[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>

2 files changed, 6 insertions, 3 deletions

diff --git a/include/asm-i386/current.h b/include/asm-i386/current.h
index 3cbbecd79016..5252ee0f6d7a 100644
--- a/include/asm-i386/current.h
+++ b/include/asm-i386/current.h
@@ -1,13 +1,14 @@
 #ifndef _I386_CURRENT_H
 #define _I386_CURRENT_H
 
-#include <linux/thread_info.h>
+#include <asm/pda.h>
+#include <linux/compiler.h>
 
 struct task_struct;
 
-static __always_inline struct task_struct * get_current(void)
+static __always_inline struct task_struct *get_current(void)
 {
-        return current_thread_info()->task;
+        return read_pda(pcurrent);
 }
  
 #define current get_current()
diff --git a/include/asm-i386/pda.h b/include/asm-i386/pda.h
index f90fde22566d..08a35c478af2 100644
--- a/include/asm-i386/pda.h
+++ b/include/asm-i386/pda.h
@@ -7,12 +7,14 @@
 #define _I386_PDA_H
 
 #include <linux/stddef.h>
+#include <linux/types.h>
 
 struct i386_pda
 {
         struct i386_pda *_pda;          /* pointer to self */
 
         int cpu_number;
+        struct task_struct *pcurrent;   /* current process */
 };
 
 extern struct i386_pda *_cpu_pda[];