aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorUlrich Drepper <drepper@redhat.com>2007-12-12 00:11:49 +0000
committerUlrich Drepper <drepper@redhat.com>2007-12-12 00:11:49 +0000
commitcbf5760e629a71c4c7d66f4fbd7e47914e947879 (patch)
treeacfdb6eccc9008f9f623801515fd1fb762c36b68
parent17edb30c62d6e0d84f1e9b40e7df3a43b254f551 (diff)
downloadglibc-cbf5760e629a71c4c7d66f4fbd7e47914e947879.zip
glibc-cbf5760e629a71c4c7d66f4fbd7e47914e947879.tar.gz
glibc-cbf5760e629a71c4c7d66f4fbd7e47914e947879.tar.bz2
* malloc/arena.c (grow_heap): Split out code to shrink heap into...
(shrink_heap): ... this new function. (heap_trim): Call shrink_heap instead of grow_heap.
-rw-r--r--ChangeLog4
-rw-r--r--malloc/arena.c80
2 files changed, 51 insertions, 33 deletions
diff --git a/ChangeLog b/ChangeLog
index 531d6b9..c575591 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
2007-12-11 Ulrich Drepper <drepper@redhat.com>
+ * malloc/arena.c (grow_heap): Split out code to shrink heap into...
+ (shrink_heap): ... this new function.
+ (heap_trim): Call shrink_heap instead of grow_heap.
+
* malloc/malloc.c (_int_malloc): sYSMALLOc might fail, in this
case don't call alloc_perturb.
diff --git a/malloc/arena.c b/malloc/arena.c
index 4cbb4dc..9932ee0 100644
--- a/malloc/arena.c
+++ b/malloc/arena.c
@@ -704,8 +704,8 @@ new_heap(size, top_pad) size_t size, top_pad;
return h;
}
-/* Grow or shrink a heap. size is automatically rounded up to a
- multiple of the page size if it is positive. */
+/* Grow a heap. size is automatically rounded up to a
+ multiple of the page size. */
static int
#if __STD_C
@@ -717,41 +717,55 @@ grow_heap(h, diff) heap_info *h; long diff;
size_t page_mask = malloc_getpagesize - 1;
long new_size;
- if(diff >= 0) {
- diff = (diff + page_mask) & ~page_mask;
- new_size = (long)h->size + diff;
- if((unsigned long) new_size > (unsigned long) HEAP_MAX_SIZE)
- return -1;
- 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. */
+ diff = (diff + page_mask) & ~page_mask;
+ new_size = (long)h->size + diff;
+ if((unsigned long) new_size > (unsigned long) HEAP_MAX_SIZE)
+ return -1;
+ 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;
+ }
+
+ h->size = new_size;
+ return 0;
+}
+
+/* Shrink a heap. */
+
+static int
+#if __STD_C
+shrink_heap(heap_info *h, long diff)
+#else
+shrink_heap(h, diff) heap_info *h; long diff;
+#endif
+{
+ long new_size;
+
+ 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. */
#ifdef _LIBC
- if (__builtin_expect (__libc_enable_secure, 0))
+ if (__builtin_expect (__libc_enable_secure, 0))
#else
- if (1)
+ 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;
- }
+ {
+ 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);
+ else
+ madvise ((char *)h + new_size, diff, MADV_DONTNEED);
#endif
- /*fprintf(stderr, "shrink %p %08lx\n", h, new_size);*/
- }
+ /*fprintf(stderr, "shrink %p %08lx\n", h, new_size);*/
+
h->size = new_size;
return 0;
}
@@ -811,7 +825,7 @@ heap_trim(heap, pad) heap_info *heap; size_t pad;
if(extra < (long)pagesz)
return 0;
/* Try to shrink. */
- if(grow_heap(heap, -extra) != 0)
+ if(shrink_heap(heap, extra) != 0)
return 0;
ar_ptr->system_mem -= extra;
arena_mem -= extra;