On 2/12/19 3:16 PM, Eric Blake wrote:
> On 2/12/19 2:07 PM, John Snow wrote:
>> When bitmaps are persistent, they may incur a disk read or write when bitmaps
>> are added or removed. For configurations like virtio-dataplane, failing to
>> acquire this lock will abort QEMU when disk IO occurs.
>>
>> We used to acquire aio_context as part of the bitmap lookup, so re-introduce
>> the lock for just the cases that have an IO penalty.
>
> It would be nice to call out which commit id dropped the aio_context
> acquisition during bitmap lookup (making it easier to analyze how long
> this has broken, and which downstream builds need the backport.
>
OK, I will amend this.
Looks like:
commit 2119882c7eb7e2c612b24fc0c8d86f5887d6f1c3
Author: Paolo Bonzini <pbonz...@redhat.com>
Date: Mon Jun 5 14:39:03 2017 +0200
since 2.10.
>>
>> Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1672010
>> Reported-By: Aihua Liang <ali...@redhat.com>
>> ---
>> blockdev.c | 26 ++++++++++++++++++++------
>> 1 file changed, 20 insertions(+), 6 deletions(-)
>
> Reviewed-by: Eric Blake <ebl...@redhat.com>
>
