Re: [PATCH V8 08/25] perf tools: Add Intel BTS support

From: Arnaldo Carvalho de Melo
Date: Mon Aug 17 2015 - 13:58:47 EST


Em Mon, Aug 17, 2015 at 08:43:09PM +0300, Adrian Hunter escreveu:
> On 17/08/2015 6:52 p.m., Arnaldo Carvalho de Melo wrote:
> > 1.92% usleep [unknown] [.] 0x00007fa0ff695086
> > 1.60% usleep [unknown] [.] 0xffffffff811c91d0
> > 1.48% usleep [unknown] [.] 0x00007fa0ffb3030d
> > 1.24% usleep [unknown] [.] 0x00007fa0ff6950c7

> It is very weird that it doesn't know the dso.

> I presume there is nothing unusual about the environment e.g. in a chroot or anything

> What if you try a different event e.g. perf record --per-thread -e cycles sleep 1

[root@zoo ~]# perf record --per-thread -e cycles sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.014 MB perf.data (9 samples) ]
[root@zoo ~]# perf report | grep -v ^# | head -5
42.57% sleep libc-2.20.so [.] malloc_hook_ini
41.81% sleep [kernel.vmlinux] [k] filemap_fault
14.35% sleep [kernel.vmlinux] [k] flush_tlb_mm_range
1.18% sleep [kernel.vmlinux] [k] strlcpy
0.09% sleep [kernel.vmlinux] [k] native_write_msr_safe
[root@zoo ~]#

[root@zoo ~]# perf report --dsos libc-2.20.so | grep -v '^[#]'
42.57% sleep [.] malloc_hook_ini


[root@zoo ~]#

[root@zoo ~]# perf record --per-thread -e intel_bts// usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.825 MB perf.data ]
[root@zoo ~]# perf report | grep -v ^# | head -5
Warning:
79074 instruction trace errors




2.80% usleep [unknown] [.] 0x00007f48888aa061
[root@zoo ~]#

- Arnaldo
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