X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/136ba04f94e60909c0dde0b12252e86a2b2197e0..b17531686acca9a61c349274d9de9c0dc4c7e07a:/src/mc/RegionSnapshot.cpp diff --git a/src/mc/RegionSnapshot.cpp b/src/mc/RegionSnapshot.cpp index 8bf91df19e..333aed2ed3 100644 --- a/src/mc/RegionSnapshot.cpp +++ b/src/mc/RegionSnapshot.cpp @@ -43,10 +43,10 @@ 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; @@ -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,