[POWERPC] Add thread_info_cache_init() weak hook

Some architectures need to maintain a kmem cache for thread info
structures.  The next commit adds that to powerpc to fix an alignment
problem.

There is no good arch callback to use to initialize that cache
that I can find, so this adds a new one in the form of a weak
function whose default is empty.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/init/main.c b/init/main.c
index 833a67d..507c9fb 100644
--- a/init/main.c
+++ b/init/main.c
@@ -525,6 +525,10 @@ void __init __attribute__((weak)) smp_setup_processor_id(void)
 {
 }
 
+void __init __weak thread_info_cache_init(void)
+{
+}
+
 asmlinkage void __init start_kernel(void)
 {
 	char * command_line;
@@ -645,6 +649,7 @@ asmlinkage void __init start_kernel(void)
 	if (efi_enabled)
 		efi_enter_virtual_mode();
 #endif
+	thread_info_cache_init();
 	fork_init(num_physpages);
 	proc_caches_init();
 	buffer_init();