[PATCH 0/4] perf_event: introduce 'perf timer' to analyze timer's behavior

Xiao Guangrong
2009-12-15T11:18:53Z

Hi,

We introduce 'perf timer' in this patchset, it can analyze timer
latency and timer function handle time, the usage and result is
like below:

# perf timer record
# perf timer lat --print-lat --print-handle
-------------------------------------------------------------------------------------------------------
| Timer | TYPE | Avg-latency | Max-latency | Max-latency-at-TS |Max-lat-at-Task |
|0xf7ad1f5c |hrtimer |996068.500 ns|1607650 ns|10270128658526 |init |
|0xf7903f04 |timer |0.625 HZ|2 HZ|10270344082394 |swapper |
|0xf787a05c |hrtimer |200239.500 ns|359929 ns|10269316024808 |main |
|main :[ PROF]|itimer |0.000 HZ|0 HZ|10237021270557 |main |
|main :[VIRTUAL]|itimer |0.000 HZ|0 HZ|10257314773501 |main |

......

-------------------------------------------------------------------------------------------------------
| Timer | TYPE | Avg-handle (ms)|Max-handle(ms)| Max-handle-at-TS(s)|Max-lat-at-func |
|0xf7ad1f5c |hrtimer |0.025 |0.025 |10270.129 |0xc016b5b0 |
|0xf7903f04 |timer |0.009 |0.011 |10260.342 |0xc0159240 |
|0xf787a05c |hrtimer |0.031 |0.062 |10267.018 |0xc014cc40 |

And, in current code, it'll complain with below message when we use
'perf timer lat':

# ./perf timer lat
Warning: unknown op '{'
Warning: Error: expected type 5 but read 1
Warning: failed to read event print fmt for hrtimer_start
Warning: unknown op '{'
Warning: Error: expected type 5 but read 1
Warning: failed to read event print fmt for hrtimer_expire_entry

It's because perf parse "hrtimer_start" and "hrtimer_expire_entry" fail,
but it not hurt using.

See: http://lkml.org/lkml/2009/10/12/726

include/trace/events/timer.h | 8
tools/perf/Documentation/perf-timer.txt | 40 +
tools/perf/Makefile | 1
tools/perf/builtin-sched.c | 3
tools/perf/builtin-timer.c | 954 ++++++++++++++++++++++++++++++++
tools/perf/builtin.h | 1
tools/perf/command-list.txt | 1
tools/perf/perf.c | 1
tools/perf/util/trace-event-parse.c | 25
tools/perf/util/trace-event.h | 4
10 files changed, 1030 insertions(+), 8 deletions(-)