Date:   Fri, 3 Mar 2023 19:11:09 -0800
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Thomas Gleixner <tglx@linutronix.de>, peterz@infradead.org,
        jstultz@google.com, edumazet@google.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/3] softirq: avoid spurious stalls due to need_resched()
Message-ID: <20230304031109.GG1301832@paulmck-ThinkPad-P17-Gen-1>
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On Fri, Mar 03, 2023 at 05:39:21PM -0800, Jakub Kicinski wrote:
> On Fri, 3 Mar 2023 17:25:35 -0800 Paul E. McKenney wrote:
> > > Just to be sure - have you seen Peter's patches?
> > > 
> > >   git://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git core/softirq
> > > 
> > > I think it feeds the time limit to the callback from softirq,
> > > so the local 3ms is no more?  
> > 
> > I might or might not have back in September of 2020.  ;-)
> > 
> > But either way, the question remains:  Should RCU_SOFTIRQ do time checking
> > in ksoftirqd context?  Seems like the answer should be "yes", independently
> > of Peter's patches.
> 
> :-o  I didn't notice, I thought that's from Dec 22, LWN was writing
> about Peter's rework at that point. I'm not sure what the story is :(
> And when / if any of these changes are coming downstream.

Not a problem either way, as the compiler would complain bitterly about
the resulting merge conflict and it is easy to fix.  ;-)

							Thanx, Paul