perf augmented_raw_syscalls: Move the probe_read_str to a separate function

One more step into copying multiple filenames to support syscalls like
rename*.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-xdqtjexdyp81oomm1rkzeifl@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/examples/bpf/augmented_raw_syscalls.c b/tools/perf/examples/bpf/augmented_raw_syscalls.c
index c9fd3b4d8e5541d286807dcb8fcfe63187db1239..356513e81ec10c50f85b6d8045c7a18d9c2a4ce2 100644 (file)
--- a/tools/perf/examples/bpf/augmented_raw_syscalls.c
+++ b/tools/perf/examples/bpf/augmented_raw_syscalls.c
@@ -60,11 +60,27 @@ struct augmented_args_filename {
 
 bpf_map(augmented_filename_map, PERCPU_ARRAY, int, struct augmented_args_filename, 1);
 
+static inline
+unsigned int augmented_args__read_filename(struct augmented_args_filename *augmented_args,
+                                          const void *filename_arg, unsigned int filename_len)
+{
+       unsigned int len = sizeof(*augmented_args);
+
+       augmented_args->filename.reserved = 0;
+       augmented_args->filename.size = probe_read_str(&augmented_args->filename.value, filename_len, filename_arg);
+       if (augmented_args->filename.size < sizeof(augmented_args->filename.value)) {
+               len -= sizeof(augmented_args->filename.value) - augmented_args->filename.size;
+               len &= sizeof(augmented_args->filename.value) - 1;
+       }
+
+       return len;
+}
+
 SEC("raw_syscalls:sys_enter")
 int sys_enter(struct syscall_enter_args *args)
 {
        struct augmented_args_filename *augmented_args;
-       unsigned int len = sizeof(*augmented_args), filename_len;
+       unsigned int len, filename_len;
        const void *filename_arg = NULL;
        struct syscall *syscall;
        int key = 0;
@@ -182,14 +198,7 @@ processed 46 insns (limit 1000000) max_states_per_insn 0 total_states 12 peak_st
        loop_iter_last(5)
 
        if (filename_arg != NULL && filename_len <= sizeof(augmented_args->filename.value)) {
-               augmented_args->filename.reserved = 0;
-               augmented_args->filename.size = probe_read_str(&augmented_args->filename.value,
-                                                             filename_len,
-                                                             filename_arg);
-               if (augmented_args->filename.size < sizeof(augmented_args->filename.value)) {
-                       len -= sizeof(augmented_args->filename.value) - augmented_args->filename.size;
-                       len &= sizeof(augmented_args->filename.value) - 1;
-               }
+               len = augmented_args__read_filename(augmented_args, filename_arg, filename_len);
        } else {
                len = sizeof(augmented_args->args);
        }