Re: + prctl-add-pr_set_proctitle_area-option.patch added to -mmtree

From: Timo Sirainen
Date: Tue Nov 10 2009 - 13:00:29 EST


On Wed, 2009-11-11 at 02:48 +0900, KOSAKI Motohiro wrote:
> There is unwritten reason. I hope to add /proc/[pid]/cmdline cache. It
> help to avoid
> ps getting stuck by mmap_sem.

Can you explain this further? When would it cache the value and when
would it be returned? I was at least hoping to avoid calling prctl()
every time when I want process title changed.

I think Solaris saves the first 80 chars of the initial cmdline to
kernel memory and gives that to ps. I guess doing something similar and
returning it only when userspace memory can't be accessed would be ok.

Attachment: signature.asc
Description: This is a digitally signed message part