lkml.org 
[lkml]   [2003]   [Sep]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] Make futex waiters take an mm or inode reference

On Mon, 8 Sep 2003, Jamie Lokier wrote:
>
> This patch makes each futex waiter hold a reference to the mm or inode
> that a futex is keyed on.

I get the inode part, but let's think about the mm part a bit more.

In particular, passing off a futex that points to private memory to
somebody else just _doesn't_work_. It's insane. So I'd suggest saying that
an anonymous futex is only an <address,offset> pair, and drop the "mm"
entirely. Let's make an anonymous futex _really_ anonymous, and document
that it's only an "address" - passing it off via UNIX domain sockets is
fine, it just doesn't do anything useful.

So is there any reason to really having "private.mm" AT ALL? From what I
can tell, it is not actually ever used (all "mm" users are "current->mm"),
so I don't see the point of incrementing a count for it either.

Or did I miss something?

Linus

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2009-11-18 23:46    [W:0.556 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site