1 /*- 2 * BSD LICENSE 3 * 4 * Copyright (c) 2016-2017 Solarflare Communications Inc. 5 * All rights reserved. 6 * 7 * This software was jointly developed between OKTET Labs (under contract 8 * for Solarflare) and Solarflare Communications, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright notice, 14 * this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 20 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 21 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 26 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 27 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 28 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 29 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef _SFC_TWEAK_H_ 33 #define _SFC_TWEAK_H_ 34 35 /* 36 * The header is intended to collect defines/constants which could be 37 * tweaked to improve the PMD performance characteristics depending on 38 * the usecase or requirements (CPU load, packet rate, latency). 39 */ 40 41 /** 42 * Number of Rx descriptors in the bulk submitted on Rx ring refill. 43 */ 44 #define SFC_RX_REFILL_BULK (RTE_CACHE_LINE_SIZE / sizeof(efx_qword_t)) 45 46 /** 47 * Make the transmit path reap at least one time per a burst; 48 * this improves cache locality because the same mbufs may be used to send 49 * subsequent bursts in certain cases because of well-timed reap 50 */ 51 #define SFC_TX_XMIT_PKTS_REAP_AT_LEAST_ONCE 0 52 53 /** Default free threshold follows recommendations from DPDK documentation */ 54 #define SFC_TX_DEFAULT_FREE_THRESH 32 55 56 #endif /* _SFC_TWEAK_H_ */ 57