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17d370a70b
Often times the compilers are not able to expand two consecutive 32-bit writes into one 64-bit on the corresponding architectures. This applies to xdp_init_buff() called for every received frame (or at least once per each 64 frames when the frag size is fixed). Move the not-so-pretty hack from libeth_xdp straight to xdp_init_buff(), but using a proper union around ::frame_sz and ::flags. The optimization is limited to LE architectures due to the structure layout. One simple example from idpf with the XDP series applied (Clang 22-git, CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE => -O2): add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-27 (-27) Function old new delta idpf_vport_splitq_napi_poll 5076 5049 -27 The perf difference with XDP_DROP is around +0.8-1% which I see as more than satisfying. Suggested-by: Simon Horman <horms@kernel.org> Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Tested-by: Ramu R <ramu.r@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>