Re: [PATCH v3 0/8] tracing/boot: Add new options for tracing specific period

[Shuah Khan <skhan@linuxfoundation.org>]

On 9/10/20 7:27 PM, Masami Hiramatsu wrote:
> On Thu, 10 Sep 2020 19:34:33 -0400
> Steven Rostedt <rostedt@goodmis.org> wrote:
> 
>> On Thu, 10 Sep 2020 17:54:54 +0900
>> Masami Hiramatsu <mhiramat@kernel.org> wrote:
>>
>>> Hi,
>>>
>>> Here is the 3rd version of the series to improve the boot-time tracing to
>>> support kretprobe and tracing_on option. Previous version is here:
>>>
>>>   https://lkml.kernel.org/r/159894698993.1478826.2813843560314595660.stgit@devnote2
>>>
>>> This version adds uprobe %return suffix support ([5/8]) and the testcases
>>> ([8/8]), and update kprobe %suffix support([4/8]) and the uprobe event
>>> document([6/8]).
>>>
>>>
>>> The combination of tracing_on and kretprobe allows us to trace events
>>> while a specific function call period. For example, the below bootconfig
>>> will make a function callgraph in the pci_proc_init() function at boot
>>> time.
>>>
>>> ftrace {
>>> 	tracing_on = 0  # off at start
>>> 	tracer = function_graph
>>> 	event.kprobes {
>>> 		start_event {
>>> 			probes = "pci_proc_init"
>>> 			actions = "traceon"
>>> 		}
>>> 		end_event {
>>> 			probes = "pci_proc_init%return"
>>> 			actions = "traceoff"
>>> 		}
>>> 	}
>>> }
>>>
>>> Here is the example output;
>>>
>>
>> [..]
>>
>> Hi Masami,
>>
>> This looks really great! I just got back from a 10 day holiday, and I'm
>> drowning in "catch-up".  I plan on looking at all this relatively soon
>> (in a week or two?). I just don't want you to think I'm ignoring this.
> 
> Hi Steve,
> 
> Thanks, I hope you enjoyed the holiday!
> BTW, this series includes some document update and testcases.
> Since we can not decouple these updates, I think it is better you to
> pull the series.
> 

Hi Steve and Masami,

selftests patch 8/8 in this series looks good to me. My ack for
it to go through Steve's ftrace tree

Acked-by: Shuah Khan <skhan@linuxfoundation.org>

thanks,
-- Shuah