[POWERPC] ppc64: support CONFIG_DEBUG_PREEMPT

Add CONFIG_DEBUG_PREEMPT support to ppc64: it was useful for testing
get_paca() preemption.  Cheat a little, just use debug_smp_processor_id()
in the debug version of get_paca(): it contains all the right checks and
reporting, though get_paca() doesn't really use smp_processor_id().

Use local_paca for what might have been called __raw_get_paca().
Silence harmless warnings from io.h and lparcfg.c with local_paca -
it is okay for iseries_lparcfg_data to be referencing shared_proc
with preemption enabled: all cpus should show the same value for
shared_proc.

Why do other architectures need TRACE_IRQFLAGS_SUPPORT for DEBUG_PREEMPT?
I don't know, ppc64 appears to get along fine without it.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/asm-powerpc/io.h b/include/asm-powerpc/io.h
index 6805efb2cb6d..affba7052fb6 100644
--- a/include/asm-powerpc/io.h
+++ b/include/asm-powerpc/io.h
@@ -86,7 +86,7 @@ extern unsigned long pci_dram_offset;
  */
 
 #ifdef CONFIG_PPC64
-#define IO_SET_SYNC_FLAG()      do { get_paca()->io_sync = 1; } while(0)
+#define IO_SET_SYNC_FLAG()      do { local_paca->io_sync = 1; } while(0)
 #else
 #define IO_SET_SYNC_FLAG()
 #endif