| Message ID | 20241021002935.325878-1-ebiggers@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | Wire up CRC32 library functions to arch-optimized code | expand |
On Mon, 21 Oct 2024 at 02:29, Eric Biggers <ebiggers@kernel.org> wrote: > > This patchset is also available in git via: > > git fetch https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git crc32-lib-v1 > > CRC32 is a family of common non-cryptographic integrity check algorithms > that are fairly fast with a portable C implementation and become far > faster still with the CRC32 or carryless multiplication instructions > that most CPUs have. 9 architectures already have optimized code for at > least some CRC32 variants; however, except for arm64 this optimized code > was only accessible through the crypto API, not the library functions. > > This patchset fixes that so that the CRC32 library functions use the > optimized code. This allows users to just use the library instead of > the crypto API. This is much simpler and also improves performance due > to eliminating the crypto API overhead including an indirect call. Some > examples of updating users are included at the end of the patchset. > > Note: crc32c() was a weird case. It was a library function layered on > top of the crypto API, which in turn is layered on top of the real > library functions. So while it was easy to use, it was still subject to > the crypto API overhead. This patchset provides CRC32C acceleration in > the real library functions directly. > > The updated CRC32 library design is: > > - Each arch's CRC32 code (all variants) is in arch/$ARCH/lib/crc32*. > This adopts what arm64 and riscv already did. Note, the crypto > directory is not used because CRC32 is not a cryptographic algorithm. > > - Weak symbols are no longer used. Instead there are crc32*_base() and > crc32*_arch(), and the appropriate ones are called based on the > kconfig. This is similar to how the ChaCha20 library code works. > > - Each arch's CRC32 code is enabled by default when CRC32 is enabled, > but it can now be disabled, controlled by the choice that previously > controlled the base implementation only. It can also now be built as > a module if CRC32 is a module too. > > - Instead of lots of pointless glue code that wires up each CRC32 > variant to the crypto API for each architecture, we now just rely on > the existing shash algorithms that use the library functions. > > - As before, the library functions don't provide access to off-CPU > crypto accelerators. But these appear to have very little, if any, > real-world relevance for CRC32 which is very fast on CPUs. > > Future work should apply a similar cleanup to crct10dif which is a > variant of CRC16. > > I tested all arches in QEMU using CONFIG_CRC32_SELFTEST and the crypto > self-tests, except for mips which I couldn't figure out how to do. > > This patchset has the following dependencies on recent patches: > > - "crypto - move crypto_simd_disabled_for_test to lib" > (https://lore.kernel.org/linux-crypto/20241018235343.425758-1-ebiggers@kernel.org/) > - "crypto: x86/crc32c - jump table elimination and other cleanups" > (https://lore.kernel.org/linux-crypto/20241014042447.50197-1-ebiggers@kernel.org/) > - "arm64: Speed up CRC-32 using PMULL instructions" > (https://lore.kernel.org/linux-crypto/20241018075347.2821102-5-ardb+git@google.com/) > - "crypto: Enable fuzz testing for arch code" > (https://lore.kernel.org/linux-crypto/20241016185722.400643-4-ardb+git@google.com/) > - "crypto: mips/crc32 - fix the CRC32C implementation" > (https://lore.kernel.org/linux-crypto/20241020180258.8060-1-ebiggers@kernel.org/) > > Everything can be retrieved from git using the command given earlier. > > Since this patchset touches many areas, getting it merged may be > difficult. One option is a pull request with the whole patchset > directly to Linus. Another is to have at least patches 1-2 and the > above dependencies taken through the crypto tree in v6.13; then the arch > patches can land separately afterwards, followed by the rest. > > Eric Biggers (15): > lib/crc32: drop leading underscores from __crc32c_le_base > lib/crc32: improve support for arch-specific overrides > arm/crc32: expose CRC32 functions through lib > loongarch/crc32: expose CRC32 functions through lib > mips/crc32: expose CRC32 functions through lib > powerpc/crc32: expose CRC32 functions through lib > s390/crc32: expose CRC32 functions through lib > sparc/crc32: expose CRC32 functions through lib > x86/crc32: update prototype for crc_pcl() > x86/crc32: update prototype for crc32_pclmul_le_16() > x86/crc32: expose CRC32 functions through lib > lib/crc32: make crc32c() go directly to lib > ext4: switch to using the crc32c library > jbd2: switch to using the crc32c library > f2fs: switch to using the crc32 library > ... > 89 files changed, 1002 insertions(+), 2455 deletions(-) Very nice cleanup! For the series: Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
This patchset is also available in git via: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git crc32-lib-v1 CRC32 is a family of common non-cryptographic integrity check algorithms that are fairly fast with a portable C implementation and become far faster still with the CRC32 or carryless multiplication instructions that most CPUs have. 9 architectures already have optimized code for at least some CRC32 variants; however, except for arm64 this optimized code was only accessible through the crypto API, not the library functions. This patchset fixes that so that the CRC32 library functions use the optimized code. This allows users to just use the library instead of the crypto API. This is much simpler and also improves performance due to eliminating the crypto API overhead including an indirect call. Some examples of updating users are included at the end of the patchset. Note: crc32c() was a weird case. It was a library function layered on top of the crypto API, which in turn is layered on top of the real library functions. So while it was easy to use, it was still subject to the crypto API overhead. This patchset provides CRC32C acceleration in the real library functions directly. The updated CRC32 library design is: - Each arch's CRC32 code (all variants) is in arch/$ARCH/lib/crc32*. This adopts what arm64 and riscv already did. Note, the crypto directory is not used because CRC32 is not a cryptographic algorithm. - Weak symbols are no longer used. Instead there are crc32*_base() and crc32*_arch(), and the appropriate ones are called based on the kconfig. This is similar to how the ChaCha20 library code works. - Each arch's CRC32 code is enabled by default when CRC32 is enabled, but it can now be disabled, controlled by the choice that previously controlled the base implementation only. It can also now be built as a module if CRC32 is a module too. - Instead of lots of pointless glue code that wires up each CRC32 variant to the crypto API for each architecture, we now just rely on the existing shash algorithms that use the library functions. - As before, the library functions don't provide access to off-CPU crypto accelerators. But these appear to have very little, if any, real-world relevance for CRC32 which is very fast on CPUs. Future work should apply a similar cleanup to crct10dif which is a variant of CRC16. I tested all arches in QEMU using CONFIG_CRC32_SELFTEST and the crypto self-tests, except for mips which I couldn't figure out how to do. This patchset has the following dependencies on recent patches: - "crypto - move crypto_simd_disabled_for_test to lib" (https://lore.kernel.org/linux-crypto/20241018235343.425758-1-ebiggers@kernel.org/) - "crypto: x86/crc32c - jump table elimination and other cleanups" (https://lore.kernel.org/linux-crypto/20241014042447.50197-1-ebiggers@kernel.org/) - "arm64: Speed up CRC-32 using PMULL instructions" (https://lore.kernel.org/linux-crypto/20241018075347.2821102-5-ardb+git@google.com/) - "crypto: Enable fuzz testing for arch code" (https://lore.kernel.org/linux-crypto/20241016185722.400643-4-ardb+git@google.com/) - "crypto: mips/crc32 - fix the CRC32C implementation" (https://lore.kernel.org/linux-crypto/20241020180258.8060-1-ebiggers@kernel.org/) Everything can be retrieved from git using the command given earlier. Since this patchset touches many areas, getting it merged may be difficult. One option is a pull request with the whole patchset directly to Linus. Another is to have at least patches 1-2 and the above dependencies taken through the crypto tree in v6.13; then the arch patches can land separately afterwards, followed by the rest. Eric Biggers (15): lib/crc32: drop leading underscores from __crc32c_le_base lib/crc32: improve support for arch-specific overrides arm/crc32: expose CRC32 functions through lib loongarch/crc32: expose CRC32 functions through lib mips/crc32: expose CRC32 functions through lib powerpc/crc32: expose CRC32 functions through lib s390/crc32: expose CRC32 functions through lib sparc/crc32: expose CRC32 functions through lib x86/crc32: update prototype for crc_pcl() x86/crc32: update prototype for crc32_pclmul_le_16() x86/crc32: expose CRC32 functions through lib lib/crc32: make crc32c() go directly to lib ext4: switch to using the crc32c library jbd2: switch to using the crc32c library f2fs: switch to using the crc32 library arch/arm/Kconfig | 1 + arch/arm/configs/milbeaut_m10v_defconfig | 1 - arch/arm/configs/multi_v7_defconfig | 1 - arch/arm/crypto/Kconfig | 14 - arch/arm/crypto/Makefile | 2 - arch/arm/crypto/crc32-ce-glue.c | 247 ------------ arch/arm/lib/Makefile | 3 + .../crc32-ce-core.S => lib/crc32-core.S} | 0 arch/arm/lib/crc32-glue.c | 115 ++++++ arch/arm64/Kconfig | 1 + arch/arm64/lib/Makefile | 3 +- arch/arm64/lib/crc32-glue.c | 15 +- arch/loongarch/Kconfig | 1 + arch/loongarch/configs/loongson3_defconfig | 1 - arch/loongarch/crypto/Kconfig | 9 - arch/loongarch/crypto/Makefile | 2 - arch/loongarch/crypto/crc32-loongarch.c | 300 --------------- arch/loongarch/lib/Makefile | 2 + arch/loongarch/lib/crc32-loongarch.c | 127 +++++++ arch/mips/Kconfig | 5 +- arch/mips/configs/eyeq5_defconfig | 1 - arch/mips/configs/eyeq6_defconfig | 1 - arch/mips/configs/generic/32r6.config | 2 - arch/mips/configs/generic/64r6.config | 1 - arch/mips/crypto/Kconfig | 9 - arch/mips/crypto/Makefile | 2 - arch/mips/crypto/crc32-mips.c | 354 ------------------ arch/mips/lib/Makefile | 2 + arch/mips/lib/crc32-mips.c | 184 +++++++++ arch/powerpc/Kconfig | 1 + arch/powerpc/configs/powernv_defconfig | 1 - arch/powerpc/configs/ppc64_defconfig | 1 - arch/powerpc/crypto/Kconfig | 15 +- arch/powerpc/crypto/Makefile | 2 - arch/powerpc/crypto/crc32c-vpmsum_glue.c | 173 --------- arch/powerpc/crypto/crct10dif-vpmsum_asm.S | 2 +- arch/powerpc/lib/Makefile | 3 + arch/powerpc/lib/crc32-glue.c | 84 +++++ .../{crypto => lib}/crc32-vpmsum_core.S | 0 .../{crypto => lib}/crc32c-vpmsum_asm.S | 0 arch/riscv/Kconfig | 1 + arch/riscv/lib/Makefile | 3 +- arch/riscv/lib/{crc32.c => crc32-riscv.c} | 15 +- arch/s390/Kconfig | 1 + arch/s390/configs/debug_defconfig | 1 - arch/s390/configs/defconfig | 1 - arch/s390/crypto/Kconfig | 12 - arch/s390/crypto/Makefile | 2 - arch/s390/crypto/crc32-vx.c | 306 --------------- arch/s390/lib/Makefile | 3 + arch/s390/lib/crc32-glue.c | 82 ++++ arch/s390/{crypto => lib}/crc32-vx.h | 0 arch/s390/{crypto => lib}/crc32be-vx.c | 0 arch/s390/{crypto => lib}/crc32le-vx.c | 0 arch/sparc/Kconfig | 1 + arch/sparc/crypto/Kconfig | 10 - arch/sparc/crypto/Makefile | 4 - arch/sparc/crypto/crc32c_glue.c | 184 --------- arch/sparc/lib/Makefile | 2 + arch/sparc/lib/crc32_glue.c | 85 +++++ arch/sparc/{crypto => lib}/crc32c_asm.S | 2 +- arch/x86/Kconfig | 1 + arch/x86/crypto/Kconfig | 22 -- arch/x86/crypto/Makefile | 7 - arch/x86/crypto/crc32-pclmul_glue.c | 202 ---------- arch/x86/crypto/crc32c-intel_glue.c | 250 ------------- arch/x86/lib/Makefile | 4 + arch/x86/lib/crc32-glue.c | 112 ++++++ .../crc32-pclmul_asm.S => lib/crc32-pclmul.S} | 19 +- .../crc32c-3way.S} | 63 ++-- crypto/crc32_generic.c | 4 +- crypto/crc32c_generic.c | 8 +- drivers/target/iscsi/Kconfig | 1 - fs/ext4/Kconfig | 3 +- fs/ext4/ext4.h | 25 +- fs/ext4/super.c | 15 - fs/f2fs/Kconfig | 3 +- fs/f2fs/f2fs.h | 19 +- fs/f2fs/super.c | 15 - fs/jbd2/Kconfig | 2 - fs/jbd2/journal.c | 25 +- include/linux/crc32.h | 35 +- include/linux/crc32c.h | 7 +- include/linux/jbd2.h | 31 +- lib/Kconfig | 80 ++-- lib/Makefile | 1 - lib/crc32.c | 24 +- lib/crc32test.c | 2 +- lib/libcrc32c.c | 74 ---- 89 files changed, 1002 insertions(+), 2455 deletions(-) delete mode 100644 arch/arm/crypto/crc32-ce-glue.c rename arch/arm/{crypto/crc32-ce-core.S => lib/crc32-core.S} (100%) create mode 100644 arch/arm/lib/crc32-glue.c delete mode 100644 arch/loongarch/crypto/crc32-loongarch.c create mode 100644 arch/loongarch/lib/crc32-loongarch.c delete mode 100644 arch/mips/crypto/crc32-mips.c create mode 100644 arch/mips/lib/crc32-mips.c delete mode 100644 arch/powerpc/crypto/crc32c-vpmsum_glue.c create mode 100644 arch/powerpc/lib/crc32-glue.c rename arch/powerpc/{crypto => lib}/crc32-vpmsum_core.S (100%) rename arch/powerpc/{crypto => lib}/crc32c-vpmsum_asm.S (100%) rename arch/riscv/lib/{crc32.c => crc32-riscv.c} (94%) delete mode 100644 arch/s390/crypto/crc32-vx.c create mode 100644 arch/s390/lib/crc32-glue.c rename arch/s390/{crypto => lib}/crc32-vx.h (100%) rename arch/s390/{crypto => lib}/crc32be-vx.c (100%) rename arch/s390/{crypto => lib}/crc32le-vx.c (100%) delete mode 100644 arch/sparc/crypto/crc32c_glue.c create mode 100644 arch/sparc/lib/crc32_glue.c rename arch/sparc/{crypto => lib}/crc32c_asm.S (92%) delete mode 100644 arch/x86/crypto/crc32-pclmul_glue.c delete mode 100644 arch/x86/crypto/crc32c-intel_glue.c create mode 100644 arch/x86/lib/crc32-glue.c rename arch/x86/{crypto/crc32-pclmul_asm.S => lib/crc32-pclmul.S} (95%) rename arch/x86/{crypto/crc32c-pcl-intel-asm_64.S => lib/crc32c-3way.S} (92%) delete mode 100644 lib/libcrc32c.c