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authorSverker Eriksson <[email protected]>2013-09-02 15:30:02 +0200
committerSverker Eriksson <[email protected]>2013-09-30 17:45:44 +0200
commit5e4a2c0cd69736ee1b1f54f8bb63a68688bc84e8 (patch)
treee95b99d1c352ce7e8d9668a9a26ad17ba94e1bc4
parentef3da907bd566b43a4022f1cbb1ae3d103b9ec3e (diff)
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erts: Save one word in ErtsFreeSegDesc
by putting red/black color bit in 'parent' pointer
-rw-r--r--erts/emulator/sys/common/erl_mmap.c298
1 files changed, 155 insertions, 143 deletions
diff --git a/erts/emulator/sys/common/erl_mmap.c b/erts/emulator/sys/common/erl_mmap.c
index aac01bf93c..cd71127ce5 100644
--- a/erts/emulator/sys/common/erl_mmap.c
+++ b/erts/emulator/sys/common/erl_mmap.c
@@ -83,16 +83,43 @@ UWord erts_page_inv_mask;
typedef struct RBTNode_ RBTNode;
struct RBTNode_ {
- RBTNode *parent;
+ UWord parent_and_color; /* color in bit 0 of parent ptr */
RBTNode *left;
RBTNode *right;
+#ifdef HARD_DEBUG
int flags;
+#endif
};
+#define RED_FLG (1)
+#define IS_RED(N) ((N) && ((N)->parent_and_color & RED_FLG))
+#define IS_BLACK(N) (!IS_RED(N))
+#define SET_RED(N) ((N)->parent_and_color |= RED_FLG)
+#define SET_BLACK(N) ((N)->parent_and_color &= ~RED_FLG)
+
+static ERTS_INLINE RBTNode* parent(RBTNode* node)
+{
+ return (RBTNode*) (node->parent_and_color & ~RED_FLG);
+}
+
+static ERTS_INLINE void set_parent(RBTNode* node, RBTNode* parent)
+{
+ RBT_ASSERT(!((UWord)parent & RED_FLG));
+ node->parent_and_color = ((UWord)parent) | (node->parent_and_color & RED_FLG);
+}
+
+static ERTS_INLINE UWord parent_and_color(RBTNode* parent, int color)
+{
+ RBT_ASSERT(!((UWord)parent & RED_FLG));
+ RBT_ASSERT(!(color & ~RED_FLG));
+ return ((UWord)parent) | color;
+}
+
+
enum SortOrder {
- ADDR_ORDER,
- SZ_ADDR_ORDER,
- SZ_REVERSE_ADDR_ORDER
+ ADDR_ORDER, /* only address order */
+ SZ_ADDR_ORDER, /* first size then address order as tiebreaker */
+ SZ_REVERSE_ADDR_ORDER /* first size then reverse address order */
};
typedef struct {
@@ -100,13 +127,6 @@ typedef struct {
enum SortOrder order;
}RBTree;
-#define RED_FLG (1)
-#define IS_RED(N) ((N) && ((N)->flags & RED_FLG))
-#define IS_BLACK(N) (!IS_RED(N))
-#define SET_RED(N) ((N)->flags |= RED_FLG)
-#define SET_BLACK(N) ((N)->flags &= ~RED_FLG)
-
-/* #define HARD_DEBUG */
#ifdef HARD_DEBUG
# define HARD_CHECK_IS_MEMBER(ROOT,NODE) rbt_assert_is_member(ROOT,NODE)
# define HARD_CHECK_TREE(TREE,SZ) check_tree(TREE, SZ)
@@ -318,20 +338,20 @@ left_rotate(RBTNode **root, RBTNode *x)
RBTNode *y = x->right;
x->right = y->left;
if (y->left)
- y->left->parent = x;
- y->parent = x->parent;
- if (!y->parent) {
+ set_parent(y->left, x);
+ set_parent(y, parent(x));
+ if (!parent(y)) {
RBT_ASSERT(*root == x);
*root = y;
}
- else if (x == x->parent->left)
- x->parent->left = y;
+ else if (x == parent(x)->left)
+ parent(x)->left = y;
else {
- RBT_ASSERT(x == x->parent->right);
- x->parent->right = y;
+ RBT_ASSERT(x == parent(x)->right);
+ parent(x)->right = y;
}
y->left = x;
- x->parent = y;
+ set_parent(x, y);
/*SVERK y->max_sz = x->max_sz;
x->max_sz = node_max_size(x);
@@ -344,20 +364,20 @@ right_rotate(RBTNode **root, RBTNode *x)
RBTNode *y = x->left;
x->left = y->right;
if (y->right)
- y->right->parent = x;
- y->parent = x->parent;
- if (!y->parent) {
+ set_parent(y->right, x);
+ set_parent(y, parent(x));
+ if (!parent(y)) {
RBT_ASSERT(*root == x);
*root = y;
}
- else if (x == x->parent->right)
- x->parent->right = y;
+ else if (x == parent(x)->right)
+ parent(x)->right = y;
else {
- RBT_ASSERT(x == x->parent->left);
- x->parent->left = y;
+ RBT_ASSERT(x == parent(x)->left);
+ parent(x)->left = y;
}
y->right = x;
- x->parent = y;
+ set_parent(x, y);
/*SVERK y->max_sz = x->max_sz;
x->max_sz = node_max_size(x);
ASSERT(y->max_sz >= x->max_sz);*/
@@ -371,27 +391,27 @@ static ERTS_INLINE void
replace(RBTNode **root, RBTNode *x, RBTNode *y)
{
- if (!x->parent) {
+ if (!parent(x)) {
RBT_ASSERT(*root == x);
*root = y;
}
- else if (x == x->parent->left)
- x->parent->left = y;
+ else if (x == parent(x)->left)
+ parent(x)->left = y;
else {
- RBT_ASSERT(x == x->parent->right);
- x->parent->right = y;
+ RBT_ASSERT(x == parent(x)->right);
+ parent(x)->right = y;
}
if (x->left) {
- RBT_ASSERT(x->left->parent == x);
- x->left->parent = y;
+ RBT_ASSERT(parent(x->left) == x);
+ set_parent(x->left, y);
}
if (x->right) {
- RBT_ASSERT(x->right->parent == x);
- x->right->parent = y;
+ RBT_ASSERT(parent(x->right) == x);
+ set_parent(x->right, y);
}
- y->flags = x->flags;
- y->parent = x->parent;
+ /*y->flags = x->flags;*/
+ y->parent_and_color = x->parent_and_color;
y->right = x->right;
y->left = x->left;
/*SVERK y->max_sz = x->max_sz;*/
@@ -406,7 +426,7 @@ tree_insert_fixup(RBTNode** root, RBTNode *blk)
* Rearrange the tree so that it satisfies the Red-Black Tree properties
*/
- RBT_ASSERT(x != *root && IS_RED(x->parent));
+ RBT_ASSERT(x != *root && IS_RED(parent(x)));
do {
/*
@@ -415,77 +435,77 @@ tree_insert_fixup(RBTNode** root, RBTNode *blk)
*/
RBT_ASSERT(IS_RED(x));
- RBT_ASSERT(IS_BLACK(x->parent->parent));
- RBT_ASSERT(x->parent->parent);
+ RBT_ASSERT(IS_BLACK(parent(parent(x))));
+ RBT_ASSERT(parent(parent(x)));
- if (x->parent == x->parent->parent->left) {
- y = x->parent->parent->right;
+ if (parent(x) == parent(parent(x))->left) {
+ y = parent(parent(x))->right;
if (IS_RED(y)) {
SET_BLACK(y);
- x = x->parent;
+ x = parent(x);
SET_BLACK(x);
- x = x->parent;
+ x = parent(x);
SET_RED(x);
}
else {
- if (x == x->parent->right) {
- x = x->parent;
+ if (x == parent(x)->right) {
+ x = parent(x);
left_rotate(root, x);
}
- RBT_ASSERT(x == x->parent->parent->left->left);
+ RBT_ASSERT(x == parent(parent(x))->left->left);
RBT_ASSERT(IS_RED(x));
- RBT_ASSERT(IS_RED(x->parent));
- RBT_ASSERT(IS_BLACK(x->parent->parent));
+ RBT_ASSERT(IS_RED(parent(x)));
+ RBT_ASSERT(IS_BLACK(parent(parent(x))));
RBT_ASSERT(IS_BLACK(y));
- SET_BLACK(x->parent);
- SET_RED(x->parent->parent);
- right_rotate(root, x->parent->parent);
+ SET_BLACK(parent(x));
+ SET_RED(parent(parent(x)));
+ right_rotate(root, parent(parent(x)));
- RBT_ASSERT(x == x->parent->left);
+ RBT_ASSERT(x == parent(x)->left);
RBT_ASSERT(IS_RED(x));
- RBT_ASSERT(IS_RED(x->parent->right));
- RBT_ASSERT(IS_BLACK(x->parent));
+ RBT_ASSERT(IS_RED(parent(x)->right));
+ RBT_ASSERT(IS_BLACK(parent(x)));
break;
}
}
else {
- RBT_ASSERT(x->parent == x->parent->parent->right);
- y = x->parent->parent->left;
+ RBT_ASSERT(parent(x) == parent(parent(x))->right);
+ y = parent(parent(x))->left;
if (IS_RED(y)) {
SET_BLACK(y);
- x = x->parent;
+ x = parent(x);
SET_BLACK(x);
- x = x->parent;
+ x = parent(x);
SET_RED(x);
}
else {
- if (x == x->parent->left) {
- x = x->parent;
+ if (x == parent(x)->left) {
+ x = parent(x);
right_rotate(root, x);
}
- RBT_ASSERT(x == x->parent->parent->right->right);
+ RBT_ASSERT(x == parent(parent(x))->right->right);
RBT_ASSERT(IS_RED(x));
- RBT_ASSERT(IS_RED(x->parent));
- RBT_ASSERT(IS_BLACK(x->parent->parent));
+ RBT_ASSERT(IS_RED(parent(x)));
+ RBT_ASSERT(IS_BLACK(parent(parent(x))));
RBT_ASSERT(IS_BLACK(y));
- SET_BLACK(x->parent);
- SET_RED(x->parent->parent);
- left_rotate(root, x->parent->parent);
+ SET_BLACK(parent(x));
+ SET_RED(parent(parent(x)));
+ left_rotate(root, parent(parent(x)));
- RBT_ASSERT(x == x->parent->right);
+ RBT_ASSERT(x == parent(x)->right);
RBT_ASSERT(IS_RED(x));
- RBT_ASSERT(IS_RED(x->parent->left));
- RBT_ASSERT(IS_BLACK(x->parent));
+ RBT_ASSERT(IS_RED(parent(x)->left));
+ RBT_ASSERT(IS_BLACK(parent(x)));
break;
}
}
- } while (x != *root && IS_RED(x->parent));
+ } while (x != *root && IS_RED(parent(x)));
SET_BLACK(*root);
}
@@ -500,7 +520,7 @@ rbt_delete(RBTNode** root, RBTNode* del)
HARD_CHECK_IS_MEMBER(*root, del);
- null_x.parent = NULL;
+ null_x.parent_and_color = parent_and_color(NULL, !RED_FLG);
/* Remove node from tree... */
@@ -514,29 +534,29 @@ rbt_delete(RBTNode** root, RBTNode* del)
x = y->left ? y->left : y->right;
spliced_is_black = IS_BLACK(y);
if (x) {
- x->parent = y->parent;
+ set_parent(x, parent(y));
}
else if (spliced_is_black) {
x = &null_x;
- x->flags = 0;
- SET_BLACK(x);
+ /*x->flags = 0;
+ SET_BLACK(x);*/
x->right = x->left = NULL;
/*SVERK x->max_sz = 0;*/
- x->parent = y->parent;
+ x->parent_and_color = parent_and_color(parent(y), !RED_FLG);
y->left = x;
}
- if (!y->parent) {
+ if (!parent(y)) {
RBT_ASSERT(*root == y);
*root = x;
}
else {
- if (y == y->parent->left) {
- y->parent->left = x;
+ if (y == parent(y)->left) {
+ parent(y)->left = x;
}
else {
- RBT_ASSERT(y == y->parent->right);
- y->parent->right = x;
+ RBT_ASSERT(y == parent(y)->right);
+ parent(y)->right = x;
}
/*SVERK if (y->parent != z) {
lower_max_size(y->parent, (y==z ? NULL : z));
@@ -553,7 +573,7 @@ rbt_delete(RBTNode** root, RBTNode* del)
/* We removed a black node which makes the resulting tree
violate the Red-Black Tree properties. Fixup tree... */
- while (IS_BLACK(x) && x->parent) {
+ while (IS_BLACK(x) && parent(x)) {
/*
* x has an "extra black" which we move up the tree
@@ -562,78 +582,78 @@ rbt_delete(RBTNode** root, RBTNode* del)
* y is the sibbling of x
*/
- if (x == x->parent->left) {
- y = x->parent->right;
+ if (x == parent(x)->left) {
+ y = parent(x)->right;
RBT_ASSERT(y);
if (IS_RED(y)) {
RBT_ASSERT(y->right);
RBT_ASSERT(y->left);
SET_BLACK(y);
- RBT_ASSERT(IS_BLACK(x->parent));
- SET_RED(x->parent);
- left_rotate(root, x->parent);
- y = x->parent->right;
+ RBT_ASSERT(IS_BLACK(parent(x)));
+ SET_RED(parent(x));
+ left_rotate(root, parent(x));
+ y = parent(x)->right;
}
RBT_ASSERT(y);
RBT_ASSERT(IS_BLACK(y));
if (IS_BLACK(y->left) && IS_BLACK(y->right)) {
SET_RED(y);
- x = x->parent;
+ x = parent(x);
}
else {
if (IS_BLACK(y->right)) {
SET_BLACK(y->left);
SET_RED(y);
right_rotate(root, y);
- y = x->parent->right;
+ y = parent(x)->right;
}
RBT_ASSERT(y);
- if (IS_RED(x->parent)) {
+ if (IS_RED(parent(x))) {
- SET_BLACK(x->parent);
+ SET_BLACK(parent(x));
SET_RED(y);
}
RBT_ASSERT(y->right);
SET_BLACK(y->right);
- left_rotate(root, x->parent);
+ left_rotate(root, parent(x));
x = *root;
break;
}
}
else {
- RBT_ASSERT(x == x->parent->right);
- y = x->parent->left;
+ RBT_ASSERT(x == parent(x)->right);
+ y = parent(x)->left;
RBT_ASSERT(y);
if (IS_RED(y)) {
RBT_ASSERT(y->right);
RBT_ASSERT(y->left);
SET_BLACK(y);
- RBT_ASSERT(IS_BLACK(x->parent));
- SET_RED(x->parent);
- right_rotate(root, x->parent);
- y = x->parent->left;
+ RBT_ASSERT(IS_BLACK(parent(x)));
+ SET_RED(parent(x));
+ right_rotate(root, parent(x));
+ y = parent(x)->left;
}
RBT_ASSERT(y);
RBT_ASSERT(IS_BLACK(y));
if (IS_BLACK(y->right) && IS_BLACK(y->left)) {
SET_RED(y);
- x = x->parent;
+ x = parent(x);
}
else {
if (IS_BLACK(y->left)) {
SET_BLACK(y->right);
SET_RED(y);
left_rotate(root, y);
- y = x->parent->left;
+ y = parent(x)->left;
}
RBT_ASSERT(y);
- if (IS_RED(x->parent)) {
- SET_BLACK(x->parent);
+ if (IS_RED(parent(x))) {
+ SET_BLACK(parent(x));
SET_RED(y);
}
RBT_ASSERT(y->left);
SET_BLACK(y->left);
- right_rotate(root, x->parent);
+ right_rotate(root, parent(x));
x = *root;
break;
}
@@ -641,12 +661,12 @@ rbt_delete(RBTNode** root, RBTNode* del)
}
SET_BLACK(x);
- if (null_x.parent) {
- if (null_x.parent->left == &null_x)
- null_x.parent->left = NULL;
+ if (parent(&null_x)) {
+ if (parent(&null_x)->left == &null_x)
+ parent(&null_x)->left = NULL;
else {
- RBT_ASSERT(null_x.parent->right == &null_x);
- null_x.parent->right = NULL;
+ RBT_ASSERT(parent(&null_x)->right == &null_x);
+ parent(&null_x)->right = NULL;
}
RBT_ASSERT(!null_x.left);
RBT_ASSERT(!null_x.right);
@@ -671,14 +691,14 @@ rbt_insert(enum SortOrder order, RBTNode** root, RBTNode* blk)
SWord blk_sz = desc->end - desc->start;
/*SVERK Uint blk_sz = AOFF_BLK_SZ(blk);*/
- blk->flags = 0;
+ /*blk->flags = 0;*/
blk->left = NULL;
blk->right = NULL;
/*SVERK blk->max_sz = blk_sz;*/
if (!*root) {
- blk->parent = NULL;
- SET_BLACK(blk);
+ blk->parent_and_color = parent_and_color(NULL, !RED_FLG);
+ /*SET_BLACK(blk);*/
*root = blk;
}
else {
@@ -692,7 +712,7 @@ rbt_insert(enum SortOrder order, RBTNode** root, RBTNode* blk)
if (diff < 0) {
IF_RBT_DEBUG(dbg_over = node_to_desc(order, x));
if (!x->left) {
- blk->parent = x;
+ blk->parent_and_color = parent_and_color(x, RED_FLG);
x->left = blk;
break;
}
@@ -702,7 +722,7 @@ rbt_insert(enum SortOrder order, RBTNode** root, RBTNode* blk)
RBT_ASSERT(diff > 0);
IF_RBT_DEBUG(dbg_under = node_to_desc(order, x));
if (!x->right) {
- blk->parent = x;
+ blk->parent_and_color = parent_and_color(x, RED_FLG);
x->right = blk;
break;
}
@@ -723,15 +743,16 @@ rbt_insert(enum SortOrder order, RBTNode** root, RBTNode* blk)
}
/* Insert block into size tree */
- RBT_ASSERT(blk->parent);
+ RBT_ASSERT(parent(blk));
#ifdef RBT_DEBUG
if (!order) {
RBT_ASSERT(!dbg_under || dbg_under->end < desc->start);
RBT_ASSERT(!dbg_over || dbg_over->start > desc->end);
}
#endif
- SET_RED(blk);
- if (IS_RED(blk->parent))
+ /*SET_RED(blk);*/
+ RBT_ASSERT(IS_RED(blk));
+ if (IS_RED(parent(blk)))
tree_insert_fixup(root, blk);
}
/*SVERK if (flavor == AOFF_BF) {
@@ -1746,20 +1767,11 @@ erts_mmap_init(ErtsMMapInit *init)
mmap_state.supercarrier = 1;
erts_have_erts_mmap |= ERTS_HAVE_ERTS_SUPERCARRIER_MMAP;
-
-
-#ifdef HARD_DEBUG
- {
- void test_it(void);
- test_it();
}
-#endif
- }
#if !ERTS_HAVE_OS_MMAP
mmap_state.no_os_mmap = 1;
#endif
-
}
@@ -1773,9 +1785,9 @@ erts_mmap_init(ErtsMMapInit *init)
static int rbt_assert_is_member(RBTNode* root, RBTNode* node)
{
while (node != root) {
- RBT_ASSERT(node->parent);
- RBT_ASSERT(node->parent->left == node || node->parent->right == node);
- node = node->parent;
+ RBT_ASSERT(parent(node));
+ RBT_ASSERT(parent(node)->left == node || parent(node)->right == node);
+ node = parent(node);
}
return 1;
}
@@ -1841,7 +1853,7 @@ check_tree(RBTree* tree, Uint size)
x = tree->root;
RBT_ASSERT(IS_BLACK(x));
- RBT_ASSERT(!x->parent);
+ RBT_ASSERT(!parent(x));
curr_blacks = 1;
blacks = -1;
depth = 1;
@@ -1877,15 +1889,15 @@ check_tree(RBTree* tree, Uint size)
RBT_ASSERT(IS_BLACK(x->left));
}
- RBT_ASSERT(x->parent || x == tree->root);
+ RBT_ASSERT(parent(x) || x == tree->root);
if (x->left) {
- RBT_ASSERT(x->left->parent == x);
+ RBT_ASSERT(parent(x->left) == x);
RBT_ASSERT(cmp_blocks(tree->order, x->left, x) < 0);
}
if (x->right) {
- RBT_ASSERT(x->right->parent == x);
+ RBT_ASSERT(parent(x->right) == x);
RBT_ASSERT(cmp_blocks(tree->order, x->right, x) > 0);
}
@@ -1923,7 +1935,7 @@ check_tree(RBTree* tree, Uint size)
UNSET_RIGHT_VISITED(x);
if (IS_BLACK(x))
curr_blacks--;
- x = x->parent;
+ x = parent(x);
--depth;
}
RBT_ASSERT(depth == 0 || (!tree->root && depth==1));
@@ -1937,6 +1949,8 @@ check_tree(RBTree* tree, Uint size)
return res;
}
+#endif /* HARD_DEBUG */
+
#ifdef PRINT_TREE
#define INDENT_STEP 2
@@ -1983,13 +1997,13 @@ void test_it(void)
init_free_seg_map(&map, i);
insert_free_seg(&map, alloc_desc(), (char*)0x11000, (char*)0x12000);
- check_tree(&map.atree, 0); check_tree(&map.stree, 0);
+ HARD_CHECK_TREE(&map.atree, 0); HARD_CHECK_TREE(&map.stree, 0);
insert_free_seg(&map, alloc_desc(), (char*)0x13000, (char*)0x14000);
- check_tree(&map.atree, 0); check_tree(&map.stree, 0);
+ HARD_CHECK_TREE(&map.atree, 0); HARD_CHECK_TREE(&map.stree, 0);
insert_free_seg(&map, alloc_desc(), (char*)0x15000, (char*)0x17000);
- check_tree(&map.atree, 0); check_tree(&map.stree, 0);
+ HARD_CHECK_TREE(&map.atree, 0); HARD_CHECK_TREE(&map.stree, 0);
insert_free_seg(&map, alloc_desc(), (char*)0x8000, (char*)0x10000);
- check_tree(&map.atree, 0); check_tree(&map.stree, 0);
+ HARD_CHECK_TREE(&map.atree, 0); HARD_CHECK_TREE(&map.stree, 0);
desc = lookup_free_seg(&map, 0x500);
ERTS_ASSERT(desc->start == (char*)(i?0x13000L:0x11000L));
@@ -2026,17 +2040,15 @@ void test_it(void)
ERTS_ASSERT(d1->start == (char*)(i?0x13000L:0x11000L));
resize_free_seg(&map, d1, d1->start - 0x800, (char*)d1->end);
- check_tree(&map.atree, 0); check_tree(&map.stree, 0);
+ HARD_CHECK_TREE(&map.atree, 0); HARD_CHECK_TREE(&map.stree, 0);
d2 = lookup_free_seg(&map, 0x1200);
ERTS_ASSERT(d2 == d1);
delete_free_seg(&map, d1);
- check_tree(&map.atree, 0); check_tree(&map.stree, 0);
+ HARD_CHECK_TREE(&map.atree, 0); HARD_CHECK_TREE(&map.stree, 0);
d1 = lookup_free_seg(&map, 0x1200);
ERTS_ASSERT(d1->start == (char*)0x15000);
}
}
-
-#endif /* HARD_DEBUG */