X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/53b9ff1b6972dffeabd543a09c89170663c30ad1..c9e3badfcca0d44e112171cefd237ed3f0ae01ca:/src/mc/RegionSnapshot.cpp

diff --git a/src/mc/RegionSnapshot.cpp b/src/mc/RegionSnapshot.cpp
index a045b2f8ec..4ebfbe1729 100644
--- a/src/mc/RegionSnapshot.cpp
+++ b/src/mc/RegionSnapshot.cpp
@@ -1,4 +1,4 @@
-/* Copyright (c) 2007-2015. The SimGrid Team.
+/* Copyright (c) 2007-2017. The SimGrid Team.
  * All rights reserved.                                                     */
 
 /* This program is free software; you can redistribute it and/or modify it
@@ -7,20 +7,19 @@
 #include <cstdlib>
 
 #include <sys/mman.h>
+#ifdef __FreeBSD__
+# define MAP_POPULATE MAP_PREFAULT_READ
+#endif
 
 #include "mc/mc.h"
-#include "src/mc/mc_snapshot.h"
+#include "src/mc/mc_snapshot.hpp"
 
 #include "src/mc/ChunkedData.hpp"
 #include "src/mc/RegionSnapshot.hpp"
 
-extern "C" {
-
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_RegionSnaphot, mc,
                                 "Logging specific to region snapshots");
 
-}
-
 namespace simgrid {
 namespace mc {
 
@@ -39,14 +38,14 @@ const char* to_cstr(RegionType region)
   }
 }
 
-buffer::buffer(std::size_t size, Type type) : size_(size), type_(type)
+Buffer::Buffer(std::size_t size, Type type) : size_(size), type_(type)
 {
   switch(type_) {
   case Type::Malloc:
-    data_ = malloc(size_);
+    data_ = ::operator new(size_);
     break;
   case Type::Mmap:
-    data_ = mmap(nullptr, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_POPULATE, -1, 0);
+    data_ = ::mmap(nullptr, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_POPULATE, -1, 0);
     if (data_ == MAP_FAILED) {
       data_ = nullptr;
       size_ = 0;
@@ -59,11 +58,11 @@ buffer::buffer(std::size_t size, Type type) : size_(size), type_(type)
   }
 }
 
-void buffer::clear() noexcept
+void Buffer::clear() noexcept
 {
   switch(type_) {
   case Type::Malloc:
-    std::free(data_);
+    ::operator delete(data_);
     break;
   case Type::Mmap:
     if (munmap(data_, size_) != 0)
@@ -81,25 +80,25 @@ RegionSnapshot dense_region(
   RegionType region_type,
   void *start_addr, void* permanent_addr, size_t size)
 {
-  simgrid::mc::buffer::Type buffer_type;
+  // 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)
-    // We use mmap to allocate the memory in order to madvise it.
-    // We don't want to madvise the main heap.
-    // Moreover we get aligned pgaes which is merge-friendly.
-    buffer_type = simgrid::mc::buffer::Type::Mmap;
+    data = Buffer::mmap(size);
   else
-    buffer_type = simgrid::mc::buffer::Type::Malloc;
-
-  simgrid::mc::buffer data(size, buffer_type);
+    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.
-    // There no point to let KSM do the hard work before that.
+    // 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);
@@ -107,7 +106,7 @@ RegionSnapshot dense_region(
 
   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 std::move(region);
+  return region;
 }
 
 /** @brief Take a snapshot of a given region
@@ -118,52 +117,34 @@ RegionSnapshot dense_region(
  * @param size         Size of the data*
  */
 RegionSnapshot region(
-  RegionType type, void *start_addr, void* permanent_addr, size_t size,
-  RegionSnapshot const* ref_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, ref_region);
-  } else  {
+  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,
-  RegionSnapshot const* ref_region)
+  void *start_addr, void* permanent_addr, size_t size)
 {
-  simgrid::mc::Process* process = &mc_model_checker->process();
+  simgrid::mc::RemoteClient* process = &mc_model_checker->process();
   assert(process != nullptr);
 
-  bool use_soft_dirty = _sg_mc_sparse_checkpoint && _sg_mc_soft_dirty
-    && ref_region != nullptr
-    && ref_region->storage_type() == simgrid::mc::StorageType::Chunked;
-
   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 = mc_page_count(size);
-
-  std::vector<std::uint64_t> pagemap;
-  const size_t* ref_page_numbers = nullptr;
-  if (use_soft_dirty) {
-    pagemap.resize(page_count);
-    process->read_pagemap(pagemap.data(),
-      mc_page_number(nullptr, permanent_addr), page_count);
-    ref_page_numbers = ref_region->page_data().pagenos();
-  }
+  size_t page_count = simgrid::mc::mmu::chunkCount(size);
 
-  simgrid::mc::ChunkedData page_data(
-    mc_model_checker->page_store(), *process, permanent_addr, page_count,
-    ref_page_numbers,
-    use_soft_dirty ? pagemap.data() : nullptr);
+  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 std::move(region);
+  return region;
 }
-  
+
 }
 }