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authorJakub Jelinek <jakub@redhat.com>2007-07-31 13:33:18 +0000
committerJakub Jelinek <jakub@redhat.com>2007-07-31 13:33:18 +0000
commit32c075e1f01849e161724bbd400ba77244e482cc (patch)
tree5f083a3f352104f32bb6c902d57fa3f294bd8d4d /malloc/arena.c
parentd6220e9ee38c1c9285221b023346201ec5f511b3 (diff)
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Diffstat (limited to 'malloc/arena.c')
-rw-r--r--malloc/arena.c45
1 files changed, 33 insertions, 12 deletions
diff --git a/malloc/arena.c b/malloc/arena.c
index 1d9f952112..0dcb7cb9f8 100644
--- a/malloc/arena.c
+++ b/malloc/arena.c
@@ -1,5 +1,6 @@
/* Malloc implementation for multiple threads without lock contention.
- Copyright (C) 2001,2002,2003,2004,2005,2006 Free Software Foundation, Inc.
+ Copyright (C) 2001,2002,2003,2004,2005,2006,2007
+ Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Wolfram Gloger <wg@malloc.de>, 2001.
@@ -59,10 +60,12 @@ typedef struct _heap_info {
mstate ar_ptr; /* Arena for this heap. */
struct _heap_info *prev; /* Previous heap. */
size_t size; /* Current size in bytes. */
+ size_t mprotect_size; /* Size in bytes that has been mprotected
+ PROT_READ|PROT_WRITE. */
/* Make sure the following data is properly aligned, particularly
that sizeof (heap_info) + 2 * SIZE_SZ is a multiple of
- MALLOG_ALIGNMENT. */
- char pad[-5 * SIZE_SZ & MALLOC_ALIGN_MASK];
+ MALLOC_ALIGNMENT. */
+ char pad[-6 * SIZE_SZ & MALLOC_ALIGN_MASK];
} heap_info;
/* Get a compile-time error if the heap_info padding is not correct
@@ -149,7 +152,7 @@ int __malloc_initialized = -1;
static __malloc_ptr_t (*save_malloc_hook) (size_t __size,
__const __malloc_ptr_t);
-# if !defined _LIBC || (defined SHARED && !USE___THREAD)
+# if !defined _LIBC || !defined USE_TLS || (defined SHARED && !USE___THREAD)
static __malloc_ptr_t (*save_memalign_hook) (size_t __align, size_t __size,
__const __malloc_ptr_t);
# endif
@@ -385,7 +388,7 @@ extern struct dl_open_hook *_dl_open_hook;
libc_hidden_proto (_dl_open_hook);
# endif
-# if defined SHARED && !USE___THREAD
+# if defined SHARED && defined USE_TLS && !USE___THREAD
/* This is called by __pthread_initialize_minimal when it needs to use
malloc to set up the TLS state. We cannot do the full work of
ptmalloc_init (below) until __pthread_initialize_minimal has finished,
@@ -428,7 +431,7 @@ ptmalloc_init (void)
__malloc_initialized = 0;
#ifdef _LIBC
-# if defined SHARED && !USE___THREAD
+# if defined SHARED && defined USE_TLS && !USE___THREAD
/* ptmalloc_init_minimal may already have been called via
__libc_malloc_pthread_startup, above. */
if (mp_.pagesize == 0)
@@ -437,7 +440,7 @@ ptmalloc_init (void)
ptmalloc_init_minimal();
#ifndef NO_THREADS
-# if defined _LIBC
+# if defined _LIBC && defined USE_TLS
/* We know __pthread_initialize_minimal has already been called,
and that is enough. */
# define NO_STARTER
@@ -692,6 +695,7 @@ new_heap(size, top_pad) size_t size, top_pad;
}
h = (heap_info *)p2;
h->size = size;
+ h->mprotect_size = size;
THREAD_STAT(stat_n_heaps++);
return h;
}
@@ -714,17 +718,34 @@ grow_heap(h, diff) heap_info *h; long diff;
new_size = (long)h->size + diff;
if((unsigned long) new_size > (unsigned long) HEAP_MAX_SIZE)
return -1;
- if(mprotect((char *)h + h->size, diff, PROT_READ|PROT_WRITE) != 0)
- return -2;
+ if((unsigned long) new_size > h->mprotect_size) {
+ if (mprotect((char *)h + h->mprotect_size,
+ (unsigned long) new_size - h->mprotect_size,
+ PROT_READ|PROT_WRITE) != 0)
+ return -2;
+ h->mprotect_size = new_size;
+ }
} else {
new_size = (long)h->size + diff;
if(new_size < (long)sizeof(*h))
return -1;
/* Try to re-map the extra heap space freshly to save memory, and
make it inaccessible. */
- if((char *)MMAP((char *)h + new_size, -diff, PROT_NONE,
- MAP_PRIVATE|MAP_FIXED) == (char *) MAP_FAILED)
- return -2;
+#ifdef _LIBC
+ if (__builtin_expect (__libc_enable_secure, 0))
+#else
+ if (1)
+#endif
+ {
+ if((char *)MMAP((char *)h + new_size, -diff, PROT_NONE,
+ MAP_PRIVATE|MAP_FIXED) == (char *) MAP_FAILED)
+ return -2;
+ h->mprotect_size = new_size;
+ }
+#ifdef _LIBC
+ else
+ madvise ((char *)h + new_size, -diff, MADV_DONTNEED);
+#endif
/*fprintf(stderr, "shrink %p %08lx\n", h, new_size);*/
}
h->size = new_size;