user/sven/linux.git/lib/crc32.c, branch v5.4.69

lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases as __pure

2019-02-15T18:50:07Z

The upcoming GCC 9 release extends the -Wmissing-attributes warnings (enabled by -Wall) to C and aliases: it warns when particular function attributes are missing in the aliases but not in their target. In particular, it triggers here because crc32_le_base/__crc32c_le_base aren't __pure while their target crc32_le/__crc32c_le are. These aliases are used by architectures as a fallback in accelerated versions of CRC32. See commit 9784d82db3eb ("lib/crc32: make core crc32() routines weak so they can be overridden"). Therefore, being fallbacks, it is likely that even if the aliases were called from C, there wouldn't be any optimizations possible. Currently, the only user is arm64, which calls this from asm. Still, marking the aliases as __pure makes sense and is a good idea for documentation purposes and possible future optimizations, which also silences the warning. Acked-by: Ard Biesheuvel Tested-by: Laura Abbott Signed-off-by: Miguel Ojeda

lib/crc32: make core crc32() routines weak so they can be overridden

2018-09-10T15:09:27Z

Allow architectures to drop in accelerated CRC32 routines by making the crc32_le/__crc32c_le entry points weak, and exposing non-weak aliases for them that may be used by the accelerated versions as fallbacks in case the instructions they rely upon are not available. Acked-by: Herbert Xu Signed-off-by: Ard Biesheuvel Signed-off-by: Catalin Marinas

lib/crc: Use consistent naming for CRC-32 polynomials

2018-07-27T11:04:33Z

Header was defining CRCPOLY_LE/BE and CRC32C_POLY_LE but in fact all of them are CRC-32 polynomials so use consistent naming. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Herbert Xu

lib/crc: Move polynomial definition to separate header

2018-07-27T11:04:33Z

Allow other drivers and parts of kernel to use the same define for CRC32 polynomial, instead of duplicating it in many places. This code does not bring any functional changes, except moving existing code. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Herbert Xu

docs: clean up and add rest of CRC functions to kernel-api.rst

2017-09-26T21:01:20Z

Add the rest of the CRC library functions to kernel-api. - try to clarify crc32() by adding '@' to a function parameter - reorder kernel-api CRC functions to be less random - add more CRC functions to kernel-api - correct the function parameter names in several places Signed-off-by: Randy Dunlap Signed-off-by: Jonathan Corbet

lib: add module support to crc32 tests

2017-02-25T01:46:57Z

Extract the crc32 test code into its own source file, to allow to compile it either to a loadable module, or builtin into the kernel. Link: http://lkml.kernel.org/r/1483470276-10517-1-git-send-email-geert@linux-m68k.org Signed-off-by: Geert Uytterhoeven Reviewed-by: Andy Shevchenko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

crc32: use ktime_get_ns() for measurement

2016-08-02T23:35:08Z

The crc32 test function measures the elapsed time in nanoseconds, but uses 'struct timespec' for that. We want to remove timespec from the kernel for y2038 compatibility, and ktime_get_ns() also helps make the code simpler here. It is also slightly better to use monontonic time, as we are only interested in the time difference. Link: http://lkml.kernel.org/r/20160617143932.3289626-1-arnd@arndb.de Signed-off-by: Arnd Bergmann Cc: "David S . Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib: crc32: Add some additional __pure annotations

2014-06-25T23:04:00Z

In case they help the compiler. Signed-off-by: George Spelvin Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

lib: crc32: Mark test data __initconst

2014-06-25T23:03:59Z

So it gets discarded after the selftest. Signed-off-by: George Spelvin Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

lib: crc32: Greatly shrink CRC combining code

2014-06-25T23:03:59Z

There's no need for a full 32x32 matrix, when rows before the last are just shifted copies of the rows after them. There's still room for improvement (especially on X86 processors with CRC32 and PCLMUL instructions), but this is a large step in the right direction [which is in particular useful for its current user, namely SCTP checksumming over multiple skb frags[] entries, i.e. in IPVS balancing when other CRC32 offloads are not available]. The internal primitive is now called crc32_generic_shift and takes one less argument; the XOR with crc2 is done in inline wrappers. Signed-off-by: George Spelvin Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller