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Subject: Re: [PATCH v2] kvm: Replace vcpu->swait with rcuwait
To:     Davidlohr Bueso <dave@stgolabs.net>, Marc Zyngier <maz@kernel.org>
Cc:     tglx@linutronix.de, kvm@vger.kernel.org,
        Davidlohr Bueso <dbueso@suse.de>, peterz@infradead.org,
        torvalds@linux-foundation.org, bigeasy@linutronix.de,
        linux-kernel@vger.kernel.org, rostedt@goodmis.org,
        linux-mips@vger.kernel.org, Paul Mackerras <paulus@ozlabs.org>,
        joel@joelfernandes.org, will@kernel.org,
        kvmarm@lists.cs.columbia.edu
References: <20200324044453.15733-1-dave@stgolabs.net>
 <20200324044453.15733-4-dave@stgolabs.net>
 <20200420164132.tjzk5ebx35m66yce@linux-p48b>
 <418acdb5001a9ae836095b7187338085@misterjones.org>
 <20200420205641.6sgsllj6pmsnwrvp@linux-p48b>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <f7cc83fe-3e91-0057-9af2-26c201456689@redhat.com>
Date:   Mon, 20 Apr 2020 23:04:37 +0200
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On 20/04/20 22:56, Davidlohr Bueso wrote:
> On Mon, 20 Apr 2020, Marc Zyngier wrote:
> 
>> This looks like a change in the semantics of the tracepoint. Before this
>> change, 'waited' would have been true if the vcpu waited at all. Here,
>> you'd
>> have false if it has been interrupted by a signal, even if the vcpu
>> has waited
>> for a period of time.
> 
> Hmm but sleeps are now uninterruptible as we're using TASK_IDLE.

Hold on, does that mean that you can't anymore send a signal in order to
kick a thread out of KVM_RUN?  Or am I just misunderstanding?

Paolo