[RFD 0/5] Add latency histogram
From: Daniel Wagner
Date: Thu Apr 30 2015 - 06:06:35 EST
I would like to discuss a possible way of getting the feature of the
latecy_hist.patch  added to mainline.
"Latency histograms are primarily relevant in the context of real-time
enabled kernels (CONFIG_PREEMPT/CONFIG_PREEMPT_RT)and are used in the
quality management of the Linux real-time capabilities."
Steven pointed out that this might be doable based on Tom Zanussi's
"[PATCH v4 0/7] tracing: 'hist' triggers" .
Here are my findings. It was not too complicated to get it working,
though I had to add some hacks. I have added comments to each patch.
Daniel Wagner (4):
tracing: Add support to sort on the key
tracing: Add option to quantize key values
tracing: Deference pointers without RCU checks
tracing: Add trace_irqsoff tracepoints
Tom Zanussi (1):
tracing: 'hist' triggers
include/linux/rculist.h | 36 +++++++++++++++++++++++++++++
include/linux/tracepoint.h | 4 ++--
include/trace/events/latency.h | 40 ++++++++++++++++++++++++++++++++
kernel/trace/trace_events_hist.c | 46 +++++++++++++++++++++++++++++++++----
kernel/trace/trace_events_trigger.c | 18 +++++++++------
kernel/trace/trace_irqsoff.c | 38 ++++++++++++++++++++++++++++++
6 files changed, 168 insertions(+), 14 deletions(-)
create mode 100644 include/trace/events/latency.h
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/