iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

i40e, xsk: remove HW descriptor prefetch in AF_XDP path

Browse Source 
The software prefetching of HW descriptors has a negative impact on
the performance. Therefore, it is now removed.

Performance for the rx_drop benchmark increased with 2%.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
This commit is contained in:
Björn Töpel 2020-08-25 13:35:54 +02:00 committed by Tony Nguyen
parent 1fa5cef283
commit f78bd13027
3 changed files with 25 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/net/ethernet/intel/i40e/i40e_txrx.c
View File

@ -2295,6 +2295,19 @@ void i40e_finalize_xdp_rx(struct i40e_ring *rx_ring, unsigned int xdp_res)
}
}
/**
* i40e_inc_ntc: Advance the next_to_clean index
* @rx_ring: Rx ring
**/
static void i40e_inc_ntc(struct i40e_ring *rx_ring)
{
u32 ntc = rx_ring->next_to_clean + 1;
ntc = (ntc < rx_ring->count) ? ntc : 0;
rx_ring->next_to_clean = ntc;
prefetch(I40E_RX_DESC(rx_ring, ntc));
}
/**
* i40e_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
* @rx_ring: rx descriptor ring to transact packets on

13
drivers/net/ethernet/intel/i40e/i40e_txrx_common.h
View File

@ -99,19 +99,6 @@ static inline bool i40e_rx_is_programming_status(u64 qword1)
return qword1 & I40E_RXD_QW1_LENGTH_SPH_MASK;
}
/**
* i40e_inc_ntc: Advance the next_to_clean index
* @rx_ring: Rx ring
**/
static inline void i40e_inc_ntc(struct i40e_ring *rx_ring)
{
u32 ntc = rx_ring->next_to_clean + 1;
ntc = (ntc < rx_ring->count) ? ntc : 0;
rx_ring->next_to_clean = ntc;
prefetch(I40E_RX_DESC(rx_ring, ntc));
}
void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring);
void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring);
bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi);

12
drivers/net/ethernet/intel/i40e/i40e_xsk.c
View File

@ -257,6 +257,18 @@ static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
return skb;
}
/**
* i40e_inc_ntc: Advance the next_to_clean index
* @rx_ring: Rx ring
**/
static void i40e_inc_ntc(struct i40e_ring *rx_ring)
{
u32 ntc = rx_ring->next_to_clean + 1;
ntc = (ntc < rx_ring->count) ? ntc : 0;
rx_ring->next_to_clean = ntc;
}
/**
* i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
* @rx_ring: Rx ring