From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: [PATCHv1 2/2] passthrough: improve locking when
 iterating over interrupts bound to VMs
Date: Tue, 27 Oct 2015 13:11:05 +0000
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To: Jan Beulich <JBeulich@suse.com>, David Vrabel <david.vrabel@citrix.com>
Cc: xen-devel@lists.xenproject.org, Ian Campbell <ian.campbell@citrix.com>
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On 27/10/15 12:44, Jan Beulich wrote:
>>>> On 23.10.15 at 13:05, <david.vrabel@citrix.com> wrote:
>> radix_tree_gang_lookup() only requires a RCU read lock, not the
>> per-domain event_lock.
> 
> ... when not caring about a consistent snapshot.
> 
>> @@ -678,9 +684,7 @@ void hvm_dpci_msi_eoi(struct domain *d, int vector)
>>      if ( !iommu_enabled || !d->arch.hvm_domain.irq.dpci )
>>         return;
>>  
>> -    spin_lock(&d->event_lock);
>>      pt_pirq_iterate(d, _hvm_dpci_msi_eoi, (void *)(long)vector);
>> -    spin_unlock(&d->event_lock);
>>  }
> 
> How about other callers of pt_pirq_iterate()?

They weren't hot so I didn't look at them.

David