#include <mach/mach_time.h>
#include <mach/mach.h>
#include <machine/cpu_capabilities.h>
#include <os/atomic_private.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/commpage.h>
#include <sys/kdebug.h>

#include <darwintest.h>
#include <darwintest_utils.h>
#include "sched_test_utils.h"

static bool verbosity_enabled = true;

void
disable_verbose_sched_utils(void)
{
	T_QUIET; T_ASSERT_TRUE(verbosity_enabled, "verbosity was enabled");
	verbosity_enabled = false;
}

void
reenable_verbose_sched_utils(void)
{
	T_QUIET; T_ASSERT_EQ(verbosity_enabled, false, "verbosity was disabled");
	verbosity_enabled = true;
}

static mach_timebase_info_data_t timebase_info;

uint64_t
nanos_to_abs(uint64_t nanos)
{
	mach_timebase_info_data_t timebase = timebase_info;

	if (timebase.numer == 0 || timebase.denom == 0) {
		kern_return_t kr;

		kr = mach_timebase_info(&timebase_info);
		T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "mach_timebase_info");

		timebase = timebase_info;
	}
	return nanos * timebase.denom / timebase.numer;
}

uint64_t
abs_to_nanos(uint64_t abs)
{
	mach_timebase_info_data_t timebase = timebase_info;

	if (timebase.numer == 0 || timebase.denom == 0) {
		kern_return_t kr;
		kr = mach_timebase_info(&timebase_info);
		T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "mach_timebase_info");
		timebase = timebase_info;
	}
	return abs * timebase.numer / timebase.denom;
}

static int num_perf_levels = 0;
unsigned int
platform_nperflevels(void)
{
	if (num_perf_levels == 0) {
		int ret;
		ret = sysctlbyname("hw.nperflevels", &num_perf_levels, &(size_t){ sizeof(num_perf_levels) }, NULL, 0);
		T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "hw.nperflevels");
	}
	return (unsigned int)num_perf_levels;
}

static char perflevel_names[64][16];
const char *
platform_perflevel_name(unsigned int perflevel)
{
	if (perflevel_names[perflevel][0] == 0) {
		int ret;
		char sysctl_name[64] = { 0 };
		snprintf(sysctl_name, sizeof(sysctl_name), "hw.perflevel%d.name", perflevel);
		ret = sysctlbyname(sysctl_name, &perflevel_names[perflevel], &(size_t){ sizeof(perflevel_names[perflevel]) }, NULL, 0);
		T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "%s", sysctl_name);
	}
	return (const char *)perflevel_names[perflevel];
}

static unsigned int perflevel_ncpus[64] = {0};
unsigned int
platform_perflevel_ncpus(unsigned int perflevel)
{
	if (perflevel_ncpus[perflevel] == 0) {
		int ret;
		char sysctl_name[64] = { 0 };
		snprintf(sysctl_name, sizeof(sysctl_name), "hw.perflevel%d.logicalcpu", perflevel);
		ret = sysctlbyname(sysctl_name, &perflevel_ncpus[perflevel], &(size_t){ sizeof(perflevel_ncpus[perflevel]) }, NULL, 0);
		T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "%s", sysctl_name);
	}
	return perflevel_ncpus[perflevel];
}

static bool reported_is_amp = false;
bool
platform_is_amp(void)
{
	bool is_amp = platform_nperflevels() > 1;
	if (verbosity_enabled && !reported_is_amp) {
		T_LOG("🛰️ Platform has %d perflevels (%s)", platform_nperflevels(), is_amp ? "AMP" : "SMP");
		reported_is_amp = true;
	}
	return is_amp;
}

bool
platform_is_virtual_machine(void)
{
	int ret;
	int vmm_present = 0;
	ret = sysctlbyname("kern.hv_vmm_present", &vmm_present, &(size_t){ sizeof(vmm_present) }, NULL, 0);
	T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "kern.hv_vmm_present");
	if (vmm_present) {
		if (verbosity_enabled) {
			T_LOG("🛰️ Platform is a virtual machine!");
		}
		return true;
	}

	return false;
}

static char sched_policy_name[64];
char *
platform_sched_policy(void)
{
	int ret;
	ret = sysctlbyname("kern.sched", sched_policy_name, &(size_t){ sizeof(sched_policy_name) }, NULL, 0);
	T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "kern.sched");
	if (verbosity_enabled) {
		T_LOG("🛰️ Platform is running the \"%s\" scheduler policy", sched_policy_name);
	}
	return sched_policy_name;
}

static uint8_t num_clusters = 0;

unsigned int
platform_num_clusters(void)
{
	if (num_clusters == 0) {
		num_clusters = COMM_PAGE_READ(uint8_t, CPU_CLUSTERS);
		if (verbosity_enabled) {
			T_LOG("🛰️ Platform has %u CPU clusters", num_clusters);
		}
	}
	return num_clusters;
}

char
bind_to_cluster_of_type(char type)
{
	int ret;
	char old_type;
	ret = sysctlbyname("kern.sched_thread_bind_cluster_type",
	    &old_type, &(size_t){ sizeof(old_type) }, &type, sizeof(type));
	T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "kern.sched_thread_bind_cluster_type");
	return old_type;
}

int
bind_to_cluster_id(int cluster_id)
{
	int ret;
	int old_cluster = 0;
	ret = sysctlbyname("kern.sched_thread_bind_pset_id", &old_cluster,
	    &(size_t){ sizeof(old_cluster) }, &cluster_id, sizeof(cluster_id));
	T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "kern.sched_thread_bind_pset_id");
	return old_cluster;
}

static volatile _Atomic int stop_spinning_flag = 0;

void
stop_spinning_threads(void)
{
	os_atomic_store(&stop_spinning_flag, 1, release);
}

void
spin_for_duration(uint32_t seconds)
{
	uint64_t duration       = nanos_to_abs((uint64_t)seconds * NSEC_PER_SEC);
	uint64_t current_time   = mach_absolute_time();
	uint64_t timeout        = duration + current_time;

	uint64_t spin_count = 0;

	while ((mach_absolute_time() < timeout) &&
	    (os_atomic_load(&stop_spinning_flag, acquire) == 0)) {
		spin_count++;
	}
}

pthread_attr_t *
create_pthread_attr(int priority,
    detach_state_t detach_state, qos_class_t qos_class,
    sched_policy_t sched_policy, size_t stack_size)
{
	int ret;
	pthread_attr_t *attr = (pthread_attr_t *)malloc(sizeof(pthread_attr_t));
	ret = pthread_attr_init(attr);
	T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "pthread_attr_init");

	struct sched_param param = { .sched_priority = priority };
	ret = pthread_attr_setschedparam(attr, &param);
	T_QUIET; T_ASSERT_POSIX_ZERO(ret, "pthread_attr_setschedparam");

	if (detach_state == eDetached) {
		ret = pthread_attr_setdetachstate(attr, PTHREAD_CREATE_DETACHED);
		T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "pthread_attr_setdetachstate");
	}

	if (qos_class != QOS_CLASS_UNSPECIFIED) {
		ret = pthread_attr_set_qos_class_np(attr, qos_class, 0);
		T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "pthread_attr_set_qos_class_np");
	}

	if (sched_policy != eSchedDefault) {
		int sched_policy_val = 0;
		switch (sched_policy) {
		case eSchedFIFO:
			sched_policy_val = SCHED_FIFO;
			break;
		case eSchedRR:
			sched_policy_val = SCHED_RR;
			break;
		case eSchedOther:
			sched_policy_val = SCHED_OTHER;
			break;
		case eSchedDefault:
			T_QUIET; T_ASSERT_FAIL("unexpected sched_policy");
			break;
		}
		ret = pthread_attr_setschedpolicy(attr, (int)sched_policy);
		T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "pthread_attr_setschedpolicy");
	}

	if (stack_size != DEFAULT_STACK_SIZE) {
		ret = pthread_attr_setstacksize(attr, stack_size);
		T_QUIET; T_ASSERT_POSIX_ZERO(ret, "pthread_attr_setstacksize");
	}
	return attr;
}

void
create_thread(pthread_t *thread_handle, pthread_attr_t *attr,
    void *(*func)(void *), void *arg)
{
	int ret;
	ret = pthread_create(thread_handle, attr, func, arg);
	T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "pthread_create");
}

void
create_thread_pri(pthread_t *thread_handle, int priority,
    void *(*func)(void *), void *arg)
{
	pthread_attr_t *attr = create_pthread_attr(priority, eJoinable,
	    QOS_CLASS_UNSPECIFIED, eSchedDefault, DEFAULT_STACK_SIZE);
	create_thread(thread_handle, attr, func, arg);
}

pthread_t *
create_threads(int num_threads, int priority,
    detach_state_t detach_state, qos_class_t qos_class,
    sched_policy_t sched_policy, size_t stack_size,
    void *(*func)(void *), void *arg_array[])
{
	pthread_attr_t *attr = create_pthread_attr(priority, detach_state,
	    qos_class, sched_policy, stack_size);

	pthread_t *thread_handles = (pthread_t *)malloc(sizeof(pthread_t) * (size_t)num_threads);
	for (int i = 0; i < num_threads; i++) {
		create_thread(&thread_handles[i], attr, func, arg_array == NULL ? NULL : arg_array[i]);
	}
	return thread_handles;
}

const char *
platform_train_descriptor(void)
{
#if TARGET_OS_XR
	return "visionOS";
#elif TARGET_OS_TV
	return "tvOS";
#elif TARGET_OS_WATCH
	return "watchOS";
#elif TARGET_OS_BRIDGE
	return "bridgeOS";
#elif TARGET_OS_OSX
	return "macOS";
#elif TARGET_OS_IOS
	return "iOS";
#else
	return "unknown";
#endif
}

static const double default_idle_threshold = 0.9;
static const int default_timeout_sec = 3;

bool
wait_for_quiescence_default(int argc, char *const argv[])
{
	return wait_for_quiescence(argc, argv, default_idle_threshold, default_timeout_sec);
}

/* Logic taken from __wait_for_quiescence in qos_tests.c */
bool
wait_for_quiescence(int argc, char *const argv[], double idle_threshold, int timeout_seconds)
{
	kern_return_t kr;

	for (int i = 0; i < argc; i++) {
		if (strcmp(argv[i], "--no-quiesce") == 0) {
			T_LOG("🕒 Skipping quiescence due to \"--no-quiesce\"");
			return true;
		}
	}

	bool quiesced = false;
	double idle_ratio = 0.0;
	if (verbosity_enabled) {
		T_LOG("🕒 Waiting up to %d second(s) for the system to quiesce above %.2f%% idle...",
		    timeout_seconds, idle_threshold * 100.0);
	}

	host_cpu_load_info_data_t host_load;
	mach_msg_type_number_t count = HOST_CPU_LOAD_INFO_COUNT;
	int waited_seconds = 0;
	int ind = 0;
	double user_ticks[2];
	double system_ticks[2];
	double idle_ticks[2];

	while (waited_seconds < timeout_seconds) {
		kr = host_statistics(mach_host_self(), HOST_CPU_LOAD_INFO, (host_info_t)&host_load, &count);
		T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "host_statistics HOST_CPU_LOAD_INFO");

		user_ticks[ind] = (double)host_load.cpu_ticks[CPU_STATE_USER];
		system_ticks[ind] = (double)host_load.cpu_ticks[CPU_STATE_SYSTEM];
		idle_ticks[ind] = (double)host_load.cpu_ticks[CPU_STATE_IDLE];

		if (waited_seconds >= 1) {
			int old_ind = (ind + 1) % 2;
			double idle_delta = idle_ticks[ind] - idle_ticks[old_ind];
			double total_delta = idle_delta + (user_ticks[ind] - user_ticks[old_ind]) + (system_ticks[ind] - system_ticks[old_ind]);
			if (total_delta > 0.0) {
				idle_ratio = idle_delta / total_delta;
				if (idle_ratio >= idle_threshold) {
					quiesced = true;
					break;
				}
				if (verbosity_enabled) {
					T_LOG("🕒 Not yet quiesced (%.2f%% idle)", idle_ratio * 100.0);
				}
			}
		}

		sleep(1);
		ind = (ind + 1) % 2;
		waited_seconds++;
	}

	if (verbosity_enabled) {
		if (quiesced) {
			T_LOG("🕒 System quiesced to %.2f%% idle within %d second(s)", idle_ratio * 100.0, waited_seconds);
		} else {
			T_LOG("🕒 Failed to quiesce within %.2f%% idle after %d second(s)", idle_threshold * 100.0, waited_seconds);
		}
	}
	return quiesced;
}

static bool atend_handler_registered = false;

static void
sched_utils_sigint_handler(int sig)
{
	T_QUIET; T_EXPECT_EQ(sig, SIGINT, "unexpected signal received");
	T_ASSERT_TRUE(false, "SIGINT received. Failing test to induce ATEND handlers for cleanup...");
}

static void
register_atend_handler(void)
{
	if (!atend_handler_registered) {
		signal(SIGINT, sched_utils_sigint_handler);
		atend_handler_registered = true;
	}
}

static char *clpcctrl_bin = "/usr/local/bin/clpcctrl";
static bool setup_clpcctrl_atend = false;

static void
clpcctrl_cleanup(void)
{
	T_LOG("🏎️ Restoring CLPC state...");

	char *recommend_all_cores_args[] = {"-C", "all", NULL};
	execute_clpcctrl(recommend_all_cores_args, false);

	char *restore_dynamic_control_args[] = {"-d", NULL};
	execute_clpcctrl(restore_dynamic_control_args, false);
}

uint64_t
execute_clpcctrl(char *clpcctrl_args[], bool read_value)
{
	int ret;

	/* Avoid recursion during teardown */
	if (!setup_clpcctrl_atend) {
		register_atend_handler();
		T_ATEND(clpcctrl_cleanup);
		setup_clpcctrl_atend = true;
	}

	/* Populate arg array with clpcctrl location */
	char *full_clpcctrl_args[100];
	full_clpcctrl_args[0] = clpcctrl_bin;
	int arg_ind = 0;
	while (clpcctrl_args[arg_ind] != NULL) {
		T_QUIET; T_ASSERT_LT(arg_ind + 1, 100, "too many clpcctrl args");
		full_clpcctrl_args[arg_ind + 1] = clpcctrl_args[arg_ind];
		arg_ind++;
	}
	full_clpcctrl_args[arg_ind + 1] = NULL;

	__block uint64_t value = 0;
	pid_t pid = dt_launch_tool_pipe(full_clpcctrl_args, false, NULL,
	    ^bool (char *data, __unused size_t data_size, __unused dt_pipe_data_handler_context_t *context) {
		T_LOG("🏎️ [clpcctrl] %s", data);
		if (read_value) {
		        char *token = strtok(data, " ");
		        token = strtok(NULL, " ");
		        value = strtoull(token, NULL, 10);
		}
		return false;
	},
	    ^bool (char *data, __unused size_t data_size, __unused dt_pipe_data_handler_context_t *context) {
		T_LOG("🏎️ [clpcctrl] Error msg: %s", data);
		return false;
	},
	    BUFFER_PATTERN_LINE, NULL);

	ret = dt_waitpid(pid, NULL, NULL, 0);
	T_QUIET; T_EXPECT_TRUE(ret, "dt_waitpid for clpcctrl");

	return value;
}

bool
check_recommended_core_mask(uint64_t *core_mask)
{
	int ret;
	uint64_t recommended_cores = 0;
	size_t recommended_cores_size = sizeof(recommended_cores);
	ret = sysctlbyname("kern.sched_recommended_cores", &recommended_cores, &recommended_cores_size, NULL, 0);
	T_QUIET; T_EXPECT_POSIX_SUCCESS(ret, "sysctlbyname(kern.sched_recommended_cores)");

	if (verbosity_enabled) {
		uint64_t expected_recommended_mask = ~0ULL >> (64 - dt_ncpu());
		T_LOG("📈 kern.sched_recommended_cores: %016llx, expecting %016llx if all are recommended",
		    recommended_cores, expected_recommended_mask);
	}

	if (core_mask != NULL) {
		*core_mask = recommended_cores;
	}
	return __builtin_popcountll(recommended_cores) == dt_ncpu();
}

/* Trace Management */

enum trace_status {
	STARTED = 1,
	ENDED = 2,
	SAVED = 3,
	DISCARDED = 4,
};

struct trace_handle {
	char *short_name;
	char *trace_filename;
	char *abs_filename;
	pid_t trace_pid;
	enum trace_status status;
	pid_t wait_on_start_pid;
	pid_t wait_on_end_pid;
};

#define MAX_TRACES 1024
static struct trace_handle handles[MAX_TRACES];
static int handle_ind = 0;

/* Default setting is to record a trace but only save it if the test failed */
static bool tracing_enabled = true;
static bool trace_save_requested = false;

static bool
trace_requested(int argc, char *const argv[])
{
	for (int i = 0; i < argc; i++) {
		if (strcmp(argv[i], "--save-trace") == 0) {
			trace_save_requested = true;
		}
		if (strcmp(argv[i], "--no-trace") == 0) {
			tracing_enabled = false;
		}
	}
	T_QUIET; T_ASSERT_TRUE(tracing_enabled || !trace_save_requested, "Can't use both --save-trace and --no-trace");
	return tracing_enabled;
}

static void
atend_trace_cleanup(void)
{
	int ret;
	for (int i = 0; i < handle_ind; i++) {
		struct trace_handle *handle = &handles[i];
		if (handle->status == STARTED) {
			end_collect_trace(handle);
		}
		T_QUIET; T_EXPECT_EQ(handle->status, ENDED, "ended trace");
		if (handle->status == ENDED && ((T_FAILCOUNT > 0) || trace_save_requested)) {
			/* Save the trace as an artifact for debugging the failure(s) */
			save_collected_trace(handle);
		}
		/* Make sure to free up the tmp dir space we used */
		discard_collected_trace(handle);
		/* Kill trace just in case */
		ret = kill(handle->trace_pid, SIGKILL);
		T_QUIET; T_WITH_ERRNO; T_EXPECT_POSIX_SUCCESS(ret, "kill SIGKILL");
	}
}

static bool
sched_utils_tracing_supported(void)
{
#if TARGET_OS_BRIDGE
	/*
	 * Don't support the tracing on BridgeOS due to limited disk space
	 * and CLPC compatibility issues.
	 */
	return false;
#else /* !TARGET_OS_BRIDGE */
	disable_verbose_sched_utils();
	/* Virtual machines do not support trace */
	bool supported = (platform_is_virtual_machine() == false);
	reenable_verbose_sched_utils();
	return supported;
#endif /* !TARGET_OS_BRIDGE */
}

trace_handle_t
begin_collect_trace(int argc, char *const argv[], char *filename)
{
	return begin_collect_trace_fmt(COLLECT_TRACE_FLAG_NONE, argc, argv, filename);
}
static bool first_trace = true;

static char *trace_bin = "/usr/local/bin/trace";
static char *notifyutil_bin = "/usr/bin/notifyutil";
#if TARGET_OS_OSX
static char *aa_bin = "/usr/bin/aa";
#else
static char *aa_bin = "/usr/local/bin/aa";
#endif

static char *begin_notification = "🖊️_trace_begun...";
static char *end_notification = "🖊️_trace_ended...";
static char *trigger_end_notification = "🖊️_stopping_trace...";

#if !(TARGET_OS_WATCH || TARGET_OS_TV)
static const int waiting_timeout_sec = 60 * 2; /* 2 minutes, allows trace post-processing to finish */
#else /* !(TARGET_OS_WATCH || TARGET_OS_TV) */
static const int waiting_timeout_sec = 60 * 3 + 30; /* 3 minutes and 30 seconds for slower targets */
#endif /* !(TARGET_OS_WATCH || TARGET_OS_TV) */

trace_handle_t
begin_collect_trace_fmt(collect_trace_flags_t flags, int argc, char *const argv[], char *fmt, ...)
{
	/* Check trace requirements */
	if (!sched_utils_tracing_supported() || !trace_requested(argc, argv)) {
		return NULL;
	}
	T_QUIET; T_ASSERT_EQ(geteuid(), 0, "🖊️ Tracing requires the test to be run as root user");

	int ret;
	struct trace_handle *handle = &handles[handle_ind++];
	T_QUIET; T_ASSERT_LE(handle_ind, MAX_TRACES, "Ran out of trace handles");

	/* Generate the trace filename from the formatted string and args */
	char *name = (char *)malloc(sizeof(char) * MAXPATHLEN);
	va_list args;
	va_start(args, fmt);
	vsnprintf(name, MAXPATHLEN, fmt, args);
	va_end(args);
	handle->short_name = name;
	char *full_filename = (char *)malloc(sizeof(char) * MAXPATHLEN);
	memset(full_filename, 0, MAXPATHLEN);
	snprintf(full_filename, MAXPATHLEN, "%s/%s.atrc", dt_tmpdir(), handle->short_name);
	handle->abs_filename = full_filename;
	char *filename = (char *)malloc(sizeof(char) * MAXPATHLEN);
	memset(filename, 0, MAXPATHLEN);
	snprintf(filename, MAXPATHLEN, "%s.atrc", handle->short_name);
	handle->trace_filename = filename;

	/* If filename already exists, delete old trace */
	ret = remove(handle->abs_filename);
	T_QUIET; T_WITH_ERRNO; T_EXPECT_TRUE(ret == 0 || errno == ENOENT, "remove trace file");

	if (first_trace) {
		/* Run tracing cleanup a single time */
		register_atend_handler();
		T_ATEND(atend_trace_cleanup);
		first_trace = false;
	}

	/* Launch procs to monitor trace start/stop */
	char *wait_on_start_args[] = {"/usr/bin/notifyutil", "-1", begin_notification, NULL};
	ret = dt_launch_tool(&handle->wait_on_start_pid, wait_on_start_args, false, NULL, NULL);
	T_QUIET; T_WITH_ERRNO; T_EXPECT_EQ(ret, 0, "dt_launch_tool");
	char *wait_on_end_args[] = {"/usr/bin/notifyutil", "-1", end_notification, NULL};
	ret = dt_launch_tool(&handle->wait_on_end_pid, wait_on_end_args, false, NULL, NULL);
	T_QUIET; T_WITH_ERRNO; T_EXPECT_EQ(ret, 0, "dt_launch_tool");

	/* Launch trace record */
	char *trace_args_base[18] = {trace_bin, "record", handle->abs_filename, "--plan", "default", "--unsafe",
		                     "--kdebug-filter-include", "C0x01",
		                     "--omit", "Logging", "--kdebug-buffer-size", "1gb",
		                     "--notify-after-start", begin_notification, "--notify-after-end", end_notification,
		                     "--end-on-notification", trigger_end_notification};
	const unsigned trace_args_cap = 32; /* INCREASE THIS if there are too many trace args */
	char* trace_args[trace_args_cap];
	unsigned trace_args_len = 0;
	for (unsigned i = 0; i < sizeof(trace_args_base) / sizeof(char *); ++i) {
		trace_args[trace_args_len++] = trace_args_base[i];
		T_QUIET; T_ASSERT_LT(trace_args_len, trace_args_cap, "too many trace args");
	}
	if (flags & COLLECT_TRACE_FLAG_DISABLE_SYSCALLS) {
		trace_args[trace_args_len++] = "--omit=syscalls,syscall-sampling";
		T_QUIET; T_ASSERT_LT(trace_args_len, trace_args_cap, "too many trace args");
		trace_args[trace_args_len++] = "--kdebug-filter-exclude=S0x0103,S0x040c";
		T_QUIET; T_ASSERT_LT(trace_args_len, trace_args_cap, "too many trace args");
	}
	if (flags & COLLECT_TRACE_FLAG_DISABLE_CLUTCH) {
		trace_args[trace_args_len++] = "--kdebug-filter-exclude=S0x01A9";
		T_QUIET; T_ASSERT_LT(trace_args_len, trace_args_cap, "too many trace args");
	}
	trace_args[trace_args_len++] = NULL;
	T_QUIET; T_ASSERT_LT(trace_args_len, trace_args_cap, "too many trace args");

	pid_t trace_pid = dt_launch_tool_pipe(trace_args, false, NULL,
	    ^bool (char *data, __unused size_t data_size, __unused dt_pipe_data_handler_context_t *context) {
		T_LOG("🖊️ [trace] %s", data);
		return false;
	},
	    ^bool (char *data, __unused size_t data_size, __unused dt_pipe_data_handler_context_t *context) {
		T_LOG("🖊️ [trace] Error msg: %s", data);
		return false;
	},
	    BUFFER_PATTERN_LINE, NULL);

	T_LOG("🖊️ Starting trace collection for \"%s\" trace[%u]", handle->trace_filename, trace_pid);

	/* Wait for tracing to start */
	int signal_num = 0;
	ret = dt_waitpid(handle->wait_on_start_pid, NULL, &signal_num, waiting_timeout_sec);
	T_QUIET; T_EXPECT_TRUE(ret, "dt_waitpid for trace start signal_num %d", signal_num);

	handle->trace_pid = trace_pid;
	handle->status = STARTED;

	return (trace_handle_t)handle;
}

void
end_collect_trace(trace_handle_t handle)
{
	if (!sched_utils_tracing_supported() || !tracing_enabled) {
		return;
	}

	int ret;
	struct trace_handle *trace_state = (struct trace_handle *)handle;
	T_QUIET; T_EXPECT_EQ(trace_state->status, STARTED, "trace was started");

	/* Notify trace to stop tracing */
	char *wait_on_start_args[] = {notifyutil_bin, "-p", trigger_end_notification, NULL};
	pid_t trigger_end_pid = 0;
	ret = dt_launch_tool(&trigger_end_pid, wait_on_start_args, false, NULL, NULL);
	T_QUIET; T_WITH_ERRNO; T_EXPECT_EQ(ret, 0, "dt_launch_tool for notify end trace");

	/* Wait for tracing to actually stop */
	T_LOG("🖊️ Now waiting on trace to finish up...");
	int signal_num = 0;
	int exit_status = 0;
	ret = dt_waitpid(trace_state->wait_on_end_pid, &exit_status, &signal_num, waiting_timeout_sec);
	T_QUIET; T_EXPECT_TRUE(ret, "dt_waitpid for trace stop, exit status %d signal_num %d", exit_status, signal_num);

	trace_state->status = ENDED;
}

void
save_collected_trace(trace_handle_t handle)
{
	if (!sched_utils_tracing_supported() || !tracing_enabled) {
		return;
	}

	int ret;
	struct trace_handle *trace_state = (struct trace_handle *)handle;
	T_QUIET; T_EXPECT_EQ(trace_state->status, ENDED, "trace was ended");

	/* Generate compressed filepath and mark for upload */
	char compressed_path[MAXPATHLEN];
	snprintf(compressed_path, MAXPATHLEN, "%s.aar", trace_state->short_name);
	ret = dt_resultfile(compressed_path, MAXPATHLEN);
	T_QUIET; T_WITH_ERRNO; T_EXPECT_POSIX_ZERO(ret, "dt_resultfile marking \"%s\" for collection", compressed_path);
	T_LOG("🖊️ \"%s\" marked for upload", compressed_path);

	char *compress_args[] = {aa_bin, "archive", "-i", trace_state->trace_filename, "-d", (char *)dt_tmpdir(), "-o", compressed_path, NULL};
	pid_t aa_pid = dt_launch_tool_pipe(compress_args, false, NULL,
	    ^bool (__unused char *data, __unused size_t data_size, __unused dt_pipe_data_handler_context_t *context) {
		T_LOG("🖊️ [aa] %s", data);
		return false;
	},
	    ^bool (char *data, __unused size_t data_size, __unused dt_pipe_data_handler_context_t *context) {
		T_LOG("🖊️ [aa] Error/debug msg: %s", data);
		return false;
	},
	    BUFFER_PATTERN_LINE, NULL);
	T_QUIET; T_EXPECT_TRUE(aa_pid, "🖊️ [aa] pid %d", aa_pid);
	int exit_status = 0;
	int signal_num = SIGPIPE;
	ret = dt_waitpid(aa_pid, &exit_status, &signal_num, 0);
	T_QUIET; T_WITH_ERRNO; T_EXPECT_TRUE(ret, "dt_waitpid for aa, exit status %d signal num %d", exit_status, signal_num);

	/* Lax permissions in case a user wants to open the compressed file without sudo */
	ret = chmod(compressed_path, 0666);
	T_QUIET; T_WITH_ERRNO; T_EXPECT_POSIX_ZERO(ret, "chmod");

	T_LOG("🖊️ Finished saving trace (%s), which is available compressed at \"%s\"",
	    trace_state->short_name, compressed_path);

	trace_state->status = SAVED;
}

void
discard_collected_trace(trace_handle_t handle)
{
	if (!sched_utils_tracing_supported() || !tracing_enabled || trace_save_requested) {
		return;
	}

	int ret;
	struct trace_handle *trace_state = (struct trace_handle *)handle;
	T_QUIET; T_EXPECT_TRUE(trace_state->status == ENDED || trace_state->status == SAVED,
	    "trace was ended or saved");

	/* Delete trace file in order to reclaim disk space on the test device */
	ret = remove(trace_state->abs_filename);
	T_QUIET; T_WITH_ERRNO; T_EXPECT_POSIX_SUCCESS(ret, "remove trace file");

	if (trace_state->status == ENDED) {
		T_LOG("🖊️ Deleted recorded trace file at \"%s\"", trace_state->abs_filename);
	}
	trace_state->status = DISCARDED;
}

void
sched_kdebug_test_fail(uint64_t arg0, uint64_t arg1, uint64_t arg2, uint64_t arg3)
{
	kdebug_trace(ARIADNEDBG_CODE(0, 0), arg0, arg1, arg2, arg3);
}