Re: [PATCH 4/6 -tip] perf_counter: Add Generalized Hardware interrupt support for AMD

Ingo Molnar
2009-07-01T11:24:53Z

* Jaswinder Singh Rajput <jaswinder@kernel.org> wrote:

>
> $ ./perf stat -e interrupts -e masked -e int-pending-mask-cycles -- ls -lR /usr/include/ > /dev/null
>
> Performance counter stats for 'ls -lR /usr/include/':
>
> 377 interrupts
> 53429936 int-mask-cycles
> 1119 int-pending-mask-cycles
>
> 0.371457539 seconds time elapsed

Agreed, this is another useful generalization - and the 'cycles
pending' metrics are not retrievable via any software means.

We could and should probably add a software counter for hardirqs as
wel. That would allow the vector/irqnr information to be passed in,
and it would allow architectures without irq metrics in the PMU to
have this counter too.

This way we could profile based on a specific interrupt source only
- say based on the networking card.

Ingo