Hi Arnaldo, On Tue, 6 Nov 2012 17:52:21 -0300, Arnaldo Carvalho de Melo wrote: > Em Mon, Nov 05, 2012 at 02:50:47PM +0100, Stephane Eranian escreveu: > [root@sandy acme]# perf mem -t load rep --stdio > --sort=symbol,symbol_daddr,cost > # Samples: 30 of event 'cpu/mem-loads/pp' > # Total cost : 640 > # Sort order : symbol,symbol_daddr,cost > # > # Overhead Samples Symbol Data Symbol > Cost > # ........ ........... ...................... ...................... > ....... > # > 55.00% 1 [k] lookup_fast [k] 0xffff8803b7521bd4 > 352 > 5.47% 1 [k] cache_alloc_refill [k] 0xffff880407705024 > 35 > 3.44% 1 [k] cache_alloc_refill [k] 0xffff88041d8527d8 > 22 > 3.28% 1 [k] run_timer_softirq [k] 0xffff88041e2c3e90 > 21 > 2.50% 1 [k] __list_add [k] 0xffff8803b7521d68 > 16 > 2.19% 1 [.] __strcoll_l [.] 0x00007fffa8d44080 > 14 > 1.88% 1 [.] __strcoll_l [.] 0x00007fffa8d44104 > 12 > > If we go to the annotation browser to see where is that lookup_fast hitting > we get: > > 100.00 │ mov -0x34(%rbp),%eax > > How to map 0xffff8803b7521bd4 to a stack variable, struct members and all? > > Humm, for userspace we have PERF_SAMPLE_REGS_USER for the dwarf unwinder we > need for userspace, but what about reverse mapping of kernel variables? Jiri?
I suspect there aren't much thing we can do on stack. One thing we can do is adding dso_daddr to sort key and seeing it's a [stack] (or [stack:tid]) or not. But not sure it can be done for kernel stacks too. Thanks, Namhyung -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
