> -----Original Message----- > From: Ruifeng Wang <[email protected]> > Sent: Tuesday, January 4, 2022 5:01 AM > To: Matan Azrad <[email protected]>; Slava Ovsiienko > <[email protected]> > Cc: [email protected]; [email protected]; [email protected]; > [email protected]; Ruifeng Wang <[email protected]> > Subject: [PATCH] net/mlx5: fix risk in Rx descriptor read in NEON vector path > > In NEON vector PMD, vector load loads two contiguous 8B of > descriptor data into vector register. Given vector load ensures no > 16B atomicity, read of the word that includes op_own field could be > reordered after read of other words. In this case, some words could > contain invalid data. > > Reloaded qword0 after read barrier to update vector register. This > ensures that the fetched data is correct. > > Testpmd single core test on N1SDP/ThunderX2 showed no performance > drop. > > Fixes: 1742c2d9fab0 ("net/mlx5: fix synchronization on polling Rx > completions") > Cc: [email protected] > > Signed-off-by: Ruifeng Wang <[email protected]> > ---
Tested with BlueField-2 and didn't see a performance impact. Tested-by: Ali Alnubani <[email protected]> Thanks, Ali
