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Flattened lfs3_file_crystallize_

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We no longer need to discard the leaf, since we can just leave ungrafted
leaves around as long as LFS3_o_UNGRAFT is set.

This let's us flatten lfs3_file_crystallize_, saving a bit of code and
cleaning up the logic a bit:

           code          stack          ctx
  before: 37032           2352          684
  after:  36992 (-0.1%)   2352 (+0.0%)  684 (+0.0%)

Note that lfs3_file_crystallize_ is still NOINLINE to force it off the
stack hot-path in lfs3_file_flush_, etc.
This commit is contained in:
Christopher Haster
2025-08-04 15:49:06 -05:00
parent 58c5506e85
commit 15c3d2f87a
1 changed files with 1 additions and 50 deletions
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lfs3.c
+1 -50
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@@ -13432,7 +13432,7 @@ static int lfs3_file_graft(lfs3_t *lfs3, lfs3_file_t *file) {
// this LFS3_NOINLINE is to force lfs3_file_crystallize__ off the stack // this LFS3_NOINLINE is to force lfs3_file_crystallize__ off the stack
// hot-path // hot-path
LFS3_NOINLINE LFS3_NOINLINE
static int lfs3_file_crystallize__(lfs3_t *lfs3, lfs3_file_t *file, static int lfs3_file_crystallize_(lfs3_t *lfs3, lfs3_file_t *file,
lfs3_off_t block_pos, lfs3_off_t block_pos,
lfs3_ssize_t crystal_min, lfs3_ssize_t crystal_max, lfs3_ssize_t crystal_min, lfs3_ssize_t crystal_max,
lfs3_off_t pos, const uint8_t *buffer, lfs3_size_t size) { lfs3_off_t pos, const uint8_t *buffer, lfs3_size_t size) {
@@ -13672,55 +13672,6 @@ static int lfs3_file_crystallize__(lfs3_t *lfs3, lfs3_file_t *file,
} }
#endif #endif
// note the slightly unique behavior when crystal_min=-1:
// - crystal_min=-1 => crystal_min=crystal_max
// - crystal_max=-1 => crystal_max=unbounded
//
// this helps avoid duplicate arguments with tight crystal bounds, if
// you really want to crystallize as little as possible, use
// crystal_min=0
//
// TODO flatten?
//
#if !defined(LFS3_RDONLY) && !defined(LFS3_KVONLY) && !defined(LFS3_2BONLY)
static int lfs3_file_crystallize_(lfs3_t *lfs3, lfs3_file_t *file,
lfs3_off_t block_pos,
lfs3_ssize_t crystal_min, lfs3_ssize_t crystal_max,
lfs3_off_t pos, const uint8_t *buffer, lfs3_size_t size) {
// this is split into two functions to try to minimize stack usage
// crystallize
int err = lfs3_file_crystallize__(lfs3, file,
block_pos, crystal_min, crystal_max,
pos, buffer, size);
if (err) {
goto failed;
}
// // if we fully crystallized, eagerly graft into the tree
// if (!lfs3_o_isuncryst(file->b.h.flags)) {
// err = lfs3_file_graft_(lfs3, file,
// file->leaf.pos, file->leaf.weight, 0,
// &file->leaf.bptr.d, LFS3_GRAFT_ISBPTR | 1);
// if (err) {
// goto failed;
// }
//
// // mark as grafted
// file->b.h.flags &= ~LFS3_o_UNGRAFT;
// }
return 0;
failed:;
// if we failed to crystallize we need to discard the leaf as it no
// longer matches the btree/bshrub state, this also clears the
// LFS3_o_UNCRYST and LFS3_o_UNGRAFT flags
lfs3_file_discardleaf(file);
return err;
}
#endif
#if !defined(LFS3_RDONLY) && !defined(LFS3_KVONLY) && !defined(LFS3_2BONLY) #if !defined(LFS3_RDONLY) && !defined(LFS3_KVONLY) && !defined(LFS3_2BONLY)
static int lfs3_file_crystallize(lfs3_t *lfs3, lfs3_file_t *file) { static int lfs3_file_crystallize(lfs3_t *lfs3, lfs3_file_t *file) {
// do nothing if our file is already crystallized // do nothing if our file is already crystallized