Messages in this thread | | | From | Vijay Kumar <> | Subject | [PATCH v4 0/5] sparc64: Optimize fls and __fls | Date | Wed, 11 Oct 2017 12:50:01 -0600 |
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SPARC provides lzcnt instruction (with VIS3) which can be used to optimize fls, __fls and fls64 functions. For the systems that supports lzcnt instruction, we now do boot time patching to use sparc optimized fls, __fls and fls64 functions.
v3->v4: - Fixed a typo. v2->v3: - Using ENTRY(), ENDPROC() for assembler functions. - Removed BITS_PER_LONG from __fls. - Using generic fls64(). - Replaced lzcnt instruction with .word directive. v1->v2: - Fixed delay slot issue.
Vijay Kumar (5): sparc64: Define SPARC default fls function sparc64: Define SPARC default __fls function sparc64: SPARC optimized fls function sparc64: SPARC optimized __fls function sparc64: Use sparc optimized fls and __fls for T4 and above
arch/sparc/include/asm/bitops_64.h | 5 ++- arch/sparc/kernel/head_64.S | 2 + arch/sparc/lib/Makefile | 3 ++ arch/sparc/lib/NG4fls.S | 30 ++++++++++++++++ arch/sparc/lib/NG4patch.S | 9 +++++ arch/sparc/lib/fls.S | 67 ++++++++++++++++++++++++++++++++++++ arch/sparc/lib/fls64.S | 61 ++++++++++++++++++++++++++++++++ 7 files changed, 175 insertions(+), 2 deletions(-) create mode 100644 arch/sparc/lib/NG4fls.S create mode 100644 arch/sparc/lib/fls.S create mode 100644 arch/sparc/lib/fls64.S
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