x86: replace percpu_xxx funcs with this_cpu_xxx

Since percpu_xxx() serial functions are duplicated with this_cpu_xxx().
Removing percpu_xxx() definition and replacing them by this_cpu_xxx()
in code. There is no function change in this patch, just preparation for
later percpu_xxx serial function removing.

On x86 machine the this_cpu_xxx() serial functions are same as
__this_cpu_xxx() without no unnecessary premmpt enable/disable.

Thanks for Stephen Rothwell, he found and fixed a i386 build error in
the patch.

Also thanks for Andrew Morton, he kept updating the patchset in Linus'
tree.

Signed-off-by: Alex Shi <alex.shi@intel.com>
Acked-by: Christoph Lameter <cl@gentwo.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 5 insertions, 5 deletions

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 43d8b48b23e6..28e810255a0a 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -237,7 +237,7 @@ start_thread_common(struct pt_regs *regs, unsigned long new_ip,
         current->thread.usersp  = new_sp;
         regs->ip                = new_ip;
         regs->sp                = new_sp;
-        percpu_write(old_rsp, new_sp);
+        this_cpu_write(old_rsp, new_sp);
         regs->cs                = _cs;
         regs->ss                = _ss;
         regs->flags             = X86_EFLAGS_IF;
@@ -359,11 +359,11 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
         /*
          * Switch the PDA and FPU contexts.
          */
-        prev->usersp = percpu_read(old_rsp);
-        percpu_write(old_rsp, next->usersp);
-        percpu_write(current_task, next_p);
+        prev->usersp = this_cpu_read(old_rsp);
+        this_cpu_write(old_rsp, next->usersp);
+        this_cpu_write(current_task, next_p);
 
-        percpu_write(kernel_stack,
+        this_cpu_write(kernel_stack,
                   (unsigned long)task_stack_page(next_p) +
                   THREAD_SIZE - KERNEL_STACK_OFFSET);