[PATCH 12/33] perf augmented_raw_syscalls: Reduce perf_event_output() boilerplate

From: Arnaldo Carvalho de Melo
Date: Mon Aug 26 2019 - 21:37:25 EST


From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

Add a augmented__output() helper to reduce the boilerplate of sending
the augmented tracepoint to the PERF_EVENT_ARRAY BPF map associated with
the bpf-output event used to communicate with the userspace perf trace
tool.

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-ln99gt0j4fv0kw0778h6vphm@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
.../examples/bpf/augmented_raw_syscalls.c | 24 +++++++++----------
1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/tools/perf/examples/bpf/augmented_raw_syscalls.c b/tools/perf/examples/bpf/augmented_raw_syscalls.c
index 8fd5ea059903..b80437971d80 100644
--- a/tools/perf/examples/bpf/augmented_raw_syscalls.c
+++ b/tools/perf/examples/bpf/augmented_raw_syscalls.c
@@ -87,6 +87,12 @@ static inline struct augmented_args_payload *augmented_args_payload(void)
return bpf_map_lookup_elem(&augmented_args_tmp, &key);
}

+static inline int augmented__output(void *ctx, struct augmented_args_payload *args, int len)
+{
+ /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */
+ return perf_event_output(ctx, &__augmented_syscalls__, BPF_F_CURRENT_CPU, args, len);
+}
+
static inline
unsigned int augmented_arg__read_str(struct augmented_arg *augmented_arg, const void *arg, unsigned int arg_len)
{
@@ -142,8 +148,7 @@ int sys_enter_connect(struct syscall_enter_args *args)

probe_read(&augmented_args->saddr, socklen, sockaddr_arg);

- /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */
- return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, augmented_args, len + socklen);
+ return augmented__output(args, augmented_args, len + socklen);
}

SEC("!syscalls:sys_enter_sendto")
@@ -162,8 +167,7 @@ int sys_enter_sendto(struct syscall_enter_args *args)

probe_read(&augmented_args->saddr, socklen, sockaddr_arg);

- /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */
- return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, augmented_args, len + socklen);
+ return augmented__output(args, augmented_args, len + socklen);
}

SEC("!syscalls:sys_enter_open")
@@ -178,8 +182,7 @@ int sys_enter_open(struct syscall_enter_args *args)

len += augmented_arg__read_str(&augmented_args->arg, filename_arg, sizeof(augmented_args->arg.value));

- /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */
- return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, augmented_args, len);
+ return augmented__output(args, augmented_args, len);
}

SEC("!syscalls:sys_enter_openat")
@@ -194,8 +197,7 @@ int sys_enter_openat(struct syscall_enter_args *args)

len += augmented_arg__read_str(&augmented_args->arg, filename_arg, sizeof(augmented_args->arg.value));

- /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */
- return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, augmented_args, len);
+ return augmented__output(args, augmented_args, len);
}

SEC("!syscalls:sys_enter_rename")
@@ -212,8 +214,7 @@ int sys_enter_rename(struct syscall_enter_args *args)
oldpath_len = augmented_arg__read_str(&augmented_args->arg, oldpath_arg, sizeof(augmented_args->arg.value));
len += oldpath_len + augmented_arg__read_str((void *)(&augmented_args->arg) + oldpath_len, newpath_arg, sizeof(augmented_args->arg.value));

- /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */
- return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, augmented_args, len);
+ return augmented__output(args, augmented_args, len);
}

SEC("!syscalls:sys_enter_renameat")
@@ -230,8 +231,7 @@ int sys_enter_renameat(struct syscall_enter_args *args)
oldpath_len = augmented_arg__read_str(&augmented_args->arg, oldpath_arg, sizeof(augmented_args->arg.value));
len += oldpath_len + augmented_arg__read_str((void *)(&augmented_args->arg) + oldpath_len, newpath_arg, sizeof(augmented_args->arg.value));

- /* If perf_event_output fails, return non-zero so that it gets recorded unaugmented */
- return perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, augmented_args, len);
+ return augmented__output(args, augmented_args, len);
}

SEC("raw_syscalls:sys_enter")
--
2.21.0