Re: [PATCH v2 1/2] MIPS: SGI-IP27: micro-optimize arch_init_irq()

[Thomas Bogendoerfer <tsbogend@alpha.franken.de>]

On Mon, Apr 22, 2024 at 04:04:23PM -0700, Yury Norov wrote:
> On Wed, Apr 17, 2024 at 01:10:52PM +0200, Thomas Bogendoerfer wrote:
> > On Tue, Apr 16, 2024 at 10:37:10AM -0700, Yury Norov wrote:
> > > The function sets adjusted groups of bits in hub_irq_map by using
> > > for-loops. There's a bitmap_set() function dedicated to do this.
> > > 
> > > Because [0, CPU_CALL_B_IRQ] and [NI_BRDCAST_ERR_A, MSC_PANIC_INTR]
> > > ranges belong to the same machine word, bitmap_set() would boil down
> > > to an inline wrapper in both cases, avoiding generating a loop, with
> > > the associate overhead. Effectively, it would be a compile-time:
> > > 
> > > 	*hub_irq_map = GENMASK() | GENMASK();
> > > 
> > > Signed-off-by: Yury Norov <yury.norov@gmail.com>
> > > ---
> > >  arch/mips/sgi-ip27/ip27-irq.c | 8 ++------
> > >  1 file changed, 2 insertions(+), 6 deletions(-)
> > > 
> > > diff --git a/arch/mips/sgi-ip27/ip27-irq.c b/arch/mips/sgi-ip27/ip27-irq.c
> > > index 8f5299b269e7..d8acdf0439d2 100644
> > > --- a/arch/mips/sgi-ip27/ip27-irq.c
> > > +++ b/arch/mips/sgi-ip27/ip27-irq.c
> > > @@ -277,7 +277,6 @@ void __init arch_init_irq(void)
> > >  {
> > >  	struct irq_domain *domain;
> > >  	struct fwnode_handle *fn;
> > > -	int i;
> > 
> > I've already applied your first version, so I need an incremental
> > patch, which just removes the unused variable.
> 
> Sure, please find below.
> 
> >From ce447fe69092c48bb59a6c4cb08ee5f9080f0ad6 Mon Sep 17 00:00:00 2001
> From: Yury Norov <yury.norov@gmail.com>
> Date: Mon, 22 Apr 2024 15:52:12 -0700
> Subject: [PATCH] MIPS: SGI-IP27: fix -Wunused-variable in arch_init_irq()
> 
> Commit 40e20fbccfb722f21 (MIPS: SGI-IP27: micro-optimize arch_init_irq())
> replaced a for-loop iteration with bitmap_set() calls, but didn't remove
> an iteration variable.
> 
> Fixes: 40e20fbccfb722f21 (MIPS: SGI-IP27: micro-optimize arch_init_irq())
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202404161933.izfqZ32k-lkp@intel.com/
> Signed-off-by: Yury Norov <yury.norov@gmail.com>
> ---
>  arch/mips/sgi-ip27/ip27-irq.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/arch/mips/sgi-ip27/ip27-irq.c b/arch/mips/sgi-ip27/ip27-irq.c
> index dcb14a234b1c..d8acdf0439d2 100644
> --- a/arch/mips/sgi-ip27/ip27-irq.c
> +++ b/arch/mips/sgi-ip27/ip27-irq.c
> @@ -277,7 +277,6 @@ void __init arch_init_irq(void)
>  {
>  	struct irq_domain *domain;
>  	struct fwnode_handle *fn;
> -	int i;
>  
>  	mips_cpu_irq_init();
>  
> -- 
> 2.40.1

applied to mips-next.

Thomas.

-- 
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