X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/9ae3c710a6a8ac04570f77d88eb8e0c7a13f101c..4b0aa1525597fd0800c4d00c6df3f3c49d53ee2c:/src/mc/sosp/ChunkedData.cpp

diff --git a/src/mc/sosp/ChunkedData.cpp b/src/mc/sosp/ChunkedData.cpp
new file mode 100644
index 0000000000..fcf51797b1
--- /dev/null
+++ b/src/mc/sosp/ChunkedData.cpp
@@ -0,0 +1,53 @@
+/* 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/sosp/ChunkedData.hpp"
+#include "src/mc/sosp/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());
+  }
+}
+
+} // namespace mc
+} // namespace simgrid