Messages in this thread | | | Subject | Re: perf trace + BPF | From | "Wangnan (F)" <> | Date | Fri, 1 Apr 2016 21:29:52 +0800 |
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On 2016/4/1 2:08, Arnaldo Carvalho de Melo wrote: > Hi Wang, > > Trying to get back at working with 'perf trace' + BPF and I'm > noticing that the perf_event_attr->sample_type for the BPF events are > different than the ones for the raw_syscalls:sys_{enter,exit} or to > other tracepoint events we may ask 'perf trace' to set up, for instance, > for: > > perf trace -vv -T --ev sched:sched_switch --ev bpf-output/no-inherit,name=evt/ --ev /home/acme/bpf/test_bpf_trace.c/map:channel.event=evt/ usleep 10 > > We get these sample types (full perf_event_attr dump at the end of this > message): > > sched:sched_switch: > sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER > > [root@jouet ~]# perf probe -l > perf_bpf_probe:func_begin (on SyS_nanosleep@linux/kernel/time/hrtimer.c) > perf_bpf_probe:func_end (on SyS_nanosleep%return@linux/kernel/time/hrtimer.c) > > sample_type IP|TID|RAW|IDENTIFIER > > raw_syscalls:sys_{enter,exit}: > > sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER > > I guess this is an interaction with that "no-inherit" part, probably we need to > set PERF_SAMPLE_TIME by some other means...
Please see [1]. Not related to no-inherit, just because the bpf-output event is not a tracepoint.
And glad to see you restart working on my patches again!
Thank you.
[1] http://lkml.kernel.org/g/1459517202-42320-1-git-send-email-wangnan0@huawei.com
> - Arnaldo >
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