[PATCH v3 4/4] printk/nmi: Increase the size of NMI buffer and make it configurable
geert at linux-m68k.org
Fri Dec 11 04:50:16 PST 2015
On Fri, Dec 11, 2015 at 1:41 PM, Petr Mladek <pmladek at suse.com> wrote:
> On Fri 2015-12-11 12:10:02, Geert Uytterhoeven wrote:
>> On Wed, Dec 9, 2015 at 2:21 PM, Petr Mladek <pmladek at suse.com> wrote:
>> > --- a/init/Kconfig
>> > +++ b/init/Kconfig
>> > @@ -866,6 +866,28 @@ config LOG_CPU_MAX_BUF_SHIFT
>> > 13 => 8 KB for each CPU
>> > 12 => 4 KB for each CPU
>> > +config NMI_LOG_BUF_SHIFT
>> > + int "Temporary per-CPU NMI log buffer size (12 => 4KB, 13 => 8KB)"
>> > + range 10 21
>> > + default 13
>> > + depends on PRINTK && HAVE_NMI
>> Symbol NMI_LOG_BUF_SHIFT does not exist if its dependencies are not met.
> Åh, the NMI buffer is enabled on arm via NEED_PRINTK_NMI.
> The buffer is compiled when CONFIG_PRINTK_NMI is defined. I am going
> to fix it the following way:
> diff --git a/init/Kconfig b/init/Kconfig
> index efcff25a112d..61cfd96a3c96 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -870,7 +870,7 @@ config NMI_LOG_BUF_SHIFT
> int "Temporary per-CPU NMI log buffer size (12 => 4KB, 13 => 8KB)"
> range 10 21
> default 13
> - depends on PRINTK && HAVE_NMI
> + depends on PRINTK_NMI
> Select the size of a per-CPU buffer where NMI messages are temporary
> stored. They are copied to the main log buffer in a safe context
Makes sense, as kernel/printk/nmi.c is compiled if PRINTK_NMI is set.
Acked-by: Geert Uytterhoeven <geert+renesas at glider.be>
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
More information about the linux-arm-kernel