Re: [dpdk-stable] [PATCH 19.11.6] ethdev: fix data type in TC queues

[Luca Boccassi <bluca@debian.org>]

On Wed, 2020-11-04 at 18:35 +0800, oulijun wrote:
> 
> 在 2020/11/3 17:21, Luca Boccassi 写道:
> > On Tue, 2020-11-03 at 17:04 +0800, Lijun Ou wrote:
> > > From: Huisong Li <lihuisong@huawei.com>
> > > 
> > > [ upstream commit 9f6dc8592d54aa2ec1800c53977a31bd7922147b ]
> > > 
> > > Currently, base and nb_queue in the tc_rxq and tc_txq information
> > > of queue and TC mapping on both TX and RX paths are uint8_t.
> > > However, these data will be truncated when queue number under a TC
> > > is greater than 256. So it is necessary for base and nb_queue to
> > > change from uint8_t to uint16_t.
> > > 
> > > Fixes: 89d6728c7837 ("ethdev: get DCB information")
> > > Cc: stable@dpdk.org
> > > 
> > > Signed-off-by: Huisong Li <lihuisong@huawei.com>
> > > Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
> > > Reviewed-by: Wei Hu (Xavier) <xavier.huwei@huawei.com>
> > > Reviewed-by: Dongdong Liu <liudongdong3@huawei.com>
> > > Acked-by: Thomas Monjalon <thomas@monjalon.net>
> > > Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
> > > ---
> > >   doc/guides/rel_notes/release_19_11.rst | 5 +++++
> > >   lib/librte_ethdev/rte_ethdev.h         | 8 ++++----
> > >   2 files changed, 9 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/doc/guides/rel_notes/release_19_11.rst b/doc/guides/rel_notes/release_19_11.rst
> > > index acd18a3..cba8ebd 100644
> > > --- a/doc/guides/rel_notes/release_19_11.rst
> > > +++ b/doc/guides/rel_notes/release_19_11.rst
> > > @@ -457,6 +457,11 @@ API Changes
> > >   * ethdev: changed ``rte_eth_dev_owner_delete`` return value from ``void`` to
> > >     ``int`` to provide a way to report various error conditions.
> > >   
> > > +* ethdev: Modified field type of ``base`` and ``nb_queue`` in struct
> > > +  ``rte_eth_dcb_tc_queue_mapping`` from ``uint8_t`` to ``uint16_t``.
> > > +  As the data of ``uint8_t`` will be truncated when queue number under
> > > +  a TC is greater than 256.
> > > +
> > >   * ethdev: The deprecated function ``rte_eth_dev_count`` was removed.
> > >     The function ``rte_eth_dev_count_avail`` is a drop-in replacement.
> > >     If the intent is to iterate over ports, ``RTE_ETH_FOREACH_*`` macros
> > > diff --git a/lib/librte_ethdev/rte_ethdev.h b/lib/librte_ethdev/rte_ethdev.h
> > > index 51f9f25..5fedff0 100644
> > > --- a/lib/librte_ethdev/rte_ethdev.h
> > > +++ b/lib/librte_ethdev/rte_ethdev.h
> > > @@ -1360,13 +1360,13 @@ struct rte_eth_xstat_name {
> > >   struct rte_eth_dcb_tc_queue_mapping {
> > >   	/** rx queues assigned to tc per Pool */
> > >   	struct {
> > > -		uint8_t base;
> > > -		uint8_t nb_queue;
> > > +		uint16_t base;
> > > +		uint16_t nb_queue;
> > >   	} tc_rxq[ETH_MAX_VMDQ_POOL][ETH_DCB_NUM_TCS];
> > >   	/** rx queues assigned to tc per Pool */
> > >   	struct {
> > > -		uint8_t base;
> > > -		uint8_t nb_queue;
> > > +		uint16_t base;
> > > +		uint16_t nb_queue;
> > >   	} tc_txq[ETH_MAX_VMDQ_POOL][ETH_DCB_NUM_TCS];
> > >   };
> > 
> > Hi,
> > 
> > Thanks for the patch, but isn't this an ABI breakage? This is a public
> > header right?
> > 
> I understand that an ABI breakage has been announced.

Sure, that's fine for mainline 20.11 - but we never break ABI in LTS
releases. Hence I will skip this patch for 19.11.6.

-- 
Kind regards,
Luca Boccassi