Re: [PATCH v2 2/2] sched/numa: Add tracepoint that tracks the skipping of numa balancing due to cpuset memory pinning

[Libo Chen <libo.chen@oracle.com>]

On 3/27/25 07:03, Steven Rostedt wrote:
> On Wed, 26 Mar 2025 21:32:32 -0700
> Libo Chen <libo.chen@oracle.com> wrote:
> 
>> On 3/26/25 19:06, Steven Rostedt wrote:
>>> On Wed, 26 Mar 2025 17:40:02 -0700
>>> Libo Chen <libo.chen@oracle.com> wrote:
>>>   
>>>>> +	TP_printk("comm=%s pid=%d tgid=%d ngid=%d mem_node_allowed_mask=%lx",    
>>>>
>>>>
>>>> I cannot find a way to print out nodemask_t nicely here with %*pbl.
>>>> So I fall back to just raw hex value. Will be grateful if someone
>>>> knows a better way to print nodemask nicely in a tracepoint    
>>>
>>> Ug.
>>>
>>> I guess I need to add support for that. Both in the boot verifier as well
>>> as in libtraceevent.
>>>   
>>
>> That will be fantastic, I think this is quite useful.
>

Oops just saw this right now, not sure how I missed it.
 
> I'm curious to what was broken. Just the user space side? Or was the kernel
> side broken too?
> 

That's a good point, I originally only tried %*pbl with trace-cmd, but I
tested your patch without trace-cmd. So yeah %*pbl may already be working in
the kernel, I will report back later today.

-- Libo

> I notice that i2c_write has "[%*phD]" which means it worked, and also
> skipped out on the verification tests. This should be fixed.
> 
> But trace-cmd and perf will not be able to print that out either.
> 
> Now %*pbl works in the kernel (not checked), but probably doesn't work for
> trace-cmd.
> 
> -- Steve