Commit ffd81558 authored by brakmo's avatar brakmo Committed by Alexei Starovoitov
Browse files

bpf: Add cn support to hbm_out_kern.c 



Update hbm_out_kern.c to support returning cn notifications.
Also updates relevant files to allow disabling cn notifications.

Signed-off-by: default avatarLawrence Brakmo <brakmo@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 956fe219

samples/bpf/do_hbm_test.sh

+7 −3
Original line number Diff line number Diff line
@@ -13,10 +13,10 @@ Usage() { 
  echo "egress or ingress bandwidht. It then uses iperf3 or netperf to create"

  echo "loads. The output is the goodput in Mbps (unless -D was used)."

  echo ""

  echo "USAGE: $name [out] [-b=<prog>|--bpf=<prog>] [-c=<cc>|--cc=<cc>] [-D]"

  echo "             [-d=<delay>|--delay=<delay>] [--debug] [-E]"

  echo "USAGE: $name [out] [-b=<prog>|--bpf=<prog>] [-c=<cc>|--cc=<cc>]"

  echo "             [-D] [-d=<delay>|--delay=<delay>] [--debug] [-E]"

  echo "             [-f=<#flows>|--flows=<#flows>] [-h] [-i=<id>|--id=<id >]"

  echo "             [-l] [-N] [-p=<port>|--port=<port>] [-P]"

  echo "             [-l] [-N] [--no_cn] [-p=<port>|--port=<port>] [-P]"

  echo "             [-q=<qdisc>] [-R] [-s=<server>|--server=<server]"

  echo "             [-S|--stats] -t=<time>|--time=<time>] [-w] [cubic|dctcp]"

  echo "  Where:"
@@ -33,6 +33,7 @@ Usage() { 
  echo "    -f or --flows     number of concurrent flows (default=1)"

  echo "    -i or --id        cgroup id (an integer, default is 1)"

  echo "    -N                use netperf instead of iperf3"

  echo "    --no_cn           Do not return CN notifications"

  echo "    -l                do not limit flows using loopback"

  echo "    -h                Help"

  echo "    -p or --port      iperf3 port (default is 5201)"
@@ -115,6 +116,9 @@ processArgs () { 
    -c=*|--cc=*)

      cc="${i#*=}"

      ;;

    --no_cn)

      flags="$flags --no_cn"

      ;;

    --debug)

      flags="$flags -d"

      debug_flag=1

samples/bpf/hbm.c

+15 −3
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
 *    -l	Also limit flows doing loopback

 *    -n <#>	To create cgroup \"/hbm#\" and attach prog

 *		Default is /hbm1

 *    --no_cn   Do not return cn notifications

 *    -r <rate>	Rate limit in Mbps

 *    -s	Get HBM stats (marked, dropped, etc.)

 *    -t <time>	Exit after specified seconds (default is 0)
@@ -42,6 +43,7 @@ 


#include <linux/bpf.h>

#include <bpf/bpf.h>

#include <getopt.h>



#include "bpf_load.h"

#include "bpf_rlimit.h"
@@ -59,6 +61,7 @@ bool stats_flag; 
bool loopback_flag;

bool debugFlag;

bool work_conserving_flag;

bool no_cn_flag;



static void Usage(void);

static void read_trace_pipe2(void);
@@ -185,6 +188,7 @@ static int run_bpf_prog(char *prog, int cg_id) 
	qstats.rate = rate;

	qstats.stats = stats_flag ? 1 : 0;

	qstats.loopback = loopback_flag ? 1 : 0;

	qstats.no_cn = no_cn_flag ? 1 : 0;

	if (bpf_map_update_elem(map_fd, &key, &qstats, BPF_ANY)) {

		printf("ERROR: Could not update map element\n");

		goto err;
@@ -366,14 +370,15 @@ static void Usage(void) 
{

	printf("This program loads a cgroup skb BPF program to enforce\n"

	       "cgroup output (egress) bandwidth limits.\n\n"

	       "USAGE: hbm [-o] [-d]  [-l] [-n <id>] [-r <rate>] [-s]\n"

	       "           [-t <secs>] [-w] [-h] [prog]\n"

	       "USAGE: hbm [-o] [-d]  [-l] [-n <id>] [--no_cn] [-r <rate>]\n"

	       "           [-s] [-t <secs>] [-w] [-h] [prog]\n"

	       "  Where:\n"

	       "    -o         indicates egress direction (default)\n"

	       "    -d         print BPF trace debug buffer\n"

	       "    -l         also limit flows using loopback\n"

	       "    -n <#>     to create cgroup \"/hbm#\" and attach prog\n"

	       "               Default is /hbm1\n"

	       "    --no_cn    disable CN notifcations\n"

	       "    -r <rate>  Rate in Mbps\n"

	       "    -s         Update HBM stats\n"

	       "    -t <time>  Exit after specified seconds (default is 0)\n"
@@ -393,9 +398,16 @@ int main(int argc, char **argv) 
	int  k;

	int cg_id = 1;

	char *optstring = "iodln:r:st:wh";

	struct option loptions[] = {

		{"no_cn", 0, NULL, 1},

		{NULL, 0, NULL, 0}

	};



	while ((k = getopt(argc, argv, optstring)) != -1) {

	while ((k = getopt_long(argc, argv, optstring, loptions, NULL)) != -1) {

		switch (k) {

		case 1:

			no_cn_flag = true;

			break;

		case'o':

			break;

		case 'd':

samples/bpf/hbm.h

+2 −1
Original line number Diff line number Diff line
@@ -19,7 +19,8 @@ struct hbm_vqueue { 
struct hbm_queue_stats {

	unsigned long rate;		/* in Mbps*/

	unsigned long stats:1,		/* get HBM stats (marked, dropped,..) */

		loopback:1;		/* also limit flows using loopback */

		loopback:1,		/* also limit flows using loopback */

		no_cn:1;		/* do not use cn flags */

	unsigned long long pkts_marked;

	unsigned long long bytes_marked;

	unsigned long long pkts_dropped;

samples/bpf/hbm_out_kern.c

+21 −5
Original line number Diff line number Diff line
@@ -119,13 +119,16 @@ int _hbm_out_cg(struct __sk_buff *skb) 
	// Set flags (drop, congestion, cwr)

	// Dropping => we are congested, so ignore congestion flag

	if (credit < -DROP_THRESH ||

	    (len > LARGE_PKT_THRESH &&

	     credit < -LARGE_PKT_DROP_THRESH)) {

		// Very congested, set drop flag

	    (len > LARGE_PKT_THRESH && credit < -LARGE_PKT_DROP_THRESH)) {

		// Very congested, set drop packet

		drop_flag = true;

		if (pkti.ecn)

			congestion_flag = true;

		else if (pkti.is_tcp)

			cwr_flag = true;

	} else if (credit < 0) {

		// Congested, set congestion flag

		if (pkti.ecn) {

		if (pkti.ecn || pkti.is_tcp) {

			if (credit < -MARK_THRESH)

				congestion_flag = true;

			else
@@ -137,7 +140,15 @@ int _hbm_out_cg(struct __sk_buff *skb) 


	if (congestion_flag) {

		if (!bpf_skb_ecn_set_ce(skb)) {

			if (len > LARGE_PKT_THRESH) {

			if (pkti.is_tcp) {

				unsigned int rand = bpf_get_prandom_u32();



				if (-credit >= MARK_THRESH +

				    (rand % MARK_REGION_SIZE)) {

					// Do congestion control

					cwr_flag = true;

				}

			} else if (len > LARGE_PKT_THRESH) {

				// Problem if too many small packets?

				drop_flag = true;

			}
@@ -146,12 +157,17 @@ int _hbm_out_cg(struct __sk_buff *skb) 


	if (drop_flag)

		rv = DROP_PKT;

	if (qsp != NULL)

		if (qsp->no_cn)

			cwr_flag = false;



	hbm_update_stats(qsp, len, curtime, congestion_flag, drop_flag);



	if (rv == DROP_PKT)

		__sync_add_and_fetch(&(qdp->credit), len);



	if (cwr_flag)

		rv |= 2;

	return rv;

}

char _license[] SEC("license") = "GPL";