pm24.git/include/linux/math64.h, branch rust-fixes-6.10

vdso, math64: Provide mul_u64_u32_add_u64_shr()

2024-04-08T13:03:07Z

Provide mul_u64_u32_add_u64_shr() which is a calculation that will be used by timekeeping and VDSO. Place #include after #include to allow architecture-specific overrides, at least for the kernel. Signed-off-by: Adrian Hunter Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20240325064023.2997-6-adrian.hunter@intel.com

math64: Tidy up mul_u64_u32_shr()

2024-04-08T13:03:06Z

Put together declaration and initialization of local variables. Suggested-by: Thomas Gleixner Signed-off-by: Adrian Hunter Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20240325064023.2997-5-adrian.hunter@intel.com

math64: Always inline u128 version of mul_u64_u64_shr()

2023-06-05T19:11:06Z

In order to prevent the following complaint from happening, always inline the u128 variant of mul_u64_u64_shr() -- which is what x86_64 will use. vmlinux.o: warning: objtool: read_hv_sched_clock_tsc+0x5a: call to mul_u64_u64_shr.constprop.0() leaves .noinstr.text section It should compile into something like: asm("mul %[mul];" "shrd %rdx, %rax, %cl" : "+&a" (a) : "c" shift, [mul] "r" (mul) : "d"); Which is silly not to inline, but it happens. Signed-off-by: Peter Zijlstra (Intel) Tested-by: Michael Kelley # Hyper-V Link: https://lore.kernel.org/r/20230519102715.637420396@infradead.org

sched/clock/x86: Mark sched_clock() noinstr

2023-01-31T14:01:47Z

In order to use sched_clock() from noinstr code, mark it and all it's implenentations noinstr. The whole pvclock thing (used by KVM/Xen) is a bit of a pain, since it calls out to watchdogs, create a pvclock_clocksource_read_nowd() variant doesn't do that and can be noinstr. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20230126151323.702003578@infradead.org

math64: fix kernel-doc return value warnings

2022-11-21T21:30:54Z

Fix the following kernel-doc warnings by adding a description for return values of div_[us]64. math64.h:126: warning: No description found for return value of 'div_u64' math64.h:139: warning: No description found for return value of 'div_s64' Signed-off-by: Liam Beguin Link: https://lore.kernel.org/r/20221118182309.3824530-3-liambeguin@gmail.com Signed-off-by: Jonathan Corbet

math64: add kernel-doc for DIV64_U64_ROUND_UP

2022-11-21T21:30:54Z

Add kernel-doc for DIV64_U64_ROUND_UP so that it appears in the documentation. Signed-off-by: Liam Beguin Acked-by: Randy Dunlap Tested-by: Randy Dunlap Link: https://lore.kernel.org/r/20221118182309.3824530-2-liambeguin@gmail.com Signed-off-by: Jonathan Corbet

math64: favor kernel-doc from header files

2022-11-21T21:30:53Z

Fix the kernel-doc markings for div64 functions to point to the header file instead of the lib/ directory. This avoids having implementation specific comments in generic documentation. Furthermore, given that some kernel-doc comments are identical, drop them from lib/math64 and only keep there comments that add implementation details. Signed-off-by: Liam Beguin Acked-by: Randy Dunlap Tested-by: Randy Dunlap Link: https://lore.kernel.org/r/20221118182309.3824530-1-liambeguin@gmail.com Signed-off-by: Jonathan Corbet

math64: New DIV_U64_ROUND_CLOSEST helper

2022-02-25T09:27:57Z

Provide DIV_U64_ROUND_CLOSEST helper which uses div_u64 to perform division rounded to the closest integer using unsigned 64bit dividend and unsigned 32bit divisor. Reviewed-by: Marek Behún Signed-off-by: Pali Rohár Signed-off-by: Marek Behún Link: https://lore.kernel.org/r/20220219152818.4319-2-kabel@kernel.org Signed-off-by: Greg Kroah-Hartman

math64.h: Add mul_s64_u64_shr()

2021-06-17T17:09:27Z

This function is needed for KVM's nested virtualization. The nested TSC scaling implementation requires multiplying the signed TSC offset with the unsigned TSC multiplier. Signed-off-by: Ilias Stamatis Reviewed-by: Maxim Levitsky Message-Id: <20210526184418.28881-2-ilstam@amazon.com> Signed-off-by: Paolo Bonzini

math64.h: kernel-docs: Convert some markups into normal comments

2020-10-15T05:49:46Z

There are several functions at math64.h that are also defined at div64.c. As both are included at kernel-api.rst, Sphinx 3.x complains about symbol duplication: ./lib/math/div64.c:73: WARNING: Duplicate C declaration, also defined in 'core-api/kernel-api'. Declaration is 'div_s64_rem'. ./lib/math/div64.c:104: WARNING: Duplicate C declaration, also defined in 'core-api/kernel-api'. Declaration is 'div64_u64_rem'. ./lib/math/div64.c:144: WARNING: Duplicate C declaration, also defined in 'core-api/kernel-api'. Declaration is 'div64_u64'. ./lib/math/div64.c:172: WARNING: Duplicate C declaration, also defined in 'core-api/kernel-api'. Declaration is 'div64_s64'. In order to avoid Sphinx warnings about duplication, change the kernel-doc markups to just comments at math64.h. Reviewed-by: Vincenzo Frascino Signed-off-by: Mauro Carvalho Chehab