diff --git a/.gitignore b/.gitignore index a6d6234..5232656 100644 --- a/.gitignore +++ b/.gitignore @@ -144,3 +144,5 @@ /test-driver /thread_dealloc_unittest /thread_dealloc_unittest.exe +/unwind_bench +/unwind_bench.exe diff --git a/Makefile.am b/Makefile.am index 4867106..b1156fe 100644 --- a/Makefile.am +++ b/Makefile.am @@ -854,6 +854,12 @@ malloc_bench_shared_full_CXXFLAGS = $(PTHREAD_CFLAGS) $(AM_CXXFLAGS) malloc_bench_shared_full_LDFLAGS = $(PTHREAD_CFLAGS) $(TCMALLOC_FLAGS) malloc_bench_shared_full_LDADD = librun_benchmark.la libtcmalloc.la $(PTHREAD_LIBS) +noinst_PROGRAMS += unwind_bench +unwind_bench_SOURCES = benchmark/unwind_bench.cc +unwind_bench_CXXFLAGS = $(PTHREAD_CFLAGS) $(AM_CXXFLAGS) $(NO_BUILTIN_CXXFLAGS) +unwind_bench_LDFLAGS = $(PTHREAD_CFLAGS) $(TCMALLOC_FLAGS) +unwind_bench_LDADD = librun_benchmark.la libtcmalloc.la $(PTHREAD_LIBS) + endif WITH_HEAP_PROFILER_OR_CHECKER binary_trees_SOURCES = benchmark/binary_trees.cc diff --git a/benchmark/unwind_bench.cc b/benchmark/unwind_bench.cc new file mode 100644 index 0000000..839249b --- /dev/null +++ b/benchmark/unwind_bench.cc @@ -0,0 +1,143 @@ +// -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- +#include "config.h" + +#include "base/basictypes.h" +#include "gperftools/stacktrace.h" + +#include +#include +#include +#include +#if HAVE_LIBUNWIND_H +#include +#endif + +#include "run_benchmark.h" + +#if defined(__GNUC__) && defined(__has_attribute) +#if defined(__linux__) && defined(__x86_64__) && defined(_LP64) && __has_attribute(naked) + +#include +#include + +#define BENCHMARK_UCONTEXT_STUFF 1 + +extern "C" void getcontext_light(ucontext_t *ctx); + +#define R(r) offsetof(ucontext_t, uc_mcontext.gregs[r]) + +__attribute__((naked)) +void getcontext_light(ucontext_t *ctx) { + __asm__ __volatile__( + "\tmovq %%rbx, %c0(%%rdi)\n" + "\tmovq %%rbp, %c1(%%rdi)\n" + "\tmovq %%r12, %c2(%%rdi)\n" + "\tmovq %%r13, %c3(%%rdi)\n" + "\tmovq %%r14, %c4(%%rdi)\n" + "\tmovq %%r15, %c5(%%rdi)\n" + + "\tmovq (%%rsp), %%rcx\n" + "\tmovq %%rcx, %c6(%%rdi)\n" + "\tleaq 8(%%rsp), %%rcx\n" /* Exclude the return address. */ + "\tmovq %%rcx, %c7(%%rdi)\n" + "\tret\n" + : : "i" (R(REG_RBX)), + "i" (R(REG_RBP)), + "i" (R(REG_R12)), + "i" (R(REG_R13)), + "i" (R(REG_R14)), + "i" (R(REG_R15)), + "i" (R(REG_RIP)), + "i" (R(REG_RSP))); +} + +#undef R + +#endif +#endif + +#define MAX_FRAMES 2048 +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) { +#if BENCHMARK_UCONTEXT_STUFF + ucontext_t uc; + getcontext_light(&uc); + n = GetStackTraceWithContext(frames, MAX_FRAMES, 0, &uc); +#else + abort(); +#endif + } 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) { +#ifdef __GNUC__ + // aargh, clang is too smart and it optimizes out f1 "loop" even + // despite frame_forcer trick. So lets resort to less portable asm + // volatile thingy. + __asm__ __volatile__ (""); +#endif + 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); +} + +#if BENCHMARK_UCONTEXT_STUFF +static void bench_unwind_context(long iterations, uintptr_t param) { + do { + f1(0, param, MODE_WITH_CONTEXT); + iterations -= param; + } while (iterations > 0); +} +#endif + +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) { +#if BENCHMARK_UCONTEXT_STUFF + report_benchmark("unwind_context", bench_unwind_context, 1024); +#endif + report_benchmark("unwind_no_context", bench_unwind_no_context, 1024); + report_benchmark("unwind_no_op", bench_unwind_no_op, 1024); + +//// 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; +}