Re: [PATCH 2/3] printk: Add %ptc to safely print a task's comm

KOSAKI Motohiro
2011-05-18T00:32:37Z

(2011/05/17 6:19), John Stultz wrote:
> Accessing task->comm requires proper locking. However in the past
> access to current->comm could be done without locking. This
> is no longer the case, so all comm access needs to be done
> while holding the comm_lock.
>
> In my attempt to clean up unprotected comm access, I've noticed
> most comm access is done for printk output. To simplify correct
> locking in these cases, I've introduced a new %ptc format,
> which will print the corresponding task's comm.
>
> Example use:
> printk("%ptc: unaligned epc - sending SIGBUS.\n", current);
>
> CC: Ted Ts'o<tytso@mit.edu>
> CC: KOSAKI Motohiro<kosaki.motohiro@jp.fujitsu.com>
> CC: David Rientjes<rientjes@google.com>
> CC: Dave Hansen<dave@linux.vnet.ibm.com>
> CC: Andrew Morton<akpm@linux-foundation.org>
> CC: linux-mm@kvack.org
> Signed-off-by: John Stultz<john.stultz@linaro.org>

Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>