[PATCH] i386: Implement "current" with the PDA

Use the pcurrent field in the PDA to implement the "current" macro.  This ends
up compiling down to a single instruction to get the current task.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/i386/kernel/cpu/common.c b/arch/i386/kernel/cpu/common.c
index e476202b887f..6958ae5e2fa5 100644
--- a/arch/i386/kernel/cpu/common.c
+++ b/arch/i386/kernel/cpu/common.c
@@ -651,6 +651,7 @@ __cpuinit int alloc_gdt(int cpu)
 struct i386_pda boot_pda = {
         ._pda = &boot_pda,
         .cpu_number = 0,
+        .pcurrent = &init_task,
 };
 
 static inline void set_kernel_gs(void)
@@ -696,6 +697,7 @@ __cpuinit int init_gdt(int cpu, struct task_struct *idle)
         memset(pda, 0, sizeof(*pda));
         pda->_pda = pda;
         pda->cpu_number = cpu;
+        pda->pcurrent = idle;
 
         return 1;
 }