d37ba88059
Before this patch we can see very large time in the events before the 'bpf-output' event. For example: # perf trace -vv -T --ev sched:sched_switch \ --ev bpf-output/no-inherit,name=evt/ \ --ev ./test_bpf_trace.c/map:channel.event=evt/ \ usleep 10 ... 18446744073709.551 (18446564645918.480 ms): usleep/4157 nanosleep(rqtp: 0x7ffd3f0dc4e0) ... 18446744073709.551 ( ): evt:Raise a BPF event!..) 179427791.076 ( ): perf_bpf_probe:func_begin:(ffffffff810eb9a0)) 179427791.081 ( ): sched:sched_switch:usleep:4157 [120] S ==> swapper/2:0 [120]) ... We can also see the differences between bpf-output events and breakpoint events: For bpf output event: sample_type IP|TID|RAW|IDENTIFIER For tracepoint events: sample_type IP|TID|TIME|CPU|PERIOD|RAW|IDENTIFIER This patch fix this differences by adding more sample type for bpf-output events. After this patch: # perf trace -vv -T --ev sched:sched_switch \ --ev bpf-output/no-inherit,name=evt/ \ --ev ./test_bpf_trace.c/map:channel.event=evt/ \ usleep 10 ... 179877370.878 ( 0.003 ms): usleep/5336 nanosleep(rqtp: 0x7ffff866c450) ... 179877370.878 ( ): evt:Raise a BPF event!..) 179877370.878 ( ): perf_bpf_probe:func_begin:(ffffffff810eb9a0)) 179877370.882 ( ): sched:sched_switch:usleep:5336 [120] S ==> swapper/4:0 [120]) 179877370.945 ( ): evt:Raise a BPF event!..) ... # ./perf trace -vv -T --ev sched:sched_switch \ --ev bpf-output/no-inherit,name=evt/ \ --ev ./test_bpf_trace.c/map:channel.event=evt/ \ usleep 10 2>&1 | grep sample_type sample_type IP|TID|TIME|ID|CPU|PERIOD|RAW sample_type IP|TID|TIME|ID|CPU|PERIOD|RAW sample_type IP|TID|TIME|ID|CPU|PERIOD|RAW sample_type IP|TID|TIME|ID|CPU|PERIOD|RAW sample_type IP|TID|TIME|ID|CPU|PERIOD|RAW sample_type IP|TID|TIME|ID|CPU|PERIOD|RAW The 'IDENTIFIER' info is not required because all events have the same sample_type. Committer notes: Further testing, on top of the changes making 'perf trace' avoid samples from events without PERF_SAMPLE_TIME: Before: # trace --ev bpf-output/no-inherit,name=evt/ --ev /home/acme/bpf/test_bpf_trace.c/map:channel.event=evt/ usleep 10 <SNIP> 0.560 ( 0.001 ms): brk( ) = 0x55e5a1df8000 18446640227439.430 (18446640227438.859 ms): nanosleep(rqtp: 0x7ffc96643370) ... 18446640227439.430 ( ): evt:Raise a BPF event!..) 0.576 ( ): perf_bpf_probe:func_begin:(ffffffff81112460)) 18446640227439.430 ( ): evt:Raise a BPF event!..) 0.645 ( ): perf_bpf_probe:func_end:(ffffffff81112460 <- ffffffff81003d92)) 0.646 ( 0.076 ms): ... [continued]: nanosleep()) = 0 # After: # trace --ev bpf-output/no-inherit,name=evt/ --ev /home/acme/bpf/test_bpf_trace.c/map:channel.event=evt/ usleep 10 <SNIP> 0.292 ( 0.001 ms): brk( ) = 0x55c7cd6e1000 0.302 ( 0.004 ms): nanosleep(rqtp: 0x7ffedd8bc0f0) ... 0.302 ( ): evt:Raise a BPF event!..) 0.303 ( ): perf_bpf_probe:func_begin:(ffffffff81112460)) 0.397 ( ): evt:Raise a BPF event!..) 0.397 ( ): perf_bpf_probe:func_end:(ffffffff81112460 <- ffffffff81003d92)) 0.398 ( 0.100 ms): ... [continued]: nanosleep()) = 0 Signed-off-by: Wang Nan <wangnan0@huawei.com> Reported-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1459517202-42320-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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.. | ||
arch | ||
bench | ||
config | ||
Documentation | ||
jvmti | ||
python | ||
scripts | ||
tests | ||
trace/strace/groups | ||
ui | ||
util | ||
.gitignore | ||
Build | ||
builtin-annotate.c | ||
builtin-bench.c | ||
builtin-buildid-cache.c | ||
builtin-buildid-list.c | ||
builtin-config.c | ||
builtin-data.c | ||
builtin-diff.c | ||
builtin-evlist.c | ||
builtin-help.c | ||
builtin-inject.c | ||
builtin-kmem.c | ||
builtin-kvm.c | ||
builtin-list.c | ||
builtin-lock.c | ||
builtin-mem.c | ||
builtin-probe.c | ||
builtin-record.c | ||
builtin-report.c | ||
builtin-sched.c | ||
builtin-script.c | ||
builtin-stat.c | ||
builtin-timechart.c | ||
builtin-top.c | ||
builtin-trace.c | ||
builtin-version.c | ||
builtin.h | ||
command-list.txt | ||
CREDITS | ||
design.txt | ||
Makefile | ||
Makefile.perf | ||
MANIFEST | ||
perf-archive.sh | ||
perf-completion.sh | ||
perf-read-vdso.c | ||
perf-sys.h | ||
perf-with-kcore.sh | ||
perf.c | ||
perf.h |