Merge remote-tracking branch 'github/staging' into wip-2012.3-gpu-stage-merge

6 files changed, 80 insertions, 5 deletions

diff --git a/include/litmus/rt_param.h b/include/litmus/rt_param.h
index de20eff7cf71..8d37d6e050c9 100644
--- a/include/litmus/rt_param.h
+++ b/include/litmus/rt_param.h
@@ -348,6 +348,11 @@ struct rt_param {
         unsigned int            priority_boosted:1;
         /* If so, when did this start? */
         lt_t                    boost_start_time;
+
+        /* How many LITMUS^RT locks does the task currently hold/wait for? */
+        unsigned int            num_locks_held;
+        /* How many PCP/SRP locks does the task currently hold/wait for? */
+        unsigned int            num_local_locks_held;
 #endif
 
         /* user controlled parameters */
diff --git a/litmus/sched_gsn_edf.c b/litmus/sched_gsn_edf.c
index 4589888fc652..46a10fa17044 100644
--- a/litmus/sched_gsn_edf.c
+++ b/litmus/sched_gsn_edf.c
@@ -1569,6 +1569,10 @@ int gsnedf_fmlp_lock(struct litmus_lock* l)
         if (!is_realtime(t))
                 return -EPERM;
 
+        /* prevent nested lock acquisition --- not supported by FMLP */
+        if (tsk_rt(t)->num_locks_held)
+                return -EBUSY;
+
         spin_lock_irqsave(&sem->wait.lock, flags);
 
         if (sem->owner) {
@@ -1613,6 +1617,8 @@ int gsnedf_fmlp_lock(struct litmus_lock* l)
                 spin_unlock_irqrestore(&sem->wait.lock, flags);
         }
 
+        tsk_rt(t)->num_locks_held++;
+
         return 0;
 }
 
@@ -1630,6 +1636,8 @@ int gsnedf_fmlp_unlock(struct litmus_lock* l)
                 goto out;
         }
 
+        tsk_rt(t)->num_locks_held--;
+
         /* check if there are jobs waiting for this resource */
         next = __waitqueue_remove_first(&sem->wait);
         if (next) {
diff --git a/litmus/sched_pfp.c b/litmus/sched_pfp.c
index fdcf8a41684a..56d5a61c25e4 100644
--- a/litmus/sched_pfp.c
+++ b/litmus/sched_pfp.c
@@ -571,6 +571,11 @@ int pfp_fmlp_lock(struct litmus_lock* l)
         if (!is_realtime(t))
                 return -EPERM;
 
+        /* prevent nested lock acquisition --- not supported by FMLP */
+        if (tsk_rt(t)->num_locks_held ||
+            tsk_rt(t)->num_local_locks_held)
+                return -EBUSY;
+
         spin_lock_irqsave(&sem->wait.lock, flags);
 
         /* tie-break by this point in time */
@@ -615,6 +620,8 @@ int pfp_fmlp_lock(struct litmus_lock* l)
                 spin_unlock_irqrestore(&sem->wait.lock, flags);
         }
 
+        tsk_rt(t)->num_locks_held++;
+
         return 0;
 }
 
@@ -632,6 +639,8 @@ int pfp_fmlp_unlock(struct litmus_lock* l)
                 goto out;
         }
 
+        tsk_rt(t)->num_locks_held--;
+
         /* we lose the benefit of priority boosting */
 
         unboost_priority(t);
@@ -807,6 +816,11 @@ int pfp_mpcp_lock(struct litmus_lock* l)
         if (!is_realtime(t))
                 return -EPERM;
 
+        /* prevent nested lock acquisition */
+        if (tsk_rt(t)->num_locks_held ||
+            tsk_rt(t)->num_local_locks_held)
+                return -EBUSY;
+
         preempt_disable();
 
         if (sem->vspin)
@@ -857,6 +871,8 @@ int pfp_mpcp_lock(struct litmus_lock* l)
                 spin_unlock_irqrestore(&sem->wait.lock, flags);
         }
 
+        tsk_rt(t)->num_locks_held++;
+
         return 0;
 }
 
@@ -874,6 +890,9 @@ int pfp_mpcp_unlock(struct litmus_lock* l)
                 goto out;
         }
 
+
+        tsk_rt(t)->num_locks_held--;
+
         /* we lose the benefit of priority boosting */
 
         unboost_priority(t);
@@ -1267,12 +1286,18 @@ int pfp_pcp_lock(struct litmus_lock* l)
         if (!is_realtime(t) || from != to)
                 return -EPERM;
 
+        /* prevent nested lock acquisition in global critical section */
+        if (tsk_rt(t)->num_locks_held)
+                return -EBUSY;
+
         preempt_disable();
 
         pcp_raise_ceiling(sem, eprio);
 
         preempt_enable();
 
+        tsk_rt(t)->num_local_locks_held++;
+
         return 0;
 }
 
@@ -1290,6 +1315,8 @@ int pfp_pcp_unlock(struct litmus_lock* l)
                 goto out;
         }
 
+        tsk_rt(t)->num_local_locks_held--;
+
         /* give it back */
         pcp_lower_ceiling(sem);
 
@@ -1310,7 +1337,9 @@ int pfp_pcp_open(struct litmus_lock* l, void* __user config)
                 /* we need to know the real-time priority */
                 return -EPERM;
 
-        if (get_user(cpu, (int*) config))
+        if (!config)
+                cpu = get_partition(t);
+        else if (get_user(cpu, (int*) config))
                 return -EFAULT;
 
         /* make sure the resource location matches */
@@ -1445,6 +1474,11 @@ int pfp_dpcp_lock(struct litmus_lock* l)
         if (!is_realtime(t))
                 return -EPERM;
 
+        /* prevent nested lock accquisition */
+        if (tsk_rt(t)->num_locks_held ||
+            tsk_rt(t)->num_local_locks_held)
+                return -EBUSY;
+
         preempt_disable();
 
         /* Priority-boost ourself *before* we suspend so that
@@ -1461,6 +1495,8 @@ int pfp_dpcp_lock(struct litmus_lock* l)
 
         preempt_enable();
 
+        tsk_rt(t)->num_locks_held++;
+
         return 0;
 }
 
@@ -1478,6 +1514,8 @@ int pfp_dpcp_unlock(struct litmus_lock* l)
                 goto out;
         }
 
+        tsk_rt(t)->num_locks_held--;
+
         home = sem->owner_cpu;
 
         /* give it back */
@@ -1633,7 +1671,9 @@ static long pfp_allocate_lock(struct litmus_lock **lock, int type,
 
         case PCP_SEM:
                 /* Priority Ceiling Protocol */
-                if (get_user(cpu, (int*) config))
+                if (!config)
+                        cpu = get_partition(current);
+                else if (get_user(cpu, (int*) config))
                         return -EFAULT;
 
                 if (!cpu_online(cpu))
diff --git a/litmus/sched_psn_edf.c b/litmus/sched_psn_edf.c
index 63fa6103882a..fabff1be9bba 100644
--- a/litmus/sched_psn_edf.c
+++ b/litmus/sched_psn_edf.c
@@ -434,6 +434,11 @@ int psnedf_fmlp_lock(struct litmus_lock* l)
         if (!is_realtime(t))
                 return -EPERM;
 
+        /* prevent nested lock acquisition --- not supported by FMLP */
+        if (tsk_rt(t)->num_locks_held ||
+            tsk_rt(t)->num_local_locks_held)
+                return -EBUSY;
+
         spin_lock_irqsave(&sem->wait.lock, flags);
 
         if (sem->owner) {
@@ -474,6 +479,8 @@ int psnedf_fmlp_lock(struct litmus_lock* l)
                 spin_unlock_irqrestore(&sem->wait.lock, flags);
         }
 
+        tsk_rt(t)->num_locks_held++;
+
         return 0;
 }
 
@@ -491,6 +498,8 @@ int psnedf_fmlp_unlock(struct litmus_lock* l)
                 goto out;
         }
 
+        tsk_rt(t)->num_locks_held--;
+
         /* we lose the benefit of priority boosting */
 
         unboost_priority(t);
diff --git a/litmus/sched_task_trace.c b/litmus/sched_task_trace.c
index e863eaf41b96..8d75437e7771 100644
--- a/litmus/sched_task_trace.c
+++ b/litmus/sched_task_trace.c
@@ -16,6 +16,9 @@
 #include <litmus/feather_trace.h>
 #include <litmus/ftdev.h>
 
+#ifdef CONFIG_SCHED_LITMUS_TRACEPOINT
+#define CREATE_TRACE_POINTS
+#endif
 
 #define NUM_EVENTS              (1 << (CONFIG_SCHED_TASK_TRACE_SHIFT+11))
 
diff --git a/litmus/srp.c b/litmus/srp.c
index 5ffdc9e7dc5b..e04088bf2cb4 100644
--- a/litmus/srp.c
+++ b/litmus/srp.c
@@ -98,11 +98,16 @@ static void srp_add_prio(struct srp* srp, struct srp_priority* prio)
 
 static int lock_srp_semaphore(struct litmus_lock* l)
 {
+        struct task_struct* t = current;
         struct srp_semaphore* sem = container_of(l, struct srp_semaphore, litmus_lock);
 
-        if (!is_realtime(current))
+        if (!is_realtime(t))
                 return -EPERM;
 
+        /* prevent acquisition of local locks in global critical sections */
+        if (tsk_rt(t)->num_locks_held)
+                return -EBUSY;
+
         preempt_disable();
 
         /* Update ceiling. */
@@ -111,9 +116,11 @@ static int lock_srp_semaphore(struct litmus_lock* l)
         /* SRP invariant: all resources available */
         BUG_ON(sem->owner != NULL);
 
-        sem->owner = current;
+        sem->owner = t;
         TRACE_CUR("acquired srp 0x%p\n", sem);
 
+        tsk_rt(t)->num_local_locks_held++;
+
         preempt_enable();
 
         return 0;
@@ -121,12 +128,13 @@ static int lock_srp_semaphore(struct litmus_lock* l)
 
 static int unlock_srp_semaphore(struct litmus_lock* l)
 {
+        struct task_struct* t = current;
         struct srp_semaphore* sem = container_of(l, struct srp_semaphore, litmus_lock);
         int err = 0;
 
         preempt_disable();
 
-        if (sem->owner != current) {
+        if (sem->owner != t) {
                 err = -EINVAL;
         } else {
                 /* Determine new system priority ceiling for this CPU. */
@@ -138,6 +146,8 @@ static int unlock_srp_semaphore(struct litmus_lock* l)
                 /* Wake tasks on this CPU, if they exceed current ceiling. */
                 TRACE_CUR("released srp 0x%p\n", sem);
                 wake_up_all(&__get_cpu_var(srp).ceiling_blocked);
+
+                tsk_rt(t)->num_local_locks_held--;
         }
 
         preempt_enable();