Some forms of storage, mainly anything with an FTL, eMMC, SD, etc, do
not guarantee a strict write order for writes to different blocks. It
would be good to test that this doesn't break littlefs.
This adds LFS_EMUBD_POWERLOSS_OOO to lfs_emubd, which tells lfs_emubd to
try to break any order-dependent code on powerloss.
The behavior right now is a bit simple, but does result in test
breakage:
1. Save the state of the block on first write (erase really) after
sync/init.
2. On powerloss, revert the first write to its original state.
This might be a bit confusing when debugging, since the block will
appear to time-travel, but doing anything fancier would make emubd quite
a bit more complicated.
You could also get a bit fancier with which/how many blocks to revert,
but this should at least be sufficient to make sure bd sync calls are in
the right place.
These are really just different flavors of test.py and test_runner.c
without support for power-loss testing, but with support for measuring
the cumulative number of bytes read, programmed, and erased.
Note that the existing define parameterization should work perfectly
fine for running benchmarks across various dimensions:
./scripts/bench.py \
runners/bench_runner \
bench_file_read \
-gnor \
-DSIZE='range(0,131072,1024)'
Also added a couple basic benchmarks as a starting point.
The main benefit is small test ids everywhere, though this is with the
downside of needing longer names to properly prefix and avoid
collisions. But this fits into the rest of the scripts with globally
unique names a bit better. This is a C project after all.
The other small benefit is test generators may have an easier time since
per-case symbols can expect to be unique.
This is really more work for the bench runner. With this change defines
can be manipulated at a rather high level at runtime. Which should be
useful for generating benchmarks across various dimensions.
The define grammar in the test_runner is now a bit more powerful,
accepting:
1. A single value: -DN=42
2. A list of values, which get permuted: -DN=1,2,3
3. A range: -DN=range(10)
4. Some combo: -DN=1,2,range(3,0,-1)
This is more complex in the test .toml defines, which can also be C
expressions:
1. A single value: define=42
2. A single expression: define='42*42'
3. A list: define=[1,2,3]
4. A comma separated string: define='1,2,3'
5. A range: define='42*range(10)'
6. This mess: define=[1,2,'3,4,range(2)*range(2)+3']
This mostly required names for each test case, declarations of
previously-implicit variables since the new test framework is more
conservative with what it declares (the small extra effort to add
declarations is well worth the simplicity and improved readability),
and tweaks to work with not-really-constant defines.
Also renamed test_ -> test, replacing the old ./scripts/test.py,
unfortunately git seems to have had a hard time with this.
Moved .travis.yml over to use the new test framework. A part of this
involved testing all of the configurations ran on the old framework
and deciding which to carry over. The new framework duplicates some of
the cases tested by the configurations so some configurations could be
dropped.
The .travis.yml includes some extreme ones, such as no inline files,
relocations every cycle, no intrinsics, power-loss every byte, unaligned
block_count and lookahead, and odd read_sizes.
There were several configurations were some tests failed because of
limitations in the tests themselves, so many conditions were added
to make sure the configurations can run on as many tests as possible.
- Removed old tests and test scripts
- Reorganize the block devices to live under one directory
- Plugged new test framework into Makefile
renamed:
- scripts/test_.py -> scripts/test.py
- tests_ -> tests
- {file,ram,test}bd/* -> bd/*
It took a surprising amount of effort to make the Makefile behave since
it turns out the "test_%" rule could override "tests/test_%.toml.test"
which is generated as part of test.py.
Christopher Haster