4 files changed, 20 insertions, 8 deletions

diff --git a/arch/riscv64/conf/init b/arch/riscv64/conf/init
index 47e733f..11d838c 100755
--- a/arch/riscv64/conf/init
+++ b/arch/riscv64/conf/init
diff --git a/arch/riscv64/conf/init.c b/arch/riscv64/conf/init.c
index 1886760..45274d9 100644
--- a/arch/riscv64/conf/init.c
+++ b/arch/riscv64/conf/init.c
@@ -133,10 +133,15 @@ void _start()
 	if (pid != 0) {
 		print_value("Child pid: ", pid);
 		puts("Swapping to child...\n");
-		sys_swap(pid);
-		puts("We shouldn't be here?\n");
-		while(1);
+		while(1) sys_swap(pid);
 	}
 
 	puts("Hello from child!\n");
+
+	puts("Doing 1M swaps...\n");
+	start = sys_ticks();
+	for (long i = 0; i < 1000000; ++i)
+		sys_swap(1);
+	uint64_t ticks = sys_ticks() - start;
+	print_value("1M swaps took ", ticks / second);
 }
diff --git a/arch/riscv64/conf/initrd b/arch/riscv64/conf/initrd
index 24f9fb4..5c0c9bb 100644
--- a/arch/riscv64/conf/initrd
+++ b/arch/riscv64/conf/initrd
diff --git a/arch/riscv64/kernel/proc.c b/arch/riscv64/kernel/proc.c
index d2b8dfb..2ccc5bc 100644
--- a/arch/riscv64/kernel/proc.c
+++ b/arch/riscv64/kernel/proc.c
@@ -30,7 +30,7 @@ void run_init(struct tcb *t, void *fdt)
 
 void set_args(struct tcb *t, struct sys_ret a)
 {
-	struct riscv_regs *r = (struct riscv_regs *)(--t);
+	struct riscv_regs *r = (struct riscv_regs *)(t) - 1;
 	r->a0 = a.s;
 	r->a1 = a.ar0;
 	r->a2 = a.ar1;
@@ -41,7 +41,7 @@ void set_args(struct tcb *t, struct sys_ret a)
 
 struct sys_ret get_args(struct tcb *t)
 {
-	struct riscv_regs *r = (struct riscv_regs *)(--t);
+	struct riscv_regs *r = (struct riscv_regs *)(t) - 1;
 	return SYS_RET6(r->a0, r->a1, r->a2, r->a3, r->a4, r->a5);
 }
 
@@ -49,7 +49,7 @@ void set_thread(struct tcb *t)
 {
 	/* get location of registers in memory */
 	/** \todo check alignment, should be fine but just to be sure */
-	struct riscv_regs *r = (struct riscv_regs *)(--t);
+	struct riscv_regs *r = (struct riscv_regs *)(t) - 1;
 
 	/* insert important values into register slots */
 	r->sp = (long)t->thread_stack_top;
@@ -58,16 +58,23 @@ void set_thread(struct tcb *t)
 
 void save_regs(struct tcb *t, void *p)
 {
-	struct riscv_regs *r = (struct riscv_regs *)(t++);
+	struct riscv_regs *r = (struct riscv_regs *)(t) - 1;
 	memcpy(p, r, sizeof(*r));
 }
 
 void load_regs(void *p, struct tcb *t)
 {
-	struct riscv_regs *r = (struct riscv_regs *)(t++);
+	struct riscv_regs *r = (struct riscv_regs *)(t) - 1;
 	memcpy(r, p, sizeof(*r));
 }
 
+void clone_regs(struct tcb *d, struct tcb *s)
+{
+	struct riscv_regs *rd = (struct riscv_regs *)(d) - 1;
+	struct riscv_regs *rs = (struct riscv_regs *)(s) - 1;
+	memcpy(rd, rs, sizeof(*rs));
+}
+
 void adjust_ipi(struct tcb *t)
 {
 	UNUSED(t);