On Mon, Jan 05, 2026 at 05:47:31PM +0000, Bruce Richardson wrote: > On Fri, Dec 12, 2025 at 11:11:36AM +0000, Morten Brørup wrote: > > When fast release of mbufs is enabled, the mempool to free the mbufs to > > was determined by looking at the pool pointer of the first mbuf in the > > burst being freed, potentially costing a cache miss. > > > > This patch adds a mbuf fast release mempool pointer to the common transmit > > queue structure, so reading the mbufs during fast release is avoided. > > The pointer in located a cache line already being accessed, > > and is only set once, when the first mbuf ever is released. > > > > The fast release mempool pointer also indicates if fast release is > > enabled, so this pointer is checked instead of the > > RTE_ETH_TX_OFFLOAD_MBUF_FAST_FREE flag in the offloads field in the > > transmit queue structure. > > > > The same optimizations were applied to mbuf recycle. > > > > For the ice driver, prefetcing the mbufs when fast release of mbufs is > > enabled became superflouous, and has been moved into the branch for normal > > mbuf release. > > > > For the i40e driver, prefetcing the mbufs when fast release of mbufs is > > enabled was already superflouous, and has been moved into the branch for > > normal mbuf release. > > > > Signed-off-by: Morten Brørup <[email protected]> > > --- > > drivers/net/intel/common/recycle_mbufs.h | 10 +++++--- > > drivers/net/intel/common/tx.h | 14 +++++++++-- > > drivers/net/intel/cpfl/cpfl_rxtx.c | 2 ++ > > drivers/net/intel/i40e/i40e_rxtx.c | 31 +++++++++++++++--------- > > drivers/net/intel/iavf/iavf_rxtx.c | 2 ++ > > drivers/net/intel/ice/ice_rxtx.c | 15 +++++++++--- > > drivers/net/intel/idpf/idpf_rxtx.c | 2 ++ > > drivers/net/intel/ixgbe/ixgbe_rxtx.c | 2 ++ > > 8 files changed, 57 insertions(+), 21 deletions(-) > > > > This change seems reasonable to me. Ran a quick test with 2 x 100G ports > and saw no degradation in performance, and it seems to improve performance > by maybe 1-2%, in that quick test. > > Therefore: > Acked-by: Bruce Richardson <[email protected]> > Applied to next-net-intel.
Thanks, /Bruce
