x86/mce: don't use [delayed_]work_pending()

There's no need to test whether a (delayed) work item in pending
before queueing, flushing or cancelling it.  Most uses are unnecessary
and quite a few of them are buggy.

Remove unnecessary pending tests from x86/mce.  Only compile tested.

v2: Local var work removed from mce_schedule_work() as suggested by
    Borislav.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac@vger.kernel.org

arch/x86/kernel/cpu/mcheck/mce.c

@@ -512,11 +512,8 @@ int mce_available(struct cpuinfo_x86 *c)
 
 static void mce_schedule_work(void)
 {
-	if (!mce_ring_empty()) {
-		struct work_struct *work = &__get_cpu_var(mce_work);
-		if (!work_pending(work))
-			schedule_work(work);
-	}
+	if (!mce_ring_empty())
+		schedule_work(&__get_cpu_var(mce_work));
 }
 
 DEFINE_PER_CPU(struct irq_work, mce_irq_work);
@@ -1351,12 +1348,7 @@ int mce_notify_irq(void)
 		/* wake processes polling /dev/mcelog */
 		wake_up_interruptible(&mce_chrdev_wait);
 
-		/*
-		 * There is no risk of missing notifications because
-		 * work_pending is always cleared before the function is
-		 * executed.
-		 */
-		if (mce_helper[0] && !work_pending(&mce_trigger_work))
+		if (mce_helper[0])
 			schedule_work(&mce_trigger_work);
 
 		if (__ratelimit(&ratelimit))