diff options
| -rw-r--r-- | samples/bpf/tracex3.bpf.c | 36 |
1 files changed, 24 insertions, 12 deletions
diff --git a/samples/bpf/tracex3.bpf.c b/samples/bpf/tracex3.bpf.c index 7cc60f10d2e5..41f37966f5f5 100644 --- a/samples/bpf/tracex3.bpf.c +++ b/samples/bpf/tracex3.bpf.c @@ -9,6 +9,12 @@ #include <bpf/bpf_helpers.h> #include <bpf/bpf_tracing.h> +struct start_key { + dev_t dev; + u32 _pad; + sector_t sector; +}; + struct { __uint(type, BPF_MAP_TYPE_HASH); __type(key, long); @@ -16,16 +22,17 @@ struct { __uint(max_entries, 4096); } my_map SEC(".maps"); -/* kprobe is NOT a stable ABI. If kernel internals change this bpf+kprobe - * example will no longer be meaningful - */ -SEC("kprobe/blk_mq_start_request") -int bpf_prog1(struct pt_regs *ctx) +/* from /sys/kernel/tracing/events/block/block_io_start/format */ +SEC("tracepoint/block/block_io_start") +int bpf_prog1(struct trace_event_raw_block_rq *ctx) { - long rq = PT_REGS_PARM1(ctx); u64 val = bpf_ktime_get_ns(); + struct start_key key = { + .dev = ctx->dev, + .sector = ctx->sector + }; - bpf_map_update_elem(&my_map, &rq, &val, BPF_ANY); + bpf_map_update_elem(&my_map, &key, &val, BPF_ANY); return 0; } @@ -47,21 +54,26 @@ struct { __uint(max_entries, SLOTS); } lat_map SEC(".maps"); -SEC("kprobe/__blk_account_io_done") -int bpf_prog2(struct pt_regs *ctx) +/* from /sys/kernel/tracing/events/block/block_io_done/format */ +SEC("tracepoint/block/block_io_done") +int bpf_prog2(struct trace_event_raw_block_rq *ctx) { - long rq = PT_REGS_PARM1(ctx); + struct start_key key = { + .dev = ctx->dev, + .sector = ctx->sector + }; + u64 *value, l, base; u32 index; - value = bpf_map_lookup_elem(&my_map, &rq); + value = bpf_map_lookup_elem(&my_map, &key); if (!value) return 0; u64 cur_time = bpf_ktime_get_ns(); u64 delta = cur_time - *value; - bpf_map_delete_elem(&my_map, &rq); + bpf_map_delete_elem(&my_map, &key); /* the lines below are computing index = log10(delta)*10 * using integer arithmetic |