blob: 69a31386d8cd97bf06f036268f0abd37e80e39f5 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
* Augment the openat syscall with the contents of the filename pointer argument.
* Test it with:
* perf trace -e tools/perf/examples/bpf/augmented_syscalls.c cat /etc/passwd > /dev/null
* It'll catch some openat syscalls related to the dynamic linked and
* the last one should be the one for '/etc/passwd'.
* This matches what is marshalled into the raw_syscall:sys_enter payload
* expected by the 'perf trace' beautifiers, and can be used by them unmodified,
* which will be done as that feature is implemented in the next csets, for now
* it will appear in a dump done by the default tracepoint handler in 'perf trace',
* that uses bpf_output__fprintf() to just dump those contents, as done with
* the bpf-output event associated with the __bpf_output__ map declared in
* tools/perf/include/bpf/stdio.h.
#include <stdio.h>
struct bpf_map SEC("maps") __augmented_syscalls__ = {
.key_size = sizeof(int),
.value_size = sizeof(u32),
.max_entries = __NR_CPUS__,
struct syscall_enter_openat_args {
unsigned long long common_tp_fields;
long syscall_nr;
long dfd;
char *filename_ptr;
long flags;
long mode;
struct augmented_enter_openat_args {
struct syscall_enter_openat_args args;
char filename[64];
int syscall_enter(openat)(struct syscall_enter_openat_args *args)
struct augmented_enter_openat_args augmented_args;
probe_read(&augmented_args.args, sizeof(augmented_args.args), args);
probe_read_str(&augmented_args.filename, sizeof(augmented_args.filename), args->filename_ptr);
perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU,
&augmented_args, sizeof(augmented_args));
return 1;