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* [PATCH v3 0/5] sparc64: Optimize fls and __fls
@ 2017-10-06 16:54 Vijay Kumar
  2017-10-06 16:54 ` [PATCH v3 1/5] sparc64: Define SPARC default fls function Vijay Kumar
                   ` (4 more replies)
  0 siblings, 5 replies; 9+ messages in thread
From: Vijay Kumar @ 2017-10-06 16:54 UTC (permalink / raw)
  To: davem; +Cc: linux-kernel, sparclinux, babu.moger, rob.gardner, sam

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.

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 (2):
  sparc64: Define SPARC default fls and __fls
  sparc64: Use lzcnt instruction for fls and __fls

 arch/sparc/Makefile                |    1 +
 arch/sparc/include/asm/bitops_64.h |    7 +-
 arch/sparc/kernel/head_64.S        |    2 +
 arch/sparc/lib/Makefile            |    4 +
 arch/sparc/lib/NG4fls.S            |   31 +++++++++
 arch/sparc/lib/NG4patch.S          |    9 +++
 arch/sparc/lib/fls.S               |  126 ++++++++++++++++++++++++++++++++++++
 7 files changed, 177 insertions(+), 3 deletions(-)
 create mode 100644 arch/sparc/lib/NG4fls.S
 create mode 100644 arch/sparc/lib/fls.S

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2017-10-09 15:11 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-10-06 16:54 [PATCH v3 0/5] sparc64: Optimize fls and __fls Vijay Kumar
2017-10-06 16:54 ` [PATCH v3 1/5] sparc64: Define SPARC default fls function Vijay Kumar
2017-10-06 16:54 ` [PATCH v3 2/5] sparc64: Define SPARC default __fls function Vijay Kumar
2017-10-06 16:54 ` [PATCH v3 3/5] sparc64: SPARC optimised fls function Vijay Kumar
2017-10-06 23:28   ` Anthony Yznaga
2017-10-09  4:39   ` David Miller
2017-10-09 15:12     ` Vijay Kumar
2017-10-06 16:54 ` [PATCH v3 4/5] sparc64: SPARC optimised __fls function Vijay Kumar
2017-10-06 16:54 ` [PATCH v3 5/5] sparc64: Use sparc optimised fls and __fls for T4 and above Vijay Kumar

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