One gc thread moves a delay list to a tofree list

Each core's gc thread free elements on the tofree list

One gc thread moves a delay list to a tofree list
1a129849 · Frans Kaashoek · cdaa456b · 1a129849 · 1a129849 · 1a129849
--- a/gc.c
+++ b/gc.c
--- a/kernel.h
+++ b/kernel.h
@@ -23,7 +23,6 @@ struct stat;
 struct proc;
 struct vmap;
 struct pipe;
-struct gc;

 // bio.c
 void            binit(void);

--- a/proc.h
+++ b/proc.h
@@ -54,10 +54,8 @@ struct proc {
  SLIST_ENTRY(proc) child_next;
  struct condvar cv;
  u64 epoch;
-  u64 ndelayed;
-  struct gc *gc_epoch;
-  struct spinlock gc_lock;
-  u64 rcu_read_depth;
+  struct spinlock gc_epoch_lock;
+  u64 epoch_depth;
  char lockname[16];
  int on_runq;
  int cpu_pin;