t: Switched back to mid-based traversal clobbering

Implementing gc_compact_thresh over bshrubs highlighted that it's really
not that difficult, and probably required, for traversal bshrubs to be
tracked correctly during mdir commits/compacts/splits/etc. And if we
track bshrubs across mdir commits, we might as well clobber traversals
at the mid level, allowing traversals to always reach btrees/bshrubs not
under active mutation.

One key thing to note: we should never be traversing a bshrub that is
not referenced elsewhere, either on-disk in an mdir or in-ram via an
opened file. So any compacted traversal bshrubs are not wasted prog
cycles.

This moves most of the clobbering logic back up into the high-level
functions (lfsr_remove/rename mainly), where we know which mids may be
clobbered.

This has a code cost, but it's really not all that much for more
thorough/correct filesystem traversals under mutation:

           code          stack
  before: 35268           2680
  after:  35368 (+0.3%)   2680 (+0.0%)

Unfortunately, lingering rbyd references in our btraversal structs are
still an issue, and some bshrub tests are failing... Though I do have
some ideas on how to fix this.
This commit is contained in:
Christopher Haster
2024-07-02 17:34:21 -05:00
parent 7f4384fa27
commit 7fdf0b7d23
2 changed files with 242 additions and 84 deletions
+196 -40
View File
@@ -1696,10 +1696,6 @@ code = '''
lfsr_file_open(&lfs, &file, "spider",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
lfsr_file_close(&lfs, &file) => 0;
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
goto done;
}
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
@@ -1716,7 +1712,6 @@ code = '''
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
done:;
lfsr_unmount(&lfs) => 0;
'''
@@ -1815,6 +1810,9 @@ code = '''
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
lfsr_file_close(&lfs, &file) => 0;
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
assert(tinfo.block == 0 || tinfo.block == 1);
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
@@ -1938,10 +1936,6 @@ code = '''
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_BUSY;
goto done;
}
struct lfs_tinfo tinfo;
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
goto done;
}
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
@@ -2016,10 +2010,6 @@ code = '''
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_BUSY;
goto done;
}
struct lfs_tinfo tinfo;
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
goto done;
}
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
@@ -2094,10 +2084,6 @@ code = '''
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_BUSY;
goto done;
}
struct lfs_tinfo tinfo;
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
goto done;
}
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
@@ -2428,6 +2414,14 @@ code = '''
lfsr_file_write(&lfs, &file, wbuf1, SIZE) => SIZE;
lfsr_file_close(&lfs, &file) => 0;
// traverse btree
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_BTREE);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -2509,6 +2503,11 @@ code = '''
lfsr_file_write(&lfs, &file, wbuf1, SIZE) => SIZE;
lfsr_file_close(&lfs, &file) => 0;
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -2754,6 +2753,11 @@ code = '''
}
lfsr_file_write(&lfs, &file1, wbuf1, SIZE) => SIZE;
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -2919,16 +2923,14 @@ code = '''
}
lfsr_file_close(&lfs, &file1) => 0;
if (DESYNC) {
// traverse btree
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_BTREE);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
}
// traverse btree
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_BTREE);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3013,13 +3015,11 @@ code = '''
}
lfsr_file_close(&lfs, &file1) => 0;
if (DESYNC) {
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
}
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3101,6 +3101,11 @@ code = '''
// remove the file
lfsr_remove(&lfs, "spider") => 0;
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3129,7 +3134,7 @@ code = '''
uint32_t prng = 42;
// create two files
// create three files
lfsr_file_t file;
lfsr_file_open(&lfs, &file, "spider",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
@@ -3149,6 +3154,15 @@ code = '''
lfsr_file_write(&lfs, &file, wbuf2, SIZE) => SIZE;
lfsr_file_close(&lfs, &file) => 0;
lfsr_file_open(&lfs, &file, "wolfspider",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
uint8_t wbuf3[SIZE];
for (lfs_size_t j = 0; j < SIZE; j++) {
wbuf3[j] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_write(&lfs, &file, wbuf3, SIZE) => SIZE;
lfsr_file_close(&lfs, &file) => 0;
// try traversing
lfsr_traversal_t t;
lfsr_traversal_open(&lfs, &t,
@@ -3171,6 +3185,16 @@ code = '''
// rename one file over another
lfsr_rename(&lfs, "spider", "tarantula") => 0;
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3184,6 +3208,11 @@ code = '''
assert(memcmp(rbuf, wbuf1, SIZE) == 0);
lfsr_file_close(&lfs, &file) => 0;
lfsr_file_open(&lfs, &file, "wolfspider", LFS_O_RDONLY) => 0;
lfsr_file_read(&lfs, &file, rbuf, SIZE) => SIZE;
assert(memcmp(rbuf, wbuf3, SIZE) == 0);
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
'''
@@ -3219,6 +3248,15 @@ code = '''
lfsr_file_write(&lfs, &file, wbuf2, SIZE) => SIZE;
lfsr_file_close(&lfs, &file) => 0;
lfsr_file_open(&lfs, &file, "wolfspider",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_EXCL) => 0;
uint8_t wbuf3[SIZE];
for (lfs_size_t j = 0; j < SIZE; j++) {
wbuf3[j] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_write(&lfs, &file, wbuf3, SIZE) => SIZE;
lfsr_file_close(&lfs, &file) => 0;
// try traversing
lfsr_traversal_t t;
lfsr_traversal_open(&lfs, &t,
@@ -3241,6 +3279,11 @@ code = '''
// rename one file over another
lfsr_rename(&lfs, "tarantula", "spider") => 0;
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3254,6 +3297,11 @@ code = '''
lfsr_file_open(&lfs, &file, "tarantula", LFS_O_RDONLY) => LFS_ERR_NOENT;
lfsr_file_open(&lfs, &file, "wolfspider", LFS_O_RDONLY) => 0;
lfsr_file_read(&lfs, &file, rbuf, SIZE) => SIZE;
assert(memcmp(rbuf, wbuf3, SIZE) == 0);
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
'''
@@ -3313,6 +3361,26 @@ code = '''
i += 1;
}
// traverse mdir
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse mdir
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3403,6 +3471,24 @@ code = '''
i += 1;
}
// traverse another data block
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse mdir
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3503,6 +3589,14 @@ code = '''
i += 1;
}
// traverse another data block
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3583,6 +3677,21 @@ code = '''
lfsr_remove(&lfs, "uloborus") => 0;
}
// traverse mroot
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3664,6 +3773,14 @@ code = '''
lfsr_remove(&lfs, "uloborus") => 0;
}
// traverse another data block
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -3863,6 +3980,14 @@ code = '''
lfsr_remove(&lfs, "uloborus") => 0;
}
// traverse another data block
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// we should be at end of traversal now
lfsr_traversal_read(&lfs, &t, &tinfo) => LFS_ERR_NOENT;
lfsr_traversal_close(&lfs, &t) => 0;
@@ -4169,7 +4294,20 @@ code = '''
i += 1;
}
// traverse untouched mdir
// traverse another data block
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse mdir
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse mdir
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
@@ -4333,8 +4471,10 @@ code = '''
lfsr_file_close(&lfs, &file) => 0;
i += 1;
}
// traverse untouched mdir
// traverse another data block
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse mdir
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
@@ -4661,7 +4801,15 @@ code = '''
lfsr_remove(&lfs, "vulsor") => 0;
}
// traverse untouched mdir
// traverse another data block
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse mdir
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
@@ -5004,7 +5152,15 @@ code = '''
lfsr_remove(&lfs, "vulsor") => 0;
}
// traverse untouched mdir
// traverse another data block
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse two data blocks
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_DATA);
// traverse mdir
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;
assert(tinfo.btype == LFS_BTYPE_MDIR);
lfsr_traversal_read(&lfs, &t, &tinfo) => 0;