Messages in this thread | | | Subject | Re: [PATCH net v3] ixgbe: fix double clean of tx descriptors with xdp | From | Björn Töpel <> | Date | Fri, 23 Aug 2019 08:10:25 +0200 |
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On 2019-08-22 19:32, William Tu wrote: > On Thu, Aug 22, 2019 at 10:21 AM Alexander Duyck > <alexander.duyck@gmail.com> wrote: >> >> On Thu, Aug 22, 2019 at 10:12 AM Ilya Maximets <i.maximets@samsung.com> wrote: >>> >>> Tx code doesn't clear the descriptors' status after cleaning. >>> So, if the budget is larger than number of used elems in a ring, some >>> descriptors will be accounted twice and xsk_umem_complete_tx will move >>> prod_tail far beyond the prod_head breaking the completion queue ring. >>> >>> Fix that by limiting the number of descriptors to clean by the number >>> of used descriptors in the tx ring. >>> >>> 'ixgbe_clean_xdp_tx_irq()' function refactored to look more like >>> 'ixgbe_xsk_clean_tx_ring()' since we're allowed to directly use >>> 'next_to_clean' and 'next_to_use' indexes. >>> >>> Fixes: 8221c5eba8c1 ("ixgbe: add AF_XDP zero-copy Tx support") >>> Signed-off-by: Ilya Maximets <i.maximets@samsung.com> >>> --- >>> >>> Version 3: >>> * Reverted some refactoring made for v2. >>> * Eliminated 'budget' for tx clean. >>> * prefetch returned. >>> >>> Version 2: >>> * 'ixgbe_clean_xdp_tx_irq()' refactored to look more like >>> 'ixgbe_xsk_clean_tx_ring()'. >>> >>> drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 29 ++++++++------------ >>> 1 file changed, 11 insertions(+), 18 deletions(-) >> >> Thanks for addressing my concerns. >> >> Acked-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> > > Thanks. > > Tested-by: William Tu <u9012063@gmail.com> >
Will, thanks for testing! For this patch, did you notice any performance degradation?
Cheers, Björn
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