On Fri, May 17, 2013 at 4:55 PM, Will Deacon <will.dea...@arm.com> wrote: > > So it's still the morning and I haven't had my coffee yet, but I'm really > struggling to see what you're getting at. Why does this have anything to do > with perf?
I don't know, and I just report it out, :-) I found the problem days ago, and until yesterday I had one more hours to git-bisect it, but the result is very frustrated. > >> [1], 'perf top' mistaken output >> Samples: 17K of event 'cpu-clock', Event count (approx.): 3516532661 >> 97.51% [smsc95xx] [k] 0x013645b8 >> 0.21% libc-2.15.so [.] strstr >> 0.14% libc-2.15.so [.] strchr >> 0.12% libc-2.15.so [.] strcmp > > [...] > >> [2], 'perf top' correct output >> Samples: 46K of event 'cpu-clock', Event count (approx.): 937128704 >> 96.44% [kernel] [k] cpuidle_enter_state >> 0.19% libc-2.15.so [.] strstr >> 0.16% [kernel] [k] kallsyms_expand_symbol.clone.0 >> 0.13% [kernel] [k] _raw_spin_unlock_irq > > [...] > > Are you saying that the profile you're seeing is radically different, > rather than there being some formatting error that I can't spot? If so, that Yes. > sounds really strange and I can't see how the patch you mention is to > blame... > > If we want to persue this, I guess other obvious questions are: which kernel > are you running? Does this affect multiple architectures (your diff only Either 3.10-rc1 or today's -next tree(3.10.0-rc1-next-20130516). > changes ARM)? What's the workload which you are profiling? I only tested it on Pandaboard, and no real workload, so you can see cpuidle_enter_state is the top frequent symbol. Or could anyone else try to verify the problem on their own environment? Thanks, -- Ming Lei -- 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/
