Merge tag 'tasklets-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull tasklets API update from Kees Cook:
 "These are the infrastructure updates needed to support converting the
  tasklet API to something more modern (and hopefully for removal
  further down the road).

  There is a 300-patch series waiting in the wings to get set out to
  subsystem maintainers, but these changes need to be present in the
  kernel first. Since this has some treewide changes, I carried this
  series for -next instead of paining Thomas with it in -tip, but it's
  got his Ack.

  This is similar to the timer_struct modernization from a while back,
  but not nearly as messy (I hope). :)

   - Prepare for tasklet API modernization (Romain Perier, Allen Pais,
     Kees Cook)"

* tag 'tasklets-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  tasklet: Introduce new initialization API
  treewide: Replace DECLARE_TASKLET() with DECLARE_TASKLET_OLD()
  usb: gadget: udc: Avoid tasklet passing a global

kernel/backtracetest.c

@@ -29,7 +29,7 @@ static void backtrace_test_irq_callback(unsigned long data)
 	complete(&backtrace_work);
 }
 
-static DECLARE_TASKLET(backtrace_tasklet, &backtrace_test_irq_callback, 0);
+static DECLARE_TASKLET_OLD(backtrace_tasklet, &backtrace_test_irq_callback);
 
 static void backtrace_test_irq(void)
 {

kernel/debug/debug_core.c

@@ -1068,7 +1068,7 @@ static void kgdb_tasklet_bpt(unsigned long ing)
 	atomic_set(&kgdb_break_tasklet_var, 0);
 }
 
-static DECLARE_TASKLET(kgdb_tasklet_breakpoint, kgdb_tasklet_bpt, 0);
+static DECLARE_TASKLET_OLD(kgdb_tasklet_breakpoint, kgdb_tasklet_bpt);
 
 void kgdb_schedule_breakpoint(void)
 {

kernel/irq/resend.c

@@ -45,7 +45,7 @@ static void resend_irqs(unsigned long arg)
 }
 
 /* Tasklet to handle resend: */
-static DECLARE_TASKLET(resend_tasklet, resend_irqs, 0);
+static DECLARE_TASKLET_OLD(resend_tasklet, resend_irqs);
 
 static int irq_sw_resend(struct irq_desc *desc)
 {

kernel/softirq.c

@@ -553,7 +553,10 @@ static void tasklet_action_common(struct softirq_action *a,
 				if (!test_and_clear_bit(TASKLET_STATE_SCHED,
 							&t->state))
 					BUG();
-				t->func(t->data);
+				if (t->use_callback)
+					t->callback(t);
+				else
+					t->func(t->data);
 				tasklet_unlock(t);
 				continue;
 			}
@@ -579,6 +582,18 @@ static __latent_entropy void tasklet_hi_action(struct softirq_action *a)
 	tasklet_action_common(a, this_cpu_ptr(&tasklet_hi_vec), HI_SOFTIRQ);
 }
 
+void tasklet_setup(struct tasklet_struct *t,
+		   void (*callback)(struct tasklet_struct *))
+{
+	t->next = NULL;
+	t->state = 0;
+	atomic_set(&t->count, 0);
+	t->callback = callback;
+	t->use_callback = true;
+	t->data = 0;
+}
+EXPORT_SYMBOL(tasklet_setup);
+
 void tasklet_init(struct tasklet_struct *t,
 		  void (*func)(unsigned long), unsigned long data)
 {
@@ -586,6 +601,7 @@ void tasklet_init(struct tasklet_struct *t,
 	t->state = 0;
 	atomic_set(&t->count, 0);
 	t->func = func;
+	t->use_callback = false;
 	t->data = data;
 }
 EXPORT_SYMBOL(tasklet_init);