Re: [PATCH] sched/rt: Do not pull from current CPU if only one cpu to pull

2017-12-11 Thread Steven Rostedt
On Mon, 11 Dec 2017 17:47:32 +0100 Ingo Molnar wrote: > > Link: > > http://lkml.kernel.org/r/8c913cc2-b2e3-8c2e-e503-aff1428f8...@monom.org > > Fixes: 4bdced5c9 ("sched/rt: Simplify the IPI based RT balancing logic") > > Cc: sta...@vger.kernel.org > > Reported-by: Daniel Wagner > > I've adde

Re: [PATCH] sched/rt: Do not pull from current CPU if only one cpu to pull

2017-12-11 Thread Ingo Molnar
* Steven Rostedt wrote: > Daniel Wagner reported a crash on the beaglebone black. This is a > single CPU architecture, and does not have a functional: > arch_send_call_function_single_ipi() and can crash if that is called. > > As it only has one CPU, it shouldn't be called, but if the kernel is

Re: [PATCH] sched/rt: Do not pull from current CPU if only one cpu to pull

2017-12-04 Thread Daniel Wagner
Hi Steven, On 12/02/2017 07:04 PM, Steven Rostedt wrote: > Daniel Wagner reported a crash on the beaglebone black. This is a > single CPU architecture, and does not have a functional: > arch_send_call_function_single_ipi() and can crash if that is called. > > As it only has one CPU, it shouldn't

Re: [PATCH] sched/rt: Do not pull from current CPU if only one cpu to pull

2017-12-04 Thread Steven Rostedt
On Mon, 4 Dec 2017 10:07:57 +0100 Juri Lelli wrote: > On 04/12/17 03:09, Steven Rostedt wrote: > > On Mon, 4 Dec 2017 08:45:17 +0100 > > Juri Lelli wrote: > > > > > Right. I was wondering however if for the truly UP case we shouldn't be > > > initiating/queueing callbacks (pull/push) at all?

Re: [PATCH] sched/rt: Do not pull from current CPU if only one cpu to pull

2017-12-04 Thread Juri Lelli
On 04/12/17 03:09, Steven Rostedt wrote: > On Mon, 4 Dec 2017 08:45:17 +0100 > Juri Lelli wrote: > > > Right. I was wondering however if for the truly UP case we shouldn't be > > initiating/queueing callbacks (pull/push) at all? > > If !CONFIG_SMP then it's not compiled in. The issue came up whe

Re: [PATCH] sched/rt: Do not pull from current CPU if only one cpu to pull

2017-12-04 Thread Steven Rostedt
On Mon, 4 Dec 2017 08:45:17 +0100 Juri Lelli wrote: > Right. I was wondering however if for the truly UP case we shouldn't be > initiating/queueing callbacks (pull/push) at all? If !CONFIG_SMP then it's not compiled in. The issue came up when Daniel ran a CONFIG_SMP kernel on an arch that only s

Re: [PATCH] sched/rt: Do not pull from current CPU if only one cpu to pull

2017-12-03 Thread Juri Lelli
Hi Steve, On 02/12/17 13:04, Steven Rostedt wrote: > Daniel Wagner reported a crash on the beaglebone black. This is a > single CPU architecture, and does not have a functional: > arch_send_call_function_single_ipi() and can crash if that is called. > > As it only has one CPU, it shouldn't be cal