[SPARC64]: Change TIF_BLKCOMMIT into a fault code.

Eliminates costly atomic bitops in do_sparc64_fault.
Signed-off-by: David S. Miller <davem@redhat.com>

arch/sparc64/lib/copy_page.S

@@ -168,9 +168,9 @@ copy_user_page:		/* %o0=dest, %o1=src, %o2=vaddr */
 
 9:
 	VISEntry
-	ldx		[%g6 + TI_FLAGS], %g3
+	ldub		[%g6 + TI_FAULT_CODE], %g3
 	mov		%o0, %g1
-	andcc		%g3, _TIF_BLKCOMMIT, %g0
+	cmp		%g3, 0
 	rd		%asi, %g3
 	be,a,pt		%icc, 1f
 	 wr		%g0, ASI_BLK_P, %asi

arch/sparc64/mm/fault.c

@@ -428,7 +428,8 @@ asmlinkage void do_sparc64_fault(struct pt_regs *regs)
 		if (tlb_type == spitfire &&
 		    (vma->vm_flags & VM_EXEC) != 0 &&
 		    vma->vm_file != NULL)
-			set_thread_flag(TIF_BLKCOMMIT);
+			set_thread_fault_code(fault_code |
+					      FAULT_CODE_BLKCOMMIT);
 	} else {
 		/* Allow reads even for write-only mappings */
 		if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
@@ -497,6 +498,5 @@ asmlinkage void do_sparc64_fault(struct pt_regs *regs)
 fault_done:
 	/* These values are no longer needed, clear them. */
 	set_thread_fault_code(0);
-	clear_thread_flag(TIF_BLKCOMMIT);
 	current_thread_info()->fault_address = 0;
 }

include/asm-sparc64/thread_info.h

@@ -47,6 +47,7 @@ struct thread_info {
 	struct pt_regs		*kregs;
 	struct exec_domain	*exec_domain;
 	int			preempt_count;
+	int			__pad;
 
 	unsigned long		*utraps;
 
@@ -101,10 +102,11 @@ struct thread_info {
 #define TI_FPREGS	0x00000500
 
 /* We embed this in the uppermost byte of thread_info->flags */
-#define FAULT_CODE_WRITE	0x01	/* Write access, implies D-TLB		*/
-#define FAULT_CODE_DTLB		0x02	/* Miss happened in D-TLB		*/
-#define FAULT_CODE_ITLB		0x04	/* Miss happened in I-TLB		*/
-#define FAULT_CODE_WINFIXUP	0x08	/* Miss happened during spill/fill	*/
+#define FAULT_CODE_WRITE	0x01	/* Write access, implies D-TLB	   */
+#define FAULT_CODE_DTLB		0x02	/* Miss happened in D-TLB	   */
+#define FAULT_CODE_ITLB		0x04	/* Miss happened in I-TLB	   */
+#define FAULT_CODE_WINFIXUP	0x08	/* Miss happened during spill/fill */
+#define FAULT_CODE_BLKCOMMIT	0x10	/* Use blk-commit ASI in copy_page */
 
 #if PAGE_SHIFT == 13
 #define THREAD_SIZE (2*PAGE_SIZE)
@@ -218,10 +220,7 @@ register struct thread_info *current_thread_info_reg asm("g6");
 #define TIF_NEWSIGNALS		6	/* wants new-style signals */
 #define TIF_32BIT		7	/* 32-bit binary */
 #define TIF_NEWCHILD		8	/* just-spawned child process */
-
-/* XXX Make this one FAULT_CODE_BLKCOMMIT XXX */
-#define TIF_BLKCOMMIT		9	/* use ASI_BLK_COMMIT_* in copy_user_page */
-
+/* TIF_* value 9 is available */
 #define TIF_POLLING_NRFLAG	10
 #define TIF_SYSCALL_SUCCESS	11
 /* NOTE: Thread flags >= 12 should be ones we have no interest
@@ -239,7 +238,6 @@ register struct thread_info *current_thread_info_reg asm("g6");
 #define _TIF_NEWSIGNALS		(1<<TIF_NEWSIGNALS)
 #define _TIF_32BIT		(1<<TIF_32BIT)
 #define _TIF_NEWCHILD		(1<<TIF_NEWCHILD)
-#define _TIF_BLKCOMMIT		(1<<TIF_BLKCOMMIT)
 #define _TIF_POLLING_NRFLAG	(1<<TIF_POLLING_NRFLAG)
 #define _TIF_ABI_PENDING	(1<<TIF_ABI_PENDING)
 #define _TIF_SYSCALL_SUCCESS	(1<<TIF_SYSCALL_SUCCESS)