X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/f28ba1d843aca0db6f81612db8fc099f2c0021e2..e3f5ca3fd3726e67046afbd03e48e9cd7294b835:/src/mc/mc_snapshot.c

diff --git a/src/mc/mc_snapshot.c b/src/mc/mc_snapshot.c
index 20d7642d1c..5746848cd4 100644
--- a/src/mc/mc_snapshot.c
+++ b/src/mc/mc_snapshot.c
@@ -4,59 +4,51 @@
 /* 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 <stdbool.h>
+
+#include "internal_config.h"
+#include "smpi/private.h"
+
+#include "mc_snapshot.h"
 #include "mc_private.h"
 #include "mc_mmu.h"
+#include "mc_page_store.h"
 
-mc_mem_region_t mc_get_snapshot_region(void* addr, mc_snapshot_t snapshot)
+/** @brief Find the snapshoted region from a pointer
+ *
+ *  @param addr     Pointer
+ *  @param snapshot Snapshot
+ *  @param Snapshot region in the snapshot this pointer belongs to
+ *         (or NULL if it does not belong to any snapshot region)
+ * */
+mc_mem_region_t mc_get_snapshot_region(void* addr, mc_snapshot_t snapshot, int process_index)
 {
-  for (size_t i = 0; i != NB_REGIONS; ++i) {
-    mc_mem_region_t region = snapshot->regions[i];
-    void* start = region->start_addr;
-    void* end = (char*) start + region->size;
+  size_t n = snapshot->snapshot_regions_count;
+  for (size_t i = 0; i != n; ++i) {
+    mc_mem_region_t region = snapshot->snapshot_regions[i];
+    if (!(region && mc_region_contain(region, addr)))
+      continue;
 
-    if (addr >= start && addr < end) {
-      return region;
+    if (region->storage_type == MC_REGION_STORAGE_TYPE_PRIVATIZED) {
+#ifdef HAVE_SMPI
+      if (process_index < 0) {
+        xbt_die("Missing process index");
+      }
+      if (process_index >= region->privatized.regions_count) {
+        xbt_die("Invalid process index");
+      }
+      mc_mem_region_t priv_region = region->privatized.regions[process_index];
+      xbt_assert(mc_region_contain(priv_region, addr));
+      return priv_region;
+#else
+      xbt_die("Privatized region in a non SMPI build (this should not happen)");
+#endif
     }
-  }
-
-  return NULL;
-}
-
-void* mc_translate_address_region(uintptr_t addr, mc_mem_region_t region)
-{
-  if (!region) {
-    return (void *) addr;
-  }
-
-  // Flat snapshot:
-  else if (region->data) {
-    uintptr_t offset = addr - (uintptr_t) region->start_addr;
-    return (void *) ((uintptr_t) region->data + offset);
-  }
 
-  // Per-page snapshot:
-  else if (region->page_numbers) {
-    size_t pageno = mc_page_number(region->start_addr, (void*) addr);
-    size_t snapshot_pageno = region->page_numbers[pageno];
-    const void* snapshot_page = mc_page_store_get_page(mc_model_checker->pages, snapshot_pageno);
-    return (char*) snapshot_page + mc_page_offset((void*) addr);
+    return region;
   }
 
-  else {
-    xbt_die("No data for this memory region");
-  }
-}
-
-void* mc_translate_address(uintptr_t addr, mc_snapshot_t snapshot)
-{
-
-  // If not in a process state/clone:
-  if (!snapshot) {
-    return (uintptr_t *) addr;
-  }
-
-  mc_mem_region_t region = mc_get_snapshot_region((void*) addr, snapshot);
-  return mc_translate_address_region(addr, region);
+  return NULL;
 }
 
 /** @brief Read memory from a snapshot region broken across fragmented pages
@@ -67,93 +59,224 @@ void* mc_translate_address(uintptr_t addr, mc_snapshot_t snapshot)
  *  @param size    Size of the data to read in bytes
  *  @return Pointer where the data is located (target buffer of original location)
  */
-static void* mc_snapshot_read_fragmented(void* addr, mc_mem_region_t region, void* target, size_t size)
+void* mc_snapshot_read_fragmented(void* addr, mc_mem_region_t region, void* target, size_t size)
 {
+  // Last byte of the memory area:
   void* end = (char*) addr + size - 1;
+
+  // Page of the last byte of the memory area:
   size_t page_end = mc_page_number(NULL, end);
 
+  void* dest = target;
+
+  if (dest==NULL) {
+    xbt_die("Missing destination buffer for fragmented memory access");
+  }
+
   // Read each page:
   while (mc_page_number(NULL, addr) != page_end) {
     void* snapshot_addr = mc_translate_address_region((uintptr_t) addr, region);
     void* next_page = mc_page_from_number(NULL, mc_page_number(NULL, addr) + 1);
     size_t readable = (char*) next_page - (char*) addr;
-    memcpy(target, snapshot_addr, readable);
+    memcpy(dest, snapshot_addr, readable);
     addr = (char*) addr + readable;
-    target = (char*) target + readable;
+    dest = (char*) dest + readable;
     size -= readable;
   }
 
   // Read the end:
   void* snapshot_addr = mc_translate_address_region((uintptr_t)addr, region);
-  memcpy(target, snapshot_addr, size);
+  memcpy(dest, snapshot_addr, size);
 
   return target;
 }
 
-/** @brief Read memory from a snapshot region
- *
- *  @param addr    Process (non-snapshot) address of the data
- *  @param region  Snapshot memory region where the data is located
- *  @param target  Buffer to store the value
- *  @param size    Size of the data to read in bytes
- *  @return Pointer where the data is located (target buffer of original location)
- */
-void* mc_snapshot_read_region(void* addr, mc_mem_region_t region, void* target, size_t size)
-{
-  uintptr_t offset = (uintptr_t) addr - (uintptr_t) region->start_addr;
-
-  if (addr < region->start_addr || (char*) addr+size >= (char*)region->start_addr+region->size) {
-    xbt_die("Trying to read out of the region boundary.");
-  }
-
-  // Linear memory region:
-  if (region->data) {
-    return (void*) ((uintptr_t) region->data + offset);
-  }
-
-  // Fragmented memory region:
-  else if (region->page_numbers) {
-    void* end = (char*) addr + size - 1;
-    if( mc_same_page(addr, end) ) {
-      // The memory is contained in a single page:
-      return mc_translate_address_region((uintptr_t) addr, region);
-    } else {
-      // The memory spans several pages:
-      return mc_snapshot_read_fragmented(addr, region, target, size);
-    }
-  }
-
-  else {
-    xbt_die("No data available for this region");
-  }
-}
-
 /** @brief Read memory from a snapshot
  *
  *  @param addr     Process (non-snapshot) address of the data
  *  @param snapshot Snapshot (or NULL is no snapshot)
  *  @param target   Buffer to store the value
  *  @param size     Size of the data to read in bytes
- *  @return Pointer where the data is located (target buffer of original location)
+ *  @return Pointer where the data is located (target buffer or original location)
  */
-void* mc_snapshot_read(void* addr, mc_snapshot_t snapshot, void* target, size_t size)
+void* mc_snapshot_read(void* addr, mc_snapshot_t snapshot, int process_index, void* target, size_t size)
 {
   if (snapshot) {
-    mc_mem_region_t region = mc_get_snapshot_region(addr, snapshot);
+    mc_mem_region_t region = mc_get_snapshot_region(addr, snapshot, process_index);
     return mc_snapshot_read_region(addr, region, target, size);
   } else {
     return addr;
   }
 }
 
-int mc_snapshot_memcp(
-  void* addr1, mc_snapshot_t snapshot1,
-  void* addr2, mc_snapshot_t snapshot2, size_t size)
+/** Compare memory between snapshots (with known regions)
+ *
+ * @param addr1 Address in the first snapshot
+ * @param snapshot2 Region of the address in the first snapshot
+ * @param addr2 Address in the second snapshot
+ * @param snapshot2 Region of the address in the second snapshot
+ * @return same as memcmp
+ * */
+int mc_snapshot_region_memcmp(
+  void* addr1, mc_mem_region_t region1,
+  void* addr2, mc_mem_region_t region2,
+  size_t size)
 {
-  void* buffer1 = mc_snapshot_read(addr1, snapshot1, alloca(size), size);
-  void* buffer2 = mc_snapshot_read(addr2, snapshot2, alloca(size), size);
+  // Using alloca() for large allocations may trigger stack overflow:
+  // use malloc if the buffer is too big.
+  bool stack_alloc = size < 64;
+  const bool region1_need_buffer = region1==NULL || region1->storage_type==MC_REGION_STORAGE_TYPE_FLAT;
+  const bool region2_need_buffer = region2==NULL || region2->storage_type==MC_REGION_STORAGE_TYPE_FLAT;
+  void* buffer1a = region1_need_buffer ? NULL : stack_alloc ? alloca(size) : malloc(size);
+  void* buffer2a = region2_need_buffer ? NULL : stack_alloc ? alloca(size) : malloc(size);
+  void* buffer1 = mc_snapshot_read_region(addr1, region1, buffer1a, size);
+  void* buffer2 = mc_snapshot_read_region(addr2, region2, buffer2a, size);
+  int res;
   if (buffer1 == buffer2) {
-    return 0;
+    res = 0;
+  } else {
+    res = memcmp(buffer1, buffer2, size);
   }
-  return memcmp(buffer1, buffer2, size);
+  if (!stack_alloc) {
+    free(buffer1a);
+    free(buffer2a);
+  }
+  return res;
+}
+
+/** Compare memory between snapshots
+ *
+ * @param addr1 Address in the first snapshot
+ * @param snapshot1 First snapshot
+ * @param addr2 Address in the second snapshot
+ * @param snapshot2 Second snapshot
+ * @return same as memcmp
+ * */
+int mc_snapshot_memcmp(
+  void* addr1, mc_snapshot_t snapshot1,
+  void* addr2, mc_snapshot_t snapshot2, int process_index, size_t size)
+{
+  mc_mem_region_t region1 = mc_get_snapshot_region(addr1, snapshot1, process_index);
+  mc_mem_region_t region2 = mc_get_snapshot_region(addr2, snapshot2, process_index);
+  return mc_snapshot_region_memcmp(addr1, region1, addr2, region2, size);
+}
+
+#ifdef SIMGRID_TEST
+
+#include <string.h>
+#include <stdlib.h>
+
+#include <sys/mman.h>
+
+#include "mc/mc_private.h"
+#include "mc/mc_snapshot.h"
+#include "mc/mc_mmu.h"
+
+XBT_TEST_SUITE("mc_snapshot", "Snapshots");
+
+static inline void init_memory(void* mem, size_t size)
+{
+  char* dest = (char*) mem;
+  for (int i=0; i!=size; ++i) {
+    dest[i] = rand() & 255;
+  }
+}
+
+static void test_snapshot(bool sparse_checkpoint);
+
+XBT_TEST_UNIT("page_snapshots", test_per_snpashots, "Test per-page snapshots")
+{
+  test_snapshot(1);
+}
+
+
+XBT_TEST_UNIT("flat_snapshot", test_flat_snapshots, "Test flat snapshots")
+{
+  test_snapshot(0);
 }
+
+
+static void test_snapshot(bool sparse_checkpoint) {
+
+  xbt_test_add("Initialisation");
+  _sg_mc_soft_dirty = 0;
+  _sg_mc_sparse_checkpoint = sparse_checkpoint;
+  xbt_assert(xbt_pagesize == getpagesize());
+  xbt_assert(1 << xbt_pagebits == xbt_pagesize);
+  mc_model_checker = xbt_new0(s_mc_model_checker_t, 1);
+  mc_model_checker->pages = mc_pages_store_new();
+
+  for(int n=1; n!=256; ++n) {
+
+    // Store region page(s):
+    size_t byte_size = n * xbt_pagesize;
+    void* source = mmap(NULL, byte_size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+    xbt_assert(source!=MAP_FAILED, "Could not allocate source memory");
+
+    // Init memory and take snapshots:
+    init_memory(source, byte_size);
+    mc_mem_region_t region0 = mc_region_new_sparse(MC_REGION_TYPE_UNKNOWN, source, source, byte_size, NULL);
+    for(int i=0; i<n; i+=2) {
+      init_memory((char*) source + i*xbt_pagesize, xbt_pagesize);
+    }
+    mc_mem_region_t region = mc_region_new_sparse(MC_REGION_TYPE_UNKNOWN, source, source, byte_size, NULL);
+
+    void* destination = mmap(NULL, byte_size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+    xbt_assert(source!=MAP_FAILED, "Could not allocate destination memory");
+
+    xbt_test_add("Reading whole region data for %i page(s)", n);
+    void* read = mc_snapshot_read_region(source, region, destination, byte_size);
+    xbt_test_assert(!memcmp(source, read, byte_size), "Mismatch in mc_snapshot_read_region()");
+
+    xbt_test_add("Reading parts of region data for %i page(s)", n);
+    for(int j=0; j!=100; ++j) {
+      size_t offset = rand() % byte_size;
+      size_t size = rand() % (byte_size - offset);
+      void* read = mc_snapshot_read_region((char*) source+offset, region, destination, size);
+      xbt_test_assert(!memcmp((char*) source+offset, read, size),
+        "Mismatch in mc_snapshot_read_region()");
+    }
+
+    xbt_test_add("Compare whole region data for %i page(s)", n);
+    xbt_test_assert(!mc_snapshot_region_memcmp(source, NULL, source, region, byte_size),
+      "Mismatch in mc_snapshot_region_memcmp() for the whole region");
+    xbt_test_assert(mc_snapshot_region_memcmp(source, region0, source, region, byte_size),
+      "Unexpected match in mc_snapshot_region_memcmp() with previous snapshot");
+
+    xbt_test_add("Compare parts of region data for %i page(s) with current value", n);
+    for(int j=0; j!=100; ++j) {
+      size_t offset = rand() % byte_size;
+      size_t size = rand() % (byte_size - offset);
+      xbt_test_assert(!mc_snapshot_region_memcmp((char*) source+offset, NULL, (char*) source+offset, region, size),
+        "Mismatch in mc_snapshot_region_memcmp()");
+    }
+
+    xbt_test_add("Compare parts of region data for %i page(s) with itself", n);
+    for(int j=0; j!=100; ++j) {
+      size_t offset = rand() % byte_size;
+      size_t size = rand() % (byte_size - offset);
+      xbt_test_assert(!mc_snapshot_region_memcmp((char*) source+offset, region, (char*) source+offset, region, size),
+        "Mismatch in mc_snapshot_region_memcmp()");
+    }
+
+    if (n==1) {
+      xbt_test_add("Read pointer for %i page(s)", n);
+      memcpy(source, &mc_model_checker, sizeof(void*));
+      mc_mem_region_t region2 = mc_region_new_sparse(MC_REGION_TYPE_UNKNOWN, source, source, byte_size, NULL);
+      xbt_test_assert(mc_snapshot_read_pointer_region(source, region2) == mc_model_checker,
+        "Mismtach in mc_snapshot_read_pointer_region()");
+      MC_region_destroy(region2);
+    }
+
+    MC_region_destroy(region);
+    MC_region_destroy(region0);
+    munmap(destination, byte_size);
+    munmap(source, byte_size);
+  }
+
+  mc_pages_store_delete(mc_model_checker->pages);
+  xbt_free(mc_model_checker);
+  mc_model_checker = NULL;
+}
+
+#endif /* SIMGRID_TEST */