diff options
author | Kumar Kartikeya Dwivedi | 2021-08-21 05:50:05 +0530 |
---|---|---|
committer | Alexei Starovoitov | 2021-08-24 14:48:42 -0700 |
commit | 79ccf4529ee67510fdad8ecdfcf37528d353a36c (patch) | |
tree | 5dbdf81efb89cfcb98c60c2deef168b5abcdc86d /samples | |
parent | b926c55d856cbe2593c44e783b31e2cdb0ef6371 (diff) |
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
Diffstat (limited to 'samples')
-rw-r--r-- | samples/bpf/Makefile | 5 | ||||
-rw-r--r-- | samples/bpf/xdp_redirect_cpu.bpf.c (renamed from samples/bpf/xdp_redirect_cpu_kern.c) | 393 |
2 files changed, 105 insertions, 293 deletions
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index d05105227ec5..231cdbc773a7 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -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 diff --git a/samples/bpf/xdp_redirect_cpu_kern.c b/samples/bpf/xdp_redirect_cpu.bpf.c index 8255025dea97..f10fe3cf25f6 100644 --- a/samples/bpf/xdp_redirect_cpu_kern.c +++ b/samples/bpf/xdp_redirect_cpu.bpf.c @@ -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); @@ -92,24 +37,16 @@ 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"); -/* Helper parse functions */ +char tx_mac_addr[ETH_ALEN]; -/* 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; -}; +/* Helper parse functions */ static __always_inline bool parse_eth(struct ethhdr *eth, void *data_end, @@ -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, ð_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, ð_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); } -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) +SEC("xdp_cpumap/redirect") +int xdp_redirect_cpu_devmap(struct xdp_md *ctx) { - u32 key = XDP_REDIRECT_ERROR; - struct datarec *rec; - int err = ctx->err; + void *data_end = (void *)(long)ctx->data_end; + void *data = (void *)(long)ctx->data; + struct ethhdr *eth = data; + u64 nh_off; - if (!err) - key = XDP_REDIRECT_SUCCESS; + nh_off = sizeof(*eth); + if (data + nh_off > data_end) + return XDP_DROP; - 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. - */ + swap_src_dst_mac(data); + return bpf_redirect_map(&tx_port, 0, 0); } -SEC("tracepoint/xdp/xdp_redirect_err") -int trace_xdp_redirect_err(struct xdp_redirect_ctx *ctx) +SEC("xdp_cpumap/pass") +int xdp_redirect_cpu_pass(struct xdp_md *ctx) { - return xdp_redirect_collect_stat(ctx); + return XDP_PASS; } -SEC("tracepoint/xdp/xdp_redirect_map_err") -int trace_xdp_redirect_map_err(struct xdp_redirect_ctx *ctx) +SEC("xdp_cpumap/drop") +int xdp_redirect_cpu_drop(struct xdp_md *ctx) { - return xdp_redirect_collect_stat(ctx); + return XDP_DROP; } -/* 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) +SEC("xdp_devmap/egress") +int xdp_redirect_egress_prog(struct xdp_md *ctx) { - struct datarec *rec; - u32 key = 0; - - rec = bpf_map_lookup_elem(&exception_cnt, &key); - if (!rec) - return 1; - rec->dropped += 1; - - return 0; -} + void *data_end = (void *)(long)ctx->data_end; + void *data = (void *)(long)ctx->data; + struct ethhdr *eth = data; + u64 nh_off; -/* 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; + nh_off = sizeof(*eth); + if (data + nh_off > data_end) + return XDP_DROP; - if (to_cpu >= MAX_CPUS) - return 1; + __builtin_memcpy(eth->h_source, (const char *)tx_mac_addr, ETH_ALEN); - 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; + return XDP_PASS; } -/* 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; -} +char _license[] SEC("license") = "GPL"; |