lkml.org 
[lkml]   [2021]   [Feb]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: tasks-trace RCU: question about grace period forward progress
On Thu, Feb 25, 2021 at 11:23:18PM +0100, Peter Zijlstra wrote:
> On Thu, Feb 25, 2021 at 10:33:21AM -0800, Paul E. McKenney wrote:
> > One question for Peter... Does each and every context switch imply a
> > full barrier?
>
> Yes, also see the smp_mb__after_spinlock() in __schedule() :-)

Whew!!! ;-)

Yeah, I could make RCU Tasks Trace deal with lack of a full barrier in
that case, but I would rather not... I could imagine optimizing so
that the full barrier happened only when tasks migrated, but I could
also imagine a world of hurt stemming from such an optimization!

Thanx, Paul

\
 
 \ /
  Last update: 2021-02-26 00:06    [W:0.049 / U:0.108 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site