Merge pull request #1303 from pchaigno/remove-bpf_probe_reads

Remove unnecessary bpf_probe_reads

tools/solisten.py

@@ -69,7 +69,7 @@ int kprobe__inet_listen(struct pt_regs *ctx, struct socket *sock, int backlog)
 {
         // cast types. Intermediate cast not needed, kept for readability
         struct sock *sk = sock->sk;
-        struct inet_sock *inet = inet_sk(sk);
+        struct inet_sock *inet = (struct inet_sock *)sk;
 
         // Built event for userland
         struct listen_evt_t evt = {
@@ -91,7 +91,7 @@ int kprobe__inet_listen(struct pt_regs *ctx, struct socket *sock, int backlog)
         ##FILTER_PID##
 
         // Get port
-        bpf_probe_read(&evt.lport, sizeof(u16), &(inet->inet_sport));
+        evt.lport = inet->inet_sport;
         evt.lport = ntohs(evt.lport);
 
         // Get network namespace id, if kernel supports it
@@ -105,7 +105,7 @@ int kprobe__inet_listen(struct pt_regs *ctx, struct socket *sock, int backlog)
 
         // Get IP
         if (family == AF_INET) {
-            bpf_probe_read(evt.laddr, sizeof(u32), &(inet->inet_rcv_saddr));
+            evt.laddr[0] = inet->inet_rcv_saddr;
             evt.laddr[0] = be32_to_cpu(evt.laddr[0]);
         } else if (family == AF_INET6) {
             bpf_probe_read(evt.laddr, sizeof(evt.laddr),

tools/tcpconnlat.py

@@ -93,14 +93,14 @@ int trace_connect(struct pt_regs *ctx, struct sock *sk)
 // 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 @@ int trace_tcp_rcv_state_process(struct pt_regs *ctx, struct sock *sk)
 
     // 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 @@ int trace_tcp_rcv_state_process(struct pt_regs *ctx, struct sock *sk)
         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;
 }

tools/tcpretrans.py

@@ -70,28 +70,22 @@ struct ipv6_data_t {
 };
 BPF_PERF_OUTPUT(ipv6_events);
 
-static int trace_event(struct pt_regs *ctx, struct sock *sk, int type)
+static int trace_event(struct pt_regs *ctx, struct sock *skp, int type)
 {
-    if (sk == NULL)
+    if (skp == NULL)
         return 0;
     u32 pid = bpf_get_current_pid_tgid();
-    struct sock *skp = NULL;
-    bpf_probe_read(&skp, sizeof(skp), &sk);
 
     // pull in details
-    u16 family = 0, lport = 0, dport = 0;
-    char state = 0;
-    bpf_probe_read(&family, sizeof(family), &skp->__sk_common.skc_family);
-    bpf_probe_read(&lport, sizeof(lport), &skp->__sk_common.skc_num);
-    bpf_probe_read(&dport, sizeof(dport), &skp->__sk_common.skc_dport);
-    bpf_probe_read(&state, sizeof(state), (void *)&skp->__sk_common.skc_state);
+    u16 family = skp->__sk_common.skc_family;
+    u16 lport = skp->__sk_common.skc_num;
+    u16 dport = skp->__sk_common.skc_dport;
+    char state = skp->__sk_common.skc_state;
 
     if (family == AF_INET) {
         struct ipv4_data_t data4 = {.pid = pid, .ip = 4, .type = type};
-        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;
         // lport is host order
         data4.lport = lport;
         data4.dport = ntohs(dport);
@@ -101,9 +95,9 @@ static int trace_event(struct pt_regs *ctx, struct sock *sk, int type)
     } else if (family == AF_INET6) {
         struct ipv6_data_t data6 = {.pid = pid, .ip = 6, .type = type};
         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);
         // lport is host order
         data6.lport = lport;
         data6.dport = ntohs(dport);