mm/kfence: remove hung_task cruft

commit fdf756f7 ("sched: Fix more TASK_state comparisons") makes
hung_task not to monitor TASK_IDLE tasks.  The special handling to
workaround hung_task warnings is not required anymore.

Link: https://lkml.kernel.org/r/1667986006-25420-1-git-send-email-quic_pkondeti@quicinc.comSigned-off-by: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/kfence/core.c

@@ -26,7 +26,6 @@
 #include <linux/random.h>
 #include <linux/rcupdate.h>
 #include <linux/sched/clock.h>
-#include <linux/sched/sysctl.h>
 #include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
@@ -799,16 +798,7 @@ static void toggle_allocation_gate(struct work_struct *work)
 	/* Enable static key, and await allocation to happen. */
 	static_branch_enable(&kfence_allocation_key);
 
-	if (sysctl_hung_task_timeout_secs) {
-		/*
-		 * During low activity with no allocations we might wait a
-		 * while; let's avoid the hung task warning.
-		 */
-		wait_event_idle_timeout(allocation_wait, atomic_read(&kfence_allocation_gate),
-					sysctl_hung_task_timeout_secs * HZ / 2);
-	} else {
-		wait_event_idle(allocation_wait, atomic_read(&kfence_allocation_gate));
-	}
+	wait_event_idle(allocation_wait, atomic_read(&kfence_allocation_gate));
 
 	/* Disable static key and reset timer. */
 	static_branch_disable(&kfence_allocation_key);