Revision 78c906e430b13d30a8cfbdef4ccbbe1686841a9e authored by Vlad Buslov on 31 August 2020, 13:17:29 UTC, committed by Saeed Mahameed on 05 November 2020, 20:17:05 UTC
In functions mlx5e_route_lookup_ipv{4|6}() route_dev can be arbitrary net
device and not necessary mlx5 eswitch port representor. As such, in order
to ensure that route_dev is not destroyed concurrent the code needs either
explicitly take reference to the device before releasing reference to
rtable instance or ensure that caller holds rtnl lock. First approach is
chosen as a fix since rtnl lock dependency was intentionally removed from
mlx5 TC layer.

To prevent unprotected usage of route_dev in encap code take a reference to
the device before releasing rt. Don't save direct pointer to the device in
mlx5_encap_entry structure and use ifindex instead. Modify users of
route_dev pointer to properly obtain the net device instance from its
ifindex.

Fixes: 61086f391044 ("net/mlx5e: Protect encap hash table with mutex")
Fixes: 6707f74be862 ("net/mlx5e: Update hw flows when encap source mac changed")
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
1 parent e68e28b
Raw File
tcp_highspeed.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Sally Floyd's High Speed TCP (RFC 3649) congestion control
 *
 * See https://www.icir.org/floyd/hstcp.html
 *
 * John Heffner <jheffner@psc.edu>
 */

#include <linux/module.h>
#include <net/tcp.h>

/* From AIMD tables from RFC 3649 appendix B,
 * with fixed-point MD scaled <<8.
 */
static const struct hstcp_aimd_val {
	unsigned int cwnd;
	unsigned int md;
} hstcp_aimd_vals[] = {
	{     38,  128, /*  0.50 */ },
	{    118,  112, /*  0.44 */ },
	{    221,  104, /*  0.41 */ },
	{    347,   98, /*  0.38 */ },
	{    495,   93, /*  0.37 */ },
	{    663,   89, /*  0.35 */ },
	{    851,   86, /*  0.34 */ },
	{   1058,   83, /*  0.33 */ },
	{   1284,   81, /*  0.32 */ },
	{   1529,   78, /*  0.31 */ },
	{   1793,   76, /*  0.30 */ },
	{   2076,   74, /*  0.29 */ },
	{   2378,   72, /*  0.28 */ },
	{   2699,   71, /*  0.28 */ },
	{   3039,   69, /*  0.27 */ },
	{   3399,   68, /*  0.27 */ },
	{   3778,   66, /*  0.26 */ },
	{   4177,   65, /*  0.26 */ },
	{   4596,   64, /*  0.25 */ },
	{   5036,   62, /*  0.25 */ },
	{   5497,   61, /*  0.24 */ },
	{   5979,   60, /*  0.24 */ },
	{   6483,   59, /*  0.23 */ },
	{   7009,   58, /*  0.23 */ },
	{   7558,   57, /*  0.22 */ },
	{   8130,   56, /*  0.22 */ },
	{   8726,   55, /*  0.22 */ },
	{   9346,   54, /*  0.21 */ },
	{   9991,   53, /*  0.21 */ },
	{  10661,   52, /*  0.21 */ },
	{  11358,   52, /*  0.20 */ },
	{  12082,   51, /*  0.20 */ },
	{  12834,   50, /*  0.20 */ },
	{  13614,   49, /*  0.19 */ },
	{  14424,   48, /*  0.19 */ },
	{  15265,   48, /*  0.19 */ },
	{  16137,   47, /*  0.19 */ },
	{  17042,   46, /*  0.18 */ },
	{  17981,   45, /*  0.18 */ },
	{  18955,   45, /*  0.18 */ },
	{  19965,   44, /*  0.17 */ },
	{  21013,   43, /*  0.17 */ },
	{  22101,   43, /*  0.17 */ },
	{  23230,   42, /*  0.17 */ },
	{  24402,   41, /*  0.16 */ },
	{  25618,   41, /*  0.16 */ },
	{  26881,   40, /*  0.16 */ },
	{  28193,   39, /*  0.16 */ },
	{  29557,   39, /*  0.15 */ },
	{  30975,   38, /*  0.15 */ },
	{  32450,   38, /*  0.15 */ },
	{  33986,   37, /*  0.15 */ },
	{  35586,   36, /*  0.14 */ },
	{  37253,   36, /*  0.14 */ },
	{  38992,   35, /*  0.14 */ },
	{  40808,   35, /*  0.14 */ },
	{  42707,   34, /*  0.13 */ },
	{  44694,   33, /*  0.13 */ },
	{  46776,   33, /*  0.13 */ },
	{  48961,   32, /*  0.13 */ },
	{  51258,   32, /*  0.13 */ },
	{  53677,   31, /*  0.12 */ },
	{  56230,   30, /*  0.12 */ },
	{  58932,   30, /*  0.12 */ },
	{  61799,   29, /*  0.12 */ },
	{  64851,   28, /*  0.11 */ },
	{  68113,   28, /*  0.11 */ },
	{  71617,   27, /*  0.11 */ },
	{  75401,   26, /*  0.10 */ },
	{  79517,   26, /*  0.10 */ },
	{  84035,   25, /*  0.10 */ },
	{  89053,   24, /*  0.10 */ },
};

#define HSTCP_AIMD_MAX	ARRAY_SIZE(hstcp_aimd_vals)

struct hstcp {
	u32	ai;
};

static void hstcp_init(struct sock *sk)
{
	struct tcp_sock *tp = tcp_sk(sk);
	struct hstcp *ca = inet_csk_ca(sk);

	ca->ai = 0;

	/* Ensure the MD arithmetic works.  This is somewhat pedantic,
	 * since I don't think we will see a cwnd this large. :) */
	tp->snd_cwnd_clamp = min_t(u32, tp->snd_cwnd_clamp, 0xffffffff/128);
}

static void hstcp_cong_avoid(struct sock *sk, u32 ack, u32 acked)
{
	struct tcp_sock *tp = tcp_sk(sk);
	struct hstcp *ca = inet_csk_ca(sk);

	if (!tcp_is_cwnd_limited(sk))
		return;

	if (tcp_in_slow_start(tp))
		tcp_slow_start(tp, acked);
	else {
		/* Update AIMD parameters.
		 *
		 * We want to guarantee that:
		 *     hstcp_aimd_vals[ca->ai-1].cwnd <
		 *     snd_cwnd <=
		 *     hstcp_aimd_vals[ca->ai].cwnd
		 */
		if (tp->snd_cwnd > hstcp_aimd_vals[ca->ai].cwnd) {
			while (tp->snd_cwnd > hstcp_aimd_vals[ca->ai].cwnd &&
			       ca->ai < HSTCP_AIMD_MAX - 1)
				ca->ai++;
		} else if (ca->ai && tp->snd_cwnd <= hstcp_aimd_vals[ca->ai-1].cwnd) {
			while (ca->ai && tp->snd_cwnd <= hstcp_aimd_vals[ca->ai-1].cwnd)
				ca->ai--;
		}

		/* Do additive increase */
		if (tp->snd_cwnd < tp->snd_cwnd_clamp) {
			/* cwnd = cwnd + a(w) / cwnd */
			tp->snd_cwnd_cnt += ca->ai + 1;
			if (tp->snd_cwnd_cnt >= tp->snd_cwnd) {
				tp->snd_cwnd_cnt -= tp->snd_cwnd;
				tp->snd_cwnd++;
			}
		}
	}
}

static u32 hstcp_ssthresh(struct sock *sk)
{
	const struct tcp_sock *tp = tcp_sk(sk);
	struct hstcp *ca = inet_csk_ca(sk);

	/* Do multiplicative decrease */
	return max(tp->snd_cwnd - ((tp->snd_cwnd * hstcp_aimd_vals[ca->ai].md) >> 8), 2U);
}

static struct tcp_congestion_ops tcp_highspeed __read_mostly = {
	.init		= hstcp_init,
	.ssthresh	= hstcp_ssthresh,
	.undo_cwnd	= tcp_reno_undo_cwnd,
	.cong_avoid	= hstcp_cong_avoid,

	.owner		= THIS_MODULE,
	.name		= "highspeed"
};

static int __init hstcp_register(void)
{
	BUILD_BUG_ON(sizeof(struct hstcp) > ICSK_CA_PRIV_SIZE);
	return tcp_register_congestion_control(&tcp_highspeed);
}

static void __exit hstcp_unregister(void)
{
	tcp_unregister_congestion_control(&tcp_highspeed);
}

module_init(hstcp_register);
module_exit(hstcp_unregister);

MODULE_AUTHOR("John Heffner");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("High Speed TCP");
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