From: Adrian Hunter Date: Fri, 28 Jun 2013 13:22:19 +0000 (+0300) Subject: perf tools: Add test for converting perf time to/from TSC X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=3bd5a5fc8c6b9fe769777abf74b0ab5fbd7930b4;p=linux-beck.git perf tools: Add test for converting perf time to/from TSC The test uses the newly added cap_usr_time_zero and time_zero of perf_event_mmap_page. TSC from rdtsc is compared with the time from 2 perf events. The test passes if the calculated times are all in the correct order. Signed-off-by: Adrian Hunter Signed-off-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Link: http://lkml.kernel.org/r/1372425741-1676-4-git-send-email-adrian.hunter@intel.com Signed-off-by: Ingo Molnar --- diff --git a/tools/perf/Makefile b/tools/perf/Makefile index 024680b23ddc..bfd12d02a304 100644 --- a/tools/perf/Makefile +++ b/tools/perf/Makefile @@ -389,6 +389,9 @@ LIB_OBJS += $(OUTPUT)tests/bp_signal.o LIB_OBJS += $(OUTPUT)tests/bp_signal_overflow.o LIB_OBJS += $(OUTPUT)tests/task-exit.o LIB_OBJS += $(OUTPUT)tests/sw-clock.o +ifeq ($(ARCH),x86) +LIB_OBJS += $(OUTPUT)tests/perf-time-to-tsc.o +endif BUILTIN_OBJS += $(OUTPUT)builtin-annotate.o BUILTIN_OBJS += $(OUTPUT)builtin-bench.o diff --git a/tools/perf/arch/x86/Makefile b/tools/perf/arch/x86/Makefile index 815841c04eb2..8801fe02f206 100644 --- a/tools/perf/arch/x86/Makefile +++ b/tools/perf/arch/x86/Makefile @@ -6,3 +6,5 @@ ifndef NO_LIBUNWIND LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/unwind.o endif LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/header.o +LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/tsc.o +LIB_H += arch/$(ARCH)/util/tsc.h diff --git a/tools/perf/arch/x86/util/tsc.c b/tools/perf/arch/x86/util/tsc.c new file mode 100644 index 000000000000..f1117441cdcd --- /dev/null +++ b/tools/perf/arch/x86/util/tsc.c @@ -0,0 +1,59 @@ +#include +#include + +#include + +#include "../../perf.h" +#include "../../util/types.h" +#include "../../util/debug.h" +#include "tsc.h" + +u64 perf_time_to_tsc(u64 ns, struct perf_tsc_conversion *tc) +{ + u64 time, quot, rem; + + time = ns - tc->time_zero; + quot = time / tc->time_mult; + rem = time % tc->time_mult; + return (quot << tc->time_shift) + + (rem << tc->time_shift) / tc->time_mult; +} + +u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc) +{ + u64 quot, rem; + + quot = cyc >> tc->time_shift; + rem = cyc & ((1 << tc->time_shift) - 1); + return tc->time_zero + quot * tc->time_mult + + ((rem * tc->time_mult) >> tc->time_shift); +} + +int perf_read_tsc_conversion(const struct perf_event_mmap_page *pc, + struct perf_tsc_conversion *tc) +{ + bool cap_usr_time_zero; + u32 seq; + int i = 0; + + while (1) { + seq = pc->lock; + rmb(); + tc->time_mult = pc->time_mult; + tc->time_shift = pc->time_shift; + tc->time_zero = pc->time_zero; + cap_usr_time_zero = pc->cap_usr_time_zero; + rmb(); + if (pc->lock == seq && !(seq & 1)) + break; + if (++i > 10000) { + pr_debug("failed to get perf_event_mmap_page lock\n"); + return -EINVAL; + } + } + + if (!cap_usr_time_zero) + return -EOPNOTSUPP; + + return 0; +} diff --git a/tools/perf/arch/x86/util/tsc.h b/tools/perf/arch/x86/util/tsc.h new file mode 100644 index 000000000000..a24dec81c795 --- /dev/null +++ b/tools/perf/arch/x86/util/tsc.h @@ -0,0 +1,20 @@ +#ifndef TOOLS_PERF_ARCH_X86_UTIL_TSC_H__ +#define TOOLS_PERF_ARCH_X86_UTIL_TSC_H__ + +#include "../../util/types.h" + +struct perf_tsc_conversion { + u16 time_shift; + u32 time_mult; + u64 time_zero; +}; + +struct perf_event_mmap_page; + +int perf_read_tsc_conversion(const struct perf_event_mmap_page *pc, + struct perf_tsc_conversion *tc); + +u64 perf_time_to_tsc(u64 ns, struct perf_tsc_conversion *tc); +u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc); + +#endif /* TOOLS_PERF_ARCH_X86_UTIL_TSC_H__ */ diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c index 35b45f1466b5..b7b4049fabbb 100644 --- a/tools/perf/tests/builtin-test.c +++ b/tools/perf/tests/builtin-test.c @@ -93,6 +93,12 @@ static struct test { .desc = "Test software clock events have valid period values", .func = test__sw_clock_freq, }, +#if defined(__x86_64__) || defined(__i386__) + { + .desc = "Test converting perf time to TSC", + .func = test__perf_time_to_tsc, + }, +#endif { .func = NULL, }, diff --git a/tools/perf/tests/perf-time-to-tsc.c b/tools/perf/tests/perf-time-to-tsc.c new file mode 100644 index 000000000000..0ab61b1f408e --- /dev/null +++ b/tools/perf/tests/perf-time-to-tsc.c @@ -0,0 +1,177 @@ +#include +#include +#include +#include +#include + +#include "parse-events.h" +#include "evlist.h" +#include "evsel.h" +#include "thread_map.h" +#include "cpumap.h" +#include "tests.h" + +#include "../arch/x86/util/tsc.h" + +#define CHECK__(x) { \ + while ((x) < 0) { \ + pr_debug(#x " failed!\n"); \ + goto out_err; \ + } \ +} + +#define CHECK_NOT_NULL__(x) { \ + while ((x) == NULL) { \ + pr_debug(#x " failed!\n"); \ + goto out_err; \ + } \ +} + +static u64 rdtsc(void) +{ + unsigned int low, high; + + asm volatile("rdtsc" : "=a" (low), "=d" (high)); + + return low | ((u64)high) << 32; +} + +/** + * test__perf_time_to_tsc - test converting perf time to TSC. + * + * This function implements a test that checks that the conversion of perf time + * to and from TSC is consistent with the order of events. If the test passes + * %0 is returned, otherwise %-1 is returned. If TSC conversion is not + * supported then then the test passes but " (not supported)" is printed. + */ +int test__perf_time_to_tsc(void) +{ + struct perf_record_opts opts = { + .mmap_pages = UINT_MAX, + .user_freq = UINT_MAX, + .user_interval = ULLONG_MAX, + .freq = 4000, + .target = { + .uses_mmap = true, + }, + .sample_time = true, + }; + struct thread_map *threads = NULL; + struct cpu_map *cpus = NULL; + struct perf_evlist *evlist = NULL; + struct perf_evsel *evsel = NULL; + int err = -1, ret, i; + const char *comm1, *comm2; + struct perf_tsc_conversion tc; + struct perf_event_mmap_page *pc; + union perf_event *event; + u64 test_tsc, comm1_tsc, comm2_tsc; + u64 test_time, comm1_time = 0, comm2_time = 0; + + threads = thread_map__new(-1, getpid(), UINT_MAX); + CHECK_NOT_NULL__(threads); + + cpus = cpu_map__new(NULL); + CHECK_NOT_NULL__(cpus); + + evlist = perf_evlist__new(); + CHECK_NOT_NULL__(evlist); + + perf_evlist__set_maps(evlist, cpus, threads); + + CHECK__(parse_events(evlist, "cycles:u")); + + perf_evlist__config(evlist, &opts); + + evsel = perf_evlist__first(evlist); + + evsel->attr.comm = 1; + evsel->attr.disabled = 1; + evsel->attr.enable_on_exec = 0; + + CHECK__(perf_evlist__open(evlist)); + + CHECK__(perf_evlist__mmap(evlist, UINT_MAX, false)); + + pc = evlist->mmap[0].base; + ret = perf_read_tsc_conversion(pc, &tc); + if (ret) { + if (ret == -EOPNOTSUPP) { + fprintf(stderr, " (not supported)"); + return 0; + } + goto out_err; + } + + perf_evlist__enable(evlist); + + comm1 = "Test COMM 1"; + CHECK__(prctl(PR_SET_NAME, (unsigned long)comm1, 0, 0, 0)); + + test_tsc = rdtsc(); + + comm2 = "Test COMM 2"; + CHECK__(prctl(PR_SET_NAME, (unsigned long)comm2, 0, 0, 0)); + + perf_evlist__disable(evlist); + + for (i = 0; i < evlist->nr_mmaps; i++) { + while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) { + struct perf_sample sample; + + if (event->header.type != PERF_RECORD_COMM || + (pid_t)event->comm.pid != getpid() || + (pid_t)event->comm.tid != getpid()) + continue; + + if (strcmp(event->comm.comm, comm1) == 0) { + CHECK__(perf_evsel__parse_sample(evsel, event, + &sample)); + comm1_time = sample.time; + } + if (strcmp(event->comm.comm, comm2) == 0) { + CHECK__(perf_evsel__parse_sample(evsel, event, + &sample)); + comm2_time = sample.time; + } + } + } + + if (!comm1_time || !comm2_time) + goto out_err; + + test_time = tsc_to_perf_time(test_tsc, &tc); + comm1_tsc = perf_time_to_tsc(comm1_time, &tc); + comm2_tsc = perf_time_to_tsc(comm2_time, &tc); + + pr_debug("1st event perf time %"PRIu64" tsc %"PRIu64"\n", + comm1_time, comm1_tsc); + pr_debug("rdtsc time %"PRIu64" tsc %"PRIu64"\n", + test_time, test_tsc); + pr_debug("2nd event perf time %"PRIu64" tsc %"PRIu64"\n", + comm2_time, comm2_tsc); + + if (test_time <= comm1_time || + test_time >= comm2_time) + goto out_err; + + if (test_tsc <= comm1_tsc || + test_tsc >= comm2_tsc) + goto out_err; + + err = 0; + +out_err: + if (evlist) { + perf_evlist__disable(evlist); + perf_evlist__munmap(evlist); + perf_evlist__close(evlist); + perf_evlist__delete(evlist); + } + if (cpus) + cpu_map__delete(cpus); + if (threads) + thread_map__delete(threads); + + return err; +} diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h index 07a92f9c6712..d22202aa16e9 100644 --- a/tools/perf/tests/tests.h +++ b/tools/perf/tests/tests.h @@ -35,5 +35,6 @@ int test__bp_signal(void); int test__bp_signal_overflow(void); int test__task_exit(void); int test__sw_clock_freq(void); +int test__perf_time_to_tsc(void); #endif /* TESTS_H */