Date: Sat, 29 Oct 2016 09:52:16 -0700
From: Davidlohr Bueso <dave@stgolabs.net>
To: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        virtualization@lists.linux-foundation.org, linux-s390@vger.kernel.org,
        xen-devel-request@lists.xenproject.org, kvm@vger.kernel.org,
        xen-devel@lists.xenproject.org, x86@kernel.org,
        benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au,
        mingo@redhat.com, peterz@infradead.org, paulmck@linux.vnet.ibm.com,
        will.deacon@arm.com, kernellwp@gmail.com, jgross@suse.com,
        pbonzini@redhat.com, bsingharora@gmail.com, boqun.feng@gmail.com,
        borntraeger@de.ibm.com, rkrcmar@redhat.com, David.Laight@ACULAB.COM
Subject: Re: [PATCH v6 02/11] locking/osq: Drop the overload of osq_lock()
Message-ID: <20161029165216.GA17451@linux-80c1.suse>
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On Fri, 28 Oct 2016, Pan Xinhui wrote:
> 		/*
> 		 * If we need to reschedule bail... so we can block.
>+		 * Use vcpu_is_preempted to detech lock holder preemption issue
                                            ^^ detect
>+		 * and break. 

Could you please remove the rest of this comment? Its just noise to point out
that vcpu_is_preempted is a macro defined by arch/false. This is standard protocol
in the kernel.

Same goes for all locks you change with this.

Thanks,
Davidlohr

>                * vcpu_is_preempted is a macro defined by false if
>+		 * arch does not support vcpu preempted check,
> 		 */
>-		if (need_resched())
>+		if (need_resched() || vcpu_is_preempted(node_cpu(node->prev)))
> 			goto unqueue;
>
> 		cpu_relax_lowlatency();
>-- 
>2.4.11
>