On 6/28/22 15:33, Peter Xu wrote:
The key point is the connection between "locked" and killable. If the comment
explained why "locked" means "killable", that would help clear this up. The
NOWAIT sentence is also confusing to me, and adding "mostly NOWAIT" does not
clear it up either... :)
Sorry to have a comment that makes it feels confusing. I tried to
explicitly put the comment to be after setting FAULT_FLAG_KILLABLE but
obviously I didn't do my job well..
Maybe that NOWAIT thing adds more complexity but not even necessary.
Would below one more acceptable?
/*
* We'll only be able to respond to signals when "locked !=
* NULL". When with it, we'll always respond to SIGKILL
* (as implied by FAULT_FLAG_KILLABLE above), and we'll
* respond to non-fatal signals only if the GUP user has
* specified FOLL_INTERRUPTIBLE.
*/
It looks like part of this comment is trying to document a pre-existing
concept, which is that faultin_page() only ever sets FAULT_FLAG_KILLABLE
if locked != NULL. The problem I am (personally) having is that I don't
yet understand why or how those are connected: what is it about having
locked non-NULL that means the process is killable? (Can you explain why
that is?)
If that were clear, I think I could suggest a good comment wording.
thanks,
--
John Hubbard
NVIDIA
