linux-kernel - [PATCH 08/14] powerpc: entry: Remove unneeded need

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Date:   Mon, 11 Mar 2019 22:47:46 +0000
From:   Valentin Schneider <valentin.schneider@....com>
To:     linux-kernel@...r.kernel.org
Cc:     Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Michael Ellerman <mpe@...erman.id.au>,
        linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH 08/14] powerpc: entry: Remove unneeded need_resched() loop

Since the enabling and disabling of IRQs within preempt_schedule_irq()
is contained in a need_resched() loop, we don't need the outer arch
code loop.

Signed-off-by: Valentin Schneider <valentin.schneider@....com>
Cc: Benjamin Herrenschmidt <benh@...nel.crashing.org>
Cc: Paul Mackerras <paulus@...ba.org>
Cc: Michael Ellerman <mpe@...erman.id.au>
Cc: linuxppc-dev@...ts.ozlabs.org
---
 arch/powerpc/kernel/entry_32.S | 6 +-----
 arch/powerpc/kernel/entry_64.S | 8 +-------
 2 files changed, 2 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 0768dfd8a64e..ff3fe3824a4a 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -896,11 +896,7 @@ resume_kernel:
 	 */
 	bl	trace_hardirqs_off
 #endif
-1:	bl	preempt_schedule_irq
-	CURRENT_THREAD_INFO(r9, r1)
-	lwz	r3,TI_FLAGS(r9)
-	andi.	r0,r3,_TIF_NEED_RESCHED
-	bne-	1b
+	bl	preempt_schedule_irq
 #ifdef CONFIG_TRACE_IRQFLAGS
 	/* And now, to properly rebalance the above, we tell lockdep they
 	 * are being turned back on, which will happen when we return
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 435927f549c4..9c86c6826856 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -857,13 +857,7 @@ resume_kernel:
 	 * sure we are soft-disabled first and reconcile irq state.
 	 */
 	RECONCILE_IRQ_STATE(r3,r4)
-1:	bl	preempt_schedule_irq
-
-	/* Re-test flags and eventually loop */
-	CURRENT_THREAD_INFO(r9, r1)
-	ld	r4,TI_FLAGS(r9)
-	andi.	r0,r4,_TIF_NEED_RESCHED
-	bne	1b
+	bl	preempt_schedule_irq
 
 	/*
 	 * arch_local_irq_restore() from preempt_schedule_irq above may
-- 
2.20.1