Re: [Qemu-devel] [PATCH 44/47] mirror: switch mirror_iteration to AIO

[Paolo Bonzini]

Il 28/07/2012 15:46, Eric Blake ha scritto:
> On 07/24/2012 05:04 AM, Paolo Bonzini wrote:
>> There is really no change in the behavior of the job here, since there
>> is still a maximum of one in-flight I/O operation between the source and
>> the target.  However, this patch already introduces moves the copy logic
> 
> grammar: 'already introduces moves' is awkward, but I'm not sure what
> you meant.
> 
>> from mirror_iteration to AIO callbacks; it also adds the logic to count
>> in-flight operations, and only complete the job after they have finished.
> 
> s/complete/completes/

Wow, I'm embarrassed...

>>
>> Some care is required in the error and cancellation cases, in order
>> to avoid access to dangling pointers (and consequent corruption).
>>
>> Signed-off-by: Paolo Bonzini <address@hidden>
>> ---
>>  block/mirror.c |  161 
>> ++++++++++++++++++++++++++++++++++++++++++--------------
>>  trace-events   |    2 +
>>  2 files changed, 123 insertions(+), 40 deletions(-)
>>
>> diff --git a/block/mirror.c b/block/mirror.c
>> index 81a600b..971c923 100644
>> --- a/block/mirror.c
>> +++ b/block/mirror.c
>> @@ -17,7 +17,7 @@
>>  #include "qemu/ratelimit.h"
>>  #include "bitmap.h"
>>  
>> -#define SLICE_TIME 100000000ULL /* ns */
>> +#define SLICE_TIME    100000000ULL /* ns */
> 
> Why the spurious respacing?

This patch was split from the one that introduces MAX_IN_FLIGHT.

 #define SLICE_TIME    100000000ULL /* ns */
+#define MAX_IN_FLIGHT 16

so the respacing belongs there.

Paolo