lkml.org 
[lkml]   [2019]   [Mar]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [RFC] On the Current Troubles of Mainlining Loongson Platform Drivers
Date
On Mar  7, 2019, Aaro Koskinen <aaro.koskinen@iki.fi> wrote:

> Hi,
> On Thu, Mar 07, 2019 at 03:41:01AM -0300, Alexandre Oliva wrote:
>> On Feb 17, 2019, "Maciej W. Rozycki" <macro@linux-mips.org> wrote:
>>
>> > Is there an MMIO completion barrier missing there somewhere by any chance
>> > causing an IRQ that has been handled already to be redelivered because an
>> > MMIO write meant to clear the IRQ at its origin at handler's completion
>> > has not reached its destination before interrupts have been reenabled in
>> > the issuing CPU? Just a thought.
>>
>> I've finally got a chance to bisect the IRQ14 (nobody cared) regression
>> on my yeeloong. It took me to MIPS: Enforce strong ordering for MMIO
>> accessors (commit 3d474dacae72ac0f28228b328cfa953b05484b7f).

> This is interesting, thanks for the research, but I'm afraid it doesn't seem
> to be the root cause.

Oh, I didn't mean to offer anything definitive, just to report the
findings of my investigation so far, since I had no clue when I'd find
another significant time slot to get back onto it.

> Could you check your /proc/interrupts counters after the boot with
> your change?

16k to 18k interrupts after booting up into multi-user mode, including
some idle time (and possibly anacron jobs) in the case that got more
interrupts. That's not unlike what I get with 4.19.26-gnu.

--
Alexandre Oliva, freedom fighter https://FSFLA.org/blogs/lxo
Be the change, be Free! FSF Latin America board member
GNU Toolchain Engineer Free Software Evangelist
Hay que enGNUrecerse, pero sin perder la terGNUra jamás-GNUChe

\
 
 \ /
  Last update: 2019-03-07 22:24    [W:0.111 / U:0.032 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site