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Added LFS_REVDBG, tweaked LFS_REVNOISE

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This tweaks a number of extended revision count things:

- Added LFS_REVDBG, which adds debug info to revision counts.

  This initializes the bottom 12 bits of every revision count with a
  hint based on rbyd type, which may be useful when debugging:

  - 68 69 21 v0 (hi!.) => mroot anchor
  - 6d 72 7e v0 (mr~.) => mroot
  - 6d 64 7e v0 (md~.) => mdir
  - 62 74 7e v0 (bt~.) => file btree node
  - 62 6d 7e v0 (bm~.) => mtree node

  This may be overwritten by the recycle counter if it overlaps, worst
  case the recycle counter takes up the entire revision count, but these
  have been chosen to at least keep some info if partially overwritten.

  To make this work required the LFS_i_INMTREE hack (yay global state),
  but a hack for debug info isn't the end of the world.

  Note we don't have control over data blocks, so there's always a
  chance they end up containing what looks like one of the above
  revision counts.

- Renamed LFS_NOISY -> LFS_REVNOISE

- LFS_REVDBG and LFS_REVNOISE are incompatible, so using both asserts.

  This also frees up the theoretical 0x00000030 state for an additional
  rev mode in the future.

- Adopted LFS_REVNOISE (and LFS_REVDBG) in btree nodes as well.

  If you need rev noise, you probably want it in all rbyds/metadata
  blocks, not just mdirs.

---

This had no effect on the default code size, but did affect
LFS_REVNOISE:

                    code          stack          ctx
  before:          35688           2440          640
  after:           35688 (+0.0%)   2440 (+0.0%)  640 (+0.0%)

  revnoise before: 35744           2440          640
  revnoise after:  35880 (+0.4%)   2440 (+0.0%)  640 (+0.0%)

  default:         35688           2440          640
  revdbg:          35912 (+0.6%)   2448 (+0.3%)  640 (+0.0%)
  revnoise:        35880 (+0.5%)   2440 (+0.0%)  640 (+0.0%)
This commit is contained in:
Christopher Haster
2025-04-21 13:45:36 -05:00
parent 7cd4c1f12f
commit 96eb38c8c2
6 changed files with 262 additions and 47 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lfs.c
+190 -21
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@@ -5418,6 +5418,9 @@ typedef struct lfsr_bctx {
uint8_t buf[2*LFSR_BRANCH_DSIZE];
} lfsr_bctx_t;
// needed in lfsr_btree_commit_
static inline uint32_t lfsr_rev_btree(lfs_t *lfs);
// core btree algorithm
//
// this commits up to the root, but stops if:
@@ -5651,6 +5654,18 @@ static int lfsr_btree_commit_(lfs_t *lfs, lfsr_btree_t *btree,
return err;
}
#if defined(LFS_REVDBG) || defined(LFS_REVNOISE)
// append a revision count?
err = lfsr_rbyd_appendrev(lfs, &rbyd__, lfsr_rev_btree(lfs));
if (err) {
// bad prog? try another block
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
#endif
// try to compact
err = lfsr_rbyd_compact(lfs, &rbyd__, &rbyd_, -1, -1);
if (err) {
@@ -5689,6 +5704,18 @@ static int lfsr_btree_commit_(lfs_t *lfs, lfsr_btree_t *btree,
return err;
}
#if defined(LFS_REVDBG) || defined(LFS_REVNOISE)
// append a revision count?
err = lfsr_rbyd_appendrev(lfs, &rbyd__, lfsr_rev_btree(lfs));
if (err) {
// bad prog? try another block
if (err == LFS_ERR_CORRUPT) {
goto split_relocate_l;
}
return err;
}
#endif
// copy over tags < split_rid
err = lfsr_rbyd_compact(lfs, &rbyd__, &rbyd_, -1, split_rid);
if (err) {
@@ -5733,6 +5760,18 @@ static int lfsr_btree_commit_(lfs_t *lfs, lfsr_btree_t *btree,
return err;
}
#if defined(LFS_REVDBG) || defined(LFS_REVNOISE)
// append a revision count?
err = lfsr_rbyd_appendrev(lfs, &sibling, lfsr_rev_btree(lfs));
if (err) {
// bad prog? try another block
if (err == LFS_ERR_CORRUPT) {
goto split_relocate_r;
}
return err;
}
#endif
// copy over tags >= split_rid
err = lfsr_rbyd_compact(lfs, &sibling, &rbyd_, split_rid, -1);
if (err) {
@@ -5849,6 +5888,18 @@ static int lfsr_btree_commit_(lfs_t *lfs, lfsr_btree_t *btree,
return err;
}
#if defined(LFS_REVDBG) || defined(LFS_REVNOISE)
// append a revision count?
err = lfsr_rbyd_appendrev(lfs, &rbyd__, lfsr_rev_btree(lfs));
if (err) {
// bad prog? try another block
if (err == LFS_ERR_CORRUPT) {
goto merge_relocate;
}
return err;
}
#endif
// merge the siblings together
err = lfsr_rbyd_appendcompactrbyd(lfs, &rbyd__, &rbyd_, -1, -1);
if (err) {
@@ -5991,6 +6042,18 @@ static int lfsr_btree_commit(lfs_t *lfs, lfsr_btree_t *btree,
return err;
}
#if defined(LFS_REVDBG) || defined(LFS_REVNOISE)
// append a revision count?
err = lfsr_rbyd_appendrev(lfs, &rbyd_, lfsr_rev_btree(lfs));
if (err) {
// bad prog? try another block
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
#endif
err = lfsr_rbyd_commit(lfs, &rbyd_, bid, rattrs, rattr_count);
if (err) {
LFS_ASSERT(err != LFS_ERR_RANGE);
@@ -6630,6 +6693,18 @@ relocate:;
return err;
}
#if defined(LFS_REVDBG) || defined(LFS_REVNOISE)
// append a revision count?
err = lfsr_rbyd_appendrev(lfs, &bshrub->shrub_, lfsr_rev_btree(lfs));
if (err) {
// bad prog? try another block
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
#endif
// note this may be a new root
if (!alloc) {
err = lfsr_rbyd_compact(lfs, &bshrub->shrub_, &bshrub->shrub, -1, -1);
@@ -6887,9 +6962,15 @@ static inline bool lfsr_m_isrdonly(uint32_t flags) {
return flags & LFS_M_RDONLY;
}
#ifdef LFS_NOISY
static inline bool lfsr_m_isnoisy(uint32_t flags) {
return flags & LFS_M_NOISY;
#ifdef LFS_REVDBG
static inline bool lfsr_m_isrevdbg(uint32_t flags) {
return flags & LFS_M_REVDBG;
}
#endif
#ifdef LFS_REVNOISE
static inline bool lfsr_m_isrevnoise(uint32_t flags) {
return flags & LFS_M_REVNOISE;
}
#endif
@@ -6917,6 +6998,13 @@ static inline bool lfsr_m_isckdatacksums(uint32_t flags) {
}
#endif
// other internal flags
#ifdef LFS_REVDBG
static inline bool lfsr_i_isinmtree(uint32_t flags) {
return flags & LFS_i_INMTREE;
}
#endif
/// opened mdir things ///
@@ -7203,23 +7291,79 @@ static int lfsr_fs_consumegdelta(lfs_t *lfs, const lfsr_mdir_t *mdir) {
// '-.''----.----''---------.--------'
// '------|---------------|---------- 4-bit relocation revision
// '---------------|---------- recycle-bits recycle counter
// '---------- pseudorandom noise (optional)
// '---------- pseudorandom noise (if revnoise)
//
// in revdbg mode, the bottom 24 bits are initialized with a hint based
// on rbyd type, though it may be overwritten by the recycle counter if
// it overlaps:
//
// vvvv---- --1----1 -11-1--1 -11-1--- (68 69 21 v0 hi!.) mroot anchor
// vvvv---- -111111- -111--1- -11-11-1 (6d 72 7e v0 mr~.) mroot
// vvvv---- -111111- -11--1-- -11-11-1 (6d 64 7e v0 md~.) mdir
// vvvv---- -111111- -111-1-- -11---1- (62 74 7e v0 bt~.) file btree node
// vvvv---- -111111- -11-11-1 -11---1- (62 6d 7e v0 bm~.) mtree node
//
static inline uint32_t lfsr_rev_init(lfs_t *lfs, uint32_t rev) {
// needed in lfsr_rev_init
static inline bool lfsr_mdir_ismrootanchor(const lfsr_mdir_t *mdir);
static inline int lfsr_mdir_cmp(const lfsr_mdir_t *a, const lfsr_mdir_t *b);
static inline uint32_t lfsr_rev_init(lfs_t *lfs, const lfsr_mdir_t *mdir,
uint32_t rev) {
(void)lfs;
(void)mdir;
// we really only care about the top revision bits here
rev &= ~((1 << 28)-1);
// increment revision
rev += 1 << 28;
#ifdef LFS_REVDBG
// include debug bits?
if (lfsr_m_isrevdbg(lfs->flags)) {
// mroot?
if (mdir->mid == -1 || lfsr_mdir_cmp(mdir, &lfs->mroot) == 0) {
rev |= 0x007e726d;
// mdir?
} else {
rev |= 0x007e646d;
}
}
#endif
#ifdef LFS_REVNOISE
// xor in pseudorandom noise
#ifdef LFS_NOISY
if (lfsr_m_isnoisy(lfs->flags)) {
if (lfsr_m_isrevnoise(lfs->flags)) {
rev ^= ((1 << (28-lfs_smax(lfs->recycle_bits, 0)))-1) & lfs->gcksum;
}
#endif
return rev;
}
// btrees don't normally need revision counts, but we make use of them
// if revdbg or revnoise is enabled
static inline uint32_t lfsr_rev_btree(lfs_t *lfs) {
(void)lfs;
uint32_t rev = 0;
#ifdef LFS_REVDBG
// include debug bits?
if (lfsr_m_isrevdbg(lfs->flags)) {
// mtree?
if (lfsr_i_isinmtree(lfs->flags)) {
rev |= 0x007e6d62;
// file btree?
} else {
rev |= 0x007e7462;
}
}
#endif
#ifdef LFS_REVNOISE
// xor in pseudorandom noise
if (lfsr_m_isrevnoise(lfs->flags)) {
// keep the top nibble zero
rev ^= 0x0fffffff & lfs->gcksum;
}
#endif
return rev;
}
static inline bool lfsr_rev_needsrelocation(lfs_t *lfs, uint32_t rev) {
if (lfs->recycle_bits == -1) {
return false;
@@ -7233,9 +7377,9 @@ static inline bool lfsr_rev_needsrelocation(lfs_t *lfs, uint32_t rev) {
static inline uint32_t lfsr_rev_inc(lfs_t *lfs, uint32_t rev) {
// increment recycle counter/revision
rev += 1 << (28-lfs_smax(lfs->recycle_bits, 0));
#ifdef LFS_REVNOISE
// xor in pseudorandom noise
#ifdef LFS_NOISY
if (lfsr_m_isnoisy(lfs->flags)) {
if (lfsr_m_isrevnoise(lfs->flags)) {
rev ^= ((1 << (28-lfs_smax(lfs->recycle_bits, 0)))-1) & lfs->gcksum;
}
#endif
@@ -7490,6 +7634,21 @@ static int lfsr_mtree_lookup(lfs_t *lfs, lfsr_smid_t mid, lfsr_tag_t tag,
return 0;
}
// this is the same as lfsr_btree_commit, but we set the inmtree flag
// for debugging reasons
static int lfsr_mtree_commit(lfs_t *lfs, lfsr_btree_t *mtree,
lfsr_bid_t bid, const lfsr_rattr_t *rattrs, lfs_size_t rattr_count) {
#ifdef LFS_REVDBG
lfs->flags |= LFS_i_INMTREE;
#endif
int err = lfsr_btree_commit(lfs, mtree, bid, rattrs, rattr_count);
#ifdef LFS_REVDBG
lfs->flags &= ~LFS_i_INMTREE;
#endif
return err;
}
/// Mdir commit logic ///
@@ -7531,7 +7690,7 @@ static int lfsr_mdir_alloc__(lfs_t *lfs, lfsr_mdir_t *mdir,
// note we allow corrupt errors here, as long as they are consistent
rev = (err != LFS_ERR_CORRUPT) ? lfs_fromle32_(&rev) : 0;
// reset recycle bits in revision count and increment
rev = lfsr_rev_init(lfs, rev);
rev = lfsr_rev_init(lfs, mdir, rev);
relocate:;
// allocate another block with an erase
@@ -8475,7 +8634,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
if (lfs->mtree.weight == 0) {
lfsr_btree_init(&mtree_);
err = lfsr_btree_commit(lfs, &mtree_,
err = lfsr_mtree_commit(lfs, &mtree_,
0, LFSR_RATTRS(
LFSR_RATTR_MPTR(
LFSR_TAG_MDIR, +(1 << lfs->mbits),
@@ -8495,7 +8654,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
// mark as unerased in case of failure
lfs->mtree.eoff = -1;
err = lfsr_btree_commit(lfs, &mtree_,
err = lfsr_mtree_commit(lfs, &mtree_,
lfsr_mbid(lfs, mdir->mid), LFSR_RATTRS(
LFSR_RATTR_MPTR(
LFSR_TAG_MDIR, 0,
@@ -8535,7 +8694,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
lfs->mtree.eoff = -1;
// update our mtree
err = lfsr_btree_commit(lfs, &mtree_,
err = lfsr_mtree_commit(lfs, &mtree_,
lfsr_mbid(lfs, mdir->mid), LFSR_RATTRS(
LFSR_RATTR(
LFSR_TAG_RM, -(1 << lfs->mbits))));
@@ -8557,7 +8716,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
if (lfs->mtree.weight == 0) {
lfsr_btree_init(&mtree_);
err = lfsr_btree_commit(lfs, &mtree_,
err = lfsr_mtree_commit(lfs, &mtree_,
0, LFSR_RATTRS(
LFSR_RATTR_MPTR(
LFSR_TAG_MDIR, +(1 << lfs->mbits),
@@ -8571,7 +8730,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
// mark as unerased in case of failure
lfs->mtree.eoff = -1;
err = lfsr_btree_commit(lfs, &mtree_,
err = lfsr_mtree_commit(lfs, &mtree_,
lfsr_mbid(lfs, mdir->mid), LFSR_RATTRS(
LFSR_RATTR_MPTR(
LFSR_TAG_MDIR, 0,
@@ -13027,11 +13186,16 @@ static int lfs_init(lfs_t *lfs, uint32_t flags,
| LFS_M_RDONLY
| LFS_M_FLUSH
| LFS_M_SYNC
| LFS_IFDEF_NOISY(LFS_M_NOISY, 0)
| LFS_IFDEF_REVDBG(LFS_M_REVDBG, 0)
| LFS_IFDEF_REVNOISE(LFS_M_REVNOISE, 0)
| LFS_IFDEF_CKPROGS(LFS_M_CKPROGS, 0)
| LFS_IFDEF_CKFETCHES(LFS_M_CKFETCHES, 0)
| LFS_IFDEF_CKPARITY(LFS_M_CKPARITY, 0)
| LFS_IFDEF_CKDATACKSUMS(LFS_M_CKDATACKSUMS, 0))) == 0);
#if defined(LFS_REVNOISE) && defined(LFS_REVDBG)
// LFS_M_REVDBG and LFS_M_REVNOISE are incompatible
LFS_ASSERT(!lfsr_m_isrevdbg(flags) || !lfsr_m_isrevnoise(flags));
#endif
// TODO this all needs to be cleaned up
lfs->cfg = cfg;
@@ -13845,7 +14009,8 @@ int lfsr_mount(lfs_t *lfs, uint32_t flags,
| LFS_M_RDONLY
| LFS_M_FLUSH
| LFS_M_SYNC
| LFS_IFDEF_NOISY(LFS_M_NOISY, 0)
| LFS_IFDEF_REVDBG(LFS_M_REVDBG, 0)
| LFS_IFDEF_REVNOISE(LFS_M_REVNOISE, 0)
| LFS_IFDEF_CKPROGS(LFS_M_CKPROGS, 0)
| LFS_IFDEF_CKFETCHES(LFS_M_CKFETCHES, 0)
| LFS_IFDEF_CKPARITY(LFS_M_CKPARITY, 0)
@@ -13866,7 +14031,8 @@ int lfsr_mount(lfs_t *lfs, uint32_t flags,
| LFS_M_RDONLY
| LFS_M_FLUSH
| LFS_M_SYNC
| LFS_IFDEF_NOISY(LFS_M_NOISY, 0)
| LFS_IFDEF_REVDBG(LFS_M_REVDBG, 0)
| LFS_IFDEF_REVNOISE(LFS_M_REVNOISE, 0)
| LFS_IFDEF_CKPROGS(LFS_M_CKPROGS, 0)
| LFS_IFDEF_CKFETCHES(LFS_M_CKFETCHES, 0)
| LFS_IFDEF_CKPARITY(LFS_M_CKPARITY, 0)
@@ -14029,7 +14195,8 @@ int lfsr_format(lfs_t *lfs, uint32_t flags,
// unknown flags?
LFS_ASSERT((flags & ~(
LFS_F_RDWR
| LFS_IFDEF_NOISY(LFS_F_NOISY, 0)
| LFS_IFDEF_REVDBG(LFS_F_REVDBG, 0)
| LFS_IFDEF_REVNOISE(LFS_F_REVNOISE, 0)
| LFS_IFDEF_CKPROGS(LFS_F_CKPROGS, 0)
| LFS_IFDEF_CKFETCHES(LFS_F_CKFETCHES, 0)
| LFS_IFDEF_CKPARITY(LFS_F_CKPARITY, 0)
@@ -14040,7 +14207,8 @@ int lfsr_format(lfs_t *lfs, uint32_t flags,
int err = lfs_init(lfs,
flags & (
LFS_F_RDWR
| LFS_IFDEF_NOISY(LFS_F_NOISY, 0)
| LFS_IFDEF_REVDBG(LFS_F_REVDBG, 0)
| LFS_IFDEF_REVNOISE(LFS_F_REVNOISE, 0)
| LFS_IFDEF_CKPROGS(LFS_F_CKPROGS, 0)
| LFS_IFDEF_CKFETCHES(LFS_F_CKFETCHES, 0)
| LFS_IFDEF_CKPARITY(LFS_F_CKPARITY, 0)
@@ -14100,7 +14268,8 @@ int lfsr_fs_stat(lfs_t *lfs, struct lfs_fsinfo *fsinfo) {
LFS_I_RDONLY
| LFS_I_FLUSH
| LFS_I_SYNC
| LFS_IFDEF_NOISY(LFS_I_NOISY, 0)
| LFS_IFDEF_REVDBG(LFS_I_REVDBG, 0)
| LFS_IFDEF_REVNOISE(LFS_I_REVNOISE, 0)
| LFS_IFDEF_CKPROGS(LFS_I_CKPROGS, 0)
| LFS_IFDEF_CKFETCHES(LFS_I_CKFETCHES, 0)
| LFS_IFDEF_CKPARITY(LFS_I_CKPARITY, 0)