| // SPDX-License-Identifier: GPL-2.0 |
| // Copyright (c) 2020 Wenbo Zhang |
| #include <vmlinux.h> |
| #include <bpf/bpf_helpers.h> |
| #include <bpf/bpf_tracing.h> |
| #include "llcstat.h" |
| |
| #define MAX_ENTRIES 10240 |
| |
| struct { |
| __uint(type, BPF_MAP_TYPE_HASH); |
| __uint(max_entries, MAX_ENTRIES); |
| __type(key, u64); |
| __type(value, struct info); |
| } infos SEC(".maps"); |
| |
| static __always_inline |
| int trace_event(__u64 sample_period, bool miss) |
| { |
| u64 pid = bpf_get_current_pid_tgid(); |
| u32 cpu = bpf_get_smp_processor_id(); |
| struct info *infop, info = {}; |
| u64 key = pid << 32 | cpu; |
| |
| infop = bpf_map_lookup_elem(&infos, &key); |
| if (!infop) { |
| bpf_get_current_comm(info.comm, sizeof(info.comm)); |
| infop = &info; |
| } |
| if (miss) |
| infop->miss += sample_period; |
| else |
| infop->ref += sample_period; |
| if (infop == &info) |
| bpf_map_update_elem(&infos, &key, infop, 0); |
| return 0; |
| } |
| |
| SEC("perf_event") |
| int on_cache_miss(struct bpf_perf_event_data *ctx) |
| { |
| return trace_event(ctx->sample_period, true); |
| } |
| |
| SEC("perf_event") |
| int on_cache_ref(struct bpf_perf_event_data *ctx) |
| { |
| return trace_event(ctx->sample_period, false); |
| } |
| |
| char LICENSE[] SEC("license") = "GPL"; |