/* MC interface: definitions that non-MC modules must see, but not the user */
-/* Copyright (c) 2014-2015. The SimGrid Team. All rights reserved. */
+/* Copyright (c) 2014-2015. 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 <xbt/mmalloc.h>
-extern "C" {
+#define SOFT_DIRTY_BIT_NUMBER 55
+#define SOFT_DIRTY (((uint64_t)1) << SOFT_DIRTY_BIT_NUMBER)
+
+using simgrid::mc::remote;
-// ***** Region management:
+namespace simgrid {
+namespace mc {
/** @brief Take a per-page snapshot of a region
*
* @param pag_count Number of pages of the region
* @return Snapshot page numbers of this new snapshot
*/
-size_t* mc_take_page_snapshot_region(mc_process_t process,
- void* data, size_t page_count)
+PerPageCopy::PerPageCopy(PageStore& store, AddressSpace& as,
+ remote_ptr<void> addr, std::size_t page_count,
+ const size_t* ref_page_numbers, const std::uint64_t* pagemap)
{
- size_t* pagenos = (size_t*) malloc(page_count * sizeof(size_t));
+ store_ = &store;
+ this->pagenos_.resize(page_count);
+ std::vector<char> buffer(xbt_pagesize);
- const bool is_self = MC_process_is_self(process);
+ for (size_t i = 0; i != page_count; ++i) {
- void* temp = NULL;
- if (!is_self)
- temp = malloc(xbt_pagesize);
+ // We don't have to compare soft-clean pages:
+ if (ref_page_numbers && pagemap && !(pagemap[i] & SOFT_DIRTY)) {
+ pagenos_[i] = ref_page_numbers[i];
+ store_->ref_page(ref_page_numbers[i]);
+ continue;
+ }
- for (size_t i=0; i!=page_count; ++i) {
+ remote_ptr<void> page = remote(addr.address() + (i << xbt_pagebits));
+ xbt_assert(mc_page_offset((void*)page.address())==0,
+ "Not at the beginning of a page");
- // Otherwise, we need to store the page the hard way
- // (by reading its content):
- void* page = (char*) data + (i << xbt_pagebits);
- xbt_assert(mc_page_offset(page)==0, "Not at the beginning of a page");
- void* page_data;
- if (is_self) {
- page_data = page;
- } else {
/* 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:
- let the application snapshot itself;
- move the segments in shared memory (this will break `fork` however).
*/
- page_data = temp;
- process->read_bytes(
- temp, xbt_pagesize, (std::uint64_t) page,
+
+ as.read_bytes(
+ buffer.data(), xbt_pagesize, page,
simgrid::mc::ProcessIndexDisabled);
- }
- pagenos[i] = mc_model_checker->page_store().store_page(page_data);
- }
+ pagenos_[i] = store_->store_page(buffer.data());
- free(temp);
- return pagenos;
+ }
}
-void mc_free_page_snapshot_region(size_t* pagenos, size_t page_count)
-{
- for (size_t i=0; i!=page_count; ++i) {
- mc_model_checker->page_store().unref_page(pagenos[i]);
- }
}
+}
+
+extern "C" {
/** @brief Restore a snapshot of a region
*
* @param page_count Number of pages of the region
* @param pagenos
*/
-void mc_restore_page_snapshot_region(mc_process_t process,
- void* start_addr, size_t page_count, size_t* pagenos)
+void mc_restore_page_snapshot_region(simgrid::mc::Process* process,
+ void* start_addr, simgrid::mc::PerPageCopy const& pages_copy)
{
- for (size_t i=0; i!=page_count; ++i) {
+ for (size_t i = 0; i != pages_copy.page_count(); ++i) {
// Otherwise, copy the page:
void* target_page = mc_page_from_number(start_addr, i);
- const void* source_page = mc_model_checker->page_store().get_page(pagenos[i]);
- MC_process_write(process, source_page, target_page, xbt_pagesize);
+ const void* source_page = pages_copy.page(i);
+ process->write_bytes(source_page, xbt_pagesize, remote(target_page));
}
}
// ***** High level API
-mc_mem_region_t mc_region_new_sparse(mc_region_type_t region_type,
- void *start_addr, void* permanent_addr, size_t size)
+void mc_region_restore_sparse(simgrid::mc::Process* process, mc_mem_region_t reg)
{
- mc_process_t process = &mc_model_checker->process();
-
- mc_mem_region_t region = xbt_new(s_mc_mem_region_t, 1);
- region->region_type = region_type;
- region->storage_type = MC_REGION_STORAGE_TYPE_CHUNKED;
- region->start_addr = start_addr;
- region->permanent_addr = permanent_addr;
- region->size = size;
-
- 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);
-
- // Take incremental snapshot:
- region->chunked.page_numbers = mc_take_page_snapshot_region(process,
- permanent_addr, page_count);
-
- return region;
-}
-
-void mc_region_restore_sparse(mc_process_t process, mc_mem_region_t reg)
-{
- xbt_assert((((uintptr_t)reg->permanent_addr) & (xbt_pagesize-1)) == 0,
+ xbt_assert(((reg->permanent_address().address()) & (xbt_pagesize-1)) == 0,
"Not at the beginning of a page");
- size_t page_count = mc_page_count(reg->size);
-
+ xbt_assert(mc_page_count(reg->size()) == reg->page_data().page_count());
mc_restore_page_snapshot_region(process,
- reg->permanent_addr, page_count, reg->chunked.page_numbers);
+ (void*) reg->permanent_address().address(), reg->page_data());
}
}
