It is no longer necessary to get good performance, there is only a small
speed difference between -O2 and -O3, so just stick to the default of
-O2. I've measured neutral compression speed and a ~3% decompression
speed loss in userspace with clang & gcc. I've also measured neutral
compression speed and a ~1% decompression speed loss in the kernel
benchmarks.
This also fixes the stack space usage on parisc. The compiler was buggy
for -O3 and used ~3KB of stack space for several functions. With -O2 the
problem is completely resolved, and stack space is back to a few hundred
bytes.
Additionally, we get a large code size win on gcc:
| Compiler | Before (Bytes) | After (Bytes) | Delta (Bytes) |
|----------|----------------|---------------|---------------|
| gcc-11 | 952754 | 738954 | -213800 |
| clang-12 | 976290 | 938826 | -37464 |
The optimal parser is unlikely to be used in the linux kernel in
practice. There is no reason these functions should be force inlined,
since we aren't gaining anything, and are losing build size.
| Compiler | Before (Bytes) | After (Bytes) | Delta (Bytes) |
|----------|----------------|---------------|---------------|
| gcc-11 | 1142090 | 952754 | -189336 |
| clang-12 | 1228402 | 976290 | -252112 |
This is a temporary solution pending the resolution of PR #2862 in the
`dev` branch.
Test the kernel build with the standard warnings enabled so that we
don't miss issues like fixed in PR #2802.
Stacked on top of PR #2802 so CI passes, so it includes the fix. But, I
won't merge until it is merged, so @solbjorn gets the credit for the
fix.
Switch to a macro `ZSTD_FALLTHROUGH;` instead of a comment. On supported
compilers this uses an attribute, otherwise it becomes a comment.
This is necessary to be compatible with clang's `-Wfall-through`, and
gcc's `-Wfall-through=2` which don't support comments. Without this the
linux build emits a bunch of warnings.
Also add a test to CI to ensure that we don't regress.
Commit a5f2c45528 ("Huffman ASM") added a new ASM source file,
but it wasn't added to the kernel Makefile despite that it received
support for Huffman ASM according to the internal definitions. This
leads to undefined references, as huf_decompress.o now calls those
ASM functions.
Add it to the list of sources when building inside the kernel tree.
Kbuild can handle .S files just fine, so none additional rules
needed.
Fixes: a5f2c45528 ("Huffman ASM")
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Linux 5.15 introduces a new Kconfig option, CONFIG_WERROR, which
forces -Werror for the entire kernel.
Current in-kernel ZSTD implementation uses functions deprecated
in 1.5.0, and thus fails on -Wdeprecated-declarations.
Turn this particular error into warning to be able to build the
kernel with CONFIG_WERROR. I'm not disabling them completely to
make sure they'll be visible and [hopefully] fixed sooner or later.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Instead of calling `ZSTD_compress_advanced()` and
`ZSTD_initCStream_advanced()`, which each take a `ZSTD_parameters` by
value, use the new advanced API.
Stack usage went from 2024 -> 1944.
* Extract out common portion of `lib/Makefile` into `lib/libzstd.mk`.
Most relevantly, the way we find library files.
* Use `lib/libzstd.mk` in the other Makefiles instead of repeating the
same code.
* Add a test `tests/test-variants.sh` that checks that the builds of
`make -C programs allVariants` are correct, and run it in Actions.
* Adds support for ASM files in the CMake build.
The Meson build is not updated because it lists every file in zstd,
and supports ASM off the bat, so the Huffman ASM commit will just add
the ASM file to the list.
The Visual Studios build is not updated because I'm not adding ASM
support to Visual Studios yet.
* seekable_format: fix from-file reading (not in-memory)
It tries to check the buffer boundary, but there is no buffer for
from-file reading.
* seekable_decompression: break when ZSTD_seekable_decompress() returns zero
* seekable_decompression_mem: break when ZSTD_seekable_decompress() returns zero
* seekable_format: cap the offset+len up to the last dOffset
This will allow to read the whole file w/o gotting corruption error if
the offset is more then the data left in file, i.e.:
$ ./seekable_compression seekable_compression.c 8192 | head
$ zstd -cdq seekable_compression.c.zst | wc -c
4737
Before this patch:
$ ./seekable_decompression seekable_compression.c.zst 0 10000000 | wc -c
ZSTD_seekable_decompress() error : Corrupted block detected
0
After:
$ ./seekable_decompression seekable_compression.c.zst 0 10000000 | wc -c
4737
`zstd_errors.h` and `zdict.h` are public headers, so they deserve to be
in the root `lib/` directory with `zstd.h`, not mixed in with our private
headers.
Replace kernel-style comments with regular comments.
E.g.
```
/** Before */
/* After */
/**
* Before
*/
/*
* After
*/
/***********************************
* Before
***********************************/
/* *********************************
* After
***********************************/
```
* Switch to yearless copyright per FB policy
* Fix up SPDX-License-Identifier lines in `contrib/linux-kernel` sources
* Add zstd copyright/license header to the `contrib/linux-kernel` sources
* Update the `tests/test-license.py` to check for yearless copyright
* Improvements to `tests/test-license.py`
* Check `contrib/linux-kernel` in `tests/test-license.py`
Expose the zstd headers in `include/linux` to avoid struct duplication.
This makes the member names not follow Kernel style guidelines, and
exposes the zstd symbols. But, the LMKL reviewers are okay with that.
These are replaced by the corresponding context resets. When
converting resetCStream, CCtx_setPledgedSrcSize isn't called if the
source size is "unknown".
This helps reduce the reliance on "static only" symbols, as well as
reducing the use of deprecated functions.
Signed-off-by: Stephen Kitt <steve@sk2.org>
