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authorMark Brown <broonie@kernel.org>2020-12-11 17:47:55 +0000
committerMark Brown <broonie@kernel.org>2020-12-11 17:47:55 +0000
commit031616c434db05ce766f76c62865f55698e0924f (patch)
tree7f29aa1ff3e7b51a8058cd570fb785c6e769b245 /tools/testing/selftests/bpf/trace_helpers.c
parent064841ccfc49b2315dc0b797239862d3a343aa07 (diff)
parent85a7555575a0e48f9b73db310d0d762a08a46d63 (diff)
Merge remote-tracking branch 'asoc/for-5.10' into asoc-linus
Diffstat (limited to 'tools/testing/selftests/bpf/trace_helpers.c')
-rw-r--r--tools/testing/selftests/bpf/trace_helpers.c27
1 files changed, 27 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c
index 4d0e913bbb22..1bbd1d9830c8 100644
--- a/tools/testing/selftests/bpf/trace_helpers.c
+++ b/tools/testing/selftests/bpf/trace_helpers.c
@@ -90,6 +90,33 @@ long ksym_get_addr(const char *name)
return 0;
}
+/* open kallsyms and read symbol addresses on the fly. Without caching all symbols,
+ * this is faster than load + find.
+ */
+int kallsyms_find(const char *sym, unsigned long long *addr)
+{
+ char type, name[500];
+ unsigned long long value;
+ int err = 0;
+ FILE *f;
+
+ f = fopen("/proc/kallsyms", "r");
+ if (!f)
+ return -EINVAL;
+
+ while (fscanf(f, "%llx %c %499s%*[^\n]\n", &value, &type, name) > 0) {
+ if (strcmp(name, sym) == 0) {
+ *addr = value;
+ goto out;
+ }
+ }
+ err = -ENOENT;
+
+out:
+ fclose(f);
+ return err;
+}
+
void read_trace_pipe(void)
{
int trace_fd;