powerpc/smp: smp_ops->kick_cpu() should be able to fail

When we start a cpu we use smp_ops->kick_cpu(), which currently
returns void, it should be able to fail. Convert it to return
int, and update all uses.

Convert all the current error cases to return -ENOENT, which is
what would eventually be returned by __cpu_up() currently when
it doesn't detect the cpu as coming up in time.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

2 files changed, 6 insertions, 5 deletions

diff --git a/arch/powerpc/platforms/cell/beat_smp.c b/arch/powerpc/platforms/cell/beat_smp.c
index 26efc204c47f..996df33165f1 100644
--- a/arch/powerpc/platforms/cell/beat_smp.c
+++ b/arch/powerpc/platforms/cell/beat_smp.c
@@ -93,12 +93,11 @@ static void __devinit smp_beatic_setup_cpu(int cpu)
         beatic_setup_cpu(cpu);
 }
 
-static void __devinit smp_celleb_kick_cpu(int nr)
+static int __devinit smp_celleb_kick_cpu(int nr)
 {
         BUG_ON(nr < 0 || nr >= NR_CPUS);
 
-        if (!smp_startup_cpu(nr))
-                return;
+        return smp_startup_cpu(nr);
 }
 
 static int smp_celleb_cpu_bootable(unsigned int nr)
diff --git a/arch/powerpc/platforms/cell/smp.c b/arch/powerpc/platforms/cell/smp.c
index f774530075b7..03d638e2f44f 100644
--- a/arch/powerpc/platforms/cell/smp.c
+++ b/arch/powerpc/platforms/cell/smp.c
@@ -137,12 +137,12 @@ static void __devinit smp_cell_setup_cpu(int cpu)
         mtspr(SPRN_DABRX, DABRX_KERNEL | DABRX_USER);
 }
 
-static void __devinit smp_cell_kick_cpu(int nr)
+static int __devinit smp_cell_kick_cpu(int nr)
 {
         BUG_ON(nr < 0 || nr >= NR_CPUS);
 
         if (!smp_startup_cpu(nr))
-                return;
+                return -ENOENT;
 
         /*
          * The processor is currently spinning, waiting for the
@@ -150,6 +150,8 @@ static void __devinit smp_cell_kick_cpu(int nr)
          * the processor will continue on to secondary_start
          */
         paca[nr].cpu_start = 1;
+
+        return 0;
 }
 
 static int smp_cell_cpu_bootable(unsigned int nr)