diff options
Diffstat (limited to 'tools/perf/util/bpf_trace_augment.c')
-rw-r--r-- | tools/perf/util/bpf_trace_augment.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/tools/perf/util/bpf_trace_augment.c b/tools/perf/util/bpf_trace_augment.c new file mode 100644 index 000000000000..56ed17534caa --- /dev/null +++ b/tools/perf/util/bpf_trace_augment.c @@ -0,0 +1,143 @@ +#include <bpf/libbpf.h> +#include <internal/xyarray.h> + +#include "util/debug.h" +#include "util/evlist.h" +#include "util/trace_augment.h" + +#include "bpf_skel/augmented_raw_syscalls.skel.h" + +static struct augmented_raw_syscalls_bpf *skel; +static struct evsel *bpf_output; + +int augmented_syscalls__prepare(void) +{ + struct bpf_program *prog; + char buf[128]; + int err; + + skel = augmented_raw_syscalls_bpf__open(); + if (!skel) { + pr_debug("Failed to open augmented syscalls BPF skeleton\n"); + return -errno; + } + + /* + * Disable attaching the BPF programs except for sys_enter and + * sys_exit that tail call into this as necessary. + */ + bpf_object__for_each_program(prog, skel->obj) { + if (prog != skel->progs.sys_enter && prog != skel->progs.sys_exit) + bpf_program__set_autoattach(prog, /*autoattach=*/false); + } + + err = augmented_raw_syscalls_bpf__load(skel); + if (err < 0) { + libbpf_strerror(err, buf, sizeof(buf)); + pr_debug("Failed to load augmented syscalls BPF skeleton: %s\n", buf); + return err; + } + + augmented_raw_syscalls_bpf__attach(skel); + return 0; +} + +int augmented_syscalls__create_bpf_output(struct evlist *evlist) +{ + int err = parse_event(evlist, "bpf-output/no-inherit=1,name=__augmented_syscalls__/"); + + if (err) { + pr_err("ERROR: Setup BPF output event failed: %d\n", err); + return err; + } + + bpf_output = evlist__last(evlist); + assert(evsel__name_is(bpf_output, "__augmented_syscalls__")); + + return 0; +} + +void augmented_syscalls__setup_bpf_output(void) +{ + struct perf_cpu cpu; + int i; + + if (bpf_output == NULL) + return; + + /* + * Set up the __augmented_syscalls__ BPF map to hold for each + * CPU the bpf-output event's file descriptor. + */ + perf_cpu_map__for_each_cpu(cpu, i, bpf_output->core.cpus) { + int mycpu = cpu.cpu; + + bpf_map__update_elem(skel->maps.__augmented_syscalls__, + &mycpu, sizeof(mycpu), + xyarray__entry(bpf_output->core.fd, + mycpu, 0), + sizeof(__u32), BPF_ANY); + } +} + +int augmented_syscalls__set_filter_pids(unsigned int nr, pid_t *pids) +{ + bool value = true; + int err = 0; + + if (skel == NULL) + return 0; + + for (size_t i = 0; i < nr; ++i) { + err = bpf_map__update_elem(skel->maps.pids_filtered, &pids[i], + sizeof(*pids), &value, sizeof(value), + BPF_ANY); + if (err) + break; + } + return err; +} + +int augmented_syscalls__get_map_fds(int *enter_fd, int *exit_fd, int *beauty_fd) +{ + if (skel == NULL) + return -1; + + *enter_fd = bpf_map__fd(skel->maps.syscalls_sys_enter); + *exit_fd = bpf_map__fd(skel->maps.syscalls_sys_exit); + *beauty_fd = bpf_map__fd(skel->maps.beauty_map_enter); + + if (*enter_fd < 0 || *exit_fd < 0 || *beauty_fd < 0) { + pr_err("Error: failed to get syscall or beauty map fd\n"); + return -1; + } + + return 0; +} + +struct bpf_program *augmented_syscalls__unaugmented(void) +{ + return skel->progs.syscall_unaugmented; +} + +struct bpf_program *augmented_syscalls__find_by_title(const char *name) +{ + struct bpf_program *pos; + const char *sec_name; + + if (skel->obj == NULL) + return NULL; + + bpf_object__for_each_program(pos, skel->obj) { + sec_name = bpf_program__section_name(pos); + if (sec_name && !strcmp(sec_name, name)) + return pos; + } + + return NULL; +} + +void augmented_syscalls__cleanup(void) +{ + augmented_raw_syscalls_bpf__destroy(skel); +} |