From: Andrew Morton <akpm@osdl.org>
Date: Wed, 9 Nov 2005 23:45:30 +0000 (-0800)
Subject: [PATCH] powerpc: sched fixups
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e4d76e1c0b15590f2ad9bba89426c2520cd22ca6;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

[PATCH] powerpc: sched fixups

- Re-add a hunk lost during merge: ppc64 is missing the hunk that disables
  preempt on the secondary CPUs before they call cpu_idle().

- ppc's cpu_idle() had the need_resched() test wrong.

Cc: Nick Piggin <nickpiggin@yahoo.com.au>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 5c330c3366e4..36d67a8d7cbb 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -510,6 +510,7 @@ int __devinit start_secondary(void *unused)
 
 	smp_store_cpu_info(cpu);
 	set_dec(tb_ticks_per_jiffy);
+	preempt_disable();
 	cpu_callin_map[cpu] = 1;
 
 	smp_ops->setup_cpu(cpu);
diff --git a/arch/ppc/kernel/idle.c b/arch/ppc/kernel/idle.c
index 3c4e4cb61074..821a75e45602 100644
--- a/arch/ppc/kernel/idle.c
+++ b/arch/ppc/kernel/idle.c
@@ -63,7 +63,7 @@ void cpu_idle(void)
 	int cpu = smp_processor_id();
 
 	for (;;) {
-		while (need_resched()) {
+		while (!need_resched()) {
 			if (ppc_md.idle != NULL)
 				ppc_md.idle();
 			else