[PATCH 5.11 537/775] ice: update the number of available RSS queues

From: Greg Kroah-Hartman
Date: Tue Mar 02 2021 - 00:54:59 EST


From: Henry Tieman <henry.w.tieman@xxxxxxxxx>

[ Upstream commit 0393e46ac48a6832b1011c233ebcef84f8dbe4f5 ]

It was possible to have Rx queues that were not available for use
by RSS. This would happen when increasing the number of Rx queues
while there was a user defined RSS LUT.

Always update the number of available RSS queues when changing the
number of Rx queues.

Fixes: 87324e747fde ("ice: Implement ethtool ops for channels")
Signed-off-by: Henry Tieman <henry.w.tieman@xxxxxxxxx>
Tested-by: Tony Brelinski <tonyx.brelinski@xxxxxxxxx>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/intel/ice/ice_ethtool.c | 27 ++++++++++++++------
1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index d27b9cb3e8082..aebebd2102da0 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -3328,6 +3328,18 @@ ice_get_channels(struct net_device *dev, struct ethtool_channels *ch)
ch->max_other = ch->other_count;
}

+/**
+ * ice_get_valid_rss_size - return valid number of RSS queues
+ * @hw: pointer to the HW structure
+ * @new_size: requested RSS queues
+ */
+static int ice_get_valid_rss_size(struct ice_hw *hw, int new_size)
+{
+ struct ice_hw_common_caps *caps = &hw->func_caps.common_cap;
+
+ return min_t(int, new_size, BIT(caps->rss_table_entry_width));
+}
+
/**
* ice_vsi_set_dflt_rss_lut - set default RSS LUT with requested RSS size
* @vsi: VSI to reconfigure RSS LUT on
@@ -3355,14 +3367,10 @@ static int ice_vsi_set_dflt_rss_lut(struct ice_vsi *vsi, int req_rss_size)
return -ENOMEM;

/* set RSS LUT parameters */
- if (!test_bit(ICE_FLAG_RSS_ENA, pf->flags)) {
+ if (!test_bit(ICE_FLAG_RSS_ENA, pf->flags))
vsi->rss_size = 1;
- } else {
- struct ice_hw_common_caps *caps = &hw->func_caps.common_cap;
-
- vsi->rss_size = min_t(int, req_rss_size,
- BIT(caps->rss_table_entry_width));
- }
+ else
+ vsi->rss_size = ice_get_valid_rss_size(hw, req_rss_size);

/* create/set RSS LUT */
ice_fill_rss_lut(lut, vsi->rss_table_size, vsi->rss_size);
@@ -3441,9 +3449,12 @@ static int ice_set_channels(struct net_device *dev, struct ethtool_channels *ch)

ice_vsi_recfg_qs(vsi, new_rx, new_tx);

- if (new_rx && !netif_is_rxfh_configured(dev))
+ if (!netif_is_rxfh_configured(dev))
return ice_vsi_set_dflt_rss_lut(vsi, new_rx);

+ /* Update rss_size due to change in Rx queues */
+ vsi->rss_size = ice_get_valid_rss_size(&pf->hw, new_rx);
+
return 0;
}

--
2.27.0