Redesign reschedule points, allow one operation to reschedule many cpus at once

kernel/proc/reschedule.h

@@ -0,0 +1,20 @@
+#ifndef _KERNEL_PROC_RESCHEDULE_H
+#define _KERNEL_PROC_RESCHEDULE_H
+
+#include <libk/list.h>
+#include <sync/spin_lock.h>
+#include <sys/smp.h>
+
+struct reschedule_entry {
+  struct cpu* cpu;
+  struct list_node_link link;
+};
+
+struct reschedule_ctx {
+  struct list_node_link* entries;
+  spin_lock_t lock;
+};
+
+void reschedule_list_append (struct reschedule_ctx* rctx, struct cpu* cpu);
+
+#endif // _KERNEL_PROC_RESCHEDULE_H