Re: [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT

2021-03-05 Thread Catalin Marinas
On Wed, Mar 03, 2021 at 02:17:41PM -0800, Yury Norov wrote: > On Thu, Feb 25, 2021 at 02:02:06PM +, Will Deacon wrote: > > On Thu, Feb 25, 2021 at 05:56:59AM -0800, Yury Norov wrote: > > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > > > index 31bd885b79eb..5596eab04092 100644 > > >

Re: [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT

2021-03-03 Thread Yury Norov
On Thu, Feb 25, 2021 at 02:02:06PM +, Will Deacon wrote: > On Thu, Feb 25, 2021 at 05:56:59AM -0800, Yury Norov wrote: > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > > index 31bd885b79eb..5596eab04092 100644 > > --- a/arch/arm64/Kconfig > > +++ b/arch/arm64/Kconfig > > @@ -108,6

Re: [RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT

2021-02-25 Thread Will Deacon
On Thu, Feb 25, 2021 at 05:56:59AM -0800, Yury Norov wrote: > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 31bd885b79eb..5596eab04092 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -108,6 +108,7 @@ config ARM64 > select GENERIC_CPU_AUTOPROBE > select

[RESEND PATCH 1/2] ARM64: enable GENERIC_FIND_FIRST_BIT

2021-02-25 Thread Yury Norov
ARM64 doesn't implement find_first_{zero}_bit in arch code and doesn't enable it in a config. It leads to using find_next_bit() which is less efficient: : 0: aa0003e4mov x4, x0 4: aa0103e0mov x0, x1 8: b4000181cbz x1, 38 c: