[apple/xnu.git] / osfmk / kern / bsd_kern.c

/*
 * Copyright (c) 2000-2010 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
#include <mach/mach_types.h>
#include <mach/machine/vm_param.h>
#include <mach/task.h>

#include <kern/kern_types.h>
#include <kern/ledger.h>
#include <kern/processor.h>
#include <kern/thread.h>
#include <kern/task.h>
#include <kern/spl.h>
#include <kern/ast.h>
#include <ipc/ipc_port.h>
#include <ipc/ipc_object.h>
#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <vm/pmap.h>
#include <vm/vm_protos.h> /* last */
#include <sys/resource.h>
#include <sys/signal.h>

#undef thread_should_halt

/* BSD KERN COMPONENT INTERFACE */

task_t  bsd_init_task = TASK_NULL;
boolean_t init_task_died;
extern unsigned int not_in_kdp; /* Skip acquiring locks if we're in kdp */
 
thread_t get_firstthread(task_t);
int get_task_userstop(task_t);
int get_thread_userstop(thread_t);
boolean_t current_thread_aborted(void);
void task_act_iterate_wth_args(task_t, void(*)(thread_t, void *), void *);
kern_return_t get_signalact(task_t , thread_t *, int);
int get_vmsubmap_entries(vm_map_t, vm_object_offset_t, vm_object_offset_t);
int fill_task_rusage(task_t task, rusage_info_current *ri);
int fill_task_io_rusage(task_t task, rusage_info_current *ri);
int fill_task_qos_rusage(task_t task, rusage_info_current *ri);
void fill_task_billed_usage(task_t task, rusage_info_current *ri);
void task_bsdtask_kill(task_t);

#if MACH_BSD
extern void psignal(void *, int);
#endif

/*
 *
 */
void  *get_bsdtask_info(task_t t)
{
        return(t->bsd_info);
}

void task_bsdtask_kill(task_t t)
{
        void * bsd_info = get_bsdtask_info(t);
        if (bsd_info != NULL) {
                psignal(bsd_info, SIGKILL);
        }
}
/*
 *
 */
void *get_bsdthreadtask_info(thread_t th)
{
        return(th->task != TASK_NULL ? th->task->bsd_info : NULL);
}

/*
 *
 */
void set_bsdtask_info(task_t t,void * v)
{
        t->bsd_info=v;
}

/*
 *
 */
void *get_bsdthread_info(thread_t th)
{
        return(th->uthread);
}

/*
 * XXX
 */
int get_thread_lock_count(thread_t th);         /* forced forward */
int get_thread_lock_count(thread_t th)
{
        return(th->mutex_count);
}

/*
 * XXX: wait for BSD to  fix signal code
 * Until then, we cannot block here.  We know the task
 * can't go away, so we make sure it is still active after
 * retrieving the first thread for extra safety.
 */
thread_t get_firstthread(task_t task)
{
        thread_t        thread = (thread_t)(void *)queue_first(&task->threads);

        if (queue_end(&task->threads, (queue_entry_t)thread))
                thread = THREAD_NULL;

        if (!task->active)
                return (THREAD_NULL);

        return (thread);
}

kern_return_t
get_signalact(
        task_t          task,
        thread_t        *result_out,
        int                     setast)
{
        kern_return_t   result = KERN_SUCCESS;
        thread_t                inc, thread = THREAD_NULL;

        task_lock(task);

        if (!task->active) {
                task_unlock(task);

                return (KERN_FAILURE);
        }

        for (inc  = (thread_t)(void *)queue_first(&task->threads);
                        !queue_end(&task->threads, (queue_entry_t)inc); ) {
                thread_mtx_lock(inc);
                if (inc->active &&
                                (inc->sched_flags & TH_SFLAG_ABORTED_MASK) != TH_SFLAG_ABORT) {
                        thread = inc;
                        break;
                }
                thread_mtx_unlock(inc);

                inc = (thread_t)(void *)queue_next(&inc->task_threads);
        }

        if (result_out) 
                *result_out = thread;

        if (thread) {
                if (setast)
                        act_set_astbsd(thread);

                thread_mtx_unlock(thread);
        }
        else
                result = KERN_FAILURE;

        task_unlock(task);

        return (result);
}


kern_return_t
check_actforsig(
        task_t                  task,
        thread_t                thread,
        int                             setast)
{
        kern_return_t   result = KERN_FAILURE;
        thread_t                inc;

        task_lock(task);

        if (!task->active) {
                task_unlock(task);

                return (KERN_FAILURE);
        }

        for (inc  = (thread_t)(void *)queue_first(&task->threads);
                        !queue_end(&task->threads, (queue_entry_t)inc); ) {
                if (inc == thread) {
                        thread_mtx_lock(inc);

                        if (inc->active  && 
                                        (inc->sched_flags & TH_SFLAG_ABORTED_MASK) != TH_SFLAG_ABORT) {
                                result = KERN_SUCCESS;
                                break;
                        }

                        thread_mtx_unlock(inc);
                        break;
                }

                inc = (thread_t)(void *)queue_next(&inc->task_threads);
        }

        if (result == KERN_SUCCESS) {
                if (setast)
                        act_set_astbsd(thread);

                thread_mtx_unlock(thread);
        }

        task_unlock(task);

        return (result);
}

ledger_t  get_task_ledger(task_t t)
{
        return(t->ledger);
}

/*
 * This is only safe to call from a thread executing in
 * in the task's context or if the task is locked. Otherwise,
 * the map could be switched for the task (and freed) before
 * we go to return it here.
 */
vm_map_t  get_task_map(task_t t)
{
        return(t->map);
}

vm_map_t  get_task_map_reference(task_t t)
{
        vm_map_t m;

        if (t == NULL)
                return VM_MAP_NULL;

        task_lock(t);
        if (!t->active) {
                task_unlock(t);
                return VM_MAP_NULL;
        }
        m = t->map;
        vm_map_reference_swap(m);
        task_unlock(t);
        return m;
}

/*
 *
 */
ipc_space_t  get_task_ipcspace(task_t t)
{
        return(t->itk_space);
}

int get_task_numactivethreads(task_t task)
{
        thread_t        inc;
        int num_active_thr=0;
        task_lock(task);

        for (inc  = (thread_t)(void *)queue_first(&task->threads);
                        !queue_end(&task->threads, (queue_entry_t)inc); inc = (thread_t)(void *)queue_next(&inc->task_threads)) 
        {
                if(inc->active)
                        num_active_thr++;
        }
        task_unlock(task);
        return num_active_thr;
}

int  get_task_numacts(task_t t)
{
        return(t->thread_count);
}

/* does this machine need  64bit register set for signal handler */
int is_64signalregset(void)
{
        if (task_has_64BitData(current_task())) {
                return(1);
        }

        return(0);
}

/*
 * Swap in a new map for the task/thread pair; the old map reference is
 * returned.
 */
vm_map_t
swap_task_map(task_t task, thread_t thread, vm_map_t map, boolean_t doswitch)
{
        vm_map_t old_map;

        if (task != thread->task)
                panic("swap_task_map");

        task_lock(task);
        mp_disable_preemption();
        old_map = task->map;
        thread->map = task->map = map;
        if (doswitch) {
                pmap_switch(map->pmap);
        }
        mp_enable_preemption();
        task_unlock(task);

#if (defined(__i386__) || defined(__x86_64__)) && NCOPY_WINDOWS > 0
        inval_copy_windows(thread);
#endif

        return old_map;
}

/*
 *
 * This is only safe to call from a thread executing in
 * in the task's context or if the task is locked. Otherwise,
 * the map could be switched for the task (and freed) before
 * we go to return it here.
 */
pmap_t  get_task_pmap(task_t t)
{
        return(t->map->pmap);
}

/*
 *
 */
uint64_t get_task_resident_size(task_t task) 
{
        vm_map_t map;
        
        map = (task == kernel_task) ? kernel_map: task->map;
        return((uint64_t)pmap_resident_count(map->pmap) * PAGE_SIZE_64);
}

uint64_t get_task_compressed(task_t task) 
{
        vm_map_t map;
        
        map = (task == kernel_task) ? kernel_map: task->map;
        return((uint64_t)pmap_compressed(map->pmap) * PAGE_SIZE_64);
}

uint64_t get_task_resident_max(task_t task) 
{
        vm_map_t map;
        
        map = (task == kernel_task) ? kernel_map: task->map;
        return((uint64_t)pmap_resident_max(map->pmap) * PAGE_SIZE_64);
}

uint64_t get_task_purgeable_size(task_t task) 
{
        kern_return_t ret;
        ledger_amount_t credit, debit;
        uint64_t volatile_size = 0;

        ret = ledger_get_entries(task->ledger, task_ledgers.purgeable_volatile, &credit, &debit);
        if (ret != KERN_SUCCESS) {
                return 0;
        }

        volatile_size += (credit - debit);

        ret = ledger_get_entries(task->ledger, task_ledgers.purgeable_volatile_compressed, &credit, &debit);
        if (ret != KERN_SUCCESS) {
                return 0;
        }

        volatile_size += (credit - debit);

        return volatile_size;
}

/*
 *
 */
uint64_t get_task_phys_footprint(task_t task) 
{       
        kern_return_t ret;
        ledger_amount_t credit, debit;
        
        ret = ledger_get_entries(task->ledger, task_ledgers.phys_footprint, &credit, &debit);
        if (KERN_SUCCESS == ret) {
                return (credit - debit);
        }

        return 0;
}

/*
 *
 */
uint64_t get_task_phys_footprint_max(task_t task) 
{       
        kern_return_t ret;
        ledger_amount_t max;
        
        ret = ledger_get_maximum(task->ledger, task_ledgers.phys_footprint, &max);
        if (KERN_SUCCESS == ret) {
                return max;
        }

        return 0;
}

uint64_t get_task_cpu_time(task_t task)
{
        kern_return_t ret;
        ledger_amount_t credit, debit;
        
        ret = ledger_get_entries(task->ledger, task_ledgers.cpu_time, &credit, &debit);
        if (KERN_SUCCESS == ret) {
                return (credit - debit);
        }

        return 0;
}

/*
 *
 */
task_t  get_threadtask(thread_t th)
{
        return(th->task);
}

/*
 *
 */
vm_map_offset_t
get_map_min(
        vm_map_t        map)
{
        return(vm_map_min(map));
}

/*
 *
 */
vm_map_offset_t
get_map_max(
        vm_map_t        map)
{
        return(vm_map_max(map));
}
vm_map_size_t
get_vmmap_size(
        vm_map_t        map)
{
        return(map->size);
}

int
get_vmsubmap_entries(
        vm_map_t        map,
        vm_object_offset_t      start,
        vm_object_offset_t      end)
{
        int     total_entries = 0;
        vm_map_entry_t  entry;

        if (not_in_kdp)
          vm_map_lock(map);
        entry = vm_map_first_entry(map);
        while((entry != vm_map_to_entry(map)) && (entry->vme_start < start)) {
                entry = entry->vme_next;
        }

        while((entry != vm_map_to_entry(map)) && (entry->vme_start < end)) {
                if(entry->is_sub_map) {
                        total_entries +=        
                                get_vmsubmap_entries(VME_SUBMAP(entry), 
                                                     VME_OFFSET(entry), 
                                                     (VME_OFFSET(entry) + 
                                                      entry->vme_end -
                                                      entry->vme_start));
                } else {
                        total_entries += 1;
                }
                entry = entry->vme_next;
        }
        if (not_in_kdp)
          vm_map_unlock(map);
        return(total_entries);
}

int
get_vmmap_entries(
        vm_map_t        map)
{
        int     total_entries = 0;
        vm_map_entry_t  entry;

        if (not_in_kdp)
          vm_map_lock(map);
        entry = vm_map_first_entry(map);

        while(entry != vm_map_to_entry(map)) {
                if(entry->is_sub_map) {
                        total_entries +=        
                                get_vmsubmap_entries(VME_SUBMAP(entry), 
                                                     VME_OFFSET(entry),
                                                     (VME_OFFSET(entry) + 
                                                      entry->vme_end -
                                                      entry->vme_start));
                } else {
                        total_entries += 1;
                }
                entry = entry->vme_next;
        }
        if (not_in_kdp)
          vm_map_unlock(map);
        return(total_entries);
}

/*
 *
 */
/*
 *
 */
int
get_task_userstop(
        task_t task)
{
        return(task->user_stop_count);
}

/*
 *
 */
int
get_thread_userstop(
        thread_t th)
{
        return(th->user_stop_count);
}

/*
 *
 */
boolean_t
get_task_pidsuspended(
        task_t task)
{
    return (task->pidsuspended);
}

/*
 *
 */
boolean_t 
get_task_frozen(
        task_t task)
{
    return (task->frozen);   
}

/*
 *
 */
boolean_t
thread_should_abort(
        thread_t th)
{
        return ((th->sched_flags & TH_SFLAG_ABORTED_MASK) == TH_SFLAG_ABORT);
}

/*
 * This routine is like thread_should_abort() above.  It checks to
 * see if the current thread is aborted.  But unlike above, it also
 * checks to see if thread is safely aborted.  If so, it returns
 * that fact, and clears the condition (safe aborts only should
 * have a single effect, and a poll of the abort status
 * qualifies.
 */
boolean_t
current_thread_aborted (
                void)
{
        thread_t th = current_thread();
        spl_t s;

        if ((th->sched_flags & TH_SFLAG_ABORTED_MASK) == TH_SFLAG_ABORT &&
                        (th->options & TH_OPT_INTMASK) != THREAD_UNINT)
                return (TRUE);
        if (th->sched_flags & TH_SFLAG_ABORTSAFELY) {
                s = splsched();
                thread_lock(th);
                if (th->sched_flags & TH_SFLAG_ABORTSAFELY)
                        th->sched_flags &= ~TH_SFLAG_ABORTED_MASK;
                thread_unlock(th);
                splx(s);
        }
        return FALSE;
}

/*
 *
 */
void
task_act_iterate_wth_args(
        task_t                  task,
        void                    (*func_callback)(thread_t, void *),
        void                    *func_arg)
{
        thread_t        inc;

        task_lock(task);

        for (inc  = (thread_t)(void *)queue_first(&task->threads);
                        !queue_end(&task->threads, (queue_entry_t)inc); ) {
                (void) (*func_callback)(inc, func_arg);
                inc = (thread_t)(void *)queue_next(&inc->task_threads);
        }

        task_unlock(task);
}


#include <sys/bsdtask_info.h>

void
fill_taskprocinfo(task_t task, struct proc_taskinfo_internal * ptinfo)
{
        vm_map_t map;
        task_absolutetime_info_data_t   tinfo;
        thread_t thread;
        uint32_t cswitch = 0, numrunning = 0;
        uint32_t syscalls_unix = 0;
        uint32_t syscalls_mach = 0;

        task_lock(task);

        map = (task == kernel_task)? kernel_map: task->map;

        ptinfo->pti_virtual_size  = map->size;
        ptinfo->pti_resident_size =
                (mach_vm_size_t)(pmap_resident_count(map->pmap))
                * PAGE_SIZE_64;

        ptinfo->pti_policy = ((task != kernel_task)?
                                          POLICY_TIMESHARE: POLICY_RR);

        tinfo.threads_user = tinfo.threads_system = 0;
        tinfo.total_user = task->total_user_time;
        tinfo.total_system = task->total_system_time;

        queue_iterate(&task->threads, thread, thread_t, task_threads) {
                uint64_t    tval;
                spl_t x;

                if (thread->options & TH_OPT_IDLE_THREAD)
                        continue;

                x = splsched();
                thread_lock(thread);

                if ((thread->state & TH_RUN) == TH_RUN)
                        numrunning++;
                cswitch += thread->c_switch;
                tval = timer_grab(&thread->user_timer);
                tinfo.threads_user += tval;
                tinfo.total_user += tval;

                tval = timer_grab(&thread->system_timer);

                if (thread->precise_user_kernel_time) {
                        tinfo.threads_system += tval;
                        tinfo.total_system += tval;
                } else {
                        /* system_timer may represent either sys or user */
                        tinfo.threads_user += tval;
                        tinfo.total_user += tval;
                }

                syscalls_unix += thread->syscalls_unix;
                syscalls_mach += thread->syscalls_mach;

                thread_unlock(thread);
                splx(x);
        }

        ptinfo->pti_total_system = tinfo.total_system;
        ptinfo->pti_total_user = tinfo.total_user;
        ptinfo->pti_threads_system = tinfo.threads_system;
        ptinfo->pti_threads_user = tinfo.threads_user;
        
        ptinfo->pti_faults = task->faults;
        ptinfo->pti_pageins = task->pageins;
        ptinfo->pti_cow_faults = task->cow_faults;
        ptinfo->pti_messages_sent = task->messages_sent;
        ptinfo->pti_messages_received = task->messages_received;
        ptinfo->pti_syscalls_mach = task->syscalls_mach + syscalls_mach;
        ptinfo->pti_syscalls_unix = task->syscalls_unix + syscalls_unix;
        ptinfo->pti_csw = task->c_switch + cswitch;
        ptinfo->pti_threadnum = task->thread_count;
        ptinfo->pti_numrunning = numrunning;
        ptinfo->pti_priority = task->priority;

        task_unlock(task);
}

int 
fill_taskthreadinfo(task_t task, uint64_t thaddr, int thuniqueid, struct proc_threadinfo_internal * ptinfo, void * vpp, int *vidp)
{
        thread_t  thact;
        int err=0;
        mach_msg_type_number_t count;
        thread_basic_info_data_t basic_info;
        kern_return_t kret;
        uint64_t addr = 0;

        task_lock(task);

        for (thact  = (thread_t)(void *)queue_first(&task->threads);
                        !queue_end(&task->threads, (queue_entry_t)thact); ) {
                addr = (thuniqueid==0)?thact->machine.cthread_self: thact->thread_id;
                if (addr == thaddr)
                {
                
                        count = THREAD_BASIC_INFO_COUNT;
                        if ((kret = thread_info_internal(thact, THREAD_BASIC_INFO, (thread_info_t)&basic_info, &count)) != KERN_SUCCESS) {
                                err = 1;
                                goto out;       
                        }
                        ptinfo->pth_user_time = ((basic_info.user_time.seconds * (integer_t)NSEC_PER_SEC) + (basic_info.user_time.microseconds * (integer_t)NSEC_PER_USEC));
                        ptinfo->pth_system_time = ((basic_info.system_time.seconds * (integer_t)NSEC_PER_SEC) + (basic_info.system_time.microseconds * (integer_t)NSEC_PER_USEC));

                        ptinfo->pth_cpu_usage = basic_info.cpu_usage;
                        ptinfo->pth_policy = basic_info.policy;
                        ptinfo->pth_run_state = basic_info.run_state;
                        ptinfo->pth_flags = basic_info.flags;
                        ptinfo->pth_sleep_time = basic_info.sleep_time;
                        ptinfo->pth_curpri = thact->sched_pri;
                        ptinfo->pth_priority = thact->base_pri;
                        ptinfo->pth_maxpriority = thact->max_priority;
                        
                        if ((vpp != NULL) && (thact->uthread != NULL)) 
                                bsd_threadcdir(thact->uthread, vpp, vidp);
                        bsd_getthreadname(thact->uthread,ptinfo->pth_name);
                        err = 0;
                        goto out; 
                }
                thact = (thread_t)(void *)queue_next(&thact->task_threads);
        }
        err = 1;

out:
        task_unlock(task);
        return(err);
}

int
fill_taskthreadlist(task_t task, void * buffer, int thcount)
{
        int numthr=0;
        thread_t thact;
        uint64_t * uptr;
        uint64_t  thaddr;

        uptr = (uint64_t *)buffer;

        task_lock(task);

        for (thact  = (thread_t)(void *)queue_first(&task->threads);
                        !queue_end(&task->threads, (queue_entry_t)thact); ) {
                thaddr = thact->machine.cthread_self;
                *uptr++ = thaddr;
                numthr++;
                if (numthr >= thcount)
                        goto out;
                thact = (thread_t)(void *)queue_next(&thact->task_threads);
        }

out:
        task_unlock(task);
        return (int)(numthr * sizeof(uint64_t));
        
}

int
get_numthreads(task_t task)
{
        return(task->thread_count);
}

/*
 * Gather the various pieces of info about the designated task, 
 * and collect it all into a single rusage_info.
 */
int
fill_task_rusage(task_t task, rusage_info_current *ri)
{
        struct task_power_info powerinfo;

        assert(task != TASK_NULL);
        task_lock(task);

        task_power_info_locked(task, &powerinfo, NULL);
        ri->ri_pkg_idle_wkups = powerinfo.task_platform_idle_wakeups;
        ri->ri_interrupt_wkups = powerinfo.task_interrupt_wakeups;
        ri->ri_user_time = powerinfo.total_user;
        ri->ri_system_time = powerinfo.total_system;

        ledger_get_balance(task->ledger, task_ledgers.phys_footprint,
                           (ledger_amount_t *)&ri->ri_phys_footprint);
        ledger_get_balance(task->ledger, task_ledgers.phys_mem,
                           (ledger_amount_t *)&ri->ri_resident_size);
        ledger_get_balance(task->ledger, task_ledgers.wired_mem,
                           (ledger_amount_t *)&ri->ri_wired_size);

        ri->ri_pageins = task->pageins;

        task_unlock(task);
        return (0);
}

void
fill_task_billed_usage(task_t task __unused, rusage_info_current *ri)
{
#if CONFIG_BANK
        ri->ri_billed_system_time = bank_billed_time(task->bank_context);
        ri->ri_serviced_system_time = bank_serviced_time(task->bank_context);
#else
        ri->ri_billed_system_time = 0;
        ri->ri_serviced_system_time = 0;
#endif
}

int
fill_task_io_rusage(task_t task, rusage_info_current *ri)
{
        assert(task != TASK_NULL);
        task_lock(task);

        if (task->task_io_stats) {
                ri->ri_diskio_bytesread = task->task_io_stats->disk_reads.size;
                ri->ri_diskio_byteswritten = (task->task_io_stats->total_io.size - task->task_io_stats->disk_reads.size);
        } else {
                /* I/O Stats unavailable */
                ri->ri_diskio_bytesread = 0;
                ri->ri_diskio_byteswritten = 0;
        }
        task_unlock(task);
        return (0);
}

int
fill_task_qos_rusage(task_t task, rusage_info_current *ri)
{
        thread_t thread;

        assert(task != TASK_NULL);
        task_lock(task);

        /* Rollup Qos time of all the threads to task */
        queue_iterate(&task->threads, thread, thread_t, task_threads) {
                if (thread->options & TH_OPT_IDLE_THREAD)
                        continue;

                thread_mtx_lock(thread);
                thread_update_qos_cpu_time(thread, TRUE);
                thread_mtx_unlock(thread);
                
        }
        ri->ri_cpu_time_qos_default = task->cpu_time_qos_stats.cpu_time_qos_default;
        ri->ri_cpu_time_qos_maintenance = task->cpu_time_qos_stats.cpu_time_qos_maintenance;
        ri->ri_cpu_time_qos_background = task->cpu_time_qos_stats.cpu_time_qos_background;
        ri->ri_cpu_time_qos_utility = task->cpu_time_qos_stats.cpu_time_qos_utility;
        ri->ri_cpu_time_qos_legacy = task->cpu_time_qos_stats.cpu_time_qos_legacy;
        ri->ri_cpu_time_qos_user_initiated = task->cpu_time_qos_stats.cpu_time_qos_user_initiated;
        ri->ri_cpu_time_qos_user_interactive = task->cpu_time_qos_stats.cpu_time_qos_user_interactive;

        task_unlock(task);
        return (0);
}