summaryrefslogtreecommitdiff
path: root/tools/perf/util/bpf_trace_augment.c
diff options
context:
space:
mode:
Diffstat (limited to 'tools/perf/util/bpf_trace_augment.c')
-rw-r--r--tools/perf/util/bpf_trace_augment.c143
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);
+}