Re: [RFC PATCH v2 5/5] docs: ABI: Add sysfs documentation interface of hardware prefetch driver

From: Dave Hansen
Date: Sun Nov 07 2021 - 20:49:22 EST


On 11/7/21 5:29 PM, tarumizu.kohei@xxxxxxxxxxx wrote:
>> How does this look in practice?
> It works on a x86 machine is shown below:
>
> # find /sys/devices/system/cpu/cpu0/hwpf/
> /sys/devices/system/cpu/cpu0/hwpf/
> /sys/devices/system/cpu/cpu0/hwpf/l2
> /sys/devices/system/cpu/cpu0/hwpf/l2/enable
> /sys/devices/system/cpu/cpu0/hwpf/l1
> /sys/devices/system/cpu/cpu0/hwpf/l1/enable
>
>> Dumb question, but why don't we give these things names? If the Intel one is
>> called "L2 Hardware Prefetcher Disable", couldn't the directory be "l2_prefetch"?
> There is no specific reason for directory names. We named it "l*"
> because it is related to a certain cache level. We would change it,
> if there is another suitable name.

Ahh, so you really do intend the l2 directory to be for *all* the L2
prefetchers? I guess that's OK, but will folks ever want to do "L2
Hardware Prefetcher Disable", but not "L2 Adjacent Cache Line Prefetcher
Disable"?