mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-05 18:39:59 +00:00
![David S. Miller](/assets/img/avatar_default.png)
Daniel Borkmann says: ==================== pull-request: bpf-next 2018-08-13 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Add driver XDP support for veth. This can be used in conjunction with redirect of another XDP program e.g. sitting on NIC so the xdp_frame can be forwarded to the peer veth directly without modification, from Toshiaki. 2) Add a new BPF map type REUSEPORT_SOCKARRAY and prog type SK_REUSEPORT in order to provide more control and visibility on where a SO_REUSEPORT sk should be located, and the latter enables to directly select a sk from the bpf map. This also enables map-in-map for application migration use cases, from Martin. 3) Add a new BPF helper bpf_skb_ancestor_cgroup_id() that returns the id of cgroup v2 that is the ancestor of the cgroup associated with the skb at the ancestor_level, from Andrey. 4) Implement BPF fs map pretty-print support based on BTF data for regular hash table and LRU map, from Yonghong. 5) Decouple the ability to attach BTF for a map from the key and value pretty-printer in BPF fs, and enable further support of BTF for maps for percpu and LPM trie, from Daniel. 6) Implement a better BPF sample of using XDP's CPU redirect feature for load balancing SKB processing to remote CPU. The sample implements the same XDP load balancing as Suricata does which is symmetric hash based on IP and L4 protocol, from Jesper. 7) Revert adding NULL pointer check with WARN_ON_ONCE() in __xdp_return()'s critical path as it is ensured that the allocator is present, from Björn. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
721 lines
17 KiB
C
721 lines
17 KiB
C
/* 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"
|
|
#include "hash_func01.h"
|
|
|
|
#define MAX_CPUS 64 /* 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;
|
|
}
|
|
/* Handle double 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;
|
|
}
|
|
|
|
*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, ð_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, ð_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);
|
|
}
|
|
|
|
/* Hashing initval */
|
|
#define INITVAL 15485863
|
|
|
|
static __always_inline
|
|
u32 get_ipv4_hash_ip_pair(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;
|
|
u32 cpu_hash;
|
|
|
|
if (iph + 1 > data_end)
|
|
return 0;
|
|
|
|
cpu_hash = iph->saddr + iph->daddr;
|
|
cpu_hash = SuperFastHash((char *)&cpu_hash, 4, INITVAL + iph->protocol);
|
|
|
|
return cpu_hash;
|
|
}
|
|
|
|
static __always_inline
|
|
u32 get_ipv6_hash_ip_pair(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;
|
|
u32 cpu_hash;
|
|
|
|
if (ip6h + 1 > data_end)
|
|
return 0;
|
|
|
|
cpu_hash = ip6h->saddr.s6_addr32[0] + ip6h->daddr.s6_addr32[0];
|
|
cpu_hash += ip6h->saddr.s6_addr32[1] + ip6h->daddr.s6_addr32[1];
|
|
cpu_hash += ip6h->saddr.s6_addr32[2] + ip6h->daddr.s6_addr32[2];
|
|
cpu_hash += ip6h->saddr.s6_addr32[3] + ip6h->daddr.s6_addr32[3];
|
|
cpu_hash = SuperFastHash((char *)&cpu_hash, 4, INITVAL + ip6h->nexthdr);
|
|
|
|
return cpu_hash;
|
|
}
|
|
|
|
/* Load-Balance traffic based on hashing IP-addrs + L4-proto. The
|
|
* hashing scheme is symmetric, meaning swapping IP src/dest still hit
|
|
* same CPU.
|
|
*/
|
|
SEC("xdp_cpu_map5_lb_hash_ip_pairs")
|
|
int xdp_prognum5_lb_hash_ip_pairs(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 *cpu_max;
|
|
u32 cpu_hash;
|
|
u32 key = 0;
|
|
|
|
/* Count RX packet in map */
|
|
rec = bpf_map_lookup_elem(&rx_cnt, &key);
|
|
if (!rec)
|
|
return XDP_ABORTED;
|
|
rec->processed++;
|
|
|
|
cpu_max = bpf_map_lookup_elem(&cpus_count, &key);
|
|
if (!cpu_max)
|
|
return XDP_ABORTED;
|
|
|
|
if (!(parse_eth(eth, data_end, ð_proto, &l3_offset)))
|
|
return XDP_PASS; /* Just skip */
|
|
|
|
/* Hash for IPv4 and IPv6 */
|
|
switch (eth_proto) {
|
|
case ETH_P_IP:
|
|
cpu_hash = get_ipv4_hash_ip_pair(ctx, l3_offset);
|
|
break;
|
|
case ETH_P_IPV6:
|
|
cpu_hash = get_ipv6_hash_ip_pair(ctx, l3_offset);
|
|
break;
|
|
case ETH_P_ARP: /* ARP packet handled on CPU idx 0 */
|
|
default:
|
|
cpu_hash = 0;
|
|
}
|
|
|
|
/* Choose CPU based on hash */
|
|
cpu_idx = cpu_hash % *cpu_max;
|
|
|
|
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;
|
|
}
|