On Friday 06 November 2015 08:28 AM, Sukadev Bhattiprolu wrote: > Peter Zijlstra [pet...@infradead.org] wrote: > | On Thu, Nov 05, 2015 at 02:16:15AM +0530, Madhavan Srinivasan wrote: > | > Second patch updates struct arch_misc_reg for arch/powerpc with pmu > registers > | > and adds offsetof macro for the same. It extends perf_reg_value() > | > to use reg idx to decide on struct to return value from. > | > | Why; what's in those regs? > > Those are PMU control registers/counters (in Patch 2) that are of > interest only in the context of a PMU interrupt and not relevant > to ptrace itself.
Yes. Thats right. > Could we add those registers to 'struct pt_regs' anyway? I would prefer not to. Since as you mentioned, these are not relevant to ptrace. Currently patch 2, adds only few pmu registers, but would like to include more. > We do have 'struct perf_regs' but that seems to be arch nuetral. > If architectures could override that, maybe we could add these > new registers there without touching 'struct pt_regs'. Exactly, idea here is to capture more data using perf_sample_reg_intr without extending pt_regs structure. Maddy > Even so, lot of perf code depends on 'struct pt_regs'. > > Sukadev -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
