lkml.org 
[lkml]   [2019]   [Jun]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: rcu_read_lock lost its compiler barrier
On Tue, 4 Jun 2019, Linus Torvalds wrote:

> So I don't technically disagree with anything you say,

That's good to know!

> I just wanted
> to point out that as far as the kernel is concerned, we do have higher
> quality expectations from the compiler than just "technically valid
> according to the C standard".

Which suggests asking whether these higher expectations should be
reflected in the Linux Kernel Memory Model. So far we have largely
avoided doing that sort of thing, although there are a few exceptions.

(For example, we assume the compiler does not destroy address
dependencies from volatile reads -- but we also warn that this
assumption may fail if the programmer does not follow some rules
described in one of Paul's documentation files.)

Alan

\
 
 \ /
  Last update: 2019-06-04 19:01    [W:0.201 / U:5.884 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site