1 /* SPDX-License-Identifier: BSD-3-Clause 2 * 3 * Copyright (c) 2016-2018 Solarflare Communications Inc. 4 * All rights reserved. 5 * 6 * This software was jointly developed between OKTET Labs (under contract 7 * for Solarflare) and Solarflare Communications, Inc. 8 */ 9 10 #ifndef _SFC_TWEAK_H_ 11 #define _SFC_TWEAK_H_ 12 13 /* 14 * The header is intended to collect defines/constants which could be 15 * tweaked to improve the PMD performance characteristics depending on 16 * the usecase or requirements (CPU load, packet rate, latency). 17 */ 18 19 /** 20 * Number of Rx descriptors in the bulk submitted on Rx ring refill. 21 */ 22 #define SFC_RX_REFILL_BULK (RTE_CACHE_LINE_SIZE / sizeof(efx_qword_t)) 23 24 /** 25 * Make the transmit path reap at least one time per a burst; 26 * this improves cache locality because the same mbufs may be used to send 27 * subsequent bursts in certain cases because of well-timed reap 28 */ 29 #define SFC_TX_XMIT_PKTS_REAP_AT_LEAST_ONCE 0 30 31 /** Default free threshold follows recommendations from DPDK documentation */ 32 #define SFC_TX_DEFAULT_FREE_THRESH 32 33 34 /** Number of mbufs to be freed in bulk in a single call */ 35 #define SFC_TX_REAP_BULK_SIZE 32 36 37 #endif /* _SFC_TWEAK_H_ */ 38