> -----Original Message-----
> From: Ananyev, Konstantin
> Sent: Tuesday, October 27, 2015 12:13 PM
> To: Richardson, Bruce; Traynor, Kevin
> Cc: dev at dpdk.org
> Subject: RE: [dpdk-dev] [PATCH] ixgbe: change logging for ixgbe tx code path
> selection
>
>
>
> > -----Original Message-----
> > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Bruce Richardson
> > Sent: Tuesday, October 27, 2015 11:50 AM
> > To: Traynor, Kevin
> > Cc: dev at dpdk.org
> > Subject: Re: [dpdk-dev] [PATCH] ixgbe: change logging for ixgbe tx code
> path selection
> >
> > On Tue, Oct 27, 2015 at 11:41:08AM +0000, Kevin Traynor wrote:
> > > Simple and vector are different tx code paths. If vector
> > > is selected, change logging from:
> > > PMD: ixgbe_set_tx_function(): Using simple tx code path
> > > PMD: ixgbe_set_tx_function(): Vector tx enabled.
> > >
> > > to:
> > > PMD: ixgbe_set_tx_function(): Using vector tx code path
> > >
> > > or, if simple selected:
> > > PMD: ixgbe_set_tx_function(): Using simple tx code path
> > >
> > > The dangling else in the #ifdef makes readability difficult,
> > > so resolving in way that seems most readable.
> > >
> > > Signed-off-by: Kevin Traynor <kevin.traynor at intel.com>
> > > ---
> > > drivers/net/ixgbe/ixgbe_rxtx.c | 8 +++++---
> > > 1 files changed, 5 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/drivers/net/ixgbe/ixgbe_rxtx.c
> b/drivers/net/ixgbe/ixgbe_rxtx.c
> > > index a598a72..11d7feb 100644
> > > --- a/drivers/net/ixgbe/ixgbe_rxtx.c
> > > +++ b/drivers/net/ixgbe/ixgbe_rxtx.c
> > > @@ -1963,16 +1963,18 @@ ixgbe_set_tx_function(struct rte_eth_dev *dev,
> struct ixgbe_tx_queue *txq)
> > > /* Use a simple Tx queue (no offloads, no multi segs) if possible */
> > > if (((txq->txq_flags & IXGBE_SIMPLE_FLAGS) == IXGBE_SIMPLE_FLAGS)
> > > && (txq->tx_rs_thresh >= RTE_PMD_IXGBE_TX_MAX_BURST)) {
> > > - PMD_INIT_LOG(DEBUG, "Using simple tx code path");
> > > #ifdef RTE_IXGBE_INC_VECTOR
> > > if (txq->tx_rs_thresh <= RTE_IXGBE_TX_MAX_FREE_BUF_SZ &&
> > > (rte_eal_process_type() != RTE_PROC_PRIMARY ||
> > > ixgbe_txq_vec_setup(txq) == 0)) {
> > > - PMD_INIT_LOG(DEBUG, "Vector tx enabled.");
> > > + PMD_INIT_LOG(DEBUG, "Using vector tx code path");
> > > dev->tx_pkt_burst = ixgbe_xmit_pkts_vec;
> > > } else
> > > #endif
> > > - dev->tx_pkt_burst = ixgbe_xmit_pkts_simple;
> > > + {
> > > + PMD_INIT_LOG(DEBUG, "Using simple tx code path");
> > > + dev->tx_pkt_burst = ixgbe_xmit_pkts_simple;
> > > + }
> > > } else {
> > > PMD_INIT_LOG(DEBUG, "Using full-featured tx code path");
> > > PMD_INIT_LOG(DEBUG,
> > > --
> > > 1.7.4.1
> > >
> > Hi Kevin,
> >
> > can I suggest a slight alternative here that might help make things easier.
> > Instead of printing the message as we pick the code path, why not have a
> "logmsg"
> > pointer variable that is assigned in the code, and then print out the log
> path
> > at the end.
> >
> > This would have a number of advantages:
> > 1. there are no issues with changing our mind, so we can assign one path
> type,
> > and then later change it to something different without cluttering up the
> debug
> > output with the history of our code's flow.
> > 2. it means that you don't have a problem with smaller else legs as you can
> > easily do multiple assignments in the one line using a comma as:
> > dev->tx_pkt_burst = ixgbe_xmit_pkts_simple, logmsg = "Using simple
> ...";
>
> While I like approach with logmsg, please avoid commas here.
> It will make this peace of code even more hard to read (at least for me).
> Konstantin
yeah, sure. I agree with changing for 1. I also agree with Konstantin re commas.
The code under the dangling else is aligned incorrectly/correctly depending on
whether the #ifdef is true or not, so I think adding multiple statements with {}
now will make it obvious for the next person who modifies.
>
> >
> > Regards,
> > /Bruce
