> -----Original Message----- > From: Intel-wired-lan <[email protected]> On Behalf Of > Magnus Karlsson > Sent: Tuesday, June 23, 2020 2:44 AM > To: Karlsson, Magnus <[email protected]>; Topel, Bjorn > <[email protected]>; [email protected]; Kirsher, Jeffrey T > <[email protected]>; Samudrala, Sridhar > <[email protected]> > Cc: [email protected]; Fijalkowski, Maciej > <[email protected]>; [email protected] > Subject: [Intel-wired-lan] [PATCH net-next v2 1/3] i40e: optimize AF_XDP Tx > completion path > > Improve the performance of the AF_XDP zero-copy Tx completion path. > When there are no XDP buffers being sent using XDP_TX or XDP_REDIRECT, > we do not have go through the SW ring to clean up any entries since the > AF_XDP path does not use these. In these cases, just fast forward the next- > to-use counter and skip going through the SW ring. The limit on the > maximum number of entries to complete is also removed since the algorithm > is now O(1). To simplify the code path, the maximum number of entries to > complete for the XDP path is therefore also increased from 256 to 512 (the > default number of Tx HW descriptors). This should be fine since the > completion in the XDP path is faster than in the SKB path that has 256 as the > maximum number. > > This patch provides around 4% throughput improvement for the l2fwd > application in xdpsock on my machine. > > Signed-off-by: Magnus Karlsson <[email protected]> > --- > drivers/net/ethernet/intel/i40e/i40e_txrx.c | 3 +- > drivers/net/ethernet/intel/i40e/i40e_txrx.h | 1 + > drivers/net/ethernet/intel/i40e/i40e_xsk.c | 43 +++++++++++++++---------- > ---- drivers/net/ethernet/intel/i40e/i40e_xsk.h | 3 +- > 4 files changed, 27 insertions(+), 23 deletions(-)
Tested-by: Andrew Bowers <[email protected]>
