| Message ID | 20211213153111.110877-5-maciej.fijalkowski@intel.com (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | ice: xsk: Rx processing fixes | expand |
> -----Original Message----- > From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of > Maciej Fijalkowski > Sent: Monday, December 13, 2021 9:01 PM > To: intel-wired-lan@lists.osuosl.org > Cc: Mathew, Elza <elza.mathew@intel.com>; netdev@vger.kernel.org; > kuba@kernel.org; bpf@vger.kernel.org; davem@davemloft.net; Karlsson, > Magnus <magnus.karlsson@intel.com> > Subject: [Intel-wired-lan] [PATCH v2 intel-net 4/6] ice: xsk: do not clear > status_error0 for ntu + nb_buffs descriptor > > The descriptor that ntu is pointing at when we exit > ice_alloc_rx_bufs_zc() should not have its corresponding DD bit cleared as > descriptor is not allocated in there and it is not valid for HW usage. > > The allocation routine at the entry will fill the descriptor that ntu points to > after it was set to ntu + nb_buffs on previous call. > > Even the spec says: > "The tail pointer should be set to one descriptor beyond the last empty > descriptor in host descriptor ring." > > Therefore, step away from clearing the status_error0 on ntu + nb_buffs > descriptor. > > Fixes: db804cfc21e9 ("ice: Use the xsk batched rx allocation interface") > Reported-by: Elza Mathew <elza.mathew@intel.com> > Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> > --- > drivers/net/ethernet/intel/ice/ice_xsk.c | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) > Tested-by: Kiran Bhandare <kiranx.bhandare@intel.com> A Contingent Worker at Intel
diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c b/drivers/net/ethernet/intel/ice/ice_xsk.c index 27f5f64dcbd6..ffa9a160766a 100644 --- a/drivers/net/ethernet/intel/ice/ice_xsk.c +++ b/drivers/net/ethernet/intel/ice/ice_xsk.c @@ -395,13 +395,9 @@ bool ice_alloc_rx_bufs_zc(struct ice_rx_ring *rx_ring, u16 count) } ntu += nb_buffs; - if (ntu == rx_ring->count) { - rx_desc = ICE_RX_DESC(rx_ring, 0); + if (ntu == rx_ring->count) ntu = 0; - } - /* clear the status bits for the next_to_use descriptor */ - rx_desc->wb.status_error0 = 0; ice_release_rx_desc(rx_ring, ntu); return count == nb_buffs;
The descriptor that ntu is pointing at when we exit ice_alloc_rx_bufs_zc() should not have its corresponding DD bit cleared as descriptor is not allocated in there and it is not valid for HW usage. The allocation routine at the entry will fill the descriptor that ntu points to after it was set to ntu + nb_buffs on previous call. Even the spec says: "The tail pointer should be set to one descriptor beyond the last empty descriptor in host descriptor ring." Therefore, step away from clearing the status_error0 on ntu + nb_buffs descriptor. Fixes: db804cfc21e9 ("ice: Use the xsk batched rx allocation interface") Reported-by: Elza Mathew <elza.mathew@intel.com> Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> --- drivers/net/ethernet/intel/ice/ice_xsk.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)