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: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
brakmo 2019-05-28 16:59:39 -07:00 committed by Alexei Starovoitov
parent 956fe21908
commit ffd81558d5
4 changed files with 45 additions and 12 deletions

View File

@ -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

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@ -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':

View File

@ -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;

View File

@ -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";