Re: [PATCH 3/4] perf/POWER7: Make event translations available in sysfs

[Jiri Olsa <jolsa@redhat.com>]

On Fri, Nov 16, 2012 at 11:35:37AM -0800, Sukadev Bhattiprolu wrote:
> Jiri Olsa [jolsa@redhat.com] wrote:
> | > 
> | > Can we remove the assumption that the event id is a generic event that
> | > has PERF_COUNT_HW_ prefix and also let the architectures pass in a "show"
> | > function ? This would allow architectures to display any arch specific
> | > events that don't yet have a generic counterpart.
> | > 
> | > IOW, can we do something like this (untested) and make PERF_EVENT_ATTR global:
> | 
> | hm, then you probably can use following:
> | 
> | http://www.spinics.net/lists/kernel/msg1434233.html
> 
> For now, power events can simply be u64 - so am hoping to have something
> like this and replace the raw codes:
> 
> #define PM_CYC			0x1e
> #define PM_GCT_NOSLOT_CYC	0x100f8
> 
> EVENT_ATTR_STR() is interesting, but would require new/extra macros like
> 
> #define PM_CYC_STR		"0x1e"
> #define PM_GCT_NOSLOT_CYC_STR	"0x100f8"
> 
> I went down the path we discussed earlier - to have x86 and Power share
> the EVENT_ATTR() macros. This is making the x86 code less concise
> 
> 	EVENT_ATTR(cpu-cycles,	CPU_CYCLES)
> 
> becomes
> 
> 	EVENT_ATTR(cpu-cycles,	PERF_COUNT_HW_CPU_CYCLES, events_sysfs_show)
> 
> with each EVENT_ATTR() explcitly adding events_sysfs_show or needing another
> wrapper around the wrappers.
> 
> Still tweaking it, but would it be flexible to make 'struct pmu_events_attr'
> common and let architectures define the EVENT_ATTR() as needed ? Would
> duplicate some code but hopefully not a lot.

sounds good, let's see ;)

jirka