All of lore.kernel.org
 help / color / mirror / Atom feed
From: Guo Ren <ren_guo@c-sky.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: akpm@linux-foundation.org, arnd@arndb.de,
	daniel.lezcano@linaro.org, davem@davemloft.net,
	gregkh@linuxfoundation.org, jason@lakedaemon.net,
	marc.zyngier@arm.com, mark.rutland@arm.com,
	mchehab+samsung@kernel.org, peterz@infradead.org,
	robh@kernel.org, robh+dt@kernel.org, tglx@linutronix.de,
	linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
	devicetree@vger.kernel.org, green.hu@gmail.com,
	Chen Linfei <linfei_chen@c-sky.com>, Mao Han <han_mao@c-sky.com>
Subject: Re: [PATCH V6 13/33] csky: Library functions
Date: Sun, 30 Sep 2018 01:00:11 +0800	[thread overview]
Message-ID: <20180929170011.GA27796@guoren-Inspiron-7460> (raw)
In-Reply-To: <20180928162030.GE19827@infradead.org>

On Fri, Sep 28, 2018 at 09:20:30AM -0700, Christoph Hellwig wrote:
> > +unsigned long long notrace __bswapdi2(unsigned long long u)
> > +{
> > +	return (((u) & 0xff00000000000000ull) >> 56) |
> > +	       (((u) & 0x00ff000000000000ull) >> 40) |
> > +	       (((u) & 0x0000ff0000000000ull) >> 24) |
> > +	       (((u) & 0x000000ff00000000ull) >>  8) |
> > +	       (((u) & 0x00000000ff000000ull) <<  8) |
> > +	       (((u) & 0x0000000000ff0000ull) << 24) |
> > +	       (((u) & 0x000000000000ff00ull) << 40) |
> > +	       (((u) & 0x00000000000000ffull) << 56);
> > +}
> 
> How is this any better than using the generic byteswap helpers?
OK.
#include <uapi/linux/swab.h>

unsigned long long notrace __bswapdi2(unsigned long long u)
{
	return ___constant_swab64(u);


> 
> > +unsigned int notrace __bswapsi2(unsigned int u)
> > +{
> > +	return (((u) & 0xff000000) >> 24) |
> > +	       (((u) & 0x00ff0000) >>  8) |
> > +	       (((u) & 0x0000ff00) <<  8) |
> > +	       (((u) & 0x000000ff) << 24);
> > +}
> 
> Same here.
OK.
#include <uapi/linux/swab.h>

unsigned int notrace __bswapsi2(unsigned int u)
{
	return ___constant_swab32(u);
}

Thx
 Guo Ren

  reply	other threads:[~2018-09-29 17:00 UTC|newest]

Thread overview: 56+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-27 14:47 [PATCH V6 00/33] C-SKY(csky) Linux Kernel Port Guo Ren
2018-09-27 14:47 ` [PATCH V6 01/33] csky: Build infrastructure Guo Ren
2018-09-28 16:11   ` Christoph Hellwig
2018-09-29 17:20     ` Guo Ren
2018-09-27 14:47 ` [PATCH V6 02/33] csky: defconfig Guo Ren
2018-09-27 14:47 ` [PATCH V6 03/33] csky: Kernel booting Guo Ren
2018-09-28 16:13   ` Christoph Hellwig
2018-09-29 17:09     ` Guo Ren
2018-09-27 14:47 ` [PATCH V6 04/33] csky: Exception handling and mm-fault Guo Ren
2018-09-28 16:15   ` Christoph Hellwig
2018-09-29 17:07     ` Guo Ren
2018-09-27 14:47 ` [PATCH V6 05/33] csky: System Call Guo Ren
2018-09-28 16:16   ` Christoph Hellwig
2018-09-29 17:05     ` Guo Ren
2018-09-27 14:47 ` [PATCH V6 06/33] csky: Cache and TLB routines Guo Ren
2018-09-27 14:47 ` [PATCH V6 07/33] csky: MMU and page table management Guo Ren
2018-09-27 15:47   ` Christoph Hellwig
2018-09-28 13:08     ` Guo Ren
2018-09-29 17:04     ` Guo Ren
2018-09-27 14:47 ` [PATCH V6 08/33] csky: Process management and Signal Guo Ren
2018-09-27 19:50   ` Eric W. Biederman
2018-09-28 13:10     ` Guo Ren
2018-09-29 17:01     ` Guo Ren
2018-09-27 14:47 ` [PATCH V6 09/33] csky: VDSO and rt_sigreturn Guo Ren
2018-09-27 14:47 ` [PATCH V6 10/33] csky: IRQ handling Guo Ren
2018-09-27 15:49   ` Christoph Hellwig
2018-09-28 13:09     ` Guo Ren
2018-09-29 17:00     ` Guo Ren
2018-09-27 14:47 ` [PATCH V6 11/33] csky: Atomic operations Guo Ren
2018-09-27 14:47 ` [PATCH V6 12/33] csky: ELF and module probe Guo Ren
2018-09-27 14:47 ` [PATCH V6 13/33] csky: Library functions Guo Ren
2018-09-28 16:20   ` Christoph Hellwig
2018-09-29 17:00     ` Guo Ren [this message]
2018-09-27 14:47 ` [PATCH V6 14/33] csky: User access Guo Ren
2018-09-27 14:47 ` [PATCH V6 15/33] csky: Debug and Ptrace GDB Guo Ren
2018-09-27 14:47 ` [PATCH V6 16/33] csky: SMP support Guo Ren
2018-09-27 14:47 ` [PATCH V6 17/33] csky: Misc headers Guo Ren
2018-09-28  0:51 ` [PATCH V6 18/33] dt-bindings: csky CPU Bindings Guo Ren
2018-09-28  0:51 ` [PATCH V6 19/33] dt-bindings: Add vendor prefix for csky Guo Ren
2018-09-28  0:51 ` [PATCH V6 20/33] csky/dma: fix up dma_mapping error Guo Ren
2018-09-28 16:21   ` Christoph Hellwig
2018-09-29 15:08     ` Guo Ren
2018-09-30 11:10       ` Guo Ren
2018-09-28  0:51 ` [PATCH V6 21/33] csky: remove irq_mapping from smp.c Guo Ren
2018-09-28  0:51 ` [PATCH V6 22/33] irqchip: add C-SKY SMP interrupt controller Guo Ren
2018-09-28  0:51 ` [PATCH V6 23/33] dt-bindings: interrupt-controller: C-SKY SMP intc Guo Ren
2018-09-28  0:51 ` [PATCH V6 24/33] clocksource: add C-SKY SMP timer Guo Ren
2018-09-28  0:51 ` [PATCH V6 25/33] dt-bindings: timer: C-SKY Multi-processor timer Guo Ren
2018-09-28  0:51 ` [PATCH V6 26/33] MAINTAINERS: Add csky Guo Ren
2018-09-28  0:51 ` [PATCH V6 27/33] dt-bindings: interrupt-controller: C-SKY APB intc Guo Ren
2018-09-28  0:51 ` [PATCH V6 28/33] irqchip: add C-SKY APB bus interrupt controller Guo Ren
2018-09-28  0:51 ` [PATCH V6 29/33] dt-bindings: timer: gx6605s SOC timer Guo Ren
2018-09-28  0:51 ` [PATCH V6 30/33] clocksource: add gx6605s SOC system timer Guo Ren
2018-09-28  0:51 ` [PATCH V6 31/33] csky: fix compile error in linux/bug.h with SMP enabled Guo Ren
2018-09-28  0:51 ` [PATCH V6 32/33] csky: fix flush_cache_range and tlb_start_vma Guo Ren
2018-09-28  0:51 ` [PATCH V6 33/33] csky: use asm-generic/bitops/atomic.h for all Guo Ren

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180929170011.GA27796@guoren-Inspiron-7460 \
    --to=ren_guo@c-sky.com \
    --cc=akpm@linux-foundation.org \
    --cc=arnd@arndb.de \
    --cc=daniel.lezcano@linaro.org \
    --cc=davem@davemloft.net \
    --cc=devicetree@vger.kernel.org \
    --cc=green.hu@gmail.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=han_mao@c-sky.com \
    --cc=hch@infradead.org \
    --cc=jason@lakedaemon.net \
    --cc=linfei_chen@c-sky.com \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marc.zyngier@arm.com \
    --cc=mark.rutland@arm.com \
    --cc=mchehab+samsung@kernel.org \
    --cc=peterz@infradead.org \
    --cc=robh+dt@kernel.org \
    --cc=robh@kernel.org \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.