Re: [PATCH 2/5] nvmem: mtk-efuse: use stack for nvmem_config instead of malloc'ing it

From	Sean Wang <sean.wang@mediatek.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH 2/5] nvmem: mtk-efuse: use stack for nvmem_config instead of malloc'ing it
Date	2017-09-22 06:10 +0200
Message-ID	<usnrP-1uE-5@gated-at.bofh.it> (permalink)
References	<uowDn-3I9-5@gated-at.bofh.it> <uowDn-3I9-3@gated-at.bofh.it> <urQcx-5vV-15@gated-at.bofh.it> <urZfP-34T-1@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

Hi, Masahiro

On Thu, 2017-09-21 at 11:09 +0900, Masahiro Yamada wrote:
> Hi Sean,
> 
> 
> 2017-09-21 1:32 GMT+09:00 Sean Wang <sean.wang@mediatek.com>:
> > Hi, Masahiro
> >
> > For maintainability, I felt it's better if we use the same way to
> > register nvmem as that most drivers does under nvmem usually using
> > static structure. Otherwise, they should also be changed to use the
> > one-time data in stack to avoid extra bytes to keep them.
> >
> >         Sean
> 
> 
> Srinivas and I discussed the best practice for allocating nvmem_config.
> https://lkml.org/lkml/2017/9/11/4
> 
> From the discussion, static structure is possible only when
> the system has one instance of the device.
> 

thank you for your detailed explanation

> If you know this is the case for mediatek,
> yes, you can turn it into static,
> but it is not always possible.
> For example, Socionext SoCs have
> two banks of efuse devices.
> 

there should be only one instance of nvmem for mediatek soc, currently


> So, if we want to align the coding style for consistency,
> nvmem in stack is safe and efficient, I think.
> 
> 
> Moving one-time data into stack slightly
> reduces the kernel image size.
> 
> 

agreed on those statements, indeed bigger struct uart_8250_port is still
used on stack for configuring in a lot 8250 driver, so 

Acked-by: Sean Wang <sean.wang@mediatek.com>

Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

[PATCH 2/5] nvmem: mtk-efuse: use stack for nvmem_config instead of malloc'ing it Masahiro Yamada <yamada.masahiro@socionext.com> - 2017-09-11 15:10 +0200
  Re: [PATCH 2/5] nvmem: mtk-efuse: use stack for nvmem_config  instead of malloc'ing it Sean Wang <sean.wang@mediatek.com> - 2017-09-20 18:40 +0200
    Re: [PATCH 2/5] nvmem: mtk-efuse: use stack for nvmem_config instead  of malloc'ing it Masahiro Yamada <yamada.masahiro@socionext.com> - 2017-09-21 04:20 +0200
      Re: [PATCH 2/5] nvmem: mtk-efuse: use stack for nvmem_config  instead of malloc'ing it Sean Wang <sean.wang@mediatek.com> - 2017-09-22 06:10 +0200

csiph-web