Re: [PATCH] x86: Add a turbo mode sysctl

From: Nikolay Borisov
Date: Mon Apr 04 2016 - 02:48:32 EST




On 04/01/2016 06:49 PM, Andy Lutomirski wrote:
> Sadly, hardware turbo mode buttons are few and far between in these
> degenerate times. Add a software control at /proc/sys/turbo_mode.
>
> Unfortunately, Linux graphical environments have become very
> heavy-weight and are essentially unusable on non-Turbo systems. The
> VT console works very well, though.
>
> Due to KVM limitations, turbo mode is permanently on in a KVM guest.
>
> Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>
> ---
> arch/x86/mm/pat.c | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 61 insertions(+), 2 deletions(-)


The name of the sysctl really sucks, it just control whether caching is
enabled/disabled. Now, having said that I realize there are multiple
sysctl that contain "cache" in their names. But can you come up with a
more descriptive name, directly relating to what the sysctl does and now
what its actual effects are :)? Also, aren't caches enabled by the
kernel when the system is booting, according to SDM1/section 9.3 caches
are disabled after reset and I assume the kernel does enable them when
it's booting?