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-rw-r--r--malloc/hooks.c150
1 files changed, 50 insertions, 100 deletions
diff --git a/malloc/hooks.c b/malloc/hooks.c
index 0d2bb96c03..45241f2170 100644
--- a/malloc/hooks.c
+++ b/malloc/hooks.c
@@ -548,11 +548,7 @@ int
 __malloc_set_state (void *msptr)
 {
   struct malloc_save_state *ms = (struct malloc_save_state *) msptr;
-  size_t i;
-  mbinptr b;
 
-  disallow_malloc_check = 1;
-  ptmalloc_init ();
   if (ms->magic != MALLOC_STATE_MAGIC)
     return -1;
 
@@ -560,106 +556,60 @@ __malloc_set_state (void *msptr)
   if ((ms->version & ~0xffl) > (MALLOC_STATE_VERSION & ~0xffl))
     return -2;
 
-  (void) mutex_lock (&main_arena.mutex);
-  /* There are no fastchunks.  */
-  clear_fastchunks (&main_arena);
-  if (ms->version >= 4)
-    set_max_fast (ms->max_fast);
-  else
-    set_max_fast (64);  /* 64 used to be the value we always used.  */
-  for (i = 0; i < NFASTBINS; ++i)
-    fastbin (&main_arena, i) = 0;
-  for (i = 0; i < BINMAPSIZE; ++i)
-    main_arena.binmap[i] = 0;
-  top (&main_arena) = ms->av[2];
-  main_arena.last_remainder = 0;
-  for (i = 1; i < NBINS; i++)
-    {
-      b = bin_at (&main_arena, i);
-      if (ms->av[2 * i + 2] == 0)
-        {
-          assert (ms->av[2 * i + 3] == 0);
-          first (b) = last (b) = b;
-        }
+  /* We do not need to perform locking here because __malloc_set_state
+     must be called before the first call into the malloc subsytem
+     (usually via __malloc_initialize_hook).  pthread_create always
+     calls calloc and thus must be called only afterwards, so there
+     cannot be more than one thread when we reach this point.  */
+
+  /* Disable the malloc hooks (and malloc checking).  */
+  __malloc_hook = NULL;
+  __realloc_hook = NULL;
+  __free_hook = NULL;
+  __memalign_hook = NULL;
+  using_malloc_checking = 0;
+
+  /* Patch the dumped heap.  We no longer try to integrate into the
+     existing heap.  Instead, we mark the existing chunks as mmapped.
+     Together with the update to dumped_main_arena_start and
+     dumped_main_arena_end, realloc and free will recognize these
+     chunks as dumped fake mmapped chunks and never free them.  */
+
+  /* Find the chunk with the lowest address with the heap.  */
+  mchunkptr chunk = NULL;
+  {
+    size_t *candidate = (size_t *) ms->sbrk_base;
+    size_t *end = (size_t *) (ms->sbrk_base + ms->sbrked_mem_bytes);
+    while (candidate < end)
+      if (*candidate != 0)
+	{
+	  chunk = mem2chunk ((void *) (candidate + 1));
+	  break;
+	}
       else
-        {
-          if (ms->version >= 3 &&
-              (i < NSMALLBINS || (largebin_index (chunksize (ms->av[2 * i + 2])) == i &&
-                                  largebin_index (chunksize (ms->av[2 * i + 3])) == i)))
-            {
-              first (b) = ms->av[2 * i + 2];
-              last (b) = ms->av[2 * i + 3];
-              /* Make sure the links to the bins within the heap are correct.  */
-              first (b)->bk = b;
-              last (b)->fd = b;
-              /* Set bit in binblocks.  */
-              mark_bin (&main_arena, i);
-            }
-          else
-            {
-              /* Oops, index computation from chunksize must have changed.
-                 Link the whole list into unsorted_chunks.  */
-              first (b) = last (b) = b;
-              b = unsorted_chunks (&main_arena);
-              ms->av[2 * i + 2]->bk = b;
-              ms->av[2 * i + 3]->fd = b->fd;
-              b->fd->bk = ms->av[2 * i + 3];
-              b->fd = ms->av[2 * i + 2];
-            }
-        }
-    }
-  if (ms->version < 3)
-    {
-      /* Clear fd_nextsize and bk_nextsize fields.  */
-      b = unsorted_chunks (&main_arena)->fd;
-      while (b != unsorted_chunks (&main_arena))
-        {
-          if (!in_smallbin_range (chunksize (b)))
-            {
-              b->fd_nextsize = NULL;
-              b->bk_nextsize = NULL;
-            }
-          b = b->fd;
-        }
-    }
-  mp_.sbrk_base = ms->sbrk_base;
-  main_arena.system_mem = ms->sbrked_mem_bytes;
-  mp_.trim_threshold = ms->trim_threshold;
-  mp_.top_pad = ms->top_pad;
-  mp_.n_mmaps_max = ms->n_mmaps_max;
-  mp_.mmap_threshold = ms->mmap_threshold;
-  check_action = ms->check_action;
-  main_arena.max_system_mem = ms->max_sbrked_mem;
-  mp_.n_mmaps = ms->n_mmaps;
-  mp_.max_n_mmaps = ms->max_n_mmaps;
-  mp_.mmapped_mem = ms->mmapped_mem;
-  mp_.max_mmapped_mem = ms->max_mmapped_mem;
-  /* add version-dependent code here */
-  if (ms->version >= 1)
-    {
-      /* Check whether it is safe to enable malloc checking, or whether
-         it is necessary to disable it.  */
-      if (ms->using_malloc_checking && !using_malloc_checking &&
-          !disallow_malloc_check)
-        __malloc_check_init ();
-      else if (!ms->using_malloc_checking && using_malloc_checking)
-        {
-          __malloc_hook = NULL;
-          __free_hook = NULL;
-          __realloc_hook = NULL;
-          __memalign_hook = NULL;
-          using_malloc_checking = 0;
-        }
-    }
-  if (ms->version >= 4)
+	++candidate;
+  }
+  if (chunk == NULL)
+    return 0;
+
+  /* Iterate over the dumped heap and patch the chunks so that they
+     are treated as fake mmapped chunks.  */
+  mchunkptr top = ms->av[2];
+  while (chunk < top)
     {
-      mp_.arena_test = ms->arena_test;
-      mp_.arena_max = ms->arena_max;
-      narenas = ms->narenas;
+      if (inuse (chunk))
+	{
+	  /* Mark chunk as mmapped, to trigger the fallback path.  */
+	  size_t size = chunksize (chunk);
+	  set_head (chunk, size | IS_MMAPPED);
+	}
+      chunk = next_chunk (chunk);
     }
-  check_malloc_state (&main_arena);
 
-  (void) mutex_unlock (&main_arena.mutex);
+  /* The dumped fake mmapped chunks all lie in this address range.  */
+  dumped_main_arena_start = (mchunkptr) ms->sbrk_base;
+  dumped_main_arena_end = top;
+
   return 0;
 }