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Moved ckreads behind the LFS_M_CKREADS flag

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Added some code, though we don't _really_ care:

           code          stack
  before: 37872           3048
  after:  38060 (+0.5%)   3056 (+0.3%)

Also interesting to note the difference in testing time, this highlights
_some_ of the performance cost of ckreads:

  with ckreads:    1135.92s
  without ckreads:  821.24s
This commit is contained in:
Christopher Haster
2024-08-10 23:29:54 -05:00
parent 458fe16f38
commit 185f209dbf
4 changed files with 89 additions and 16 deletions
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lfs.c
+76 -8
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@@ -868,7 +868,7 @@ static int lfsr_bd_cksuffix(lfs_t *lfs,
// contributes to the relevant parity/checksum, this may be
// significantly more than the data we actually end up using
//
static int lfsr_bd_readck(lfs_t *lfs,
static int lfsr_bd_readck_(lfs_t *lfs,
lfs_block_t block, lfs_size_t off, lfs_size_t hint,
void *buffer, lfs_size_t size,
lfsr_ck_t ck) {
@@ -907,13 +907,33 @@ static int lfsr_bd_readck(lfs_t *lfs,
return 0;
}
// needed in lfsr_bd_readck
static inline bool lfsr_m_isckreads(uint32_t flags);
static int lfsr_bd_readck(lfs_t *lfs,
lfs_block_t block, lfs_size_t off, lfs_size_t hint,
void *buffer, lfs_size_t size,
lfsr_ck_t ck) {
// are we actually checking reads?
if (lfsr_m_isckreads(lfs->flags)) {
return lfsr_bd_readck_(lfs,
block, off, hint,
buffer, size,
ck);
} else {
return lfsr_bd_read(lfs,
block, off, hint,
buffer, size);
}
}
// these could probably be a bit better deduplicated with their
// unchecked counterparts, but we don't generally use both at the same
// time
//
// we'd also need to worry about early termination in lfsr_bd_cmp/cmpck
static lfs_scmp_t lfsr_bd_cmpck(lfs_t *lfs,
static lfs_scmp_t lfsr_bd_cmpck_(lfs_t *lfs,
lfs_block_t block, lfs_size_t off, lfs_size_t hint,
const void *buffer, lfs_size_t size,
lfsr_ck_t ck) {
@@ -972,7 +992,24 @@ static lfs_scmp_t lfsr_bd_cmpck(lfs_t *lfs,
return cmp;
}
static int lfsr_bd_cpyck(lfs_t *lfs,
static lfs_scmp_t lfsr_bd_cmpck(lfs_t *lfs,
lfs_block_t block, lfs_size_t off, lfs_size_t hint,
const void *buffer, lfs_size_t size,
lfsr_ck_t ck) {
// are we actually checking reads?
if (lfsr_m_isckreads(lfs->flags)) {
return lfsr_bd_cmpck_(lfs,
block, off, hint,
buffer, size,
ck);
} else {
return lfsr_bd_cmp(lfs,
block, off, hint,
buffer, size);
}
}
static int lfsr_bd_cpyck_(lfs_t *lfs,
lfs_block_t dst_block, lfs_size_t dst_off,
lfs_block_t src_block, lfs_size_t src_off, lfs_size_t hint,
lfs_size_t size,
@@ -1044,6 +1081,29 @@ static int lfsr_bd_cpyck(lfs_t *lfs,
return 0;
}
static int lfsr_bd_cpyck(lfs_t *lfs,
lfs_block_t dst_block, lfs_size_t dst_off,
lfs_block_t src_block, lfs_size_t src_off, lfs_size_t hint,
lfs_size_t size,
lfsr_ck_t ck,
uint32_t *cksum, bool align) {
// are we actually checking reads?
if (lfsr_m_isckreads(lfs->flags)) {
return lfsr_bd_cpyck_(lfs,
dst_block, dst_off,
src_block, src_off, hint,
size,
ck,
cksum, align);
} else {
return lfsr_bd_cpy(lfs,
dst_block, dst_off,
src_block, src_off, hint,
size,
cksum, align);
}
}
@@ -1563,12 +1623,14 @@ static lfs_ssize_t lfsr_bd_readtag(lfs_t *lfs,
*cksum ^= tag_buf[0] & 0x00000080;
// calculate checksum
*cksum = lfs_crc32c(*cksum, tag_buf, d);
}
// check the parity if we're not already calculating a checksum
// check the parity if we're checking reads and not already
// calculating a checksum
//
// this requires reading the data too, but with any luck the data
// will stick around in the cache
} else {
// this requires reading all of the data as well, but with any luck
// the data will stick around in the cache
if (lfsr_m_isckreads(lfs->flags) && !cksum) {
// pesky parity byte
lfs_size_t size__ = (!lfsr_tag_isalt(tag)) ? size : 0;
if (off+d+size__ >= lfs->cfg->block_size) {
@@ -6503,6 +6565,10 @@ static inline bool lfsr_m_isckprogs(uint32_t flags) {
return flags & LFS_M_CKPROGS;
}
static inline bool lfsr_m_isckreads(uint32_t flags) {
return flags & LFS_M_CKREADS;
}
static inline bool lfsr_m_isflush(uint32_t flags) {
return flags & LFS_M_FLUSH;
}
@@ -13118,6 +13184,7 @@ int lfsr_mount(lfs_t *lfs, uint32_t flags,
LFS_M_RDWR
| LFS_M_RDONLY
| LFS_M_CKPROGS
| LFS_M_CKREADS
| LFS_M_FLUSH
| LFS_M_SYNC
| LFS_M_MTREEONLY
@@ -13275,7 +13342,7 @@ static int lfsr_formatinited(lfs_t *lfs) {
int lfsr_format(lfs_t *lfs, const struct lfs_config *cfg) {
// TODO hmmm, should lfsr_format take flags?
int err = lfs_init(lfs, LFS_M_RDWR | LFS_M_CKPROGS, cfg);
int err = lfs_init(lfs, LFS_M_RDWR | LFS_M_CKPROGS | LFS_M_CKREADS, cfg);
if (err) {
return err;
}
@@ -13306,6 +13373,7 @@ int lfsr_fs_stat(lfs_t *lfs, struct lfs_fsinfo *fsinfo) {
fsinfo->flags = lfs->flags & (
LFS_I_RDONLY
| LFS_I_CKPROGS
| LFS_I_CKREADS
| LFS_I_FLUSH
| LFS_I_SYNC
| LFS_I_UNCOMPACTED);