lkml.org 
[lkml]   [2010]   [Jul]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
DateTue, 27 Jul 2010 10:51:55 -0700
FromCorey Ashford <>
SubjectRe: [RFC][PATCH v1 02/15] perf: export generic hardware events via sysfs
On 07/27/2010 01:27 AM, Robert Richter wrote:
> On 26.07.10 22:18:23, Lin Ming wrote:
>
>>>> /sys/devices/system/cpu/cpu0/events
>>>> |-- L1-dcache-load-misses
>>>> | |-- config
>>>> | `-- type
>
> vs.
>
>>> |-- L1-dcache-load-misses ===> event name
>>> | `-- id ===> event id
>
>>> This is very simple and flexible and solves the original problem too.
>>
>> Yeah, this is flexible. I'll think about this closely.
>
> The thing is, if you start introducing the config/type i/f, we will
> stick with it for a long time. I want to avoid this from the
> beginning.
>
> Using an id only would work with your current implementation too, you
> only need to maintain an id -> config/type mapping, maybe in some
> private data section, without exporting it to userspace.

Now that I understand that the sysfs id essentially points to a kernel
data structure, I like this idea a lot. Before I was thinking that you
were trying to place a lot of info into the id itself.

The only downside I see, and maybe it's a very minor one, is that you'll
no longer have the ability to specify an event without specifying a
sysfs path... there's no other mechanism.

- Corey



\
 
 \ /
  Last update: 2010-07-27 19:55    [from the cache]
©2003-2010