Re: [PATCH] CMWQ: Set workqueue name before we process one work.

[Tejun Heo <tj@kernel.org>]

On 08/16/2010 09:39 AM, Tao Ma wrote:
> Now in CMWQ, workqueue threads are named as 'kworker/*'. So it is
> a little boring to see in the 'top'(below) and actually it isn't
> meaningful for the users.
> 12606 root      20   0     0    0    0 S    2  0.0   0:03.22 kworker/u:0
> 12607 root      20   0     0    0    0 S    1  0.0   0:03.69 kworker/u:4
> 
> So this patch just try to set the proper workqueue name if it does
> exist. Yes, workqueue now is a thread pool and the data may be not
> accurate but I think it is better(below) than the 'kworker*' stuff.
> And if there is something block the workqueue, we can find the caller
> easily.
> 12606 root      20   0     0    0    0 D    2  0.0   0:02.90 dlm_wq
> 12607 root      20   0     0    0    0 D    0  0.0   0:03.21 ocfs2_wq
> 
> What's more, in ocfs2, we sometimes want to print some debug info in
> the system log and we use 'current->comm' to print the thread and this
> change also does help.
> 
> The only thing I am not clear is that do we need [gs]et_task_comm?
> I guess not and this patch just try to use strlcpy without task_lock.
> 
> Cc: Tejun Heo <tj@kernel.org>
> Signed-off-by: Tao Ma <tao.ma@oracle.com>

I thought about the same thing but this doesn't provide any more
information than stack traces for debugging and for run time tracking
implementing tracing API (scheduled to be added in this devel cycle)
is the right approach.  Also, I don't think it's wise to constantly
change program name.  It will confuse more than help.  So, unless
there are other reasons for doing this, I don't think I'm gonna take
this one.

Thanks.

-- 
tejun