On Tue, Sep 10, 2013 at 4:06 AM, Michael Ellerman <mich...@ellerman.id.au> wrote: > > On Fri, 2013-08-30 at 09:54 +0530, Anshuman Khandual wrote: > > This patchset is the re-spin of the original branch stack sampling > > patchset which introduced new PERF_SAMPLE_BRANCH_COND filter. This patchset > > also enables SW based branch filtering support for PPC64 platforms which > > have > > branch stack sampling support. With this new enablement, the branch filter > > support > > for PPC64 platforms have been extended to include all these combinations > > discussed > > below with a sample test application program. > > ... > > > Mixed filters > > ------------- > > (6) perf record -e branch-misses:u -j any_call,any_ret ./cprog > > Error: > > The perf.data file has no samples! > > > > NOTE: As expected. The HW filters all the branches which are calls and SW > > tries to find return > > branches in that given set. Both the filters are mutually exclussive, so > > obviously no samples > > found in the end profile. > > The semantics of multiple filters is not clear to me. It could be an OR, > or an AND. You have implemented AND, does that match existing behaviour > on x86 for example? > The semantic on the API is OR. AND does not make sense: CALL & RETURN? On x86, the HW filter is an OR (default: ALL, set bit to disable a type). I suspect it is similar on PPC.
> > cheers > > -- 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/