tile: don't assume user privilege is zero

Technically, user privilege is anything less than kernel
privilege.  We modify the existing user_mode() macro to have
this semantic (and use it in a couple of places it wasn't being
used before), and add an IS_KERNEL_EX1() macro to the assembly
code as well.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

arch/tile/include/asm/processor.h

@@ -15,6 +15,8 @@
 #ifndef _ASM_TILE_PROCESSOR_H
 #define _ASM_TILE_PROCESSOR_H
 
+#include <arch/chip.h>
+
 #ifndef __ASSEMBLY__
 
 /*
@@ -25,7 +27,6 @@
 #include <asm/ptrace.h>
 #include <asm/percpu.h>
 
-#include <arch/chip.h>
 #include <arch/spr_def.h>
 
 struct task_struct;
@@ -347,7 +348,6 @@ extern int kdata_huge;
 
 /*
  * Provide symbolic constants for PLs.
- * Note that assembly code assumes that USER_PL is zero.
  */
 #define USER_PL 0
 #if CONFIG_KERNEL_PL == 2

arch/tile/include/asm/ptrace.h

@@ -39,7 +39,7 @@ typedef unsigned long pt_reg_t;
 #define user_stack_pointer(regs) ((regs)->sp)
 
 /* Does the process account for user or for system time? */
-#define user_mode(regs) (EX1_PL((regs)->ex1) == USER_PL)
+#define user_mode(regs) (EX1_PL((regs)->ex1) < KERNEL_PL)
 
 /* Fill in a struct pt_regs with the current kernel registers. */
 struct pt_regs *get_pt_regs(struct pt_regs *);