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From: valdis.kletnieks@vt.edu
To: Ivid Suvarna <ivid.suvarna@gmail.com>
Cc: Kernel development list <linux-kernel@vger.kernel.org>,
	kernelnewbies@kernelnewbies.org
Subject: Re: Softlockup and Hardlockup sample test module
Date: Sun, 15 Apr 2018 15:12:11 -0400	[thread overview]
Message-ID: <90446.1523819531@turing-police.cc.vt.edu> (raw)
In-Reply-To: <CABXF_ACzu=+AKYqPyZwFzFw95KrczVEKaYifmOVuv=YhsvcTtQ@mail.gmail.com>

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On Sun, 15 Apr 2018 13:17:27 +0530, Ivid Suvarna said:

> I had tried with the module where I put a busy loop inside spinlock
> but was not able to cause any lockups. Maybe this is because of SMP
> which schedule the job to other CPU. "How do I make a task to run on
> single CPU only?"

So you get a kernel thread that's taken a lock and will busy-loop and not free
it.  What sort of lockup do you expect will be detected from this? Would the
results be any different if you didn't take a lock before busy-looping?

For bonus points - what additional things have to happen before a livelock
happens?

And before a deadlock happens?

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  reply	other threads:[~2018-04-15 19:12 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-15  7:47 Ivid Suvarna
2018-04-15 19:12 ` valdis.kletnieks [this message]
2018-04-15 22:19 ` Cong Wang
  -- strict thread matches above, loose matches on Subject: below --
2018-04-15  5:41 Ivid Suvarna

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