Github/littlefs
1
Fork 0
Code Actions Activity

Cleaned up data concatenation when fragment coalescing

Browse Source 
Basically we now assume we will also concatenate data, even if there is
only a single data. But stack cost is worst-case anyways, so this
doesn't have any tangible downside.

           code          stack
  before: 33944           2888
  after:  33868 (-0.2%)   2880 (-0.3%)
This commit is contained in:
Christopher Haster
2024-02-24 22:29:27 -06:00
parent d751f5462b
commit ef433f983c
1 changed files with 20 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lfs.c
+20 -20
View File
@@ -10424,7 +10424,7 @@ static int lfsr_file_flush_(lfs_t *lfs, lfsr_file_t *file,
if (crystal_end - crystal_start < lfs->cfg->crystal_thresh
// enough for prog alignment?
|| crystal_end - crystal_start < lfs->cfg->prog_size) {
break;
goto fragment;
}
// exceeded our crystallization threshold? compact into a new block
@@ -10685,19 +10685,17 @@ static int lfsr_file_flush_(lfs_t *lfs, lfsr_file_t *file,
aligned = true;
}
fragment:;
// iteratively write fragments (inlined leaves)
while (size > 0) {
// truncate to our fragment size
lfs_off_t fragment_start = pos;
lfs_off_t fragment_end = fragment_start
+ lfs_min32(size, lfs->cfg->fragment_size);
lfsr_data_t data = LFSR_DATA_BUF(
buffer,
fragment_end - fragment_start);
lfs_off_t fragment_end = fragment_start + lfs_min32(
size,
lfs->cfg->fragment_size);
lfsr_data_t datas[3];
lfs_size_t data_count = 0;
datas[data_count++] = data;
// do we have a left sibling?
if (fragment_start > 0
@@ -10720,22 +10718,21 @@ static int lfsr_file_flush_(lfs_t *lfs, lfsr_file_t *file,
if (bid-(weight-1) + lfsr_data_size(bptr.data) >= fragment_start
&& fragment_end - (bid-(weight-1))
<= lfs->cfg->fragment_size) {
// coalesce, but truncate to our fragment size
// TODO this is a bit of a hacky way to prepend data...
LFS_ASSERT(data_count == 1);
datas[0] = lfsr_data_truncate(bptr.data,
datas[data_count++] = lfsr_data_truncate(bptr.data,
fragment_start - (bid-(weight-1)));
datas[1] = lfsr_data_truncate(data,
lfs->cfg->fragment_size
- (fragment_start - (bid-(weight-1))));
data_count = 2;
data = lfsr_data_fromcat(datas, data_count);
fragment_start = bid-(weight-1);
fragment_end = fragment_start + lfsr_data_size(data);
fragment_end = fragment_start + lfs_min32(
fragment_end - (bid-(weight-1)),
lfs->cfg->fragment_size);
}
}
// append our new data
datas[data_count++] = LFSR_DATA_BUF(
buffer,
fragment_end - pos);
// do we have a right sibling?
//
// note this may the same as our left sibling
@@ -10762,9 +10759,11 @@ static int lfsr_file_flush_(lfs_t *lfs, lfsr_file_t *file,
datas[data_count++] = lfsr_data_fruncate(bptr.data,
bid-(weight-1) + lfsr_data_size(bptr.data)
- fragment_end);
data = lfsr_data_fromcat(datas, data_count);
fragment_end = fragment_start + lfsr_data_size(data);
fragment_end = fragment_start + lfs_min32(
bid-(weight-1) + lfsr_data_size(bptr.data)
- fragment_start,
lfs->cfg->fragment_size);
}
}
@@ -10773,9 +10772,10 @@ static int lfsr_file_flush_(lfs_t *lfs, lfsr_file_t *file,
// once we've figured out what fragment to write, carve it into
// our tree
lfsr_data_t data = lfsr_data_fromcat(datas, data_count);
int err = lfsr_file_carve(lfs, file,
fragment_start, fragment_end - fragment_start, 0,
LFSR_TAG_DATA, &(const lfsr_bptr_t){.data=data}, NULL);
LFSR_TAG_DATA, (const lfsr_bptr_t*)&data, NULL);
if (err && err != LFS_ERR_RANGE) {
return err;
}