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Diffstat (limited to 'src/malloc/malloc.c')
-rw-r--r--src/malloc/malloc.c91
1 files changed, 45 insertions, 46 deletions
diff --git a/src/malloc/malloc.c b/src/malloc/malloc.c
index 207b6ef2..db4287ef 100644
--- a/src/malloc/malloc.c
+++ b/src/malloc/malloc.c
@@ -16,9 +16,8 @@ void *__mremap(void *, size_t, size_t, int, ...);
int __madvise(void *, size_t, int);
struct chunk {
- size_t data[1];
- struct chunk *next;
- struct chunk *prev;
+ size_t psize, csize;
+ struct chunk *next, *prev;
};
struct bin {
@@ -44,19 +43,19 @@ static struct {
#define DONTCARE 16
#define RECLAIM 163840
-#define CHUNK_SIZE(c) ((c)->data[0] & SIZE_MASK)
-#define CHUNK_PSIZE(c) ((c)->data[-1] & SIZE_MASK)
+#define CHUNK_SIZE(c) ((c)->csize & SIZE_MASK)
+#define CHUNK_PSIZE(c) ((c)->psize & SIZE_MASK)
#define PREV_CHUNK(c) ((struct chunk *)((char *)(c) - CHUNK_PSIZE(c)))
#define NEXT_CHUNK(c) ((struct chunk *)((char *)(c) + CHUNK_SIZE(c)))
-#define MEM_TO_CHUNK(p) (struct chunk *)((size_t *)p - 1)
-#define CHUNK_TO_MEM(c) (void *)((c)->data+1)
+#define MEM_TO_CHUNK(p) (struct chunk *)((char *)(p) - OVERHEAD)
+#define CHUNK_TO_MEM(c) (void *)((char *)(c) + OVERHEAD)
#define BIN_TO_CHUNK(i) (MEM_TO_CHUNK(&mal.bins[i].head))
#define C_INUSE ((size_t)1)
#define C_FLAGS ((size_t)3)
#define C_SIZE SIZE_MASK
-#define IS_MMAPPED(c) !((c)->data[0] & (C_INUSE))
+#define IS_MMAPPED(c) !((c)->csize & (C_INUSE))
/* Synchronization tools */
@@ -138,8 +137,8 @@ void __dump_heap(int x)
for (c = (void *)mal.heap; CHUNK_SIZE(c); c = NEXT_CHUNK(c))
fprintf(stderr, "base %p size %zu (%d) flags %d/%d\n",
c, CHUNK_SIZE(c), bin_index(CHUNK_SIZE(c)),
- c->data[0] & 15,
- NEXT_CHUNK(c)->data[-1] & 15);
+ c->csize & 15,
+ NEXT_CHUNK(c)->psize & 15);
for (i=0; i<64; i++) {
if (mal.bins[i].head != BIN_TO_CHUNK(i) && mal.bins[i].head) {
fprintf(stderr, "bin %d: %p\n", i, mal.bins[i].head);
@@ -165,11 +164,11 @@ static struct chunk *expand_heap(size_t n)
if (__brk(new) != new) goto fail;
w = MEM_TO_CHUNK(new);
- w->data[-1] = n | C_INUSE;
- w->data[0] = 0 | C_INUSE;
+ w->psize = n | C_INUSE;
+ w->csize = 0 | C_INUSE;
w = MEM_TO_CHUNK(mal.brk);
- w->data[0] = n | C_INUSE;
+ w->csize = n | C_INUSE;
mal.brk = new;
unlock(mal.brk_lock);
@@ -206,7 +205,7 @@ static int init_malloc(size_t n)
}
mal.heap = (void *)c;
- c->data[-1] = 0 | C_INUSE;
+ c->psize = 0 | C_INUSE;
free(CHUNK_TO_MEM(c));
a_store(&init, 2);
@@ -236,18 +235,18 @@ static void unbin(struct chunk *c, int i)
a_and_64(&mal.binmap, ~(1ULL<<i));
c->prev->next = c->next;
c->next->prev = c->prev;
- c->data[0] |= C_INUSE;
- NEXT_CHUNK(c)->data[-1] |= C_INUSE;
+ c->csize |= C_INUSE;
+ NEXT_CHUNK(c)->psize |= C_INUSE;
}
static int alloc_fwd(struct chunk *c)
{
int i;
size_t k;
- while (!((k=c->data[0]) & C_INUSE)) {
+ while (!((k=c->csize) & C_INUSE)) {
i = bin_index(k);
lock_bin(i);
- if (c->data[0] == k) {
+ if (c->csize == k) {
unbin(c, i);
unlock_bin(i);
return 1;
@@ -261,10 +260,10 @@ static int alloc_rev(struct chunk *c)
{
int i;
size_t k;
- while (!((k=c->data[-1]) & C_INUSE)) {
+ while (!((k=c->psize) & C_INUSE)) {
i = bin_index(k);
lock_bin(i);
- if (c->data[-1] == k) {
+ if (c->psize == k) {
unbin(PREV_CHUNK(c), i);
unlock_bin(i);
return 1;
@@ -301,10 +300,10 @@ static int pretrim(struct chunk *self, size_t n, int i, int j)
split->next = self->next;
split->prev->next = split;
split->next->prev = split;
- split->data[-1] = n | C_INUSE;
- split->data[0] = n1-n;
- next->data[-1] = n1-n;
- self->data[0] = n | C_INUSE;
+ split->psize = n | C_INUSE;
+ split->csize = n1-n;
+ next->psize = n1-n;
+ self->csize = n | C_INUSE;
return 1;
}
@@ -318,10 +317,10 @@ static void trim(struct chunk *self, size_t n)
next = NEXT_CHUNK(self);
split = (void *)((char *)self + n);
- split->data[-1] = n | C_INUSE;
- split->data[0] = n1-n | C_INUSE;
- next->data[-1] = n1-n | C_INUSE;
- self->data[0] = n | C_INUSE;
+ split->psize = n | C_INUSE;
+ split->csize = n1-n | C_INUSE;
+ next->psize = n1-n | C_INUSE;
+ self->csize = n | C_INUSE;
free(CHUNK_TO_MEM(split));
}
@@ -338,9 +337,9 @@ void *malloc(size_t n)
char *base = __mmap(0, len, PROT_READ|PROT_WRITE,
MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
if (base == (void *)-1) return 0;
- c = (void *)(base + SIZE_ALIGN - sizeof(size_t));
- c->data[0] = len - (SIZE_ALIGN - sizeof(size_t));
- c->data[-1] = SIZE_ALIGN - sizeof(size_t);
+ c = (void *)(base + SIZE_ALIGN - OVERHEAD);
+ c->csize = len - (SIZE_ALIGN - OVERHEAD);
+ c->psize = SIZE_ALIGN - OVERHEAD;
return CHUNK_TO_MEM(c);
}
@@ -354,15 +353,15 @@ void *malloc(size_t n)
if (alloc_rev(c)) {
struct chunk *x = c;
c = PREV_CHUNK(c);
- NEXT_CHUNK(x)->data[-1] = c->data[0] =
- x->data[0] + CHUNK_SIZE(c);
+ NEXT_CHUNK(x)->psize = c->csize =
+ x->csize + CHUNK_SIZE(c);
}
break;
}
j = first_set(mask);
lock_bin(j);
c = mal.bins[j].head;
- if (c != BIN_TO_CHUNK(j) && j == bin_index(c->data[0])) {
+ if (c != BIN_TO_CHUNK(j) && j == bin_index(c->csize)) {
if (!pretrim(c, n, i, j)) unbin(c, j);
unlock_bin(j);
break;
@@ -390,7 +389,7 @@ void *realloc(void *p, size_t n)
n1 = n0 = CHUNK_SIZE(self);
if (IS_MMAPPED(self)) {
- size_t extra = self->data[-1];
+ size_t extra = self->psize;
char *base = (char *)self - extra;
size_t oldlen = n0 + extra;
size_t newlen = n + extra;
@@ -407,7 +406,7 @@ void *realloc(void *p, size_t n)
if (base == (void *)-1)
return newlen < oldlen ? p : 0;
self = (void *)(base + extra);
- self->data[0] = newlen - extra;
+ self->csize = newlen - extra;
return CHUNK_TO_MEM(self);
}
@@ -425,8 +424,8 @@ void *realloc(void *p, size_t n)
self = PREV_CHUNK(self);
n1 += CHUNK_SIZE(self);
}
- self->data[0] = n1 | C_INUSE;
- next->data[-1] = n1 | C_INUSE;
+ self->csize = n1 | C_INUSE;
+ next->psize = n1 | C_INUSE;
/* If we got enough space, split off the excess and return */
if (n <= n1) {
@@ -454,7 +453,7 @@ void free(void *p)
if (!p) return;
if (IS_MMAPPED(self)) {
- size_t extra = self->data[-1];
+ size_t extra = self->psize;
char *base = (char *)self - extra;
size_t len = CHUNK_SIZE(self) + extra;
/* Crash on double free */
@@ -468,7 +467,7 @@ void free(void *p)
for (;;) {
/* Replace middle of large chunks with fresh zero pages */
- if (reclaim && (self->data[-1] & next->data[0] & C_INUSE)) {
+ if (reclaim && (self->psize & next->csize & C_INUSE)) {
uintptr_t a = (uintptr_t)self + SIZE_ALIGN+PAGE_SIZE-1 & -PAGE_SIZE;
uintptr_t b = (uintptr_t)next - SIZE_ALIGN & -PAGE_SIZE;
#if 1
@@ -479,13 +478,13 @@ void free(void *p)
#endif
}
- if (self->data[-1] & next->data[0] & C_INUSE) {
- self->data[0] = final_size | C_INUSE;
- next->data[-1] = final_size | C_INUSE;
+ if (self->psize & next->csize & C_INUSE) {
+ self->csize = final_size | C_INUSE;
+ next->psize = final_size | C_INUSE;
i = bin_index(final_size);
lock_bin(i);
lock(mal.free_lock);
- if (self->data[-1] & next->data[0] & C_INUSE)
+ if (self->psize & next->csize & C_INUSE)
break;
unlock(mal.free_lock);
unlock_bin(i);
@@ -508,8 +507,8 @@ void free(void *p)
}
}
- self->data[0] = final_size;
- next->data[-1] = final_size;
+ self->csize = final_size;
+ next->psize = final_size;
unlock(mal.free_lock);
self->next = BIN_TO_CHUNK(i);
generated by cgit v1.2.1 (git 2.18.0) at 2024-11-16 14:12:41 +0000