On 04/09/2013 02:53 PM, Paolo Bonzini wrote:
> Il 09/04/2013 13:43, Juan Quintela ha scritto:
>>>> @@ -687,12 +685,10 @@ void qemu_put_byte(QEMUFile *f, int v)
>>>> f->bytes_xfer++;
>>>> if (f->ops->writev_buffer) {
>>>> add_to_iovec(f, f->buf + f->buf_index, 1);
>>>> - f->buf_index++;
>>>> - } else {
>>>> - f->buf_index++;
>>>> - if (f->buf_index == IO_BUF_SIZE) {
>>>> - qemu_fflush(f);
>>>> - }
>>>> + }
>>>> + f->buf_index++;
>>>> + if (f->buf_index == IO_BUF_SIZE) {
>>>> + qemu_fflush(f);
>>>> }
>>>> }
>> If you follow my advice of moving the call to add_to_iovec() you get
>> this one simplified and only one place to do this.
>
> Moving what call? The apparent complication is because the old logic
> was a bit more involute than necessary. If you look at the code after
> the patches, not the patches themselves, you'll see for yourself.
>
> The logic now is:
>
> add byte
> if using iovs
> add byte to iov list
> if buffer full
> flush
>
> add_to_iovec has no business checking the buffer. Why should
> qemu_put_buffer_async() check the buffer?
>
> The duplication between qemu_put_byte and qemu_put_buffer is a different
> topic. I think it's acceptable in the name of performance, but perhaps
> you can just call qemu_put_buffer(f, &c, 1).
I thought about it too, we can keep the optimization by checking the size
Orit
>
> Paolo
>
