Github/littlefs
1
Fork 0
Code Actions Activity

Fixed explicit trunks messing with canonical checksums

Browse Source 
Updating the canonical checksum should only depend on if the tag is a
trunkish tag (not a checksum tag), and not if the tag is in the current
trunk. The trunk parameter to lfsr_rbyd_fetch should have no effect on
the canonical checksum.

Fixed in boath lfsr_rbyd_fetch and scripts.

Curiously no code changes:

           code          stack
  before: 36416           2616
  after:  36416 (+0.0%)   2616 (+0.0%
This commit is contained in:
Christopher Haster
2024-08-20 01:26:32 -05:00
parent 2f11fa71f4
commit c00e0b2af6
6 changed files with 167 additions and 159 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lfs.c
+34 -32
View File
@@ -3066,40 +3066,42 @@ static int lfsr_rbyd_fetch(lfs_t *lfs, lfsr_rbyd_t *rbyd,
} }
} }
// found a trunk of a tree? // found a trunk?
if (lfsr_tag_istrunk(tag) if (lfsr_tag_istrunk(tag)) {
&& (!trunk || off <= trunk || trunk__)) { if (!(trunk && off > trunk && !trunk__)) {
// start of trunk? // start of trunk?
if (!trunk__) { if (!trunk__) {
// keep track of trunk's entry point // keep track of trunk's entry point
trunk__ = off; trunk__ = off;
// reset weight // reset weight
weight_ = 0; weight_ = 0;
} }
// derive weight of the tree from alt pointers // derive weight of the tree from alt pointers
// //
// NOTE we can't check for overflow/underflow here because we // NOTE we can't check for overflow/underflow here because we
// may be overeagerly parsing an invalid commit, it's ok for // may be overeagerly parsing an invalid commit, it's ok for
// this to overflow/underflow as long as we throw it out later // this to overflow/underflow as long as we throw it out later
// on a bad cksum // on a bad cksum
weight_ += weight__; weight_ += weight__;
// end of trunk? // end of trunk?
if (!lfsr_tag_isalt(tag)) { if (!lfsr_tag_isalt(tag)) {
// update canonical checksum, xoring out any perturb // update trunk and weight, unless we are a shrub trunk
// state, we don't want erased-state affecting our if (!lfsr_tag_isshrub(tag) || trunk__ == trunk) {
// canonical checksum trunk_ = trunk__;
cksum = cksum_ ^ ((lfsr_rbyd_isperturb(rbyd)) weight = weight_;
? LFS_CRC32C_ODDZERO }
: LFS_CRC32C_EVENZERO); trunk__ = 0;
// update trunk and weight, unless we are a shrub trunk
if (!lfsr_tag_isshrub(tag) || trunk__ == trunk) {
trunk_ = trunk__;
weight = weight_;
} }
trunk__ = 0;
} }
// update canonical checksum, xoring out any perturb
// state, we don't want erased-state affecting our
// canonical checksum
cksum = cksum_ ^ ((lfsr_rbyd_isperturb(rbyd))
? LFS_CRC32C_ODDZERO
: LFS_CRC32C_EVENZERO);
} }
// skip data // skip data
scripts/dbgbmap.py
+26 -25
View File
@@ -695,33 +695,34 @@ class Rbyd:
cksum__ = cksum_ ^ (0xfca42daf if perturb else 0) cksum__ = cksum_ ^ (0xfca42daf if perturb else 0)
# evaluate trunks # evaluate trunks
if (tag & 0xf000) != TAG_CKSUM and ( if (tag & 0xf000) != TAG_CKSUM:
not trunk or j_-d <= trunk or trunk___): if not (trunk and j_-d > trunk and not trunk___):
# new trunk? # new trunk?
if not trunk___: if not trunk___:
trunk___ = j_-d trunk___ = j_-d
weight__ = 0 weight__ = 0
# keep track of weight # keep track of weight
weight__ += w weight__ += w
# end of trunk? # end of trunk?
if not tag & TAG_ALT: if not tag & TAG_ALT:
# update canonical checksum, xoring out any perturb state # update trunk/weight unless we found a shrub or an
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0) # explicit trunk (which may be a shrub) is requested
# update trunk/weight unless we found a shrub or an if not tag & TAG_SHRUB or trunk___ == trunk:
# explicit trunk (which may be a shrub) is requested trunk__ = trunk___
if not tag & TAG_SHRUB or trunk___ == trunk: weight_ = weight__
trunk__ = trunk___ # keep track of eoff for best matching trunk
weight_ = weight__ if trunk and j_ + size > trunk:
# keep track of eoff for best matching trunk eoff_ = j_ + size
if trunk and j_ + size > trunk: eoff = eoff_
eoff_ = j_ + size cksum = cksum_
eoff = eoff_ trunk_ = trunk__
cksum = cksum_ weight = weight_
trunk_ = trunk__ trunk___ = 0
weight = weight_
trunk___ = 0 # update canonical checksum, xoring out any perturb state
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0)
if not tag & TAG_ALT: if not tag & TAG_ALT:
j_ += size j_ += size
scripts/dbgbtree.py
+26 -25
View File
@@ -368,33 +368,34 @@ class Rbyd:
cksum__ = cksum_ ^ (0xfca42daf if perturb else 0) cksum__ = cksum_ ^ (0xfca42daf if perturb else 0)
# evaluate trunks # evaluate trunks
if (tag & 0xf000) != TAG_CKSUM and ( if (tag & 0xf000) != TAG_CKSUM:
not trunk or j_-d <= trunk or trunk___): if not (trunk and j_-d > trunk and not trunk___):
# new trunk? # new trunk?
if not trunk___: if not trunk___:
trunk___ = j_-d trunk___ = j_-d
weight__ = 0 weight__ = 0
# keep track of weight # keep track of weight
weight__ += w weight__ += w
# end of trunk? # end of trunk?
if not tag & TAG_ALT: if not tag & TAG_ALT:
# update canonical checksum, xoring out any perturb state # update trunk/weight unless we found a shrub or an
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0) # explicit trunk (which may be a shrub) is requested
# update trunk/weight unless we found a shrub or an if not tag & TAG_SHRUB or trunk___ == trunk:
# explicit trunk (which may be a shrub) is requested trunk__ = trunk___
if not tag & TAG_SHRUB or trunk___ == trunk: weight_ = weight__
trunk__ = trunk___ # keep track of eoff for best matching trunk
weight_ = weight__ if trunk and j_ + size > trunk:
# keep track of eoff for best matching trunk eoff_ = j_ + size
if trunk and j_ + size > trunk: eoff = eoff_
eoff_ = j_ + size cksum = cksum_
eoff = eoff_ trunk_ = trunk__
cksum = cksum_ weight = weight_
trunk_ = trunk__ trunk___ = 0
weight = weight_
trunk___ = 0 # update canonical checksum, xoring out any perturb state
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0)
if not tag & TAG_ALT: if not tag & TAG_ALT:
j_ += size j_ += size
scripts/dbglfs.py
+26 -25
View File
@@ -399,33 +399,34 @@ class Rbyd:
cksum__ = cksum_ ^ (0xfca42daf if perturb else 0) cksum__ = cksum_ ^ (0xfca42daf if perturb else 0)
# evaluate trunks # evaluate trunks
if (tag & 0xf000) != TAG_CKSUM and ( if (tag & 0xf000) != TAG_CKSUM:
not trunk or j_-d <= trunk or trunk___): if not (trunk and j_-d > trunk and not trunk___):
# new trunk? # new trunk?
if not trunk___: if not trunk___:
trunk___ = j_-d trunk___ = j_-d
weight__ = 0 weight__ = 0
# keep track of weight # keep track of weight
weight__ += w weight__ += w
# end of trunk? # end of trunk?
if not tag & TAG_ALT: if not tag & TAG_ALT:
# update canonical checksum, xoring out any perturb state # update trunk/weight unless we found a shrub or an
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0) # explicit trunk (which may be a shrub) is requested
# update trunk/weight unless we found a shrub or an if not tag & TAG_SHRUB or trunk___ == trunk:
# explicit trunk (which may be a shrub) is requested trunk__ = trunk___
if not tag & TAG_SHRUB or trunk___ == trunk: weight_ = weight__
trunk__ = trunk___ # keep track of eoff for best matching trunk
weight_ = weight__ if trunk and j_ + size > trunk:
# keep track of eoff for best matching trunk eoff_ = j_ + size
if trunk and j_ + size > trunk: eoff = eoff_
eoff_ = j_ + size cksum = cksum_
eoff = eoff_ trunk_ = trunk__
cksum = cksum_ weight = weight_
trunk_ = trunk__ trunk___ = 0
weight = weight_
trunk___ = 0 # update canonical checksum, xoring out any perturb state
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0)
if not tag & TAG_ALT: if not tag & TAG_ALT:
j_ += size j_ += size
scripts/dbgmtree.py
+26 -25
View File
@@ -383,33 +383,34 @@ class Rbyd:
cksum__ = cksum_ ^ (0xfca42daf if perturb else 0) cksum__ = cksum_ ^ (0xfca42daf if perturb else 0)
# evaluate trunks # evaluate trunks
if (tag & 0xf000) != TAG_CKSUM and ( if (tag & 0xf000) != TAG_CKSUM:
not trunk or j_-d <= trunk or trunk___): if not (trunk and j_-d > trunk and not trunk___):
# new trunk? # new trunk?
if not trunk___: if not trunk___:
trunk___ = j_-d trunk___ = j_-d
weight__ = 0 weight__ = 0
# keep track of weight # keep track of weight
weight__ += w weight__ += w
# end of trunk? # end of trunk?
if not tag & TAG_ALT: if not tag & TAG_ALT:
# update canonical checksum, xoring out any perturb state # update trunk/weight unless we found a shrub or an
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0) # explicit trunk (which may be a shrub) is requested
# update trunk/weight unless we found a shrub or an if not tag & TAG_SHRUB or trunk___ == trunk:
# explicit trunk (which may be a shrub) is requested trunk__ = trunk___
if not tag & TAG_SHRUB or trunk___ == trunk: weight_ = weight__
trunk__ = trunk___ # keep track of eoff for best matching trunk
weight_ = weight__ if trunk and j_ + size > trunk:
# keep track of eoff for best matching trunk eoff_ = j_ + size
if trunk and j_ + size > trunk: eoff = eoff_
eoff_ = j_ + size cksum = cksum_
eoff = eoff_ trunk_ = trunk__
cksum = cksum_ weight = weight_
trunk_ = trunk__ trunk___ = 0
weight = weight_
trunk___ = 0 # update canonical checksum, xoring out any perturb state
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0)
if not tag & TAG_ALT: if not tag & TAG_ALT:
j_ += size j_ += size
scripts/dbgrbyd.py
+29 -27
View File
@@ -577,12 +577,13 @@ def dbg_log(data, block_size, rev, eoff, weight, *,
# end of trunk? # end of trunk?
if not tag & TAG_ALT: if not tag & TAG_ALT:
# update canonical checksum, xoring out any perturb state
cksum = cksum_ ^ (0xfca42daf if perturb else 0)
# derive the current tag's rid from alt weights # derive the current tag's rid from alt weights
rid = lower_ + w-1 rid = lower_ + w-1
trunk_ = 0 trunk_ = 0
# update canonical checksum, xoring out any perturb state
cksum = cksum_ ^ (0xfca42daf if perturb else 0)
# show human-readable tag representation # show human-readable tag representation
print('%s%08x:%s %*s%s%*s %-*s%s%s%s' % ( print('%s%08x:%s %*s%s%*s %-*s%s%s%s' % (
'\x1b[90m' if color and j >= eoff else '', '\x1b[90m' if color and j >= eoff else '',
@@ -976,33 +977,34 @@ def main(disk, blocks=None, *,
cksum__ = cksum_ ^ (0xfca42daf if perturb else 0) cksum__ = cksum_ ^ (0xfca42daf if perturb else 0)
# evaluate trunks # evaluate trunks
if (tag & 0xf000) != TAG_CKSUM and ( if (tag & 0xf000) != TAG_CKSUM:
not trunk or j_-d <= trunk or trunk___): if not (trunk and j_-d > trunk and not trunk___):
# new trunk? # new trunk?
if not trunk___: if not trunk___:
trunk___ = j_-d trunk___ = j_-d
weight__ = 0 weight__ = 0
# keep track of weight # keep track of weight
weight__ += w weight__ += w
# end of trunk? # end of trunk?
if not tag & TAG_ALT: if not tag & TAG_ALT:
# update canonical checksum, xoring out any perturb state # update trunk/weight unless we found a shrub or an
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0) # explicit trunk (which may be a shrub) is requested
# update trunk/weight unless we found a shrub or an if not tag & TAG_SHRUB or trunk___ == trunk:
# explicit trunk (which may be a shrub) is requested trunk__ = trunk___
if not tag & TAG_SHRUB or trunk___ == trunk: weight_ = weight__
trunk__ = trunk___ # keep track of eoff for best matching trunk
weight_ = weight__ if trunk and j_ + size > trunk:
# keep track of eoff for best matching trunk eoff_ = j_ + size
if trunk and j_ + size > trunk: eoff = eoff_
eoff_ = j_ + size cksum = cksum_
eoff = eoff_ trunk_ = trunk__
cksum = cksum_ weight = weight_
trunk_ = trunk__ trunk___ = 0
weight = weight_
trunk___ = 0 # update canonical checksum, xoring out any perturb state
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0)
if not tag & TAG_ALT: if not tag & TAG_ALT:
j_ += size j_ += size