[mc] Move code in simgrid::mc

[simgrid.git] / src / mc / RegionSnapshot.cpp

diff --git a/src/mc/RegionSnapshot.cpp b/src/mc/RegionSnapshot.cpp
index a045b2f..0c80a3b 100644 (file)
--- a/src/mc/RegionSnapshot.cpp
+++ b/src/mc/RegionSnapshot.cpp
@@ -39,14 +39,14 @@ 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_ = ::malloc(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;
@@ -59,7 +59,7 @@ 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:
@@ -81,16 +81,14 @@ 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 madvise bits of the heap;
+  // * 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),
@@ -98,7 +96,7 @@ RegionSnapshot dense_region(
 
   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);
 
   simgrid::mc::RegionSnapshot region(
@@ -121,11 +119,10 @@ RegionSnapshot region(
   RegionType type, void *start_addr, void* permanent_addr, size_t size,
   RegionSnapshot const* ref_region)
 {
-  if (_sg_mc_sparse_checkpoint) {
+  if (_sg_mc_sparse_checkpoint)
     return sparse_region(type, start_addr, permanent_addr, size, ref_region);
-  } else  {
+  else
     return dense_region(type, start_addr, permanent_addr, size);
-  }
 }
 
 RegionSnapshot sparse_region(RegionType region_type,
@@ -143,14 +140,14 @@ RegionSnapshot sparse_region(RegionType region_type,
     "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);
+  size_t page_count = simgrid::mc::mmu::chunkCount(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);
+      simgrid::mc::mmu::split((std::size_t) permanent_addr).first, page_count);
     ref_page_numbers = ref_region->page_data().pagenos();
   }