[PATCH v16 04/21] powerpc: Only use task_struct 'cpu' field on SMP

[Michael Ellerman]

From: Christophe Leroy <christophe.leroy at c-s.fr>

When moving to CONFIG_THREAD_INFO_IN_TASK, the thread_info 'cpu' field
gets moved into task_struct and only defined when CONFIG_SMP is set.

This patch ensures that TI_CPU is only used when CONFIG_SMP is set and
that task_struct 'cpu' field is not used directly out of SMP code.

Signed-off-by: Christophe Leroy <christophe.leroy at c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin at gmail.com>
Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
---
 arch/powerpc/kernel/head_fsl_booke.S | 2 ++
 arch/powerpc/kernel/misc_32.S        | 4 ++++
 arch/powerpc/xmon/xmon.c             | 2 +-
 3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 2386ce2a9c6e..2c21e8642a00 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -243,8 +243,10 @@ _ENTRY(__early_start)
 	li	r0,0
 	stwu	r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1)
 
+#ifdef CONFIG_SMP
 	CURRENT_THREAD_INFO(r22, r1)
 	stw	r24, TI_CPU(r22)
+#endif
 
 	bl	early_init
 
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index 57d2ffb2d45c..02b8cdd73792 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -183,10 +183,14 @@ _GLOBAL(low_choose_750fx_pll)
 	or	r4,r4,r5
 	mtspr	SPRN_HID1,r4
 
+#ifdef CONFIG_SMP
 	/* Store new HID1 image */
 	CURRENT_THREAD_INFO(r6, r1)
 	lwz	r6,TI_CPU(r6)
 	slwi	r6,r6,2
+#else
+	li	r6, 0
+#endif
 	addis	r6,r6,nap_save_hid1 at ha
 	stw	r4,nap_save_hid1 at l(r6)
 
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 757b8499aba2..a0f44f992360 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -2997,7 +2997,7 @@ static void show_task(struct task_struct *tsk)
 	printf("%px %016lx %6d %6d %c %2d %s\n", tsk,
 		tsk->thread.ksp,
 		tsk->pid, rcu_dereference(tsk->parent)->pid,
-		state, task_thread_info(tsk)->cpu,
+		state, task_cpu(tsk),
 		tsk->comm);
 }
 
-- 
2.20.1