tcp_ratelimit.h

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/*-
 *
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2018-2020
 *      Netflix Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * __FBSDID("$FreeBSD$");
 *
 */
#ifndef __tcp_ratelimit_h__
#define __tcp_ratelimit_h__
 
struct m_snd_tag;
 
/* Flags on an individual rate */
#define HDWRPACE_INITED         0x0001
#define HDWRPACE_TAGPRESENT     0x0002
#define HDWRPACE_IFPDEPARTED    0x0004
struct tcp_hwrate_limit_table {
        const struct tcp_rate_set *ptbl;        /* Pointer to parent table */
        struct m_snd_tag *tag;  /* Send tag if needed (chelsio) */
        long     rate;          /* Rate we get in Bytes per second (Bps) */
        long     using;         /* How many flows are using this hdwr rate. */
        long     rs_num_enobufs;
        uint32_t time_between;  /* Time-Gap between packets at this rate */
        uint32_t flags;
};
 
/* Rateset flags */
#define RS_IS_DEFF      0x0001  /* Its a lagg, do a double lookup */
#define RS_IS_INTF      0x0002  /* Its a plain interface */
#define RS_NO_PRE       0x0004  /* The interfacd has set rates */
#define RS_INT_TBL      0x0010  /*
                                 * The table is the internal version
                                 * which has special setup requirements.
                                 */
#define RS_IS_DEAD      0x0020  /* The RS is dead list */
#define RS_FUNERAL_SCHD 0x0040  /* Is a epoch call scheduled to bury this guy?*/
#define RS_INTF_NO_SUP  0x0100  /* The interface does not support the ratelimiting */
 
struct tcp_rate_set {
        struct sysctl_ctx_list sysctl_ctx;
        CK_LIST_ENTRY(tcp_rate_set) next;
        struct ifnet *rs_ifp;
        struct tcp_hwrate_limit_table *rs_rlt;
        uint64_t rs_flows_using;
        uint64_t rs_flow_limit;
        uint32_t rs_if_dunit;
        int rs_rate_cnt;
        int rs_min_seg;
        int rs_highest_valid;
        int rs_lowest_valid;
        int rs_disable;
        int rs_flags;
        struct epoch_context rs_epoch_ctx;
};
 
CK_LIST_HEAD(head_tcp_rate_set, tcp_rate_set);
 
/* Request flags */
#define RS_PACING_EXACT_MATCH   0x0001  /* Need an exact match for rate */
#define RS_PACING_GT            0x0002  /* Greater than requested */
#define RS_PACING_GEQ           0x0004  /* Greater than or equal too */
#define RS_PACING_LT            0x0008  /* Less than requested rate */
#define RS_PACING_SUB_OK        0x0010  /* If a rate can't be found get the
                                         * next best rate (highest or lowest). */
#ifdef _KERNEL
#ifndef ETHERNET_SEGMENT_SIZE
#define ETHERNET_SEGMENT_SIZE 1514
#endif
#ifdef RATELIMIT
#define DETAILED_RATELIMIT_SYSCTL 1     /*
                                         * Undefine this if you don't want
                                         * detailed rates to appear in
                                         * net.inet.tcp.rl.
                                         * With the defintion each rate
                                         * shows up in your sysctl tree
                                         * this can be big.
                                         */
uint64_t inline
tcp_hw_highest_rate(const struct tcp_hwrate_limit_table *rle)
{
        return (rle->ptbl->rs_rlt[rle->ptbl->rs_highest_valid].rate);
}
 
uint64_t
tcp_hw_highest_rate_ifp(struct ifnet *ifp, struct inpcb *inp);
 
const struct tcp_hwrate_limit_table *
tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp,
    uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate);
 
const struct tcp_hwrate_limit_table *
tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte,
    struct tcpcb *tp, struct ifnet *ifp,
    uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate);
void
tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte,
    struct tcpcb *tp);
#else
static inline const struct tcp_hwrate_limit_table *
tcp_set_pacing_rate(struct tcpcb *tp, struct ifnet *ifp,
    uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate)
{
        if (error)
                *error = EOPNOTSUPP;
        return (NULL);
}
 
static inline const struct tcp_hwrate_limit_table *
tcp_chg_pacing_rate(const struct tcp_hwrate_limit_table *crte,
    struct tcpcb *tp, struct ifnet *ifp,
    uint64_t bytes_per_sec, int flags, int *error, uint64_t *lower_rate)
{
        if (error)
                *error = EOPNOTSUPP;
        return (NULL);
}
 
static inline void
tcp_rel_pacing_rate(const struct tcp_hwrate_limit_table *crte,
    struct tcpcb *tp)
{
        return;
}
 
static uint64_t inline
tcp_hw_highest_rate(const struct tcp_hwrate_limit_table *rle)
{
        return (0);
}
 
static uint64_t inline
tcp_hw_highest_rate_ifp(struct ifnet *ifp, struct inpcb *inp)
{
        return (0);
}
 
 
#endif
/*
 * Given a b/w and a segsiz, and optional hardware
 * rate limit, return the ideal size to burst
 * out at once. Note the parameter can_use_1mss
 * dictates if the transport will tolerate a 1mss
 * limit, if not it will bottom out at 2mss (think
 * delayed ack).
 */
uint32_t
tcp_get_pacing_burst_size(struct tcpcb *tp, uint64_t bw, uint32_t segsiz, int can_use_1mss,
   const struct tcp_hwrate_limit_table *te, int *err);
 
 
void
tcp_rl_log_enobuf(const struct tcp_hwrate_limit_table *rte);
 
#endif
#endif