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Got rbyd yellow splitting working

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This commit is contained in:
Christopher Haster
2022-12-26 21:57:24 -06:00
parent b48f7fcfb0
commit b03420ccfc
2 changed files with 419 additions and 375 deletions
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lfs.c
+83 -57
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@@ -394,6 +394,10 @@ static inline lfs_size_t lfs_tag_dsize(lfs_tag_t tag) {
return sizeof(tag) + lfs_tag_size(tag + lfs_tag_isdelete(tag));
}
// 32-bit metadata tags
//
// in-device, these are effectively 31-bit unsigned integers
// on-disk, these are encoded as leb128, so smaller constants are prefered
typedef uint32_t lfs_rtag_t;
typedef int32_t lfs_srtag_t;
@@ -416,15 +420,11 @@ enum lfs_rtag_type1 {
LFS_TYPE1_ALTRGT = 0x07,
};
enum lfs_rtag_color {
LFS_COLOR_B = 0,
LFS_COLOR_R = 1,
};
#define LFS_ALT_B false
#define LFS_ALT_R true
enum lfs_rtag_dir {
LFS_DIR_LT = 0,
LFS_DIR_GT = 1,
};
#define LFS_ALT_LT false
#define LFS_ALT_GT true
#define LFS_MKRTAG_(type1, type2, id) \
(((0x7f & (lfs_rtag_t)(type1)) << 0) \
@@ -441,8 +441,9 @@ enum lfs_rtag_dir {
| ((0xfffffff & (lfs_rtag_t)(weight)) << 3))
#define LFS_MKRALT(color, dir, weight) \
LFS_MKRALT_(LFS_COLOR_##color, LFS_DIR_##dir, weight)
LFS_MKRALT_(LFS_ALT_##color, LFS_ALT_##dir, weight)
// tag operations
static inline bool lfs_rtag_isvalid(lfs_rtag_t tag) {
return !(tag & 0x80000000);
}
@@ -471,6 +472,15 @@ static inline uint16_t lfs_rtag_id(lfs_rtag_t tag) {
return tag >> 15;
}
static inline lfs_rtag_t lfs_rtag_setid(lfs_rtag_t tag, uint16_t id) {
return (tag & 0x7fff) | ((lfs_rtag_t)id << 15);
}
static inline lfs_rtag_t lfs_rtag_inc(lfs_rtag_t tag) {
return tag + 0x8;
}
// alt operations
static inline bool lfs_rtag_isblack(lfs_rtag_t tag) {
return !(tag & 0x1);
}
@@ -479,6 +489,14 @@ static inline bool lfs_rtag_isred(lfs_rtag_t tag) {
return tag & 0x1;
}
static inline lfs_rtag_t lfs_rtag_red(lfs_rtag_t tag) {
return tag | 0x1;
}
static inline lfs_rtag_t lfs_rtag_black(lfs_rtag_t tag) {
return tag & ~0x1;
}
static inline bool lfs_rtag_islt(lfs_rtag_t tag) {
return !(tag & 0x2);
}
@@ -495,6 +513,10 @@ static inline lfs_srtag_t lfs_rtag_weight(lfs_rtag_t tag) {
return tag >> 3;
}
static inline lfs_rtag_t lfs_rtag_merge(lfs_rtag_t a, lfs_rtag_t b) {
return a + (b & ~0x7);
}
//static inline lfs_srtag_t lfs_rtag_weight2(lfs_rtag_t tag, lfs_rtag_t tag2) {
// return lfs_rtag_weight(tag) + lfs_rtag_weight(tag2);
//}
@@ -543,22 +565,6 @@ static inline void lfs_rtag_untrim(lfs_rtag_t alt,
}
}
static inline lfs_rtag_t lfs_rtag_inc(lfs_rtag_t tag) {
return tag + 0x8;
}
static inline lfs_rtag_t lfs_rtag_red(lfs_rtag_t tag) {
return tag | 0x1;
}
static inline lfs_rtag_t lfs_rtag_black(lfs_rtag_t tag) {
return tag & ~0x1;
}
static inline lfs_rtag_t lfs_rtag_setid(lfs_rtag_t tag, uint16_t id) {
return (tag & 0x7fff) | ((lfs_rtag_t)id << 15);
}
// operations on attribute lists
struct lfs_mattr {
lfs_tag_t tag;
@@ -1417,6 +1423,7 @@ static int lfs_rbyd_commit(lfs_t *lfs, lfs_rbyd_t *rbyd,
// append each tag to the tree
for (const struct lfs_rattr *attr = attrs; attr; attr = attr->next) {
printf("append()\n");
// assume we'll update our trunk
lfs_off_t branch = trunk;
trunk = off;
@@ -1453,6 +1460,19 @@ static int lfs_rbyd_commit(lfs_t *lfs, lfs_rbyd_t *rbyd,
jump = branch - jump;
lfs_rtag_t branch_ = branch + delta;
// // prune?
// printf("prune? %x >= %x (%x+%x+1)\n", lfs_rtag_weight(alt), lt+gt+1, lt, gt);
// if (lfs_rtag_weight(alt) >= lt+gt+1) {
// printf("prune!\n");
// LFS_ASSERT(p_alts[0]);
//
// branch = jump;
// branch_ = 0; // TODO is this needed?
// alt = lfs_rtag_black(p_alts[0]);
// jump = p_jumps[0];
// lfs_rbyd_p_pop(p_alts, p_jumps);
// }
// // prune?
// // TODO ugh, just clean this up later
// if (p_alts[0]
@@ -1476,38 +1496,44 @@ static int lfs_rbyd_commit(lfs_t *lfs, lfs_rbyd_t *rbyd,
// lfs_rbyd_p_pop(p_alts, p_jumps);
// }
//
//
// // split?
// if (lfs_rtag_isred(alt)
// && p_alts[0]
// && lfs_rtag_isred(p_alts[0])) {
// LFS_ASSERT(lfs_rtag_isparallel(alt, p_alts[0]));
//
// if (lfs_rtag_follow2(alt, p_alts[0], lt, gt)) {
// lfs_rtag_t alt_ = p_alts[0];
// lfs_off_t jump_ = p_jumps[0];
// p_alts[0] = lfs_rtag_black(
// lfs_rtag_flip2(alt, alt_, lt, gt));
// p_jumps[0] = jump;
// alt = lfs_rtag_black(alt_);
// jump = jump_;
//
// lfs_rtag_trim(alt_, &lt, &gt);
// lfs_rtag_trim(alt, &lt, &gt);
// lfs_rbyd_p_red(p_alts, p_jumps);
//
// } else {
// lfs_rtag_t alt_ = p_alts[0];
// p_alts[0] = lfs_rtag_black(alt);
// p_jumps[0] = xylem;
//
// lfs_rtag_trim(alt_, &lt, &gt);
// lfs_rtag_trim(alt, &lt, &gt);
// lfs_rbyd_p_red(p_alts, p_jumps);
//
// continue;
// }
// }
// two reds makes a yellow, split?
if (p_alts[0]
&& lfs_rtag_isred(p_alts[0])
&& lfs_rtag_isred(alt)) {
LFS_ASSERT(lfs_rtag_isparallel(alt, p_alts[0]));
// if we take the red or yellow alt we can just point
// to the black alt, otherwise we need to point to the
// yellow alt and prune later
if (lfs_rtag_follow(alt, lt, gt)) {
printf("ysplit follow\n");
lfs_rtag_t alt_ = p_alts[0];
lfs_off_t jump_ = p_jumps[0];
p_alts[0] = lfs_rtag_black(
lfs_rtag_flip(alt, lt, gt));
p_jumps[0] = branch_;
alt = lfs_rtag_black(alt_);
branch_ = jump;
jump = jump_;
lfs_rtag_untrim(alt, &lt, &gt);
lfs_rtag_trim(p_alts[0], &lt, &gt);
lfs_rbyd_p_red(p_alts, p_jumps);
} else {
printf("ysplit nofollow\n");
p_alts[0] = lfs_rtag_black(
lfs_rtag_merge(alt, p_alts[0]));
p_jumps[0] = xylem;
lfs_rtag_trim(alt, &lt, &gt);
lfs_rbyd_p_red(p_alts, p_jumps);
//xylem = branch;
branch = branch_;
continue;
}
}
// should've taken red alt? needs a flip
printf("lt,gt = (%x,%x)\n", lt, gt);