tcpconnlat: Remove unnecessary bpf_probe_reads

tools/tcpconnlat.py

@@ -93,14 +93,14 @@
 // are fast path and processed elsewhere, and leftovers are processed by
 // tcp_rcv_state_process(). We can trace this for handshake completion.
 // This should all be switched to static tracepoints when available.
-int trace_tcp_rcv_state_process(struct pt_regs *ctx, struct sock *sk)
+int trace_tcp_rcv_state_process(struct pt_regs *ctx, struct sock *skp)
 {
  // will be in TCP_SYN_SENT for handshake
- if (sk->__sk_common.skc_state != TCP_SYN_SENT)
+ if (skp->__sk_common.skc_state != TCP_SYN_SENT)
  return 0;
 
  // check start and calculate delta
- struct info_t *infop = start.lookup(&sk);
+ struct info_t *infop = start.lookup(&skp);
  if (infop == 0) {
  return 0; // missed entry or filtered
  }
@@ -109,19 +109,15 @@
 
  // pull in details
  u16 family = 0, dport = 0;
- struct sock *skp = NULL;
- bpf_probe_read(&skp, sizeof(skp), &sk);
- bpf_probe_read(&family, sizeof(family), &skp->__sk_common.skc_family);
- bpf_probe_read(&dport, sizeof(dport), &skp->__sk_common.skc_dport);
+ family = skp->__sk_common.skc_family;
+ dport = skp->__sk_common.skc_dport;
 
  // emit to appropriate data path
  if (family == AF_INET) {
  struct ipv4_data_t data4 = {.pid = infop->pid, .ip = 4};
  data4.ts_us = now / 1000;
- bpf_probe_read(&data4.saddr, sizeof(u32),
- &skp->__sk_common.skc_rcv_saddr);
- bpf_probe_read(&data4.daddr, sizeof(u32),
- &skp->__sk_common.skc_daddr);
+ data4.saddr = skp->__sk_common.skc_rcv_saddr;
+ data4.daddr = skp->__sk_common.skc_daddr;
  data4.dport = ntohs(dport);
  data4.delta_us = (now - ts) / 1000;
  __builtin_memcpy(&data4.task, infop->task, sizeof(data4.task));
@@ -131,16 +127,16 @@
  struct ipv6_data_t data6 = {.pid = infop->pid, .ip = 6};
  data6.ts_us = now / 1000;
  bpf_probe_read(&data6.saddr, sizeof(data6.saddr),
- &skp->__sk_common.skc_v6_rcv_saddr.in6_u.u6_addr32);
+ skp->__sk_common.skc_v6_rcv_saddr.in6_u.u6_addr32);
  bpf_probe_read(&data6.daddr, sizeof(data6.daddr),
- &skp->__sk_common.skc_v6_daddr.in6_u.u6_addr32);
+ skp->__sk_common.skc_v6_daddr.in6_u.u6_addr32);
  data6.dport = ntohs(dport);
  data6.delta_us = (now - ts) / 1000;
  __builtin_memcpy(&data6.task, infop->task, sizeof(data6.task));
  ipv6_events.perf_submit(ctx, &data6, sizeof(data6));
  }
 
- start.delete(&sk);
+ start.delete(&skp);
 
  return 0;
 }