Re: [Qemu-devel] [PATCH v3 08/10] Use QemuEvent for POSIX AIO

[Jan Kiszka]

On 2012-04-10 17:31, Stefan Hajnoczi wrote:
> On Thu, Apr 5, 2012 at 11:59 AM, Jan Kiszka <address@hidden> wrote:
>> Use QemuEvent for signaling POSIX AIO completions. If native eventfd
>> support is available, this avoids multiple read accesses to drain
>> multiple pending signals.
>>
>> Signed-off-by: Jan Kiszka <address@hidden>
>> ---
>>  posix-aio-compat.c |   62 
>> ++++++----------------------------------------------
>>  1 files changed, 7 insertions(+), 55 deletions(-)
> 
> We can save a file descriptor by scheduling a BH (if not already
> scheduled) and calling qemu_notify_event() instead of using a
> dedicated QemuEvent.  I may have missed something, just got back from
> vacation :).

Likely feasible, but not that straightforward: We would still have to
provide qemu_aio_{wait,flush,...} services for posix-aio-compat, I presume.

Jan

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