lkml.org 
[lkml]   [2021]   [Feb]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC] IRQ handlers run with some high-priority interrupts(not NMI) enabled on some platform
On Sat, Feb 20, 2021 at 05:32:30PM +1100, Finn Thain wrote:
> Nope. Interrupt priority masking is there to place an upper bound
> interrupt latency. That's why this feature is shipping in contemporary
> hardware (e.g. ARM GIC). If you care about real time workloads on arm64,
> that may interest you.

I don't know if it's still true today, but in the past there was a very
noticeable difference in timer stability between the 68k macintosh
models with the timer interrupt at IPL 1 as compared to the models
where the timer interrupt was at IPL 6. The ability to preempt the
other interrupt handlers made the difference between a usable clock
and one that was pretty unreliable.

Brad Boyer
flar@allandria.com

\
 
 \ /
  Last update: 2021-02-20 08:10    [W:0.195 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site