6 files changed, 504 insertions, 61 deletions

diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 298c9276dfdb..2bdcdc3691e5 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -542,7 +542,7 @@ static void print_lock(struct held_lock *hlock)
         print_ip_sym(hlock->acquire_ip);
 }
 
-static void lockdep_print_held_locks(struct task_struct *curr)
+void lockdep_print_held_locks(struct task_struct *curr)
 {
         int i, depth = curr->lockdep_depth;
 
@@ -558,6 +558,7 @@ static void lockdep_print_held_locks(struct task_struct *curr)
                 print_lock(curr->held_locks + i);
         }
 }
+EXPORT_SYMBOL(lockdep_print_held_locks);
 
 static void print_kernel_version(void)
 {
@@ -583,6 +584,10 @@ static int static_obj(void *obj)
                       end   = (unsigned long) &_end,
                       addr  = (unsigned long) obj;
 
+        // GLENN
+        return 1;
+
+
         /*
          * static variable?
          */
diff --git a/kernel/mutex.c b/kernel/mutex.c
index d607ed5dd441..2f363b9bfc1f 100644
--- a/kernel/mutex.c
+++ b/kernel/mutex.c
@@ -498,3 +498,128 @@ int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock)
         return 1;
 }
 EXPORT_SYMBOL(atomic_dec_and_mutex_lock);
+
+
+
+
+void mutex_lock_sfx(struct mutex *lock,
+                                   side_effect_t pre, unsigned long pre_arg,
+                                   side_effect_t post, unsigned long post_arg)
+{
+        long state = TASK_UNINTERRUPTIBLE;
+
+        struct task_struct *task = current;
+        struct mutex_waiter waiter;
+        unsigned long flags;
+        
+        preempt_disable();
+        mutex_acquire(&lock->dep_map, subclass, 0, ip);
+
+        spin_lock_mutex(&lock->wait_lock, flags);
+        
+        if(pre)
+        {
+                if(unlikely(pre(pre_arg)))
+                {
+                        // this will fuck with lockdep's CONFIG_PROVE_LOCKING...
+                        spin_unlock_mutex(&lock->wait_lock, flags);
+                        preempt_enable();
+                        return;
+                }
+        }
+
+        debug_mutex_lock_common(lock, &waiter);
+        debug_mutex_add_waiter(lock, &waiter, task_thread_info(task));
+        
+        /* add waiting tasks to the end of the waitqueue (FIFO): */
+        list_add_tail(&waiter.list, &lock->wait_list);
+        waiter.task = task;
+        
+        if (atomic_xchg(&lock->count, -1) == 1)
+                goto done;
+        
+        lock_contended(&lock->dep_map, ip);
+        
+        for (;;) {
+                /*
+                 * Lets try to take the lock again - this is needed even if
+                 * we get here for the first time (shortly after failing to
+                 * acquire the lock), to make sure that we get a wakeup once
+                 * it's unlocked. Later on, if we sleep, this is the
+                 * operation that gives us the lock. We xchg it to -1, so
+                 * that when we release the lock, we properly wake up the
+                 * other waiters:
+                 */
+                if (atomic_xchg(&lock->count, -1) == 1)
+                        break;
+                
+                __set_task_state(task, state);
+                
+                /* didnt get the lock, go to sleep: */
+                spin_unlock_mutex(&lock->wait_lock, flags);
+                preempt_enable_no_resched();
+                schedule();
+                preempt_disable();
+                spin_lock_mutex(&lock->wait_lock, flags);
+        }
+        
+done:
+        lock_acquired(&lock->dep_map, ip);
+        /* got the lock - rejoice! */
+        mutex_remove_waiter(lock, &waiter, current_thread_info());
+        mutex_set_owner(lock);
+        
+        /* set it to 0 if there are no waiters left: */
+        if (likely(list_empty(&lock->wait_list)))
+                atomic_set(&lock->count, 0);
+        
+        if(post)
+                post(post_arg); 
+        
+        spin_unlock_mutex(&lock->wait_lock, flags);
+        
+        debug_mutex_free_waiter(&waiter);
+        preempt_enable();
+}
+EXPORT_SYMBOL(mutex_lock_sfx);
+
+void mutex_unlock_sfx(struct mutex *lock,
+                                        side_effect_t pre, unsigned long pre_arg,
+                                        side_effect_t post, unsigned long post_arg)
+{
+        unsigned long flags;
+        
+        spin_lock_mutex(&lock->wait_lock, flags);
+        
+        if(pre)
+                pre(pre_arg);
+        
+        //mutex_release(&lock->dep_map, nested, _RET_IP_);
+        mutex_release(&lock->dep_map, 1, _RET_IP_);
+        debug_mutex_unlock(lock);
+        
+        /*
+         * some architectures leave the lock unlocked in the fastpath failure
+         * case, others need to leave it locked. In the later case we have to
+         * unlock it here
+         */
+        if (__mutex_slowpath_needs_to_unlock())
+                atomic_set(&lock->count, 1);
+        
+        if (!list_empty(&lock->wait_list)) {
+                /* get the first entry from the wait-list: */
+                struct mutex_waiter *waiter =
+                list_entry(lock->wait_list.next,
+                                   struct mutex_waiter, list);
+                
+                debug_mutex_wake_waiter(lock, waiter);
+                
+                wake_up_process(waiter->task);
+        }
+        
+        if(post)
+                post(post_arg);
+        
+        spin_unlock_mutex(&lock->wait_lock, flags);     
+}
+EXPORT_SYMBOL(mutex_unlock_sfx);
diff --git a/kernel/sched.c b/kernel/sched.c
index baaca61bc3a3..f3d9a69a3777 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -83,6 +83,10 @@
 #include <litmus/sched_trace.h>
 #include <litmus/trace.h>
 
+#ifdef CONFIG_LITMUS_SOFTIRQD
+#include <litmus/litmus_softirq.h>
+#endif
+
 static void litmus_tick(struct rq*, struct task_struct*);
 
 #define CREATE_TRACE_POINTS
@@ -4305,6 +4309,7 @@ pick_next_task(struct rq *rq)
         BUG(); /* the idle class will always have a runnable task */
 }
 
+
 /*
  * schedule() is the main scheduler function.
  */
@@ -4323,6 +4328,10 @@ need_resched:
         rcu_note_context_switch(cpu);
         prev = rq->curr;
 
+#ifdef CONFIG_LITMUS_SOFTIRQD
+        release_klitirqd_lock(prev);
+#endif
+
         /* LITMUS^RT: quickly re-evaluate the scheduling decision
          * if the previous one is no longer valid after CTX.
          */
@@ -4411,13 +4420,24 @@ litmus_need_resched_nonpreemptible:
                 goto litmus_need_resched_nonpreemptible;
 
         preempt_enable_no_resched();
+
         if (need_resched())
                 goto need_resched;
 
+#ifdef LITMUS_SOFTIRQD
+        reacquire_klitirqd_lock(prev);
+#endif
+
+#ifdef CONFIG_LITMUS_PAI_SOFTIRQD
+        litmus->run_tasklets(prev);
+#endif  
+        
         srp_ceiling_block();
 }
 EXPORT_SYMBOL(schedule);
 
+
+
 #ifdef CONFIG_MUTEX_SPIN_ON_OWNER
 
 static inline bool owner_running(struct mutex *lock, struct task_struct *owner)
@@ -4561,6 +4581,7 @@ static void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
         }
 }
 
+
 /**
  * __wake_up - wake up threads blocked on a waitqueue.
  * @q: the waitqueue
@@ -4747,6 +4768,12 @@ void __sched wait_for_completion(struct completion *x)
 }
 EXPORT_SYMBOL(wait_for_completion);
 
+void __sched __wait_for_completion_locked(struct completion *x)
+{
+        do_wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(__wait_for_completion_locked);
+
 /**
  * wait_for_completion_timeout: - waits for completion of a task (w/timeout)
  * @x:  holds the state of this particular completion
diff --git a/kernel/semaphore.c b/kernel/semaphore.c
index 94a62c0d4ade..c947a046a6d7 100644
--- a/kernel/semaphore.c
+++ b/kernel/semaphore.c
@@ -33,11 +33,11 @@
 #include <linux/spinlock.h>
 #include <linux/ftrace.h>
 
-static noinline void __down(struct semaphore *sem);
+noinline void __down(struct semaphore *sem);
 static noinline int __down_interruptible(struct semaphore *sem);
 static noinline int __down_killable(struct semaphore *sem);
 static noinline int __down_timeout(struct semaphore *sem, long jiffies);
-static noinline void __up(struct semaphore *sem);
+noinline void __up(struct semaphore *sem);
 
 /**
  * down - acquire the semaphore
@@ -190,11 +190,13 @@ EXPORT_SYMBOL(up);
 
 /* Functions for the contended case */
 
+/*
 struct semaphore_waiter {
         struct list_head list;
         struct task_struct *task;
         int up;
 };
+ */
 
 /*
  * Because this function is inlined, the 'state' parameter will be
@@ -233,10 +235,12 @@ static inline int __sched __down_common(struct semaphore *sem, long state,
         return -EINTR;
 }
 
-static noinline void __sched __down(struct semaphore *sem)
+noinline void __sched __down(struct semaphore *sem)
 {
         __down_common(sem, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
 }
+EXPORT_SYMBOL(__down);
+
 
 static noinline int __sched __down_interruptible(struct semaphore *sem)
 {
@@ -253,7 +257,7 @@ static noinline int __sched __down_timeout(struct semaphore *sem, long jiffies)
         return __down_common(sem, TASK_UNINTERRUPTIBLE, jiffies);
 }
 
-static noinline void __sched __up(struct semaphore *sem)
+noinline void __sched __up(struct semaphore *sem)
 {
         struct semaphore_waiter *waiter = list_first_entry(&sem->wait_list,
                                                 struct semaphore_waiter, list);
@@ -261,3 +265,4 @@ static noinline void __sched __up(struct semaphore *sem)
         waiter->up = 1;
         wake_up_process(waiter->task);
 }
+EXPORT_SYMBOL(__up);
\ No newline at end of file
diff --git a/kernel/softirq.c b/kernel/softirq.c
index fca82c32042b..5ce271675662 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -29,6 +29,15 @@
 #include <trace/events/irq.h>
 
 #include <asm/irq.h>
+
+#include <litmus/litmus.h>
+#include <litmus/sched_trace.h>
+
+#ifdef CONFIG_LITMUS_NVIDIA
+#include <litmus/nvidia_info.h>
+#include <litmus/trace.h>
+#endif
+
 /*
    - No shared variables, all the data are CPU local.
    - If a softirq needs serialization, let it serialize itself
@@ -67,7 +76,7 @@ char *softirq_to_name[NR_SOFTIRQS] = {
  * to the pending events, so lets the scheduler to balance
  * the softirq load for us.
  */
-static void wakeup_softirqd(void)
+void wakeup_softirqd(void)
 {
         /* Interrupts are disabled: no need to stop preemption */
         struct task_struct *tsk = __this_cpu_read(ksoftirqd);
@@ -193,6 +202,7 @@ void local_bh_enable_ip(unsigned long ip)
 }
 EXPORT_SYMBOL(local_bh_enable_ip);
 
+
 /*
  * We restart softirq processing MAX_SOFTIRQ_RESTART times,
  * and we fall back to softirqd after that.
@@ -206,65 +216,65 @@ EXPORT_SYMBOL(local_bh_enable_ip);
 
 asmlinkage void __do_softirq(void)
 {
-        struct softirq_action *h;
-        __u32 pending;
-        int max_restart = MAX_SOFTIRQ_RESTART;
-        int cpu;
+    struct softirq_action *h; 
+    __u32 pending;
+    int max_restart = MAX_SOFTIRQ_RESTART;
+    int cpu;
 
-        pending = local_softirq_pending();
-        account_system_vtime(current);
+    pending = local_softirq_pending();
+    account_system_vtime(current);
 
-        __local_bh_disable((unsigned long)__builtin_return_address(0),
-                                SOFTIRQ_OFFSET);
-        lockdep_softirq_enter();
+    __local_bh_disable((unsigned long)__builtin_return_address(0),
+                SOFTIRQ_OFFSET);
+    lockdep_softirq_enter();
 
-        cpu = smp_processor_id();
+    cpu = smp_processor_id();
 restart:
-        /* Reset the pending bitmask before enabling irqs */
-        set_softirq_pending(0);
+    /* Reset the pending bitmask before enabling irqs */
+    set_softirq_pending(0);
 
-        local_irq_enable();
+    local_irq_enable();
 
-        h = softirq_vec;
-
-        do {
-                if (pending & 1) {
-                        unsigned int vec_nr = h - softirq_vec;
-                        int prev_count = preempt_count();
-
-                        kstat_incr_softirqs_this_cpu(vec_nr);
-
-                        trace_softirq_entry(vec_nr);
-                        h->action(h);
-                        trace_softirq_exit(vec_nr);
-                        if (unlikely(prev_count != preempt_count())) {
-                                printk(KERN_ERR "huh, entered softirq %u %s %p"
-                                       "with preempt_count %08x,"
-                                       " exited with %08x?\n", vec_nr,
-                                       softirq_to_name[vec_nr], h->action,
-                                       prev_count, preempt_count());
-                                preempt_count() = prev_count;
-                        }
+    h = softirq_vec;
 
-                        rcu_bh_qs(cpu);
-                }
-                h++;
-                pending >>= 1;
-        } while (pending);
+    do {
+        if (pending & 1) {
+            unsigned int vec_nr = h - softirq_vec;
+            int prev_count = preempt_count();
 
-        local_irq_disable();
+            kstat_incr_softirqs_this_cpu(vec_nr);
 
-        pending = local_softirq_pending();
-        if (pending && --max_restart)
-                goto restart;
+            trace_softirq_entry(vec_nr);
+            h->action(h);
+            trace_softirq_exit(vec_nr);
+            if (unlikely(prev_count != preempt_count())) {
+                printk(KERN_ERR "huh, entered softirq %u %s %p"
+                       "with preempt_count %08x,"
+                       " exited with %08x?\n", vec_nr,
+                       softirq_to_name[vec_nr], h->action,
+                       prev_count, preempt_count());
+                preempt_count() = prev_count;
+            }   
 
-        if (pending)
-                wakeup_softirqd();
+            rcu_bh_qs(cpu);
+        }   
+        h++;
+        pending >>= 1;
+    } while (pending);
 
-        lockdep_softirq_exit();
+    local_irq_disable();
 
-        account_system_vtime(current);
-        __local_bh_enable(SOFTIRQ_OFFSET);
+    pending = local_softirq_pending();
+    if (pending && --max_restart)
+        goto restart;
+
+    if (pending)
+        wakeup_softirqd();
+
+    lockdep_softirq_exit();
+
+    account_system_vtime(current);
+    __local_bh_enable(SOFTIRQ_OFFSET);
 }
 
 #ifndef __ARCH_HAS_DO_SOFTIRQ
@@ -402,8 +412,99 @@ struct tasklet_head
 static DEFINE_PER_CPU(struct tasklet_head, tasklet_vec);
 static DEFINE_PER_CPU(struct tasklet_head, tasklet_hi_vec);
 
+#ifdef CONFIG_LITMUS_NVIDIA
+static int __do_nv_now(struct tasklet_struct* tasklet)
+{
+        int success = 1;
+
+        if(tasklet_trylock(tasklet)) {
+                if (!atomic_read(&tasklet->count)) {
+                        if (!test_and_clear_bit(TASKLET_STATE_SCHED, &tasklet->state)) {    
+                                BUG();
+                        }
+                        tasklet->func(tasklet->data);
+                        tasklet_unlock(tasklet);
+                }
+                else {
+                        success = 0;
+                }
+
+                tasklet_unlock(tasklet);
+        }
+        else {
+                success = 0;
+        }
+
+        return success;
+}
+#endif
+
+
 void __tasklet_schedule(struct tasklet_struct *t)
 {
+#ifdef CONFIG_LITMUS_NVIDIA
+        if(is_nvidia_func(t->func))
+        {
+#if 0
+                // do nvidia tasklets right away and return
+                if(__do_nv_now(t))
+                        return;
+#else
+                u32 nvidia_device = get_tasklet_nv_device_num(t);       
+                //              TRACE("%s: Handling NVIDIA tasklet for device\t%u\tat\t%llu\n",
+                //                        __FUNCTION__, nvidia_device,litmus_clock());
+
+                unsigned long flags;
+                struct task_struct* device_owner;
+
+                lock_nv_registry(nvidia_device, &flags);
+
+                device_owner = get_nv_max_device_owner(nvidia_device);
+
+                if(device_owner==NULL)
+                {
+                        t->owner = NULL;
+                }
+                else
+                {
+                        if(is_realtime(device_owner))
+                        {
+                                TRACE("%s: Handling NVIDIA tasklet for device %u at %llu\n",
+                                          __FUNCTION__, nvidia_device,litmus_clock());                          
+                                TRACE("%s: the owner task %d of NVIDIA Device %u is RT-task\n",
+                                          __FUNCTION__,device_owner->pid,nvidia_device);
+
+                                t->owner = device_owner;
+                                sched_trace_tasklet_release(t->owner);
+
+                                if(likely(_litmus_tasklet_schedule(t,nvidia_device)))
+                                {
+                                        unlock_nv_registry(nvidia_device, &flags);
+                                        return;
+                                }
+                                else
+                                {
+                                        t->owner = NULL; /* fall through to normal scheduling */
+                                }
+                        }
+                        else
+                        {
+                                t->owner = NULL;
+                        }
+                }
+                unlock_nv_registry(nvidia_device, &flags);
+#endif
+        }
+
+#endif
+
+        ___tasklet_schedule(t);
+}
+EXPORT_SYMBOL(__tasklet_schedule);
+
+
+void ___tasklet_schedule(struct tasklet_struct *t)
+{
         unsigned long flags;
 
         local_irq_save(flags);
@@ -413,11 +514,65 @@ void __tasklet_schedule(struct tasklet_struct *t)
         raise_softirq_irqoff(TASKLET_SOFTIRQ);
         local_irq_restore(flags);
 }
+EXPORT_SYMBOL(___tasklet_schedule);
 
-EXPORT_SYMBOL(__tasklet_schedule);
 
 void __tasklet_hi_schedule(struct tasklet_struct *t)
 {
+#ifdef CONFIG_LITMUS_NVIDIA
+        if(is_nvidia_func(t->func))
+        {       
+                u32 nvidia_device = get_tasklet_nv_device_num(t);
+                //              TRACE("%s: Handling NVIDIA tasklet for device\t%u\tat\t%llu\n",
+                //                        __FUNCTION__, nvidia_device,litmus_clock());
+
+                unsigned long flags;
+                struct task_struct* device_owner;
+                
+                lock_nv_registry(nvidia_device, &flags);
+                
+                device_owner = get_nv_max_device_owner(nvidia_device);
+
+                if(device_owner==NULL) 
+                {
+                        t->owner = NULL;
+                }
+                else
+                {
+                        if( is_realtime(device_owner))
+                        {
+                                TRACE("%s: Handling NVIDIA tasklet for device %u\tat %llu\n",
+                                          __FUNCTION__, nvidia_device,litmus_clock());                          
+                                TRACE("%s: the owner task %d of NVIDIA Device %u is RT-task\n",
+                                          __FUNCTION__,device_owner->pid,nvidia_device);
+                                
+                                t->owner = device_owner;
+                                sched_trace_tasklet_release(t->owner);
+                                if(likely(_litmus_tasklet_hi_schedule(t,nvidia_device)))
+                                {
+                                        unlock_nv_registry(nvidia_device, &flags);
+                                        return;
+                                }
+                                else
+                                {
+                                        t->owner = NULL; /* fall through to normal scheduling */
+                                }
+                        }
+                        else
+                        {
+                                t->owner = NULL;
+                        }
+                }
+                unlock_nv_registry(nvidia_device, &flags);
+        }
+#endif
+
+        ___tasklet_hi_schedule(t);
+}
+EXPORT_SYMBOL(__tasklet_hi_schedule);
+
+void ___tasklet_hi_schedule(struct tasklet_struct* t)
+{
         unsigned long flags;
 
         local_irq_save(flags);
@@ -427,19 +582,72 @@ void __tasklet_hi_schedule(struct tasklet_struct *t)
         raise_softirq_irqoff(HI_SOFTIRQ);
         local_irq_restore(flags);
 }
-
-EXPORT_SYMBOL(__tasklet_hi_schedule);
+EXPORT_SYMBOL(___tasklet_hi_schedule);
 
 void __tasklet_hi_schedule_first(struct tasklet_struct *t)
 {
         BUG_ON(!irqs_disabled());
+#ifdef CONFIG_LITMUS_NVIDIA     
+        if(is_nvidia_func(t->func))
+        {       
+                u32 nvidia_device = get_tasklet_nv_device_num(t);
+                //              TRACE("%s: Handling NVIDIA tasklet for device\t%u\tat\t%llu\n",
+                //                        __FUNCTION__, nvidia_device,litmus_clock());
+                unsigned long flags;
+                struct task_struct* device_owner;
+                
+                lock_nv_registry(nvidia_device, &flags);
+
+                device_owner = get_nv_max_device_owner(nvidia_device);
+
+                if(device_owner==NULL)
+                {
+                        t->owner = NULL;
+                }
+                else
+                {
+                        if(is_realtime(device_owner))
+                        {
+                                TRACE("%s: Handling NVIDIA tasklet for device %u at %llu\n",
+                                          __FUNCTION__, nvidia_device,litmus_clock());
+                                
+                                TRACE("%s: the owner task %d of NVIDIA Device %u is RT-task\n",
+                                          __FUNCTION__,device_owner->pid,nvidia_device);
+                                
+                                t->owner = device_owner;
+                                sched_trace_tasklet_release(t->owner);
+                                if(likely(_litmus_tasklet_hi_schedule_first(t,nvidia_device)))
+                                {
+                                        unlock_nv_registry(nvidia_device, &flags);
+                                        return;
+                                }
+                                else
+                                {
+                                        t->owner = NULL; /* fall through to normal scheduling */
+                                }
+                        }
+                        else
+                        {
+                                t->owner = NULL;
+                        }
+                }
+                unlock_nv_registry(nvidia_device, &flags);
+        }
+#endif
+
+        ___tasklet_hi_schedule_first(t);
+}
+EXPORT_SYMBOL(__tasklet_hi_schedule_first);
+
+void ___tasklet_hi_schedule_first(struct tasklet_struct* t)
+{
+        BUG_ON(!irqs_disabled());
 
         t->next = __this_cpu_read(tasklet_hi_vec.head);
         __this_cpu_write(tasklet_hi_vec.head, t);
         __raise_softirq_irqoff(HI_SOFTIRQ);
 }
-
-EXPORT_SYMBOL(__tasklet_hi_schedule_first);
+EXPORT_SYMBOL(___tasklet_hi_schedule_first);
 
 static void tasklet_action(struct softirq_action *a)
 {
@@ -495,6 +703,7 @@ static void tasklet_hi_action(struct softirq_action *a)
                         if (!atomic_read(&t->count)) {
                                 if (!test_and_clear_bit(TASKLET_STATE_SCHED, &t->state))
                                         BUG();
+
                                 t->func(t->data);
                                 tasklet_unlock(t);
                                 continue;
@@ -518,8 +727,13 @@ void tasklet_init(struct tasklet_struct *t,
         t->next = NULL;
         t->state = 0;
         atomic_set(&t->count, 0);
+
         t->func = func;
         t->data = data;
+
+#ifdef CONFIG_LITMUS_SOFTIRQD
+        t->owner = NULL;
+#endif
 }
 
 EXPORT_SYMBOL(tasklet_init);
@@ -534,6 +748,7 @@ void tasklet_kill(struct tasklet_struct *t)
                         yield();
                 } while (test_bit(TASKLET_STATE_SCHED, &t->state));
         }
+
         tasklet_unlock_wait(t);
         clear_bit(TASKLET_STATE_SCHED, &t->state);
 }
@@ -808,6 +1023,7 @@ void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu)
         for (i = &per_cpu(tasklet_vec, cpu).head; *i; i = &(*i)->next) {
                 if (*i == t) {
                         *i = t->next;
+
                         /* If this was the tail element, move the tail ptr */
                         if (*i == NULL)
                                 per_cpu(tasklet_vec, cpu).tail = i;
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 0400553f0d04..6b59d59ce3cf 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -44,6 +44,13 @@
 
 #include "workqueue_sched.h"
 
+#ifdef CONFIG_LITMUS_NVIDIA
+#include <litmus/litmus.h>
+#include <litmus/sched_trace.h>
+#include <litmus/nvidia_info.h>
+#endif
+
+
 enum {
         /* global_cwq flags */
         GCWQ_MANAGE_WORKERS     = 1 << 0,       /* need to manage workers */
@@ -1047,9 +1054,7 @@ static void __queue_work(unsigned int cpu, struct workqueue_struct *wq,
                 work_flags |= WORK_STRUCT_DELAYED;
                 worklist = &cwq->delayed_works;
         }
-
         insert_work(cwq, work, worklist, work_flags);
-
         spin_unlock_irqrestore(&gcwq->lock, flags);
 }
 
@@ -2687,10 +2692,70 @@ EXPORT_SYMBOL(cancel_delayed_work_sync);
  */
 int schedule_work(struct work_struct *work)
 {
-        return queue_work(system_wq, work);
+#if 0
+#if defined(CONFIG_LITMUS_NVIDIA) && defined(CONFIG_LITMUS_SOFTIRQD)
+        if(is_nvidia_func(work->func))
+        {
+                u32 nvidiaDevice = get_work_nv_device_num(work);
+                
+                //1) Ask Litmus which task owns GPU <nvidiaDevice>. (API to be defined.)
+                unsigned long flags;
+                struct task_struct* device_owner;
+                
+                lock_nv_registry(nvidiaDevice, &flags);
+                
+                device_owner = get_nv_max_device_owner(nvidiaDevice);
+                
+                //2) If there is an owner, set work->owner to the owner's task struct.
+                if(device_owner==NULL) 
+                {
+                        work->owner = NULL;
+                        //TRACE("%s: the owner task of NVIDIA Device %u is NULL\n",__FUNCTION__,nvidiaDevice);
+                }
+                else
+                {
+                        if( is_realtime(device_owner))
+                        {
+                                TRACE("%s: Handling NVIDIA work for device\t%u\tat\t%llu\n",
+                                          __FUNCTION__, nvidiaDevice,litmus_clock());
+                                TRACE("%s: the owner task %d of NVIDIA Device %u is RT-task\n",
+                                          __FUNCTION__,
+                                          device_owner->pid,
+                                          nvidiaDevice);
+                                
+                                //3) Call litmus_schedule_work() and return (don't execute the rest
+                                //      of schedule_schedule()).
+                                work->owner = device_owner;
+                                sched_trace_work_release(work->owner);
+                                if(likely(litmus_schedule_work(work, nvidiaDevice)))
+                                {
+                                        unlock_nv_registry(nvidiaDevice, &flags);
+                                        return 1;
+                                }
+                                else
+                                {
+                                        work->owner = NULL; /* fall through to normal work scheduling */
+                                }
+                        }
+                        else
+                        {
+                                work->owner = NULL;
+                        }
+                }
+                unlock_nv_registry(nvidiaDevice, &flags);
+        }
+#endif
+#endif
+        return(__schedule_work(work));
 }
 EXPORT_SYMBOL(schedule_work);
 
+int __schedule_work(struct work_struct* work)
+{
+        return queue_work(system_wq, work);
+}
+EXPORT_SYMBOL(__schedule_work);
+
 /*
  * schedule_work_on - put work task on a specific cpu
  * @cpu: cpu to put the work task on