x86: make pda a percpu variable

[ Based on original patch from Christoph Lameter and Mike Travis. ]

As pda is now allocated in percpu area, it can easily be made a proper
percpu variable.  Make it so by defining per cpu symbol from linker
script and declaring it in C code for SMP and simply defining it for
UP.  This change cleans up code and brings SMP and UP closer a bit.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 0 insertions, 10 deletions

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index e99b661a97f4..71b6f6ec96a2 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -26,18 +26,8 @@
 #include <asm/bios_ebda.h>
 #include <asm/trampoline.h>
 
-#ifndef CONFIG_SMP
-/* boot cpu pda, referenced by head_64.S to initialize %gs on UP */
-struct x8664_pda _boot_cpu_pda;
-#endif
-
 void __init x86_64_init_pda(void)
 {
-#ifdef CONFIG_SMP
-        cpu_pda(0) = (void *)__per_cpu_load;
-#else
-        cpu_pda(0) = &_boot_cpu_pda;
-#endif
         pda_init(0);
 }