Paolo Bonzini <pbonz...@redhat.com> 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?
We can rename the function. I agree with that.
>
> 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).
Right now, it is important because all the integer types are sent as
callas to qemu_put_byte(), but Orit had a patch to rewrote those using
qemu_put_buffer() dirrectly, and then we don't use so many
qemu_put_byte()'s anymore.
Later, Juan.
