Re: [PATCH v2 1/4] net: ethernet: ti: davinci_cpdma: split descs num between all channels

[Ivan Khoronzhuk]

On 15.08.16 19:05, Yuval Mintz wrote:
> > Currently the tx channels share same pool of descriptors. Thus one channel can
> > block another if pool is emptied by one. But, the shaper should decide which
> > channel is allowed to send packets. To avoid such impact of one channel on
> > another, let every channel to have its own peace of pool.
> Piece.
Yep.

> > +/**
> > + * cpdma_chan_split_pool - Splits ctrl pool between all channels.
> > + * Has to be called under ctlr lock
> > + *
> > + */
> No need for the extra empty comment line.
Ok.

> > +	/* calculate average size of pool slice */
> > +	ch_desc_num = pool->num_desc / ctlr->chan_num;
> > +
> > +	/* split ctlr pool */
> > +	for (i = 0; i < ARRAY_SIZE(ctlr->channels); i++) {
> > +		chan = ctlr->channels[i];
> > +		if (chan)
> > +			chan->desc_num = ch_desc_num;
> Is this 'if' needed? If there's some route where the channel can be NULL,
> You're splitting the value incorrectly.
If chan == NULL it's not active and pool->chan_num doesn't include it.
The descriptors are split between active channels only.

>

--
Regards,
Ivan Khoronzhuk