padata: purge get_cpu and reorder_via_wq from padata_do_serial

BugLink: https://bugs.launchpad.net/bugs/1883916

[ Upstream commit 065cf577]

With the removal of the padata timer, padata_do_serial no longer
needs special CPU handling, so remove it.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

kernel/padata.c

@@ -322,24 +322,9 @@ static void padata_serial_worker(struct work_struct *serial_work)
  */
 void padata_do_serial(struct padata_priv *padata)
 {
-	int cpu;
-	struct padata_parallel_queue *pqueue;
-	struct parallel_data *pd;
-	int reorder_via_wq = 0;
-
-	pd = padata->pd;
-
-	cpu = get_cpu();
-
-	/* We need to enqueue the padata object into the correct
-	 * per-cpu queue.
-	 */
-	if (cpu != padata->cpu) {
-		reorder_via_wq = 1;
-		cpu = padata->cpu;
-	}
-
-	pqueue = per_cpu_ptr(pd->pqueue, cpu);
+	struct parallel_data *pd = padata->pd;
+	struct padata_parallel_queue *pqueue = per_cpu_ptr(pd->pqueue,
+							   padata->cpu);
 
 	spin_lock(&pqueue->reorder.lock);
 	list_add_tail(&padata->list, &pqueue->reorder.list);
@@ -353,8 +338,6 @@ void padata_do_serial(struct padata_priv *padata)
 	 */
 	smp_mb__after_atomic();
 
-	put_cpu();
-
 	padata_reorder(pd);
 }
 EXPORT_SYMBOL(padata_do_serial);