ceph/src/seastar/dpdk/drivers/net/sfc/sfc_tweak.h

   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 /**
  38  * Default head-of-line block timeout to wait for Rx descriptor before
  39  * packet drop because of no descriptors available.
  40  *
  41  * DPDK FW variant only with equal stride super-buffer Rx mode.
  42  */
  43 #define SFC_RXD_WAIT_TIMEOUT_NS_DEF     (200U * 1000)
  44
  45 #endif /* _SFC_TWEAK_H_ */