From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: [PATCH 2/4] VMX: Turn on posted interrupt bit in
	vmcs
Date: Tue, 09 Apr 2013 09:38:08 +0100
Message-ID: <CD899200.2058F%keir.xen@gmail.com>
References: <5163EC0702000078000CBA0E@nat28.tlf.novell.com>
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To: Jan Beulich <JBeulich@suse.com>, Yang Zhang <yang.z.zhang@intel.com>
Cc: xiantao.zhang@intel.com, xen-devel@lists.xen.org
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On 09/04/2013 09:23, "Jan Beulich" <JBeulich@suse.com> wrote:

>>>> On 09.04.13 at 08:01, Yang Zhang <yang.z.zhang@intel.com> wrote:
>> +static void posted_interrupt_handler(struct cpu_user_regs *regs)
>> +{
>> +    ack_APIC_irq();
>> +    perfc_incr(ipis);
>> +    this_cpu(irq_count)++;
>> +}
> 
> If I'm not mistaken, there's no further code being added to this
> interrupt handler in the subsequent patches. What's the point
> for the separate interrupt then? I.e. is there any reason not to
> reuse event_check_interrupt() and EVENT_CHECK_VECTOR?

The new POSTED_INTERRUPT_VECTOR has special behaviour when delivered in vmx
non-root mode, so it has to be distinct from the EVENT_CHECK_VECTOR. Still,
it could share event_check_interrupt() -- there is no need at all for
posted_interrupt_handler() to exist.

 -- Keir

> Jan
>