On Tue, 23 Jan 2024 09:49:00 -0500
Steven Rostedt [off-list ref] wrote:

On Tue, 23 Jan 2024 18:23:58 +0800
Huang Yiwei [off-list ref] wrote:

quoted

quoted

And if we really want to be fancy!

	ftrace_dump_on_opps[=orig_cpu | =<instance> | =orig_cpu:<instance> ][,<instance> | ,<instance>:orig_cpu]
    

Yeah, I agree to make the parameter more flexible.

"=orig_cpu:<instance>" means to dump global and another instance?  

No, I added a comma for that:

  =,orig_cpu:<instance>

Would mean to dump all of global and just the origin CPU of the instance.

quoted

I'm thinking of the following format:

ftrace_dump_on_opps[=orig_cpu | =<instance>][,<instance> | 
,<instance>=orig_cpu]

Here list some possible situations:

1. Dump global on orig_cpu:
ftrace_dump_on_oops=orig_cpu

2. Dump global and instance1 on all cpu, instance2 on orig_cpu:
ftrace_dump_on_opps,<instance1>,<instance2>=orig_cpu

3. Dump global and instance1 on orig_cpu, instance2 on all cpu:
ftrace_dump_on_opps=orig_cpu,<instance1>=orig_cpu,<instance2>

4. Dump instance1 on all cpu, instance2 on orig_cpu:
ftrace_dump_on_opps=<instance1>,<instance2>=orig_cpu

5. Dump instance1 and instance2 on orig_cpu:
ftrace_dump_on_opps=<instance1>=orig_cpu,<instance2>=orig_cpu

This makes orig_cpu dump for global same as instance, the parameter may 
seems more unified and users don't need to remember another markers to 
request orig_cpu dump.

But one problem here is if there's an instance named "orig_cpu", then we 
may not dump it correctly.  

I would put that under:

   Patient: Doctor it hurts me when I do this
   Doctor:  Then don't do that

;-)

Oh, and I'm fine with what you proposed above.

-- Steve