Re: [PATCH 0/7] ndctl: cxl: add monitor support for trace events

[Dave Jiang <dave.jiang@intel.com>]

On 9/22/2022 7:21 AM, Jonathan Cameron wrote:
> On Wed, 14 Sep 2022 13:47:49 -0700
> Dave Jiang <dave.jiang@intel.com> wrote:
>
>> This patch series for ndctl implements the monitor command for the cxl tool.
>> The initial implementation will collect CXL trace events emitted by the
>> kernel. libtraceevent and libtracefs will be used to parse the trace
>> event buffer. The monitor will pend on an epoll fd and wait for new event
>> entries to be posted. The output will be in json format. By default the events
>> are emitted to stdio, but can also be logged to a file. Each event is converted
>> to a JSON object and logged as such. All the fields exported are read by the
>> monitor code and added to the JSON object.
> Hi Dave,
>
> FYI, I just wanted to mention that we will be aiming to duplicate a bunch
> of this functionality in rasdaemon.
>
> As that is handling the equivalent of many of these events on our systems
> from other components we don't want to grab the data via alternative tooling
> and then have to merge it later.
>
> Absolutely not a problem to have it in this tool as well. I mostly wanted
> to raise it because longer term we'll need to be careful to test with both
> solutions if there are any changes to what they are being sent.

Thanks for the heads up Jonathan!


>
> Thanks,
>
> Jonathan
>
>> ---
>>
>> Dave Jiang (7):
>>        ndctl: cxl: add helper function to parse trace event to json object
>>        ndctl: cxl: add helper to parse through all current events
>>        ndctl: cxl: add common function to enable event trace
>>        ndctl: cxl: add common function to disable event trace
>>        ndctl: cxl: add monitor function for event trace events
>>        ndctl: cxl: add logging functions for monitor
>>        ndctl: cxl: add monitor command to cxl
>>
>>
>>   cxl/builtin.h     |   1 +
>>   cxl/cxl.c         |   1 +
>>   cxl/event_trace.c | 236 ++++++++++++++++++++++++++++++++++++++++++++++
>>   cxl/event_trace.h |  23 +++++
>>   cxl/meson.build   |   4 +
>>   cxl/monitor.c     | 235 +++++++++++++++++++++++++++++++++++++++++++++
>>   meson.build       |   3 +
>>   7 files changed, 503 insertions(+)
>>   create mode 100644 cxl/event_trace.c
>>   create mode 100644 cxl/event_trace.h
>>   create mode 100644 cxl/monitor.c
>>
>> --
>>