Message-Id: <56F0087202000078000DED9F@prv-mh.provo.novell.com>
Date: Mon, 21 Mar 2016 07:42:58 -0600
From: "Jan Beulich" <JBeulich@suse.com>
To: "Juergen Gross" <JGross@suse.com>
Cc: <david.vrabel@citrix.com>, <Douglas_Warzecha@dell.com>,
        <pali.rohar@gmail.com>, <jeremy@goop.org>, <peterz@infradead.org>,
        <x86@kernel.org>, <tglx@linutronix.de>,
        <virtualization@lists.linux-foundation.org>,
        <xen-devel@lists.xenproject.org>, <boris.ostrovsky@oracle.com>,
        <mingo@redhat.com>, <linux@roeck-us.net>, <rusty@rustcorp.com.au>,
        <chrisw@sous-sol.org>, "Jean Delvare" <jdelvare@suse.com>,
        <linux-kernel@vger.kernel.org>, <akataria@vmware.com>, <hpa@zytor.com>
Subject: Re: [Xen-devel] [PATCH v2 5/6] virt, sched: add cpu pinning to
 smp_call_sync_on_phys_cpu()
References: <1458563075-30298-1-git-send-email-jgross@suse.com>
 <1458563075-30298-6-git-send-email-jgross@suse.com>
In-Reply-To: <1458563075-30298-6-git-send-email-jgross@suse.com>
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>>> On 21.03.16 at 13:24, <JGross@suse.com> wrote:
> @@ -758,9 +759,14 @@ struct smp_sync_call_struct {
>  static void smp_call_sync_callback(struct work_struct *work)
>  {
>  	struct smp_sync_call_struct *sscs;
> +	unsigned int cpu = smp_processor_id();

So this obtains the vCPU number, yet ...

>  	sscs = container_of(work, struct smp_sync_call_struct, work);
> +	preempt_disable();
> +	hypervisor_pin_vcpu(cpu);

... here you're supposed to pass a pCPU number.

Also don't you need to call smp_processor_id() after preempt_disable()?

Jan