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samples/bpf: add cpumap sample program xdp_redirect_cpu

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This sample program show how to use cpumap and the associated
tracepoints.

It provides command line stats, which shows how the XDP-RX process,
cpumap-enqueue and cpumap kthread dequeue is cooperating on a per CPU
basis.  It also utilize the xdp_exception and xdp_redirect_err
transpoints to allow users quickly to identify setup issues.

One issue with ixgbe driver is that the driver reset the link when
loading XDP.  This reset the procfs smp_affinity settings.  Thus,
after loading the program, these must be reconfigured.  The easiest
workaround it to reduce the RX-queue to e.g. two via:

 # ethtool --set-channels ixgbe1 combined 2

And then add CPUs above 0 and 1, like:

 # xdp_redirect_cpu --dev ixgbe1 --prog 2 --cpu 2 --cpu 3 --cpu 4

Another issue with ixgbe is that the page recycle mechanism is tied to
the RX-ring size.  And the default setting of 512 elements is too
small.  This is the same issue with regular devmap XDP_REDIRECT.
To overcome this I've been using 1024 rx-ring size:

 # ethtool -G ixgbe1 rx 1024 tx 1024

V3:
 - whitespace cleanups
 - bpf tracepoint cannot access top part of struct

V4:
 - report on kthread sched events, according to tracepoint change
 - report average bulk enqueue size

V5:
 - bpf_map_lookup_elem on cpumap not allowed from bpf_prog
   use separate map to mark CPUs not available

V6:
 - correct kthread sched summary output

V7:
 - Added a --stress-mode for concurrently changing underlying cpumap

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jesper Dangaard Brouer 2017-10-16 12:19:49 +02:00 committed by David S. Miller
parent f9419f7bd7
commit fad3917e36
3 changed files with 1310 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
samples/bpf/Makefile
View File

@ -39,6 +39,7 @@ hostprogs-y += per_socket_stats_example
hostprogs-y += load_sock_ops hostprogs-y += load_sock_ops
hostprogs-y += xdp_redirect hostprogs-y += xdp_redirect
hostprogs-y += xdp_redirect_map hostprogs-y += xdp_redirect_map
hostprogs-y += xdp_redirect_cpu
hostprogs-y += xdp_monitor hostprogs-y += xdp_monitor
hostprogs-y += syscall_tp hostprogs-y += syscall_tp
@ -84,6 +85,7 @@ test_map_in_map-objs := bpf_load.o $(LIBBPF) test_map_in_map_user.o
per_socket_stats_example-objs := $(LIBBPF) cookie_uid_helper_example.o per_socket_stats_example-objs := $(LIBBPF) cookie_uid_helper_example.o
xdp_redirect-objs := bpf_load.o $(LIBBPF) xdp_redirect_user.o xdp_redirect-objs := bpf_load.o $(LIBBPF) xdp_redirect_user.o
xdp_redirect_map-objs := bpf_load.o $(LIBBPF) xdp_redirect_map_user.o xdp_redirect_map-objs := bpf_load.o $(LIBBPF) xdp_redirect_map_user.o
xdp_redirect_cpu-objs := bpf_load.o $(LIBBPF) xdp_redirect_cpu_user.o
xdp_monitor-objs := bpf_load.o $(LIBBPF) xdp_monitor_user.o xdp_monitor-objs := bpf_load.o $(LIBBPF) xdp_monitor_user.o
syscall_tp-objs := bpf_load.o $(LIBBPF) syscall_tp_user.o syscall_tp-objs := bpf_load.o $(LIBBPF) syscall_tp_user.o
@ -129,6 +131,7 @@ always += tcp_iw_kern.o
always += tcp_clamp_kern.o always += tcp_clamp_kern.o
always += xdp_redirect_kern.o always += xdp_redirect_kern.o
always += xdp_redirect_map_kern.o always += xdp_redirect_map_kern.o
always += xdp_redirect_cpu_kern.o
always += xdp_monitor_kern.o always += xdp_monitor_kern.o
always += syscall_tp_kern.o always += syscall_tp_kern.o
@ -169,6 +172,7 @@ HOSTLOADLIBES_xdp_tx_iptunnel += -lelf
HOSTLOADLIBES_test_map_in_map += -lelf HOSTLOADLIBES_test_map_in_map += -lelf
HOSTLOADLIBES_xdp_redirect += -lelf HOSTLOADLIBES_xdp_redirect += -lelf
HOSTLOADLIBES_xdp_redirect_map += -lelf HOSTLOADLIBES_xdp_redirect_map += -lelf
HOSTLOADLIBES_xdp_redirect_cpu += -lelf
HOSTLOADLIBES_xdp_monitor += -lelf HOSTLOADLIBES_xdp_monitor += -lelf
HOSTLOADLIBES_syscall_tp += -lelf HOSTLOADLIBES_syscall_tp += -lelf

609
samples/bpf/xdp_redirect_cpu_kern.c Normal file
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@ -0,0 +1,609 @@
/* XDP redirect to CPUs via cpumap (BPF_MAP_TYPE_CPUMAP)
*
* GPLv2, Copyright(c) 2017 Jesper Dangaard Brouer, Red Hat, Inc.
*/
#include <uapi/linux/if_ether.h>
#include <uapi/linux/if_packet.h>
#include <uapi/linux/if_vlan.h>
#include <uapi/linux/ip.h>
#include <uapi/linux/ipv6.h>
#include <uapi/linux/in.h>
#include <uapi/linux/tcp.h>
#include <uapi/linux/udp.h>
#include <uapi/linux/bpf.h>
#include "bpf_helpers.h"
#define MAX_CPUS 12 /* WARNING - sync with _user.c */
/* Special map type that can XDP_REDIRECT frames to another CPU */
struct bpf_map_def SEC("maps") cpu_map = {
.type = BPF_MAP_TYPE_CPUMAP,
.key_size = sizeof(u32),
.value_size = sizeof(u32),
.max_entries = MAX_CPUS,
};
/* Common stats data record to keep userspace more simple */
struct datarec {
__u64 processed;
__u64 dropped;
__u64 issue;
};
/* Count RX packets, as XDP bpf_prog doesn't get direct TX-success
* feedback. Redirect TX errors can be caught via a tracepoint.
*/
struct bpf_map_def SEC("maps") rx_cnt = {
.type = BPF_MAP_TYPE_PERCPU_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(struct datarec),
.max_entries = 1,
};
/* Used by trace point */
struct bpf_map_def SEC("maps") redirect_err_cnt = {
.type = BPF_MAP_TYPE_PERCPU_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(struct datarec),
.max_entries = 2,
/* TODO: have entries for all possible errno's */
};
/* Used by trace point */
struct bpf_map_def SEC("maps") cpumap_enqueue_cnt = {
.type = BPF_MAP_TYPE_PERCPU_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(struct datarec),
.max_entries = MAX_CPUS,
};
/* Used by trace point */
struct bpf_map_def SEC("maps") cpumap_kthread_cnt = {
.type = BPF_MAP_TYPE_PERCPU_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(struct datarec),
.max_entries = 1,
};
/* Set of maps controlling available CPU, and for iterating through
* selectable redirect CPUs.
*/
struct bpf_map_def SEC("maps") cpus_available = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(u32),
.max_entries = MAX_CPUS,
};
struct bpf_map_def SEC("maps") cpus_count = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(u32),
.max_entries = 1,
};
struct bpf_map_def SEC("maps") cpus_iterator = {
.type = BPF_MAP_TYPE_PERCPU_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(u32),
.max_entries = 1,
};
/* Used by trace point */
struct bpf_map_def SEC("maps") exception_cnt = {
.type = BPF_MAP_TYPE_PERCPU_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(struct datarec),
.max_entries = 1,
};
/* Helper parse functions */
/* Parse Ethernet layer 2, extract network layer 3 offset and protocol
*
* Returns false on error and non-supported ether-type
*/
struct vlan_hdr {
__be16 h_vlan_TCI;
__be16 h_vlan_encapsulated_proto;
};
static __always_inline
bool parse_eth(struct ethhdr *eth, void *data_end,
u16 *eth_proto, u64 *l3_offset)
{
u16 eth_type;
u64 offset;
offset = sizeof(*eth);
if ((void *)eth + offset > data_end)
return false;
eth_type = eth->h_proto;
/* Skip non 802.3 Ethertypes */
if (unlikely(ntohs(eth_type) < ETH_P_802_3_MIN))
return false;
/* Handle VLAN tagged packet */
if (eth_type == htons(ETH_P_8021Q) || eth_type == htons(ETH_P_8021AD)) {
struct vlan_hdr *vlan_hdr;
vlan_hdr = (void *)eth + offset;
offset += sizeof(*vlan_hdr);
if ((void *)eth + offset > data_end)
return false;
eth_type = vlan_hdr->h_vlan_encapsulated_proto;
}
/* TODO: Handle double VLAN tagged packet */
*eth_proto = ntohs(eth_type);
*l3_offset = offset;
return true;
}
static __always_inline
u16 get_dest_port_ipv4_udp(struct xdp_md *ctx, u64 nh_off)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct iphdr *iph = data + nh_off;
struct udphdr *udph;
u16 dport;
if (iph + 1 > data_end)
return 0;
if (!(iph->protocol == IPPROTO_UDP))
return 0;
udph = (void *)(iph + 1);
if (udph + 1 > data_end)
return 0;
dport = ntohs(udph->dest);
return dport;
}
static __always_inline
int get_proto_ipv4(struct xdp_md *ctx, u64 nh_off)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct iphdr *iph = data + nh_off;
if (iph + 1 > data_end)
return 0;
return iph->protocol;
}
static __always_inline
int get_proto_ipv6(struct xdp_md *ctx, u64 nh_off)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct ipv6hdr *ip6h = data + nh_off;
if (ip6h + 1 > data_end)
return 0;
return ip6h->nexthdr;
}
SEC("xdp_cpu_map0")
int xdp_prognum0_no_touch(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct datarec *rec;
u32 *cpu_selected;
u32 cpu_dest;
u32 key = 0;
/* Only use first entry in cpus_available */
cpu_selected = bpf_map_lookup_elem(&cpus_available, &key);
if (!cpu_selected)
return XDP_ABORTED;
cpu_dest = *cpu_selected;
/* Count RX packet in map */
rec = bpf_map_lookup_elem(&rx_cnt, &key);
if (!rec)
return XDP_ABORTED;
rec->processed++;
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
SEC("xdp_cpu_map1_touch_data")
int xdp_prognum1_touch_data(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct ethhdr *eth = data;
struct datarec *rec;
u32 *cpu_selected;
u32 cpu_dest;
u16 eth_type;
u32 key = 0;
/* Only use first entry in cpus_available */
cpu_selected = bpf_map_lookup_elem(&cpus_available, &key);
if (!cpu_selected)
return XDP_ABORTED;
cpu_dest = *cpu_selected;
/* Validate packet length is minimum Eth header size */
if (eth + 1 > data_end)
return XDP_ABORTED;
/* Count RX packet in map */
rec = bpf_map_lookup_elem(&rx_cnt, &key);
if (!rec)
return XDP_ABORTED;
rec->processed++;
/* Read packet data, and use it (drop non 802.3 Ethertypes) */
eth_type = eth->h_proto;
if (ntohs(eth_type) < ETH_P_802_3_MIN) {
rec->dropped++;
return XDP_DROP;
}
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
SEC("xdp_cpu_map2_round_robin")
int xdp_prognum2_round_robin(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct ethhdr *eth = data;
struct datarec *rec;
u32 cpu_dest;
u32 *cpu_lookup;
u32 key0 = 0;
u32 *cpu_selected;
u32 *cpu_iterator;
u32 *cpu_max;
u32 cpu_idx;
cpu_max = bpf_map_lookup_elem(&cpus_count, &key0);
if (!cpu_max)
return XDP_ABORTED;
cpu_iterator = bpf_map_lookup_elem(&cpus_iterator, &key0);
if (!cpu_iterator)
return XDP_ABORTED;
cpu_idx = *cpu_iterator;
*cpu_iterator += 1;
if (*cpu_iterator == *cpu_max)
*cpu_iterator = 0;
cpu_selected = bpf_map_lookup_elem(&cpus_available, &cpu_idx);
if (!cpu_selected)
return XDP_ABORTED;
cpu_dest = *cpu_selected;
/* Count RX packet in map */
rec = bpf_map_lookup_elem(&rx_cnt, &key0);
if (!rec)
return XDP_ABORTED;
rec->processed++;
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
SEC("xdp_cpu_map3_proto_separate")
int xdp_prognum3_proto_separate(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct ethhdr *eth = data;
u8 ip_proto = IPPROTO_UDP;
struct datarec *rec;
u16 eth_proto = 0;
u64 l3_offset = 0;
u32 cpu_dest = 0;
u32 cpu_idx = 0;
u32 *cpu_lookup;
u32 key = 0;
/* Count RX packet in map */
rec = bpf_map_lookup_elem(&rx_cnt, &key);
if (!rec)
return XDP_ABORTED;
rec->processed++;
if (!(parse_eth(eth, data_end, &eth_proto, &l3_offset)))
return XDP_PASS; /* Just skip */
/* Extract L4 protocol */
switch (eth_proto) {
case ETH_P_IP:
ip_proto = get_proto_ipv4(ctx, l3_offset);
break;
case ETH_P_IPV6:
ip_proto = get_proto_ipv6(ctx, l3_offset);
break;
case ETH_P_ARP:
cpu_idx = 0; /* ARP packet handled on separate CPU */
break;
default:
cpu_idx = 0;
}
/* Choose CPU based on L4 protocol */
switch (ip_proto) {
case IPPROTO_ICMP:
case IPPROTO_ICMPV6:
cpu_idx = 2;
break;
case IPPROTO_TCP:
cpu_idx = 0;
break;
case IPPROTO_UDP:
cpu_idx = 1;
break;
default:
cpu_idx = 0;
}
cpu_lookup = bpf_map_lookup_elem(&cpus_available, &cpu_idx);
if (!cpu_lookup)
return XDP_ABORTED;
cpu_dest = *cpu_lookup;
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
SEC("xdp_cpu_map4_ddos_filter_pktgen")
int xdp_prognum4_ddos_filter_pktgen(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct ethhdr *eth = data;
u8 ip_proto = IPPROTO_UDP;
struct datarec *rec;
u16 eth_proto = 0;
u64 l3_offset = 0;
u32 cpu_dest = 0;
u32 cpu_idx = 0;
u16 dest_port;
u32 *cpu_lookup;
u32 key = 0;
/* Count RX packet in map */
rec = bpf_map_lookup_elem(&rx_cnt, &key);
if (!rec)
return XDP_ABORTED;
rec->processed++;
if (!(parse_eth(eth, data_end, &eth_proto, &l3_offset)))
return XDP_PASS; /* Just skip */
/* Extract L4 protocol */
switch (eth_proto) {
case ETH_P_IP:
ip_proto = get_proto_ipv4(ctx, l3_offset);
break;
case ETH_P_IPV6:
ip_proto = get_proto_ipv6(ctx, l3_offset);
break;
case ETH_P_ARP:
cpu_idx = 0; /* ARP packet handled on separate CPU */
break;
default:
cpu_idx = 0;
}
/* Choose CPU based on L4 protocol */
switch (ip_proto) {
case IPPROTO_ICMP:
case IPPROTO_ICMPV6:
cpu_idx = 2;
break;
case IPPROTO_TCP:
cpu_idx = 0;
break;
case IPPROTO_UDP:
cpu_idx = 1;
/* DDoS filter UDP port 9 (pktgen) */
dest_port = get_dest_port_ipv4_udp(ctx, l3_offset);
if (dest_port == 9) {
if (rec)
rec->dropped++;
return XDP_DROP;
}
break;
default:
cpu_idx = 0;
}
cpu_lookup = bpf_map_lookup_elem(&cpus_available, &cpu_idx);
if (!cpu_lookup)
return XDP_ABORTED;
cpu_dest = *cpu_lookup;
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
char _license[] SEC("license") = "GPL";
/*** Trace point code ***/
/* Tracepoint format: /sys/kernel/debug/tracing/events/xdp/xdp_redirect/format
* Code in: kernel/include/trace/events/xdp.h
*/
struct xdp_redirect_ctx {
u64 __pad; // First 8 bytes are not accessible by bpf code
int prog_id; // offset:8; size:4; signed:1;
u32 act; // offset:12 size:4; signed:0;
int ifindex; // offset:16 size:4; signed:1;
int err; // offset:20 size:4; signed:1;
int to_ifindex; // offset:24 size:4; signed:1;
u32 map_id; // offset:28 size:4; signed:0;
int map_index; // offset:32 size:4; signed:1;
}; // offset:36
enum {
XDP_REDIRECT_SUCCESS = 0,
XDP_REDIRECT_ERROR = 1
};
static __always_inline
int xdp_redirect_collect_stat(struct xdp_redirect_ctx *ctx)
{
u32 key = XDP_REDIRECT_ERROR;
struct datarec *rec;
int err = ctx->err;
if (!err)
key = XDP_REDIRECT_SUCCESS;
rec = bpf_map_lookup_elem(&redirect_err_cnt, &key);
if (!rec)
return 0;
rec->dropped += 1;
return 0; /* Indicate event was filtered (no further processing)*/
/*
* Returning 1 here would allow e.g. a perf-record tracepoint
* to see and record these events, but it doesn't work well
* in-practice as stopping perf-record also unload this
* bpf_prog. Plus, there is additional overhead of doing so.
*/
}
SEC("tracepoint/xdp/xdp_redirect_err")
int trace_xdp_redirect_err(struct xdp_redirect_ctx *ctx)
{
return xdp_redirect_collect_stat(ctx);
}
SEC("tracepoint/xdp/xdp_redirect_map_err")
int trace_xdp_redirect_map_err(struct xdp_redirect_ctx *ctx)
{
return xdp_redirect_collect_stat(ctx);
}
/* Tracepoint format: /sys/kernel/debug/tracing/events/xdp/xdp_exception/format
* Code in: kernel/include/trace/events/xdp.h
*/
struct xdp_exception_ctx {
u64 __pad; // First 8 bytes are not accessible by bpf code
int prog_id; // offset:8; size:4; signed:1;
u32 act; // offset:12; size:4; signed:0;
int ifindex; // offset:16; size:4; signed:1;
};
SEC("tracepoint/xdp/xdp_exception")
int trace_xdp_exception(struct xdp_exception_ctx *ctx)
{
struct datarec *rec;
u32 key = 0;
rec = bpf_map_lookup_elem(&exception_cnt, &key);
if (!rec)
return 1;
rec->dropped += 1;
return 0;
}
/* Tracepoint: /sys/kernel/debug/tracing/events/xdp/xdp_cpumap_enqueue/format
* Code in: kernel/include/trace/events/xdp.h
*/
struct cpumap_enqueue_ctx {
u64 __pad; // First 8 bytes are not accessible by bpf code
int map_id; // offset:8; size:4; signed:1;
u32 act; // offset:12; size:4; signed:0;
int cpu; // offset:16; size:4; signed:1;
unsigned int drops; // offset:20; size:4; signed:0;
unsigned int processed; // offset:24; size:4; signed:0;
int to_cpu; // offset:28; size:4; signed:1;
};
SEC("tracepoint/xdp/xdp_cpumap_enqueue")
int trace_xdp_cpumap_enqueue(struct cpumap_enqueue_ctx *ctx)
{
u32 to_cpu = ctx->to_cpu;
struct datarec *rec;
if (to_cpu >= MAX_CPUS)
return 1;
rec = bpf_map_lookup_elem(&cpumap_enqueue_cnt, &to_cpu);
if (!rec)
return 0;
rec->processed += ctx->processed;
rec->dropped += ctx->drops;
/* Record bulk events, then userspace can calc average bulk size */
if (ctx->processed > 0)
rec->issue += 1;
/* Inception: It's possible to detect overload situations, via
* this tracepoint. This can be used for creating a feedback
* loop to XDP, which can take appropriate actions to mitigate
* this overload situation.
*/
return 0;
}
/* Tracepoint: /sys/kernel/debug/tracing/events/xdp/xdp_cpumap_kthread/format
* Code in: kernel/include/trace/events/xdp.h
*/
struct cpumap_kthread_ctx {
u64 __pad; // First 8 bytes are not accessible by bpf code
int map_id; // offset:8; size:4; signed:1;
u32 act; // offset:12; size:4; signed:0;
int cpu; // offset:16; size:4; signed:1;
unsigned int drops; // offset:20; size:4; signed:0;
unsigned int processed; // offset:24; size:4; signed:0;
int sched; // offset:28; size:4; signed:1;
};
SEC("tracepoint/xdp/xdp_cpumap_kthread")
int trace_xdp_cpumap_kthread(struct cpumap_kthread_ctx *ctx)
{
struct datarec *rec;
u32 key = 0;
rec = bpf_map_lookup_elem(&cpumap_kthread_cnt, &key);
if (!rec)
return 0;
rec->processed += ctx->processed;
rec->dropped += ctx->drops;
/* Count times kthread yielded CPU via schedule call */
if (ctx->sched)
rec->issue++;
return 0;
}

697
samples/bpf/xdp_redirect_cpu_user.c Normal file
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@ -0,0 +1,697 @@
/* GPLv2 Copyright(c) 2017 Jesper Dangaard Brouer, Red Hat, Inc.
*/
static const char *__doc__ =
" XDP redirect with a CPU-map type \"BPF_MAP_TYPE_CPUMAP\"";
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <unistd.h>
#include <locale.h>
#include <sys/resource.h>
#include <getopt.h>
#include <net/if.h>
#include <time.h>
#include <arpa/inet.h>
#include <linux/if_link.h>
#define MAX_CPUS 12 /* WARNING - sync with _kern.c */
/* How many xdp_progs are defined in _kern.c */
#define MAX_PROG 5
/* Wanted to get rid of bpf_load.h and fake-"libbpf.h" (and instead
* use bpf/libbpf.h), but cannot as (currently) needed for XDP
* attaching to a device via set_link_xdp_fd()
*/
#include "libbpf.h"
#include "bpf_load.h"
#include "bpf_util.h"
static int ifindex = -1;
static char ifname_buf[IF_NAMESIZE];
static char *ifname;
static __u32 xdp_flags;
/* Exit return codes */
#define EXIT_OK 0
#define EXIT_FAIL 1
#define EXIT_FAIL_OPTION 2
#define EXIT_FAIL_XDP 3
#define EXIT_FAIL_BPF 4
#define EXIT_FAIL_MEM 5
static const struct option long_options[] = {
{"help", no_argument, NULL, 'h' },
{"dev", required_argument, NULL, 'd' },
{"skb-mode", no_argument, NULL, 'S' },
{"debug", no_argument, NULL, 'D' },
{"sec", required_argument, NULL, 's' },
{"prognum", required_argument, NULL, 'p' },
{"qsize", required_argument, NULL, 'q' },
{"cpu", required_argument, NULL, 'c' },
{"stress-mode", no_argument, NULL, 'x' },
{"no-separators", no_argument, NULL, 'z' },
{0, 0, NULL, 0 }
};
static void int_exit(int sig)
{
fprintf(stderr,
"Interrupted: Removing XDP program on ifindex:%d device:%s\n",
ifindex, ifname);
if (ifindex > -1)
set_link_xdp_fd(ifindex, -1, xdp_flags);
exit(EXIT_OK);
}
static void usage(char *argv[])
{
int i;
printf("\nDOCUMENTATION:\n%s\n", __doc__);
printf("\n");
printf(" Usage: %s (options-see-below)\n", argv[0]);
printf(" Listing options:\n");
for (i = 0; long_options[i].name != 0; i++) {
printf(" --%-12s", long_options[i].name);
if (long_options[i].flag != NULL)
printf(" flag (internal value:%d)",
*long_options[i].flag);
else
printf(" short-option: -%c",
long_options[i].val);
printf("\n");
}
printf("\n");
}
/* gettime returns the current time of day in nanoseconds.
* Cost: clock_gettime (ns) => 26ns (CLOCK_MONOTONIC)
* clock_gettime (ns) => 9ns (CLOCK_MONOTONIC_COARSE)
*/
#define NANOSEC_PER_SEC 1000000000 /* 10^9 */
static __u64 gettime(void)
{
struct timespec t;
int res;
res = clock_gettime(CLOCK_MONOTONIC, &t);
if (res < 0) {
fprintf(stderr, "Error with gettimeofday! (%i)\n", res);
exit(EXIT_FAIL);
}
return (__u64) t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec;
}
/* Common stats data record shared with _kern.c */
struct datarec {
__u64 processed;
__u64 dropped;
__u64 issue;
};
struct record {
__u64 timestamp;
struct datarec total;
struct datarec *cpu;
};
struct stats_record {
struct record rx_cnt;
struct record redir_err;
struct record kthread;
struct record exception;
struct record enq[MAX_CPUS];
};
static bool map_collect_percpu(int fd, __u32 key, struct record *rec)
{
/* For percpu maps, userspace gets a value per possible CPU */
unsigned int nr_cpus = bpf_num_possible_cpus();
struct datarec values[nr_cpus];
__u64 sum_processed = 0;
__u64 sum_dropped = 0;
__u64 sum_issue = 0;
int i;
if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
fprintf(stderr,
"ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
return false;
}
/* Get time as close as possible to reading map contents */
rec->timestamp = gettime();
/* Record and sum values from each CPU */
for (i = 0; i < nr_cpus; i++) {
rec->cpu[i].processed = values[i].processed;
sum_processed += values[i].processed;
rec->cpu[i].dropped = values[i].dropped;
sum_dropped += values[i].dropped;
rec->cpu[i].issue = values[i].issue;
sum_issue += values[i].issue;
}
rec->total.processed = sum_processed;
rec->total.dropped = sum_dropped;
rec->total.issue = sum_issue;
return true;
}
static struct datarec *alloc_record_per_cpu(void)
{
unsigned int nr_cpus = bpf_num_possible_cpus();
struct datarec *array;
size_t size;
size = sizeof(struct datarec) * nr_cpus;
array = malloc(size);
memset(array, 0, size);
if (!array) {
fprintf(stderr, "Mem alloc error (nr_cpus:%u)\n", nr_cpus);
exit(EXIT_FAIL_MEM);
}
return array;
}
static struct stats_record *alloc_stats_record(void)
{
struct stats_record *rec;
int i;
rec = malloc(sizeof(*rec));
memset(rec, 0, sizeof(*rec));
if (!rec) {
fprintf(stderr, "Mem alloc error\n");
exit(EXIT_FAIL_MEM);
}
rec->rx_cnt.cpu = alloc_record_per_cpu();
rec->redir_err.cpu = alloc_record_per_cpu();
rec->kthread.cpu = alloc_record_per_cpu();
rec->exception.cpu = alloc_record_per_cpu();
for (i = 0; i < MAX_CPUS; i++)
rec->enq[i].cpu = alloc_record_per_cpu();
return rec;
}
static void free_stats_record(struct stats_record *r)
{
int i;
for (i = 0; i < MAX_CPUS; i++)
free(r->enq[i].cpu);
free(r->exception.cpu);
free(r->kthread.cpu);
free(r->redir_err.cpu);
free(r->rx_cnt.cpu);
free(r);
}
static double calc_period(struct record *r, struct record *p)
{
double period_ = 0;
__u64 period = 0;
period = r->timestamp - p->timestamp;
if (period > 0)
period_ = ((double) period / NANOSEC_PER_SEC);
return period_;
}
static __u64 calc_pps(struct datarec *r, struct datarec *p, double period_)
{
__u64 packets = 0;
__u64 pps = 0;
if (period_ > 0) {
packets = r->processed - p->processed;
pps = packets / period_;
}
return pps;
}
static __u64 calc_drop_pps(struct datarec *r, struct datarec *p, double period_)
{
__u64 packets = 0;
__u64 pps = 0;
if (period_ > 0) {
packets = r->dropped - p->dropped;
pps = packets / period_;
}
return pps;
}
static __u64 calc_errs_pps(struct datarec *r,
struct datarec *p, double period_)
{
__u64 packets = 0;
__u64 pps = 0;
if (period_ > 0) {
packets = r->issue - p->issue;
pps = packets / period_;
}
return pps;
}
static void stats_print(struct stats_record *stats_rec,
struct stats_record *stats_prev,
int prog_num)
{
unsigned int nr_cpus = bpf_num_possible_cpus();
double pps = 0, drop = 0, err = 0;
struct record *rec, *prev;
int to_cpu;
double t;
int i;
/* Header */
printf("Running XDP/eBPF prog_num:%d\n", prog_num);
printf("%-15s %-7s %-14s %-11s %-9s\n",
"XDP-cpumap", "CPU:to", "pps", "drop-pps", "extra-info");
/* XDP rx_cnt */
{
char *fmt_rx = "%-15s %-7d %'-14.0f %'-11.0f %'-10.0f %s\n";
char *fm2_rx = "%-15s %-7s %'-14.0f %'-11.0f\n";
char *errstr = "";
rec = &stats_rec->rx_cnt;
prev = &stats_prev->rx_cnt;
t = calc_period(rec, prev);
for (i = 0; i < nr_cpus; i++) {
struct datarec *r = &rec->cpu[i];
struct datarec *p = &prev->cpu[i];
pps = calc_pps(r, p, t);
drop = calc_drop_pps(r, p, t);
err = calc_errs_pps(r, p, t);
if (err > 0)
errstr = "cpu-dest/err";
if (pps > 0)
printf(fmt_rx, "XDP-RX",
i, pps, drop, err, errstr);
}
pps = calc_pps(&rec->total, &prev->total, t);
drop = calc_drop_pps(&rec->total, &prev->total, t);
err = calc_errs_pps(&rec->total, &prev->total, t);
printf(fm2_rx, "XDP-RX", "total", pps, drop);
}
/* cpumap enqueue stats */
for (to_cpu = 0; to_cpu < MAX_CPUS; to_cpu++) {
char *fmt = "%-15s %3d:%-3d %'-14.0f %'-11.0f %'-10.2f %s\n";
char *fm2 = "%-15s %3s:%-3d %'-14.0f %'-11.0f %'-10.2f %s\n";
char *errstr = "";
rec = &stats_rec->enq[to_cpu];
prev = &stats_prev->enq[to_cpu];
t = calc_period(rec, prev);
for (i = 0; i < nr_cpus; i++) {
struct datarec *r = &rec->cpu[i];
struct datarec *p = &prev->cpu[i];
pps = calc_pps(r, p, t);
drop = calc_drop_pps(r, p, t);
err = calc_errs_pps(r, p, t);
if (err > 0) {
errstr = "bulk-average";
err = pps / err; /* calc average bulk size */
}
if (pps > 0)
printf(fmt, "cpumap-enqueue",
i, to_cpu, pps, drop, err, errstr);
}
pps = calc_pps(&rec->total, &prev->total, t);
if (pps > 0) {
drop = calc_drop_pps(&rec->total, &prev->total, t);
err = calc_errs_pps(&rec->total, &prev->total, t);
if (err > 0) {
errstr = "bulk-average";
err = pps / err; /* calc average bulk size */
}
printf(fm2, "cpumap-enqueue",
"sum", to_cpu, pps, drop, err, errstr);
}
}
/* cpumap kthread stats */
{
char *fmt_k = "%-15s %-7d %'-14.0f %'-11.0f %'-10.0f %s\n";
char *fm2_k = "%-15s %-7s %'-14.0f %'-11.0f %'-10.0f %s\n";
char *e_str = "";
rec = &stats_rec->kthread;
prev = &stats_prev->kthread;
t = calc_period(rec, prev);
for (i = 0; i < nr_cpus; i++) {
struct datarec *r = &rec->cpu[i];
struct datarec *p = &prev->cpu[i];
pps = calc_pps(r, p, t);
drop = calc_drop_pps(r, p, t);
err = calc_errs_pps(r, p, t);
if (err > 0)
e_str = "sched";
if (pps > 0)
printf(fmt_k, "cpumap_kthread",
i, pps, drop, err, e_str);
}
pps = calc_pps(&rec->total, &prev->total, t);
drop = calc_drop_pps(&rec->total, &prev->total, t);
err = calc_errs_pps(&rec->total, &prev->total, t);
if (err > 0)
e_str = "sched-sum";
printf(fm2_k, "cpumap_kthread", "total", pps, drop, err, e_str);
}
/* XDP redirect err tracepoints (very unlikely) */
{
char *fmt_err = "%-15s %-7d %'-14.0f %'-11.0f\n";
char *fm2_err = "%-15s %-7s %'-14.0f %'-11.0f\n";
rec = &stats_rec->redir_err;
prev = &stats_prev->redir_err;
t = calc_period(rec, prev);
for (i = 0; i < nr_cpus; i++) {
struct datarec *r = &rec->cpu[i];
struct datarec *p = &prev->cpu[i];
pps = calc_pps(r, p, t);
drop = calc_drop_pps(r, p, t);
if (pps > 0)
printf(fmt_err, "redirect_err", i, pps, drop);
}
pps = calc_pps(&rec->total, &prev->total, t);
drop = calc_drop_pps(&rec->total, &prev->total, t);
printf(fm2_err, "redirect_err", "total", pps, drop);
}
/* XDP general exception tracepoints */
{
char *fmt_err = "%-15s %-7d %'-14.0f %'-11.0f\n";
char *fm2_err = "%-15s %-7s %'-14.0f %'-11.0f\n";
rec = &stats_rec->exception;
prev = &stats_prev->exception;
t = calc_period(rec, prev);
for (i = 0; i < nr_cpus; i++) {
struct datarec *r = &rec->cpu[i];
struct datarec *p = &prev->cpu[i];
pps = calc_pps(r, p, t);
drop = calc_drop_pps(r, p, t);
if (pps > 0)
printf(fmt_err, "xdp_exception", i, pps, drop);
}
pps = calc_pps(&rec->total, &prev->total, t);
drop = calc_drop_pps(&rec->total, &prev->total, t);
printf(fm2_err, "xdp_exception", "total", pps, drop);
}
printf("\n");
fflush(stdout);
}
static void stats_collect(struct stats_record *rec)
{
int fd, i;
fd = map_fd[1]; /* map: rx_cnt */
map_collect_percpu(fd, 0, &rec->rx_cnt);
fd = map_fd[2]; /* map: redirect_err_cnt */
map_collect_percpu(fd, 1, &rec->redir_err);
fd = map_fd[3]; /* map: cpumap_enqueue_cnt */
for (i = 0; i < MAX_CPUS; i++)
map_collect_percpu(fd, i, &rec->enq[i]);
fd = map_fd[4]; /* map: cpumap_kthread_cnt */
map_collect_percpu(fd, 0, &rec->kthread);
fd = map_fd[8]; /* map: exception_cnt */
map_collect_percpu(fd, 0, &rec->exception);
}
/* Pointer swap trick */
static inline void swap(struct stats_record **a, struct stats_record **b)
{
struct stats_record *tmp;
tmp = *a;
*a = *b;
*b = tmp;
}
static int create_cpu_entry(__u32 cpu, __u32 queue_size,
__u32 avail_idx, bool new)
{
__u32 curr_cpus_count = 0;
__u32 key = 0;
int ret;
/* Add a CPU entry to cpumap, as this allocate a cpu entry in
* the kernel for the cpu.
*/
ret = bpf_map_update_elem(map_fd[0], &cpu, &queue_size, 0);
if (ret) {
fprintf(stderr, "Create CPU entry failed (err:%d)\n", ret);
exit(EXIT_FAIL_BPF);
}
/* Inform bpf_prog's that a new CPU is available to select
* from via some control maps.
*/
/* map_fd[5] = cpus_available */
ret = bpf_map_update_elem(map_fd[5], &avail_idx, &cpu, 0);
if (ret) {
fprintf(stderr, "Add to avail CPUs failed\n");
exit(EXIT_FAIL_BPF);
}
/* When not replacing/updating existing entry, bump the count */
/* map_fd[6] = cpus_count */
ret = bpf_map_lookup_elem(map_fd[6], &key, &curr_cpus_count);
if (ret) {
fprintf(stderr, "Failed reading curr cpus_count\n");
exit(EXIT_FAIL_BPF);
}
if (new) {
curr_cpus_count++;
ret = bpf_map_update_elem(map_fd[6], &key, &curr_cpus_count, 0);
if (ret) {
fprintf(stderr, "Failed write curr cpus_count\n");
exit(EXIT_FAIL_BPF);
}
}
/* map_fd[7] = cpus_iterator */
printf("%s CPU:%u as idx:%u queue_size:%d (total cpus_count:%u)\n",
new ? "Add-new":"Replace", cpu, avail_idx,
queue_size, curr_cpus_count);
return 0;
}
/* CPUs are zero-indexed. Thus, add a special sentinel default value
* in map cpus_available to mark CPU index'es not configured
*/
static void mark_cpus_unavailable(void)
{
__u32 invalid_cpu = MAX_CPUS;
int ret, i;
for (i = 0; i < MAX_CPUS; i++) {
/* map_fd[5] = cpus_available */
ret = bpf_map_update_elem(map_fd[5], &i, &invalid_cpu, 0);
if (ret) {
fprintf(stderr, "Failed marking CPU unavailable\n");
exit(EXIT_FAIL_BPF);
}
}
}
/* Stress cpumap management code by concurrently changing underlying cpumap */
static void stress_cpumap(void)
{
/* Changing qsize will cause kernel to free and alloc a new
* bpf_cpu_map_entry, with an associated/complicated tear-down
* procedure.
*/
create_cpu_entry(1, 1024, 0, false);
create_cpu_entry(1, 128, 0, false);
create_cpu_entry(1, 16000, 0, false);
}
static void stats_poll(int interval, bool use_separators, int prog_num,
bool stress_mode)
{
struct stats_record *record, *prev;
record = alloc_stats_record();
prev = alloc_stats_record();
stats_collect(record);
/* Trick to pretty printf with thousands separators use %' */
if (use_separators)
setlocale(LC_NUMERIC, "en_US");
while (1) {
swap(&prev, &record);
stats_collect(record);
stats_print(record, prev, prog_num);
sleep(interval);
if (stress_mode)
stress_cpumap();
}
free_stats_record(record);
free_stats_record(prev);
}
int main(int argc, char **argv)
{
struct rlimit r = {10 * 1024 * 1024, RLIM_INFINITY};
bool use_separators = true;
bool stress_mode = false;
char filename[256];
bool debug = false;
int added_cpus = 0;
int longindex = 0;
int interval = 2;
int prog_num = 0;
int add_cpu = -1;
__u32 qsize;
int opt;
/* Notice: choosing he queue size is very important with the
* ixgbe driver, because it's driver page recycling trick is
* dependend on pages being returned quickly. The number of
* out-standing packets in the system must be less-than 2x
* RX-ring size.
*/
qsize = 128+64;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
if (setrlimit(RLIMIT_MEMLOCK, &r)) {
perror("setrlimit(RLIMIT_MEMLOCK)");
return 1;
}
if (load_bpf_file(filename)) {
fprintf(stderr, "ERR in load_bpf_file(): %s", bpf_log_buf);
return EXIT_FAIL;
}
if (!prog_fd[0]) {
fprintf(stderr, "ERR: load_bpf_file: %s\n", strerror(errno));
return EXIT_FAIL;
}
mark_cpus_unavailable();
/* Parse commands line args */
while ((opt = getopt_long(argc, argv, "hSd:",
long_options, &longindex)) != -1) {
switch (opt) {
case 'd':
if (strlen(optarg) >= IF_NAMESIZE) {
fprintf(stderr, "ERR: --dev name too long\n");
goto error;
}
ifname = (char *)&ifname_buf;
strncpy(ifname, optarg, IF_NAMESIZE);
ifindex = if_nametoindex(ifname);
if (ifindex == 0) {
fprintf(stderr,
"ERR: --dev name unknown err(%d):%s\n",
errno, strerror(errno));
goto error;
}
break;
case 's':
interval = atoi(optarg);
break;
case 'S':
xdp_flags |= XDP_FLAGS_SKB_MODE;
break;
case 'D':
debug = true;
break;
case 'x':
stress_mode = true;
break;
case 'z':
use_separators = false;
break;
case 'p':
/* Selecting eBPF prog to load */
prog_num = atoi(optarg);
if (prog_num < 0 || prog_num >= MAX_PROG) {
fprintf(stderr,
"--prognum too large err(%d):%s\n",
errno, strerror(errno));
goto error;
}
break;
case 'c':
/* Add multiple CPUs */
add_cpu = strtoul(optarg, NULL, 0);
if (add_cpu >= MAX_CPUS) {
fprintf(stderr,
"--cpu nr too large for cpumap err(%d):%s\n",
errno, strerror(errno));
goto error;
}
create_cpu_entry(add_cpu, qsize, added_cpus, true);
added_cpus++;
break;
case 'q':
qsize = atoi(optarg);
break;
case 'h':
error:
default:
usage(argv);
return EXIT_FAIL_OPTION;
}
}
/* Required option */
if (ifindex == -1) {
fprintf(stderr, "ERR: required option --dev missing\n");
usage(argv);
return EXIT_FAIL_OPTION;
}
/* Required option */
if (add_cpu == -1) {
fprintf(stderr, "ERR: required option --cpu missing\n");
fprintf(stderr, " Specify multiple --cpu option to add more\n");
usage(argv);
return EXIT_FAIL_OPTION;
}
/* Remove XDP program when program is interrupted */
signal(SIGINT, int_exit);
if (set_link_xdp_fd(ifindex, prog_fd[prog_num], xdp_flags) < 0) {
fprintf(stderr, "link set xdp fd failed\n");
return EXIT_FAIL_XDP;
}
if (debug) {
printf("Debug-mode reading trace pipe (fix #define DEBUG)\n");
read_trace_pipe();
}
stats_poll(interval, use_separators, prog_num, stress_mode);
return EXIT_OK;
}