PCP: allow NULL config parameter

When the config parameter is NULL, just default to the local CPU,
which is what we want in 99% of the cases anyway.

1 files changed, 6 insertions, 2 deletions

diff --git a/litmus/sched_pfp.c b/litmus/sched_pfp.c
index 0e875a3b5cba..e3c3bd770efa 100644
--- a/litmus/sched_pfp.c
+++ b/litmus/sched_pfp.c
@@ -1292,7 +1292,9 @@ 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 */
@@ -1613,7 +1615,9 @@ 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))