irq: Add irq_tasks, move NVMe to it

include/zinnia/irq.h

@@ -5,9 +5,7 @@
 #include <zinnia/compiler.h>
 #include <zinnia/errno.h>
 #include <zinnia/list.h>
-#include <zinnia/spin.h>
 #include <zinnia/types.h>
-#include <zinnia/workqueue.h>
 #include <stddef.h>
 #include <stdint.h>
 
@@ -33,6 +31,7 @@ enum irq_mode : uint8_t {
 };
 
 struct irq_line;
+struct irq_task;
 
 struct irq_handler {
     enum irq_status (*raise)(struct irq_handler* self);
@@ -40,9 +39,7 @@ struct irq_handler {
     list_link(struct irq_handler*) next;
 
     struct irq_line* line;
-    struct workqueue* wq;
-    struct work work;
-    bool holds_mask;
+    _Atomic(bool) need;
 };
 
 struct irq_line {
@@ -55,8 +52,7 @@ struct irq_line {
     list_head(struct irq_handler*) handlers;
     enum irq_mode mode;
     enum irq_trigger_mode trigger;
-    struct spinlock thread_lock;
-    size_t threads_pending;
+    struct irq_task* task;
 };
 
 struct msi_line {
@@ -76,7 +72,7 @@ void irq_line_program(struct irq_line* line, enum irq_trigger_mode trigger, enum
 void irq_line_raise(struct irq_line* line);
 void irq_line_attach(struct irq_line* line, struct irq_handler* handler);
 void irq_line_detach(struct irq_line* line, struct irq_handler* handler);
-errno_t irq_line_attach_threaded(struct irq_line* line, struct irq_handler* handler, const char* name);
+errno_t irq_line_attach_task(struct irq_line* line, struct irq_handler* handler, const char* name);
 
 void irq_lock();
 void irq_unlock();

include/zinnia/sched.h

@@ -102,6 +102,7 @@ struct scheduler {
 
     struct timer preempt_timer;
     bool need_resched;
+    bool owe_preempt;
     uint64_t slice_start;
     uint64_t boost_epoch;
 };