kernel/linux.git/arch/s390/lib, branch v7.2-rc2

s390/tishift: Convert ashlti3(), ashrti3(), __lshrti3() to C

2026-06-10T14:55:22+00:00

There is no reason to have __ashlti3(), __ashrti3(), and __lshrti3() implemented in assembler. Convert them all to C, which allows the compiler to optimize the code if newer instructions allow that. Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/memmove: Optimize backward copy case

2026-06-10T14:55:21+00:00

memmove() copies byte wise for the backward copy case, when the mvc instruction cannot be used. This is quite slow, but can be optimized with the mvcrl instruction, which is available since z15. Some numbers (measured on a shared z16 LPAR) show that the new implementation is nearly always faster, except for the non realistic one and two byte cases: size old new 1 2ns 3ns 2 4ns 5ns 4 5ns 5ns 8 8ns 5ns 16 12ns 6ns 32 8ns 7ns 64 15ns 7ns 128 31ns 9ns 256 64ns 10ns 512 129ns 18ns 1024 250ns 19ns 2048 498ns 38ns Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/string: Convert memset(16|32|64)() to C

2026-06-10T14:55:21+00:00

Convert memset(16|32|64)() from assembler to C, which should make it easier to read and change, if required. And it allows the compiler to optimize the code, and use different instructions, except for the used inline assemblies. Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/string: Convert memcpy() to C

2026-06-10T14:55:21+00:00

Convert memcpy() from assembler to C, which should make it easier to read and change, if required. And it allows the compiler to optimize the code, and use different instructions, except for the used inline assemblies. Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/string: Convert memset() to C

2026-06-10T14:55:21+00:00

Convert memset() from assembler to C, which should make it easier to read and change, if required. And it allows the compiler to optimize the code, and use different instructions, except for the used inline assemblies. Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/string: Convert memmove() to C

2026-06-10T14:55:20+00:00

Convert memmove() from assembler to C, which should make it easier to read and change, if required. And it allows the compiler to optimize the code, and use different instructions, except for the used inline assemblies. Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/string: Add -ffreestanding compile option to string.o

2026-06-10T14:55:20+00:00

Use -ffreestanding for string.o to avoid that the compiler generates calls into themselves for standard library functions like memset(). Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/string: Remove strlcat() implementation

2026-05-30T09:37:25+00:00

strlcat() shouldn't be used anymore (see fortify-string.h), and will be deprecated / removed sooner or later [1]. Therefore remove the s390 implementation of strlcat() in favor of the generic variant. [1] https://lore.kernel.org/all/20260514160719.105084-3-manuelebner@mailbox.org/ Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390: move the XOR code to lib/raid/

2026-04-03T06:36:19+00:00

Move the optimized XOR into lib/raid and include it it in xor.ko instead of unconditionally building it into the main kernel image. Link: https://lkml.kernel.org/r/20260327061704.3707577-19-hch@lst.de Signed-off-by: Christoph Hellwig Acked-by: Heiko Carstens Reviewed-by: Eric Biggers Tested-by: Eric Biggers Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Andreas Larsson Cc: Anton Ivanov Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David S. Miller Cc: David Sterba Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Jason A. Donenfeld Cc: Johannes Berg Cc: Li Nan Cc: Madhavan Srinivasan Cc: Magnus Lindholm Cc: Matt Turner Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Richard Henderson Cc: Richard Weinberger Cc: Russell King Cc: Song Liu Cc: Sven Schnelle Cc: Ted Ts'o Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton

xor: split xor.h

2026-04-03T06:36:17+00:00

Keep xor.h for the public API, and split the struct xor_block_template definition that is only needed by the xor.ko core and architecture-specific optimizations into a separate xor_impl.h header. Link: https://lkml.kernel.org/r/20260327061704.3707577-9-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Eric Biggers Tested-by: Eric Biggers Cc: Albert Ou Cc: Alexander Gordeev Cc: Alexandre Ghiti Cc: Andreas Larsson Cc: Anton Ivanov Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: "Borislav Petkov (AMD)" Cc: Catalin Marinas Cc: Chris Mason Cc: Christian Borntraeger Cc: Dan Williams Cc: David S. Miller Cc: David Sterba Cc: Heiko Carstens Cc: Herbert Xu Cc: "H. Peter Anvin" Cc: Huacai Chen Cc: Ingo Molnar Cc: Jason A. Donenfeld Cc: Johannes Berg Cc: Li Nan Cc: Madhavan Srinivasan Cc: Magnus Lindholm Cc: Matt Turner Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Richard Henderson Cc: Richard Weinberger Cc: Russell King Cc: Song Liu Cc: Sven Schnelle Cc: Ted Ts'o Cc: Vasily Gorbik Cc: WANG Xuerui Cc: Will Deacon Signed-off-by: Andrew Morton

kernel/linux.git/arch/s390/lib, branch v7.2-rc2

s390/tishift: Convert __ashlti3(), __ashrti3(), __lshrti3() to C

s390/memmove: Optimize backward copy case

s390/string: Convert memset(16|32|64)() to C

s390/string: Convert memcpy() to C

s390/string: Convert memset() to C

s390/string: Convert memmove() to C

s390/string: Add -ffreestanding compile option to string.o

s390/string: Remove strlcat() implementation

s390: move the XOR code to lib/raid/

xor: split xor.h

s390/tishift: Convert ashlti3(), ashrti3(), __lshrti3() to C