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samples: bpf: Convert xdp_redirect_cpu_kern.o to XDP samples helper 

Similar to xdp_monitor_kern, a lot of these BPF programs have been
reimplemented properly consolidating missing features from other XDP
samples. Hence, drop the unneeded code and rename to .bpf.c suffix.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210821002010.845777-18-memxor@gmail.com
This commit is contained in:
Kumar Kartikeya Dwivedi 2021-08-21 05:50:05 +05:30 коммит произвёл Alexei Starovoitov
Родитель b926c55d85
Коммит 79ccf4529e
2 изменённых файлов: 121 добавлений и 309 удалений
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5
samples/bpf/Makefile
Просмотреть файл

@ -165,7 +165,6 @@ always-y += tcp_tos_reflect_kern.o
always-y += tcp_dumpstats_kern.o
always-y += xdp_redirect_map_kern.o
always-y += xdp_redirect_map_multi_kern.o
always-y += xdp_redirect_cpu_kern.o
always-y += xdp_rxq_info_kern.o
always-y += xdp2skb_meta_kern.o
always-y += syscall_tp_kern.o
@ -356,6 +355,7 @@ endef
CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
$(obj)/xdp_redirect_cpu.bpf.o: $(obj)/xdp_sample.bpf.o
$(obj)/xdp_redirect.bpf.o: $(obj)/xdp_sample.bpf.o
$(obj)/xdp_monitor.bpf.o: $(obj)/xdp_sample.bpf.o
@ -367,9 +367,10 @@ $(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/x
-I$(srctree)/tools/lib $(CLANG_SYS_INCLUDES) \
-c $(filter %.bpf.c,$^) -o $@
LINKED_SKELS := xdp_redirect.skel.h xdp_monitor.skel.h
LINKED_SKELS := xdp_redirect_cpu.skel.h xdp_redirect.skel.h xdp_monitor.skel.h
clean-files += $(LINKED_SKELS)
xdp_redirect_cpu.skel.h-deps := xdp_redirect_cpu.bpf.o xdp_sample.bpf.o
xdp_redirect.skel.h-deps := xdp_redirect.bpf.o xdp_sample.bpf.o
xdp_monitor.skel.h-deps := xdp_monitor.bpf.o xdp_sample.bpf.o

425
samples/bpf/xdp_redirect_cpu_kern.c → samples/bpf/xdp_redirect_cpu.bpf.c
Просмотреть файл

@ -2,74 +2,18 @@
*
* 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/bpf_helpers.h>
#include "vmlinux.h"
#include "xdp_sample.bpf.h"
#include "xdp_sample_shared.h"
#include "hash_func01.h"
#define MAX_CPUS NR_CPUS
/* Special map type that can XDP_REDIRECT frames to another CPU */
struct {
__uint(type, BPF_MAP_TYPE_CPUMAP);
__uint(key_size, sizeof(u32));
__uint(value_size, sizeof(struct bpf_cpumap_val));
__uint(max_entries, MAX_CPUS);
} cpu_map SEC(".maps");
/* Common stats data record to keep userspace more simple */
struct datarec {
__u64 processed;
__u64 dropped;
__u64 issue;
__u64 xdp_pass;
__u64 xdp_drop;
__u64 xdp_redirect;
};
/* Count RX packets, as XDP bpf_prog doesn't get direct TX-success
* feedback. Redirect TX errors can be caught via a tracepoint.
*/
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
__type(key, u32);
__type(value, struct datarec);
__uint(max_entries, 1);
} rx_cnt SEC(".maps");
/* Used by trace point */
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
__type(key, u32);
__type(value, struct datarec);
__uint(max_entries, 2);
/* TODO: have entries for all possible errno's */
} redirect_err_cnt SEC(".maps");
/* Used by trace point */
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
__type(key, u32);
__type(value, struct datarec);
__uint(max_entries, MAX_CPUS);
} cpumap_enqueue_cnt SEC(".maps");
/* Used by trace point */
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
__type(key, u32);
__type(value, struct datarec);
__uint(max_entries, 1);
} cpumap_kthread_cnt SEC(".maps");
/* Set of maps controlling available CPU, and for iterating through
* selectable redirect CPUs.
*/
@ -77,14 +21,15 @@ struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__type(key, u32);
__type(value, u32);
__uint(max_entries, MAX_CPUS);
} cpus_available SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__type(key, u32);
__type(value, u32);
__uint(max_entries, 1);
} cpus_count SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
__type(key, u32);
@ -92,25 +37,17 @@ struct {
__uint(max_entries, 1);
} cpus_iterator SEC(".maps");
/* Used by trace point */
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
__type(key, u32);
__type(value, struct datarec);
__uint(type, BPF_MAP_TYPE_DEVMAP);
__uint(key_size, sizeof(int));
__uint(value_size, sizeof(struct bpf_devmap_val));
__uint(max_entries, 1);
} exception_cnt SEC(".maps");
} tx_port SEC(".maps");
char tx_mac_addr[ETH_ALEN];
/* 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)
@ -125,11 +62,12 @@ bool parse_eth(struct ethhdr *eth, void *data_end,
eth_type = eth->h_proto;
/* Skip non 802.3 Ethertypes */
if (unlikely(ntohs(eth_type) < ETH_P_802_3_MIN))
if (__builtin_expect(bpf_ntohs(eth_type) < ETH_P_802_3_MIN, 0))
return false;
/* Handle VLAN tagged packet */
if (eth_type == htons(ETH_P_8021Q) || eth_type == htons(ETH_P_8021AD)) {
if (eth_type == bpf_htons(ETH_P_8021Q) ||
eth_type == bpf_htons(ETH_P_8021AD)) {
struct vlan_hdr *vlan_hdr;
vlan_hdr = (void *)eth + offset;
@ -139,7 +77,8 @@ bool parse_eth(struct ethhdr *eth, void *data_end,
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)) {
if (eth_type == bpf_htons(ETH_P_8021Q) ||
eth_type == bpf_htons(ETH_P_8021AD)) {
struct vlan_hdr *vlan_hdr;
vlan_hdr = (void *)eth + offset;
@ -149,7 +88,7 @@ bool parse_eth(struct ethhdr *eth, void *data_end,
eth_type = vlan_hdr->h_vlan_encapsulated_proto;
}
*eth_proto = ntohs(eth_type);
*eth_proto = bpf_ntohs(eth_type);
*l3_offset = offset;
return true;
}
@ -172,7 +111,7 @@ u16 get_dest_port_ipv4_udp(struct xdp_md *ctx, u64 nh_off)
if (udph + 1 > data_end)
return 0;
dport = ntohs(udph->dest);
dport = bpf_ntohs(udph->dest);
return dport;
}
@ -200,50 +139,48 @@ int get_proto_ipv6(struct xdp_md *ctx, u64 nh_off)
return ip6h->nexthdr;
}
SEC("xdp_cpu_map0")
SEC("xdp")
int xdp_prognum0_no_touch(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
u32 key = bpf_get_smp_processor_id();
struct datarec *rec;
u32 *cpu_selected;
u32 cpu_dest;
u32 key = 0;
u32 cpu_dest = 0;
u32 key0 = 0;
/* Only use first entry in cpus_available */
cpu_selected = bpf_map_lookup_elem(&cpus_available, &key);
cpu_selected = bpf_map_lookup_elem(&cpus_available, &key0);
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++;
return XDP_PASS;
NO_TEAR_INC(rec->processed);
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
if (cpu_dest >= nr_cpus) {
NO_TEAR_INC(rec->issue);
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
SEC("xdp_cpu_map1_touch_data")
SEC("xdp")
int xdp_prognum1_touch_data(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
u32 key = bpf_get_smp_processor_id();
struct ethhdr *eth = data;
struct datarec *rec;
u32 *cpu_selected;
u32 cpu_dest;
u32 cpu_dest = 0;
u32 key0 = 0;
u16 eth_type;
u32 key = 0;
/* Only use first entry in cpus_available */
cpu_selected = bpf_map_lookup_elem(&cpus_available, &key);
cpu_selected = bpf_map_lookup_elem(&cpus_available, &key0);
if (!cpu_selected)
return XDP_ABORTED;
cpu_dest = *cpu_selected;
@ -252,36 +189,33 @@ int xdp_prognum1_touch_data(struct xdp_md *ctx)
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++;
return XDP_PASS;
NO_TEAR_INC(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++;
if (bpf_ntohs(eth_type) < ETH_P_802_3_MIN) {
NO_TEAR_INC(rec->dropped);
return XDP_DROP;
}
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
if (cpu_dest >= nr_cpus) {
NO_TEAR_INC(rec->issue);
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
SEC("xdp_cpu_map2_round_robin")
SEC("xdp")
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;
u32 key = bpf_get_smp_processor_id();
struct datarec *rec;
u32 cpu_dest;
u32 *cpu_lookup;
u32 cpu_dest = 0;
u32 key0 = 0;
u32 *cpu_selected;
@ -307,40 +241,37 @@ int xdp_prognum2_round_robin(struct xdp_md *ctx)
return XDP_ABORTED;
cpu_dest = *cpu_selected;
/* Count RX packet in map */
rec = bpf_map_lookup_elem(&rx_cnt, &key0);
rec = bpf_map_lookup_elem(&rx_cnt, &key);
if (!rec)
return XDP_ABORTED;
rec->processed++;
return XDP_PASS;
NO_TEAR_INC(rec->processed);
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
if (cpu_dest >= nr_cpus) {
NO_TEAR_INC(rec->issue);
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
SEC("xdp_cpu_map3_proto_separate")
SEC("xdp")
int xdp_prognum3_proto_separate(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
u32 key = bpf_get_smp_processor_id();
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;
u32 cpu_idx = 0;
/* Count RX packet in map */
rec = bpf_map_lookup_elem(&rx_cnt, &key);
if (!rec)
return XDP_ABORTED;
rec->processed++;
return XDP_PASS;
NO_TEAR_INC(rec->processed);
if (!(parse_eth(eth, data_end, &eth_proto, &l3_offset)))
return XDP_PASS; /* Just skip */
@ -381,35 +312,33 @@ int xdp_prognum3_proto_separate(struct xdp_md *ctx)
return XDP_ABORTED;
cpu_dest = *cpu_lookup;
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
if (cpu_dest >= nr_cpus) {
NO_TEAR_INC(rec->issue);
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
SEC("xdp_cpu_map4_ddos_filter_pktgen")
SEC("xdp")
int xdp_prognum4_ddos_filter_pktgen(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
u32 key = bpf_get_smp_processor_id();
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_lookup;
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++;
return XDP_PASS;
NO_TEAR_INC(rec->processed);
if (!(parse_eth(eth, data_end, &eth_proto, &l3_offset)))
return XDP_PASS; /* Just skip */
@ -443,8 +372,7 @@ int xdp_prognum4_ddos_filter_pktgen(struct xdp_md *ctx)
/* DDoS filter UDP port 9 (pktgen) */
dest_port = get_dest_port_ipv4_udp(ctx, l3_offset);
if (dest_port == 9) {
if (rec)
rec->dropped++;
NO_TEAR_INC(rec->dropped);
return XDP_DROP;
}
break;
@ -457,11 +385,10 @@ int xdp_prognum4_ddos_filter_pktgen(struct xdp_md *ctx)
return XDP_ABORTED;
cpu_dest = *cpu_lookup;
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
if (cpu_dest >= nr_cpus) {
NO_TEAR_INC(rec->issue);
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
@ -496,10 +423,10 @@ u32 get_ipv6_hash_ip_pair(struct xdp_md *ctx, u64 nh_off)
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 = ip6h->saddr.in6_u.u6_addr32[0] + ip6h->daddr.in6_u.u6_addr32[0];
cpu_hash += ip6h->saddr.in6_u.u6_addr32[1] + ip6h->daddr.in6_u.u6_addr32[1];
cpu_hash += ip6h->saddr.in6_u.u6_addr32[2] + ip6h->daddr.in6_u.u6_addr32[2];
cpu_hash += ip6h->saddr.in6_u.u6_addr32[3] + ip6h->daddr.in6_u.u6_addr32[3];
cpu_hash = SuperFastHash((char *)&cpu_hash, 4, INITVAL + ip6h->nexthdr);
return cpu_hash;
@ -509,30 +436,29 @@ u32 get_ipv6_hash_ip_pair(struct xdp_md *ctx, u64 nh_off)
* hashing scheme is symmetric, meaning swapping IP src/dest still hit
* same CPU.
*/
SEC("xdp_cpu_map5_lb_hash_ip_pairs")
SEC("xdp")
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;
u32 key = bpf_get_smp_processor_id();
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 key0 = 0;
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++;
return XDP_PASS;
NO_TEAR_INC(rec->processed);
cpu_max = bpf_map_lookup_elem(&cpus_count, &key);
cpu_max = bpf_map_lookup_elem(&cpus_count, &key0);
if (!cpu_max)
return XDP_ABORTED;
@ -560,171 +486,56 @@ int xdp_prognum5_lb_hash_ip_pairs(struct xdp_md *ctx)
return XDP_ABORTED;
cpu_dest = *cpu_lookup;
if (cpu_dest >= MAX_CPUS) {
rec->issue++;
if (cpu_dest >= nr_cpus) {
NO_TEAR_INC(rec->issue);
return XDP_ABORTED;
}
return bpf_redirect_map(&cpu_map, cpu_dest, 0);
}
SEC("xdp_cpumap/redirect")
int xdp_redirect_cpu_devmap(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct ethhdr *eth = data;
u64 nh_off;
nh_off = sizeof(*eth);
if (data + nh_off > data_end)
return XDP_DROP;
swap_src_dst_mac(data);
return bpf_redirect_map(&tx_port, 0, 0);
}
SEC("xdp_cpumap/pass")
int xdp_redirect_cpu_pass(struct xdp_md *ctx)
{
return XDP_PASS;
}
SEC("xdp_cpumap/drop")
int xdp_redirect_cpu_drop(struct xdp_md *ctx)
{
return XDP_DROP;
}
SEC("xdp_devmap/egress")
int xdp_redirect_egress_prog(struct xdp_md *ctx)
{
void *data_end = (void *)(long)ctx->data_end;
void *data = (void *)(long)ctx->data;
struct ethhdr *eth = data;
u64 nh_off;
nh_off = sizeof(*eth);
if (data + nh_off > data_end)
return XDP_DROP;
__builtin_memcpy(eth->h_source, (const char *)tx_mac_addr, ETH_ALEN);
return XDP_PASS;
}
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
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;
unsigned int xdp_pass; // offset:32; size:4; signed:0;
unsigned int xdp_drop; // offset:36; size:4; signed:0;
unsigned int xdp_redirect; // offset:40; size:4; signed:0;
};
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;
rec->xdp_pass += ctx->xdp_pass;
rec->xdp_drop += ctx->xdp_drop;
rec->xdp_redirect += ctx->xdp_redirect;
/* Count times kthread yielded CPU via schedule call */
if (ctx->sched)
rec->issue++;
return 0;
}