[pk,fesvr] improved proxykernel build system

Now uses a modified MCPPBS.  Add --host=riscv to configure path.

Front-end server now just searches PATH for riscv-pk, so just install the pk
to somewhere in your path.

1 files changed, 43 insertions, 0 deletions

diff --git a/pk/atomic.h b/pk/atomic.h
new file mode 100644
index 0000000..3294b6c
--- /dev/null
+++ b/pk/atomic.h
@@ -0,0 +1,43 @@
+#ifndef _RISCV_ATOMIC_H
+#define _RISCV_ATOMIC_H
+
+typedef struct { long val; } atomic_t;
+typedef struct { atomic_t lock; } spinlock_t;
+#define SPINLOCK_INIT {{0}}
+
+static inline long atomic_add(atomic_t* a, long inc)
+{
+  long old = a->val;
+  a->val += inc;
+  return old;
+}
+
+static inline long atomic_swap(atomic_t* a, long val)
+{
+  long old = a->val;
+  a->val = val;
+  return old;
+}
+
+static inline void atomic_set(atomic_t* a, long val)
+{
+  a->val = val;
+}
+
+static inline long atomic_read(atomic_t* a)
+{
+  return a->val;
+}
+
+static inline void spinlock_lock(spinlock_t* lock)
+{
+  while(atomic_read(&lock->lock))
+    while(atomic_swap(&lock->lock,-1));
+}
+
+static inline void spinlock_unlock(spinlock_t* lock)
+{
+  atomic_set(&lock->lock,0);
+}
+
+#endif