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Cleaned up post-mdir-commit state updates a bit

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This code is a bit tricky since we need to reference the current mdir to
know how to update other opened mdirs, but then also update the current
mdir, which could also be in the list of opened mdirs. I think a hear a
functional language user laughing in the distance...

            code          stack
  before:  33764           2832
  after:   33716 (-0.1%)   2832 (+0.0%)
This commit is contained in:
Christopher Haster
2024-02-08 22:51:43 -06:00
parent 307d60299f
commit 0fa33b7776
1 changed files with 49 additions and 60 deletions
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lfs.c
+49 -60
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@@ -6192,10 +6192,9 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
// reset gdelta for new commit
lfsr_fs_flushgdelta(lfs);
// parse out any pending gstate, these will get automatically
// xored with on-disk gdeltas in lower-level functions
for (lfs_size_t i = 0; i < attr_count; i++) {
// parse out any pending gstate, these will get automatically
// xored with on-disk gdeltas in lower-level functions
if (attrs[i].tag == LFSR_TAG_GRM) {
// encode to disk
lfsr_grm_t *grm = lfsr_attr_grm(&attrs[i]);
@@ -6397,7 +6396,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
uint8_t mdir_buf[LFSR_MPTR_DSIZE];
uint8_t msibling_buf[LFSR_MPTR_DSIZE];
err = lfsr_btree_commit(lfs, &mtree_.u.btree,
lfsr_mid_bid(lfs, mdir_.mid), LFSR_ATTRS(
lfsr_mid_bid(lfs, mdir->mid), LFSR_ATTRS(
LFSR_ATTR(
MDIR, 0,
FROMMPTR(lfsr_mdir_mptr(&mdir_), mdir_buf)),
@@ -6416,8 +6415,8 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
} else if (err == LFS_ERR_NOENT) {
LFS_DEBUG("Dropping mdir %"PRId32" "
"0x{%"PRIx32",%"PRIx32"}",
mdir_.mid >> lfs->mleaf_bits,
mdir_.rbyd.blocks[0], mdir_.rbyd.blocks[1]);
mdir->mid >> lfs->mleaf_bits,
mdir->rbyd.blocks[0], mdir->rbyd.blocks[1]);
// consume gstate so we don't lose any info
err = lfsr_fs_consumegdelta(lfs, mdir);
@@ -6437,7 +6436,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
// update our mtree
err = lfsr_btree_commit(lfs, &mtree_.u.btree,
lfsr_mid_bid(lfs, mdir_.mid), LFSR_ATTRS(
lfsr_mid_bid(lfs, mdir->mid), LFSR_ATTRS(
LFSR_ATTR(RM, -lfsr_mleafweight(lfs), NULL())));
if (err) {
return err;
@@ -6466,7 +6465,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
// update our mtree
uint8_t mdir_buf[LFSR_MPTR_DSIZE];
err = lfsr_btree_commit(lfs, &mtree_.u.btree,
lfsr_mid_bid(lfs, mdir_.mid), LFSR_ATTRS(
lfsr_mid_bid(lfs, mdir->mid), LFSR_ATTRS(
LFSR_ATTR(
MDIR, 0,
FROMMPTR(lfsr_mdir_mptr(&mdir_), mdir_buf))));
@@ -6659,56 +6658,24 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
}
}
// success? update in-device state, we must not error at this point
// update any opened mdirs in our mroot
for (lfsr_opened_t *o = lfs->opened; o; o = o->next) {
if (lfsr_mdir_cmp(&o->mdir, &lfs->mroot) == 0) {
o->mdir.rbyd = mroot_.rbyd;
// update staged changes
if (o->type == LFS_TYPE_REG) {
lfsr_file_t *file = (lfsr_file_t*)o;
file->bshrub = file->bshrub_;
}
}
}
// update mroot and mtree
lfs->mroot = mroot_;
lfs->mtree = mtree_;
// gstate must have been committed by a lower-level function at this point
LFS_ASSERT(lfsr_grm_iszero(lfs->grm_d));
// TODO merge with attr updates below?
// success? update in-device state, we must not error at this point
// play out any attrs that affect internal state
lfsr_smid_t mid = mdir->mid;
for (lfs_size_t i = 0; i < attr_count; i++) {
// update any gstate
// update any gstate changes
if (attrs[i].tag == LFSR_TAG_GRM) {
lfs->grm = *lfsr_attr_grm(&attrs[i]);
// keep track of the exact encoding on-disk
lfsr_data_fromgrm(&lfs->grm, lfs->grm_g);
}
}
for (lfsr_opened_t *o = lfs->opened;
o;
o = o->next) {
// update staged changes
if (o->type == LFS_TYPE_REG) {
lfsr_file_t *file = (lfsr_file_t*)o;
file->bshrub = file->bshrub_;
}
// avoid double updating current mdir
if (&o->mdir == mdir) {
continue;
}
// first play out any attrs that change our mid
lfsr_srid_t mid = mdir->mid;
for (lfs_size_t i = 0; i < attr_count; i++) {
// adjust any opened mdirs
for (lfsr_opened_t *o = lfs->opened; o; o = o->next) {
// adjust opened mdirs?
if (lfsr_mdir_cmp(&o->mdir, mdir) == 0
&& o->mdir.mid >= mid) {
@@ -6734,7 +6701,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
((lfsr_dir_t*)(o-1))->pos -= attrs[i].delta;
}
}
} else if (o->mdir.mid > mdir->mid) {
} else if (o->mdir.mid > mid) {
// adjust dir position?
if (o->type == LFS_TYPE_DIR) {
((lfsr_dir_t*)o)->pos += attrs[i].delta;
@@ -6742,18 +6709,36 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
((lfsr_dir_t*)(o-1))->pos -= attrs[i].delta;
}
}
// adjust mid
mid += attrs[i].delta;
if (lfsr_attr_isinsert(&attrs[i])) {
mid -= 1;
}
}
// update any opened mdirs if we had a split or drop
// adjust mid
mid += attrs[i].delta;
if (lfsr_attr_isinsert(&attrs[i])) {
mid -= 1;
}
}
// update any staged bsprouts/bshrubs
for (lfsr_opened_t *o = lfs->opened; o; o = o->next) {
if (o->type == LFS_TYPE_REG) {
lfsr_file_t *file = (lfsr_file_t*)o;
file->bshrub = file->bshrub_;
}
}
// update internal mdir state
for (lfsr_opened_t *o = lfs->opened; o; o = o->next) {
// avoid double updating the current mdir
if (&o->mdir == mdir) {
continue;
}
// update any splits/drops
if (lfsr_mdir_cmp(&o->mdir, mdir) == 0) {
LFS_ASSERT(mdir->mid != -1 || mdir == &lfs->mroot);
if (mdelta > 0
&& lfsr_mid_rid(lfs, o->mdir.mid) >= mdir_.rbyd.weight) {
&& lfsr_mid_rid(lfs, o->mdir.mid)
>= mdir_.rbyd.weight) {
o->mdir.mid += lfsr_mleafweight(lfs) - mdir_.rbyd.weight;
o->mdir.rbyd = msibling_.rbyd;
} else {
@@ -6765,16 +6750,20 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
}
// update mdir to follow requested rid
if (mdir->mid == -1) {
mdir->rbyd = lfs->mroot.rbyd;
} else if (mdelta > 0
&& lfsr_mid_rid(lfs, mdir->mid) >= mdir_.rbyd.weight) {
LFS_ASSERT(mdir->mid != -1 || mdir == &lfs->mroot);
if (mdelta > 0
&& lfsr_mid_rid(lfs, mdir->mid)
>= mdir_.rbyd.weight) {
mdir->mid += lfsr_mleafweight(lfs) - mdir_.rbyd.weight;
mdir->rbyd = msibling_.rbyd;
} else {
mdir->rbyd = mdir_.rbyd;
}
// update mroot and mtree
lfs->mroot = mroot_;
lfs->mtree = mtree_;
return 0;
}