gperftools/benchmark/unwind_bench.cc

90 lines
2.1 KiB
C++

// -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*-
#include "config.h"
#include "base/basictypes.h"
#include "gperftools/stacktrace.h"
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include "sys/ucontext.h"
#if HAVE_LIBUNWIND_H
#include <libunwind.h>
#endif
#include "run_benchmark.h"
extern "C" void getcontext_light(ucontext_t *ctx);
#define MAX_FRAMES 1024
static void *frames[MAX_FRAMES];
enum measure_mode {
MODE_NOOP,
MODE_WITH_CONTEXT,
MODE_WITHOUT_CONTEXT
};
static int ATTRIBUTE_NOINLINE measure_unwind(int maxlevel, int mode) {
int n;
if (mode == MODE_NOOP)
return 0;
if (mode == MODE_WITH_CONTEXT) {
ucontext_t uc;
getcontext_light(&uc);
n = GetStackTraceWithContext(frames, MAX_FRAMES, 0, &uc);
} else {
n = GetStackTrace(frames, MAX_FRAMES, 0);
}
if (n < maxlevel) {
fprintf(stderr, "Expected at least %d frames, got %d\n", maxlevel, n);
abort();
}
return 0;
}
static int ATTRIBUTE_NOINLINE frame_forcer(int rv) {
return rv;
}
static int ATTRIBUTE_NOINLINE f1(int level, int maxlevel, int mode) {
if (level == maxlevel)
return frame_forcer(measure_unwind(maxlevel, mode));
return frame_forcer(f1(level + 1, maxlevel, mode));
}
static void bench_unwind_no_op(long iterations, uintptr_t param) {
do {
f1(0, param, MODE_NOOP);
iterations -= param;
} while (iterations > 0);
}
static void bench_unwind_context(long iterations, uintptr_t param) {
do {
f1(0, param, MODE_WITH_CONTEXT);
iterations -= param;
} while (iterations > 0);
}
static void bench_unwind_no_context(long iterations, uintptr_t param) {
do {
f1(0, param, MODE_WITHOUT_CONTEXT);
iterations -= param;
} while (iterations > 0);
}
int main(void) {
report_benchmark("unwind_no_op", bench_unwind_no_op, 100);
report_benchmark("unwind_context", bench_unwind_context, 100);
report_benchmark("unwind_no_context", bench_unwind_no_context, 100);
//// TODO: somehow this fails at linking step. Figure out why this is missing
// #if HAVE_LIBUNWIND_H
// unw_set_caching_policy(unw_local_addr_space, UNW_CACHE_PER_THREAD);
// #endif
return 0;
}