#include <darwintest.h>
#include <dispatch/dispatch.h>
#include <ktrace/ktrace.h>
#include <kern/debug.h>
#include <sys/kdebug.h>
#include <TargetConditionals.h>
enum telemetry_pmi {
TELEMETRY_PMI_NONE,
TELEMETRY_PMI_INSTRS,
TELEMETRY_PMI_CYCLES,
};
#define TELEMETRY_CMD_PMI_SETUP 3
T_GLOBAL_META(T_META_NAMESPACE("xnu.debugging.telemetry"),
T_META_CHECK_LEAKS(false),
T_META_ASROOT(true));
extern int __telemetry(uint64_t cmd, uint64_t deadline, uint64_t interval,
uint64_t leeway, uint64_t arg4, uint64_t arg5);
static void
telemetry_cleanup(void)
{
int ret = __telemetry(TELEMETRY_CMD_PMI_SETUP, TELEMETRY_PMI_NONE, 0, 0, 0, 0);
T_EXPECT_POSIX_SUCCESS(ret, "telemetry(... NONE ...)");
}
volatile static bool spinning = true;
static void *
thread_spin(__unused void *arg)
{
while (spinning) {
}
return NULL;
}
#define MT_MICROSTACKSHOT KDBG_EVENTID(DBG_MONOTONIC, 2, 1)
#define MS_RECORD MACHDBG_CODE(DBG_MACH_STACKSHOT, \
MICROSTACKSHOT_RECORD)
#if defined(__arm64__) || defined(__arm__)
#define INSTRS_PERIOD (100ULL * 1000 * 1000)
#else
#define INSTRS_PERIOD (1ULL * 1000 * 1000 * 1000)
#endif
#define SLEEP_SECS 10
T_DECL(microstackshot_pmi, "attempt to configure microstackshots on PMI")
{
#if TARGET_OS_WATCH
T_SKIP("unsupported platform");
#endif
T_SETUPBEGIN;
ktrace_session_t s = ktrace_session_create();
T_QUIET; T_WITH_ERRNO; T_ASSERT_NOTNULL(s, "session create");
__block int pmi_events = 0;
__block int microstackshot_record_events = 0;
__block int pmi_records = 0;
__block int io_records = 0;
__block int interrupt_records = 0;
__block int timer_arm_records = 0;
__block int unknown_records = 0;
__block int multi_records = 0;
ktrace_events_single(s, MT_MICROSTACKSHOT, ^(__unused struct trace_point *tp) {
pmi_events++;
});
ktrace_events_single_paired(s, MS_RECORD,
^(struct trace_point *start, __unused struct trace_point *end) {
if (start->arg1 & kPMIRecord) {
pmi_records++;
}
if (start->arg1 & kIORecord) {
io_records++;
}
if (start->arg1 & kInterruptRecord) {
interrupt_records++;
}
if (start->arg1 & kTimerArmingRecord) {
timer_arm_records++;
}
const uint8_t any_record = kPMIRecord | kIORecord | kInterruptRecord |
kTimerArmingRecord;
if ((start->arg1 & any_record) == 0) {
unknown_records++;
}
if (__builtin_popcount(start->arg1 & any_record) != 1) {
multi_records++;
}
microstackshot_record_events++;
});
ktrace_set_completion_handler(s, ^{
ktrace_session_destroy(s);
T_EXPECT_GT(pmi_events, 0,
"saw non-zero PMIs (%g/sec)", pmi_events / (double)SLEEP_SECS);
T_EXPECT_GT(pmi_records, 0, "saw non-zero PMI record events (%g/sec)",
pmi_records / (double)SLEEP_SECS);
T_EXPECT_EQ(unknown_records, 0, "saw zero unknown record events");
T_EXPECT_EQ(multi_records, 0, "saw zero multiple record events");
T_EXPECT_GT(microstackshot_record_events, 0,
"saw non-zero microstackshot record events (%g/sec)",
microstackshot_record_events / (double)SLEEP_SECS);
if (interrupt_records > 0) {
T_LOG("saw %g interrupt records per second",
interrupt_records / (double)SLEEP_SECS);
} else {
T_LOG("saw no interrupt records");
}
if (io_records > 0) {
T_LOG("saw %g I/O records per second",
io_records / (double)SLEEP_SECS);
} else {
T_LOG("saw no I/O records");
}
if (timer_arm_records > 0) {
T_LOG("saw %g timer arming records per second",
timer_arm_records / (double)SLEEP_SECS);
} else {
T_LOG("saw no timer arming records");
}
T_END;
});
T_SETUPEND;
int ret = __telemetry(TELEMETRY_CMD_PMI_SETUP, TELEMETRY_PMI_INSTRS,
INSTRS_PERIOD, 0, 0, 0);
if (ret < 0 && errno == EBUSY) {
T_PASS("telemetry is busy/active, maybe the events will be seen");
} else {
T_ASSERT_POSIX_SUCCESS(ret,
"telemetry syscall succeeded, started microstackshots");
T_LOG("installing cleanup handler");
T_ATEND(telemetry_cleanup);
}
pthread_t thread;
int error = pthread_create(&thread, NULL, thread_spin, NULL);
T_ASSERT_POSIX_ZERO(error, "started thread to spin");
error = ktrace_start(s, dispatch_get_main_queue());
T_ASSERT_POSIX_ZERO(error, "started tracing");
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, SLEEP_SECS * NSEC_PER_SEC),
dispatch_get_main_queue(), ^{
spinning = false;
ktrace_end(s, 0);
(void)pthread_join(thread, NULL);
T_LOG("ending trace session after %d seconds", SLEEP_SECS);
});
dispatch_main();
}
T_DECL(error_handling,
"ensure that error conditions for the telemetry syscall are observed")
{
int ret = __telemetry(TELEMETRY_CMD_PMI_SETUP, TELEMETRY_PMI_INSTRS,
1, 0, 0, 0);
T_EXPECT_EQ(ret, -1, "telemetry shouldn't allow PMI every instruction");
ret = __telemetry(TELEMETRY_CMD_PMI_SETUP, TELEMETRY_PMI_INSTRS,
1000 * 1000, 0, 0, 0);
T_EXPECT_EQ(ret, -1,
"telemetry shouldn't allow PMI every million instructions");
ret = __telemetry(TELEMETRY_CMD_PMI_SETUP, TELEMETRY_PMI_CYCLES,
1, 0, 0, 0);
T_EXPECT_EQ(ret, -1, "telemetry shouldn't allow PMI every cycle");
ret = __telemetry(TELEMETRY_CMD_PMI_SETUP, TELEMETRY_PMI_CYCLES,
1000 * 1000, 0, 0, 0);
T_EXPECT_EQ(ret, -1,
"telemetry shouldn't allow PMI every million cycles");
}