_name();
+ if (link_basename == _sg_mc_dot_output_file.get())
+ continue;
+ }
+
+ // This is probably a shared memory used by lttng-ust:
+ if(strncmp("/dev/shm/ust-shm-tmp-", link, std::strlen("/dev/shm/ust-shm-tmp-"))==0)
+ continue;
+
+ // Add an entry for this FD in the snapshot:
+ s_fd_infos_t fd;
+ fd.filename = std::string(link);
+ fd.number = fd_value;
+ fd.flags = fcntl(fd_value, F_GETFL) | fcntl(fd_value, F_GETFD) ;
+ fd.current_position = lseek(fd_value, 0, SEEK_CUR);
+ fds.push_back(std::move(fd));
+ }
+
+ closedir (fd_dir);
+ return fds;
+}
+
+std::shared_ptr<simgrid::mc::Snapshot> take_snapshot(int num_state)
+{
+ XBT_DEBUG("Taking snapshot %i", num_state);
+
+ simgrid::mc::RemoteClient* mc_process = &mc_model_checker->process();
+
+ std::shared_ptr<simgrid::mc::Snapshot> snapshot = std::make_shared<simgrid::mc::Snapshot>(mc_process, num_state);
+
+ for (auto const& p : mc_model_checker->process().actors())
+ snapshot->enabled_processes.insert(p.copy.getBuffer()->pid);
+
+ snapshot_handle_ignore(snapshot.get());
+
+ if (_sg_mc_snapshot_fds)
+ snapshot->current_fds = get_current_fds(mc_model_checker->process().pid());
+
+ /* Save the std heap and the writable mapped pages of libsimgrid and binary */
+ get_memory_regions(mc_process, snapshot.get());
+
+ snapshot->to_ignore = mc_model_checker->process().ignored_heap();
+
+ if (_sg_mc_max_visited_states > 0 || not _sg_mc_property_file.get().empty()) {
+ snapshot->stacks = take_snapshot_stacks(snapshot.get());
+ if (_sg_mc_hash)
+ snapshot->hash = simgrid::mc::hash(*snapshot);
+ else
+ snapshot->hash = 0;
+ } else
+ snapshot->hash = 0;
+
+ snapshot_ignore_restore(snapshot.get());
+ return snapshot;
+}
+
+static inline
+void restore_snapshot_regions(simgrid::mc::Snapshot* snapshot)
+{
+ for (std::unique_ptr<s_mc_mem_region_t> const& region : snapshot->snapshot_regions) {
+ // For privatized, variables we decided it was not necessary to take the snapshot:
+ if (region)
+ restore(region.get());
+ }
+
+#if HAVE_SMPI
+ if(snapshot->privatization_index >= 0) {
+ // Fix the privatization mmap:
+ s_mc_message_restore_t message{MC_MESSAGE_RESTORE, snapshot->privatization_index};
+ mc_model_checker->process().getChannel().send(message);
+ }
+#endif
+}
+
+static inline
+void restore_snapshot_fds(simgrid::mc::Snapshot* snapshot)
+{
+ xbt_die("FD snapshot not implemented in client/server mode.");
+
+ for (auto const& fd : snapshot->current_fds) {
+
+ int new_fd = open(fd.filename.c_str(), fd.flags);
+ if (new_fd < 0)
+ xbt_die("Could not reopen the file %s fo restoring the file descriptor", fd.filename.c_str());
+ if (new_fd != fd.number) {
+ dup2(new_fd, fd.number);
+ close(new_fd);
+ }
+ lseek(fd.number, fd.current_position, SEEK_SET);
+ }
+}
+
+void restore_snapshot(std::shared_ptr<simgrid::mc::Snapshot> snapshot)
+{
+ XBT_DEBUG("Restore snapshot %i", snapshot->num_state);
+ restore_snapshot_regions(snapshot.get());
+ if (_sg_mc_snapshot_fds)
+ restore_snapshot_fds(snapshot.get());
+ snapshot_ignore_restore(snapshot.get());
+ mc_model_checker->process().clear_cache();
+}
+
+}
+}
+
+#ifdef SIMGRID_TEST
+
+/* **BOOST** */
+#define BOOST_TEST_MODULE checkpoint
+#define BOOST_TEST_DYN_LINK
+#include <boost/test/unit_test.hpp>
+
+static
+void add_region(int index, simgrid::mc::Snapshot* snapshot,
+ simgrid::mc::RegionType type,
+ simgrid::mc::ObjectInformation* object_info,
+ void *start_addr, void* permanent_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->snapshot_regions[index]
+ = std::unique_ptr<simgrid::mc::RegionSnapshot>(
+ new simgrid::mc::RegionSnapshot(std::move(region)));
+}
+
+/*
+add_region test
+*/
+static
+int add_region_BOOST()
+{
+
+ RemoteClient* this_process = new RemoteClient(getpid(), -1);
+ /* read /proc/getpid()/maps into "this_process->memory_map", etc. */
+ this_process->init();
+ simgrid::mc::Snapshot* snapshot = new simgrid::mc::Snapshot(this_process, 0); // first ckpt
+ simgrid::mc::RegionType type = simgrid::mc::RegionType::Unknown;
+ // simgrid::mc::ObjectInformation* object_info;
+ /* TODO: mmap some memory to use */
+ void* start_addr = 0x7fb7539a0000; // random addr
+ void* permanent_addr = 0x7fb7539a0000; // random addr
+ std::size_t size = 4096; // PAGESIZE
+ int region_num = 10;
+ for(int i=0; i<region_num; ++i) {
+ add_region(i, snaphot, type, NULL, start_addr, permanent_addr, size);
+ }
+ BOOST_TEST(snapshot.size == 10);
+ BOOST_TEST(snapshot[0] == snapshot[7]);
+ return 1; // just for testing
+}
+
+
+BOOST_AUTO_TEST_SUITE(checkpoint)
+BOOST_AUTO_TEST_CASE(add_region_test) {
+ BOOST_TEST(add_region_BOOST() == 1);
+}
+BOOST_AUTO_TEST_SUITE_END()
+
+#endif // SIMGRID_TEST
--- /dev/null
+/* Copyright (c) 2015-2018. The SimGrid Team. All rights reserved. */
+
+/* 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. */
+
+#ifndef SIMGRID_MC_IGNORE_HPP
+#define SIMGRID_MC_IGNORE_HPP
+
+#include "src/internal_config.h"
+
+#if HAVE_UCONTEXT_H
+#include <ucontext.h> /* context relative declarations */
+
+XBT_PUBLIC void MC_register_stack_area(void* stack, smx_actor_t process, ucontext_t* context, size_t size);
+
+#endif
+
+#endif
--- /dev/null
+/* Copyright (c) 2014-2018. The SimGrid Team. All rights reserved. */
+
+/* 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. */
+
+#ifndef SIMGRID_MC_MMU_HPP
+#define SIMGRID_MC_MMU_HPP
+
+#include "xbt/misc.h" // xbt_pagesize...
+#include <cstdint>
+#include <utility>
+
+namespace simgrid {
+namespace mc {
+// TODO, do not depend on xbt_pagesize/xbt_pagebits but our own chunk size
+namespace mmu {
+
+static int chunkSize()
+{
+ return xbt_pagesize;
+}
+
+/** @brief How many memory pages are necessary to store size bytes?
+ *
+ * @param size Byte size
+ * @return Number of memory pages
+ */
+static XBT_ALWAYS_INLINE std::size_t chunkCount(std::size_t size)
+{
+ size_t page_count = size >> xbt_pagebits;
+ if (size & (xbt_pagesize - 1))
+ page_count++;
+ return page_count;
+}
+
+/** @brief Split into chunk number and remaining offset */
+static XBT_ALWAYS_INLINE std::pair<std::size_t, std::uintptr_t> split(std::uintptr_t offset)
+{
+ return {offset >> xbt_pagebits, offset & (xbt_pagesize - 1)};
+}
+
+/** Merge chunk number and remaining offset info a global offset */
+static XBT_ALWAYS_INLINE std::uintptr_t join(std::size_t page, std::uintptr_t offset)
+{
+ return ((std::uintptr_t)page << xbt_pagebits) + offset;
+}
+
+static XBT_ALWAYS_INLINE std::uintptr_t join(std::pair<std::size_t, std::uintptr_t> value)
+{
+ return join(value.first, value.second);
+}
+
+static XBT_ALWAYS_INLINE bool sameChunk(std::uintptr_t a, std::uintptr_t b)
+{
+ return (a >> xbt_pagebits) == (b >> xbt_pagebits);
+}
+}
+}
+}
+
+#endif
--- /dev/null
+/* Copyright (c) 2014-2018. The SimGrid Team.
+ * All rights reserved. */
+
+/* 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. */
+
+/* MC interface: definitions that non-MC modules must see, but not the user */
+
+
+#include <unistd.h> // pread, pwrite
+
+#include "src/mc/PageStore.hpp"
+#include "src/mc/mc_mmu.hpp"
+#include "src/mc/mc_private.hpp"
+#include "src/mc/mc_snapshot.hpp"
+
+#include <xbt/mmalloc.h>
+#include "src/mc/ChunkedData.hpp"
+
+using simgrid::mc::remote;
+
+/** @brief Restore a snapshot of a region
+ *
+ * If possible, the restoration will be incremental
+ * (the modified pages will not be touched).
+ *
+ * @param start_addr
+ * @param page_count Number of pages of the region
+ * @param pagenos
+ */
+void mc_restore_page_snapshot_region(simgrid::mc::RemoteClient* process, void* start_addr,
+ simgrid::mc::ChunkedData const& pages_copy)
+{
+ for (size_t i = 0; i != pages_copy.page_count(); ++i) {
+ // Otherwise, copy the page:
+ void* target_page = (void*) simgrid::mc::mmu::join(i, (std::uintptr_t) start_addr);
+ const void* source_page = pages_copy.page(i);
+ process->write_bytes(source_page, xbt_pagesize, remote(target_page));
+ }
+}
+
+// ***** High level API
+
+void mc_region_restore_sparse(simgrid::mc::RemoteClient* process, mc_mem_region_t reg)
+{
+ xbt_assert(((reg->permanent_address().address()) & (xbt_pagesize-1)) == 0,
+ "Not at the beginning of a page");
+ xbt_assert(simgrid::mc::mmu::chunkCount(reg->size()) == reg->page_data().page_count());
+ mc_restore_page_snapshot_region(process,
+ (void*) reg->permanent_address().address(), reg->page_data());
+}
--- /dev/null
+/* Copyright (c) 2014-2018. The SimGrid Team.
+ * All rights reserved. */
+
+/* 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 <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/PageStore.hpp"
+#include "src/mc/mc_mmu.hpp"
+#include "src/mc/mc_private.hpp"
+#include "src/mc/mc_snapshot.hpp"
+
+/** @brief Find the snapshoted region from a pointer
+ *
+ * @param addr Pointer
+ * @param snapshot Snapshot
+ * @param Snapshot region in the snapshot this pointer belongs to
+ * (or nullptr if it does not belong to any snapshot region)
+ * */
+mc_mem_region_t mc_get_snapshot_region(
+ const void* addr, const simgrid::mc::Snapshot* snapshot, int process_index)
+{
+ size_t n = snapshot->snapshot_regions.size();
+ for (size_t i = 0; i != n; ++i) {
+ mc_mem_region_t region = snapshot->snapshot_regions[i].get();
+ 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 = snapshot->privatization_index;
+ if (process_index < 0)
+ xbt_die("Missing process index");
+ if (process_index >= (int) region->privatized_data().size())
+ xbt_die("Invalid process index");
+ simgrid::mc::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;
+ }
+
+ return nullptr;
+}
+
+/** @brief Read memory from a snapshot region broken across fragmented pages
+ *
+ * @param addr Process (non-snapshot) address of the data
+ * @param region Snapshot memory region where the data is located
+ * @param target Buffer to store the value
+ * @param size Size of the data to read in bytes
+ * @return Pointer where the data is located (target buffer of original location)
+ */
+const void* MC_region_read_fragmented(mc_mem_region_t region, void* target, const void* addr, size_t size)
+{
+ // Last byte of the memory area:
+ void* end = (char*) addr + size - 1;
+
+ // TODO, we assume the chunks are aligned to natural chunk boundaries.
+ // We should remove this assumption.
+
+ // Page of the last byte of the memory area:
+ size_t page_end = simgrid::mc::mmu::split((std::uintptr_t) end).first;
+
+ void* dest = target;
+
+ if (dest==nullptr)
+ xbt_die("Missing destination buffer for fragmented memory access");
+
+ // 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* 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);
+ addr = (char*) addr + readable;
+ dest = (char*) dest + readable;
+ size -= readable;
+ }
+
+ // Read the end:
+ void* snapshot_addr = mc_translate_address_region_chunked((uintptr_t)addr, region);
+ memcpy(dest, snapshot_addr, size);
+
+ return target;
+}
+
+/** 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;
+ 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;
+}
+
+namespace simgrid {
+namespace mc {
+
+Snapshot::Snapshot(RemoteClient* process, int _num_state)
+ : AddressSpace(process)
+ , num_state(_num_state)
+ , heap_bytes_used(0)
+ , enabled_processes()
+ , privatization_index(0)
+ , hash(0)
+{
+
+}
+
+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);
+}
+
+}
+}
+
+#ifdef SIMGRID_TEST
+
+#include <cstdlib>
+#include <cstring>
+
+#include <sys/mman.h>
+
+#include "src/mc/mc_config.hpp"
+#include "src/mc/mc_mmu.hpp"
+#include "src/mc/mc_private.hpp"
+#include "src/mc/mc_snapshot.hpp"
+
+XBT_TEST_SUITE("mc_snapshot", "Snapshots");
+
+static inline void init_memory(void* mem, size_t size)
+{
+ char* dest = (char*) mem;
+ for (size_t i = 0; i < size; ++i) {
+ dest[i] = rand() & 255;
+ }
+}
+
+static void test_snapshot(bool sparse_checkpoint);
+
+XBT_TEST_UNIT("flat_snapshot", test_flat_snapshots, "Test flat snapshots")
+{
+ test_snapshot(0);
+}
+
+XBT_TEST_UNIT("page_snapshots", test_per_snpashots, "Test per-page snapshots")
+{
+ test_snapshot(1);
+}
+
+static void test_snapshot(bool sparse_checkpoint) {
+
+ xbt_test_add("Initialization");
+ _sg_mc_sparse_checkpoint = sparse_checkpoint;
+ xbt_assert(xbt_pagesize == getpagesize());
+ xbt_assert(1 << xbt_pagebits == xbt_pagesize);
+
+ std::unique_ptr<simgrid::mc::RemoteClient> process(new simgrid::mc::RemoteClient(getpid(), -1));
+ process->init();
+ mc_model_checker = new ::simgrid::mc::ModelChecker(std::move(process));
+
+ for(int n=1; n!=256; ++n) {
+
+ // Store region page(s):
+ size_t byte_size = n * xbt_pagesize;
+ void* source = mmap(nullptr, 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);
+ 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);
+
+ void* destination = mmap(nullptr, 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(not 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(not 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(
+ not 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);
+ 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 = nullptr;
+}
+
+#endif /* SIMGRID_TEST */
+
--- /dev/null
+/* Copyright (c) 2007-2018. The SimGrid Team. All rights reserved. */
+
+/* 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. */
+
+#ifndef SIMGRID_MC_SNAPSHOT_HPP
+#define SIMGRID_MC_SNAPSHOT_HPP
+
+#include <memory>
+#include <set>
+#include <string>
+#include <vector>
+
+#include "src/mc/ModelChecker.hpp"
+#include "src/mc/RegionSnapshot.hpp"
+#include "src/mc/mc_forward.hpp"
+#include "src/mc/mc_unw.hpp"
+
+// ***** Snapshot region
+
+XBT_PRIVATE void mc_region_restore_sparse(simgrid::mc::RemoteClient* process, mc_mem_region_t reg);
+
+static XBT_ALWAYS_INLINE void* mc_translate_address_region_chunked(uintptr_t addr, mc_mem_region_t region)
+{
+ auto split = simgrid::mc::mmu::split(addr - region->start().address());
+ auto pageno = split.first;
+ auto offset = split.second;
+ const void* snapshot_page = region->page_data().page(pageno);
+ return (char*)snapshot_page + offset;
+}
+
+static XBT_ALWAYS_INLINE void* mc_translate_address_region(uintptr_t addr, mc_mem_region_t region, int process_index)
+{
+ switch (region->storage_type()) {
+ case simgrid::mc::StorageType::Flat: {
+ uintptr_t offset = (uintptr_t)addr - (uintptr_t)region->start().address();
+ return (void*)((uintptr_t)region->flat_data().get() + offset);
+ }
+ case simgrid::mc::StorageType::Chunked:
+ return mc_translate_address_region_chunked(addr, region);
+ case simgrid::mc::StorageType::Privatized: {
+ xbt_assert(process_index >= 0, "Missing process index for privatized region");
+ xbt_assert((size_t)process_index < region->privatized_data().size(), "Out of range process index");
+ simgrid::mc::RegionSnapshot& subregion = region->privatized_data()[process_index];
+ return mc_translate_address_region(addr, &subregion, process_index);
+ }
+ default: // includes StorageType::NoData
+ xbt_die("Storage type not supported");
+ }
+}
+
+XBT_PRIVATE mc_mem_region_t mc_get_snapshot_region(const void* addr, const simgrid::mc::Snapshot* snapshot,
+ int process_index);
+
+// ***** MC Snapshot
+
+/** Ignored data
+ *
+ * Some parts of the snapshot are ignored by zeroing them out: the real
+ * values is stored here.
+ * */
+struct s_mc_snapshot_ignored_data_t {
+ void* start;
+ std::vector<char> data;
+};
+
+struct s_fd_infos_t {
+ std::string filename;
+ int number;
+ off_t current_position;
+ int flags;
+};
+
+/** Information about a given stack frame */
+struct s_mc_stack_frame_t {
+ /** Instruction pointer */
+ unw_word_t ip;
+ /** Stack pointer */
+ unw_word_t sp;
+ unw_word_t frame_base;
+ simgrid::mc::Frame* frame;
+ std::string frame_name;
+ unw_cursor_t unw_cursor;
+};
+typedef s_mc_stack_frame_t* mc_stack_frame_t;
+
+struct s_local_variable_t {
+ simgrid::mc::Frame* subprogram;
+ unsigned long ip;
+ std::string name;
+ simgrid::mc::Type* type;
+ void* address;
+ int region;
+};
+typedef s_local_variable_t* local_variable_t;
+
+struct XBT_PRIVATE s_mc_snapshot_stack_t {
+ std::vector<s_local_variable_t> local_variables;
+ simgrid::mc::UnwindContext context;
+ std::vector<s_mc_stack_frame_t> stack_frames;
+ int process_index;
+};
+typedef s_mc_snapshot_stack_t* mc_snapshot_stack_t;
+
+namespace simgrid {
+namespace mc {
+
+class XBT_PRIVATE Snapshot final : public AddressSpace {
+public:
+ Snapshot(RemoteClient* process, int num_state);
+ ~Snapshot() = default;
+ const void* read_bytes(void* buffer, std::size_t size, RemotePtr<void> address, int process_index = ProcessIndexAny,
+ ReadOptions options = ReadOptions::none()) const override;
+
+ // To be private
+ int num_state;
+ std::size_t heap_bytes_used;
+ std::vector<std::unique_ptr<s_mc_mem_region_t>> snapshot_regions;
+ std::set<pid_t> enabled_processes;
+ int privatization_index;
+ std::vector<std::size_t> stack_sizes;
+ std::vector<s_mc_snapshot_stack_t> stacks;
+ std::vector<simgrid::mc::IgnoredHeapRegion> to_ignore;
+ std::uint64_t hash;
+ std::vector<s_mc_snapshot_ignored_data_t> ignored_data;
+ std::vector<s_fd_infos_t> current_fds;
+};
+}
+}
+
+static XBT_ALWAYS_INLINE mc_mem_region_t mc_get_region_hinted(void* addr, simgrid::mc::Snapshot* snapshot,
+ int process_index, mc_mem_region_t region)
+{
+ if (region->contain(simgrid::mc::remote(addr)))
+ return region;
+ else
+ return mc_get_snapshot_region(addr, snapshot, process_index);
+}
+
+static const void* mc_snapshot_get_heap_end(simgrid::mc::Snapshot* snapshot);
+
+namespace simgrid {
+namespace mc {
+
+XBT_PRIVATE std::shared_ptr<simgrid::mc::Snapshot> take_snapshot(int num_state);
+XBT_PRIVATE void restore_snapshot(std::shared_ptr<simgrid::mc::Snapshot> snapshot);
+}
+}
+
+XBT_PRIVATE void mc_restore_page_snapshot_region(simgrid::mc::RemoteClient* process, void* start_addr,
+ simgrid::mc::ChunkedData const& pagenos);
+
+const void* MC_region_read_fragmented(mc_mem_region_t region, void* target, const void* addr, std::size_t size);
+
+int MC_snapshot_region_memcmp(const void* addr1, mc_mem_region_t region1, const void* addr2, mc_mem_region_t region2,
+ std::size_t size);
+
+static XBT_ALWAYS_INLINE const void* mc_snapshot_get_heap_end(simgrid::mc::Snapshot* snapshot)
+{
+ if (snapshot == nullptr)
+ xbt_die("snapshot is nullptr");
+ return mc_model_checker->process().get_heap()->breakval;
+}
+
+/** @brief Read memory from a snapshot region
+ *
+ * @param addr Process (non-snapshot) address of the data
+ * @param region Snapshot memory region where the data is located
+ * @param target Buffer to store the value
+ * @param size Size of the data to read in bytes
+ * @return Pointer where the data is located (target buffer of original location)
+ */
+static XBT_ALWAYS_INLINE const void* MC_region_read(mc_mem_region_t region, void* target, const void* addr,
+ std::size_t size)
+{
+ xbt_assert(region);
+
+ std::uintptr_t offset = (std::uintptr_t)addr - (std::uintptr_t)region->start().address();
+
+ xbt_assert(region->contain(simgrid::mc::remote(addr)), "Trying to read out of the region boundary.");
+
+ switch (region->storage_type()) {
+ case simgrid::mc::StorageType::Flat:
+ return (char*)region->flat_data().get() + offset;
+
+ case simgrid::mc::StorageType::Chunked: {
+ // Last byte of the region:
+ void* end = (char*)addr + size - 1;
+ if (simgrid::mc::mmu::sameChunk((std::uintptr_t)addr, (std::uintptr_t)end)) {
+ // The memory is contained in a single page:
+ return mc_translate_address_region_chunked((uintptr_t)addr, region);
+ }
+ // Otherwise, the memory spans several pages:
+ return MC_region_read_fragmented(region, target, addr, size);
+ }
+
+ default:
+ // includes StorageType::NoData and StorageType::Privatized (we currently do not pass the process_index to this
+ // function so we assume that the privatized region has been resolved in the callers)
+ xbt_die("Storage type not supported");
+ }
+}
+
+static XBT_ALWAYS_INLINE void* MC_region_read_pointer(mc_mem_region_t region, const void* addr)
+{
+ void* res;
+ return *(void**)MC_region_read(region, &res, addr, sizeof(void*));
+}
+
+#endif
--- /dev/null
+/****************************************************
+TODO: comment
+****************************************************/
+#define BOOST_TEST_MODULE pageStore
+#define BOOST_TEST_DYN_LINK
+#include <boost/test/unit_test.hpp>
+
+// /*******************************/
+// /* GENERATED FILE, DO NOT EDIT */
+// /*******************************/
+//
+// #include <stdio.h>
+// #include "xbt.h"
+// /*******************************/
+// /* GENERATED FILE, DO NOT EDIT */
+// /*******************************/
+//
+// #line 191 "mc/PageStore.cpp"
+
+#include <iostream>
+#include <cstring>
+#include <cstdint>
+
+#include <unistd.h>
+#include <sys/mman.h>
+
+#include <memory>
+
+#include "/home/onesphore/simgrid/src/mc/PageStore.hpp"
+
+static int value = 0;
+
+static void new_content(void* data, std::size_t size)
+{
+ ::memset(data, ++value, size);
+}
+
+static void* getpage()
+{
+ return mmap(nullptr, getpagesize(), PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+}
+
+BOOST_AUTO_TEST_CASE(pageStore) {
+// XBT_TEST_UNIT("base", test_mc_page_store, "Test adding/removing pages in the store")
+// {
+
+ using simgrid::mc::PageStore;
+
+ std::cout << "Test adding/removing pages in the store" << std::endl;
+
+ // xbt_test_add("Init");
+ std::size_t pagesize = (size_t) getpagesize();
+ std::unique_ptr<PageStore> store = std::unique_ptr<PageStore>(new simgrid::mc::PageStore(500));
+ void* data = getpage();
+ BOOST_TEST(store->size()==0, "Bad size");
+
+ // xbt_test_add("Store the page once");
+ new_content(data, pagesize);
+ size_t pageno1 = store->store_page(data);
+ BOOST_TEST(store->get_ref(pageno1)==1, "Bad refcount");
+ const void* copy = store->get_page(pageno1);
+ BOOST_TEST(::memcmp(data, copy, pagesize)==0, "Page data should be the same");
+ BOOST_TEST(store->size()==1, "Bad size");
+
+ // xbt_test_add("Store the same page again");
+ size_t pageno2 = store->store_page(data);
+ BOOST_TEST(pageno1==pageno2, "Page should be the same");
+ BOOST_TEST(store->get_ref(pageno1)==2, "Bad refcount");
+ BOOST_TEST(store->size()==1, "Bad size");
+
+ // xbt_test_add("Store a new page");
+ new_content(data, pagesize);
+ size_t pageno3 = store->store_page(data);
+ BOOST_TEST(pageno1 != pageno3, "New page should be different");
+ BOOST_TEST(store->size()==2, "Bad size");
+
+ // xbt_test_add("Unref pages");
+ store->unref_page(pageno1);
+ BOOST_TEST(store->get_ref(pageno1)==1, "Bad refcount");
+ BOOST_TEST(store->size()==2, "Bad size");
+ store->unref_page(pageno2);
+ BOOST_TEST(store->size()==1, "Bad size");
+
+ // xbt_test_add("Reallocate page");
+ new_content(data, pagesize);
+ size_t pageno4 = store->store_page(data);
+ BOOST_TEST(pageno1 == pageno4, "Page was not reused");
+ BOOST_TEST(store->get_ref(pageno4)==1, "Bad refcount");
+ BOOST_TEST(store->size()==2, "Bad size");
+}
+
+/*******************************/
+/* GENERATED FILE, DO NOT EDIT */
+/*******************************/
+
--- /dev/null
+/*************************************************
+TODO: comment
+*************************************************/
+#define BOOST_TEST_MODULE snapshots
+#define BOOST_TEST_DYN_LINK
+#include <boost/test/unit_test.hpp>
+
+// /*******************************/
+// /* GENERATED FILE, DO NOT EDIT */
+// /*******************************/
+//
+// #include <stdio.h>
+// #include "xbt.h"
+// /*******************************/
+// /* GENERATED FILE, DO NOT EDIT */
+// /*******************************/
+//
+// #line 180 "mc/mc_snapshot.cpp"
+
+#include <cstdlib>
+#include <cstring>
+
+#include <sys/mman.h>
+
+#include "simgrid/src/mc/mc_config.hpp"
+#include "simgrid/src/mc/mc_mmu.hpp"
+#include "simgrid/src/mc/mc_private.hpp"
+#include "simgrid/src/mc/mc_snapshot.hpp"
+
+
+static inline void init_memory(void* mem, size_t size)
+{
+ char* dest = (char*) mem;
+ for (size_t i = 0; i < size; ++i) {
+ dest[i] = rand() & 255;
+ }
+}
+
+static int test_snapshot(bool sparse_checkpoint);
+
+BOOST_AUTO_TEST_SUITE(Snapshots)
+BOOST_AUTO_TEST_CASE(flat_snapshots) {
+ BOOST_TEST(test_snapshot(0) == 1);
+}
+BOOST_AUTO_TEST_CASE(page_snapshots) {
+ BOOST_TEST(test_snapshot(1) == 1);
+}
+BOOST_AUTO_TEST_SUITE_END()
+
+static int test_snapshot(bool sparse_checkpoint) {
+
+ // xbt_test_add("Initialization");
+ _sg_mc_sparse_checkpoint = sparse_checkpoint;
+ BOOST_TEST(xbt_pagesize == getpagesize());
+ BOOST_TEST(1 << xbt_pagebits == xbt_pagesize);
+
+ std::unique_ptr<simgrid::mc::RemoteClient> process(new simgrid::mc::RemoteClient(getpid(), -1));
+ process->init();
+ mc_model_checker = new ::simgrid::mc::ModelChecker(std::move(process));
+
+ for(int n=1; n!=256; ++n) {
+
+ // Store region page(s):
+ size_t byte_size = n * xbt_pagesize;
+ void* source = mmap(nullptr, byte_size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+ BOOST_TEST(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);
+ 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);
+
+ void* destination = mmap(nullptr, byte_size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+ BOOST_TEST(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);
+ BOOST_TEST(not 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);
+ BOOST_TEST(not memcmp((char*)source + offset, read, size), "Mismatch in MC_region_read()");
+ }
+
+ // xbt_test_add("Compare whole region data for %i page(s)", n);
+
+ BOOST_TEST(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);
+ BOOST_TEST(
+ not 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);
+ BOOST_TEST(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 = nullptr;
+
+ return 1; // dummy value, for BOOST unit test
+}
+
+/*******************************/
+/* GENERATED FILE, DO NOT EDIT */
+/*******************************/
+
APPEND PROPERTY
INCLUDE_DIRECTORIES "${INTERNAL_INCLUDES}"
)
+ add_executable (unit_snapshot src/mc/snapshot/unitTest/mc_snapshot_unit_BOOST.cpp)
+ # add_library(boost_unit_test_framework SHARED IMPORTED)
+ # set_target_properties(boost_unit_test_framework PROPERTIES IMPORTED_LOCATION ${Boost_UNIT_TEST_FRAMEWORK_LIBRARY})
+ target_link_libraries(unit_snapshot simgrid boost_unit_test_framework)
+ ADD_TEST(unit_snapshot ${CMAKE_BINARY_DIR}/unit_tmgr --build_info=yes)
+ set_property(
+ TARGET unit_snapshot
+ APPEND PROPERTY
+ INCLUDE_DIRECTORIES "${INTERNAL_INCLUDES}"
+ )
else()
