bitmap_weight() is O(N) and useless here, because the following for_each_set_bit() returns immediately in case of empty flow_pctypes.
Signed-off-by: Yury Norov (NVIDIA) <[email protected]> --- v1: https://lore.kernel.org/all/[email protected]/ v2: don't drop flow_id (Aleksandr). .../net/ethernet/intel/i40e/i40e_ethtool.c | 21 +++++++------------ 1 file changed, 8 insertions(+), 13 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c index f2c2646ea298..e64880b6b047 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c +++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c @@ -3637,6 +3637,7 @@ static int i40e_set_rxfh_fields(struct net_device *netdev, ((u64)i40e_read_rx_ctl(hw, I40E_PFQF_HENA(1)) << 32); DECLARE_BITMAP(flow_pctypes, FLOW_PCTYPES_SIZE); u64 i_set, i_setc; + u8 flow_id; bitmap_zero(flow_pctypes, FLOW_PCTYPES_SIZE); @@ -3720,20 +3721,14 @@ static int i40e_set_rxfh_fields(struct net_device *netdev, return -EINVAL; } - if (bitmap_weight(flow_pctypes, FLOW_PCTYPES_SIZE)) { - u8 flow_id; + for_each_set_bit(flow_id, flow_pctypes, FLOW_PCTYPES_SIZE) { + i_setc = (u64)i40e_read_rx_ctl(hw, I40E_GLQF_HASH_INSET(0, flow_id)) | + ((u64)i40e_read_rx_ctl(hw, I40E_GLQF_HASH_INSET(1, flow_id)) << 32); + i_set = i40e_get_rss_hash_bits(&pf->hw, nfc, i_setc); - for_each_set_bit(flow_id, flow_pctypes, FLOW_PCTYPES_SIZE) { - i_setc = (u64)i40e_read_rx_ctl(hw, I40E_GLQF_HASH_INSET(0, flow_id)) | - ((u64)i40e_read_rx_ctl(hw, I40E_GLQF_HASH_INSET(1, flow_id)) << 32); - i_set = i40e_get_rss_hash_bits(&pf->hw, nfc, i_setc); - - i40e_write_rx_ctl(hw, I40E_GLQF_HASH_INSET(0, flow_id), - (u32)i_set); - i40e_write_rx_ctl(hw, I40E_GLQF_HASH_INSET(1, flow_id), - (u32)(i_set >> 32)); - hena |= BIT_ULL(flow_id); - } + i40e_write_rx_ctl(hw, I40E_GLQF_HASH_INSET(0, flow_id), (u32)i_set); + i40e_write_rx_ctl(hw, I40E_GLQF_HASH_INSET(1, flow_id), (u32)(i_set >> 32)); + hena |= BIT_ULL(flow_id); } i40e_write_rx_ctl(hw, I40E_PFQF_HENA(0), (u32)hena); -- 2.43.0
