powerpc/8xx: Move DataStoreTLBMiss perf handler

Move DataStoreTLBMiss perf handler in order to cope
with future growing exception prolog.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/75dd28b04efd2cbdbf01153173d99c11cdff2f08.1576916812.git.christophe.leroy@c-s.fr

arch/powerpc/kernel/head_8xx.S

@@ -166,18 +166,6 @@ SystemCall:
  */
 	EXCEPTION(0x1000, SoftEmu, program_check_exception, EXC_XFER_STD)
 
-/* Called from DataStoreTLBMiss when perf TLB misses events are activated */
-#ifdef CONFIG_PERF_EVENTS
-	patch_site	0f, patch__dtlbmiss_perf
-0:	lwz	r10, (dtlb_miss_counter - PAGE_OFFSET)@l(0)
-	addi	r10, r10, 1
-	stw	r10, (dtlb_miss_counter - PAGE_OFFSET)@l(0)
-	mfspr	r10, SPRN_DAR
-	mtspr	SPRN_DAR, r11	/* Tag DAR */
-	mfspr	r11, SPRN_M_TW
-	rfi
-#endif
-
 	. = 0x1100
 /*
  * For the MPC8xx, this is a software tablewalk to load the instruction
@@ -486,6 +474,18 @@ DARFixed:/* Return from dcbx instruction bug workaround */
 	/* 0x300 is DataAccess exception, needed by bad_page_fault() */
 	EXC_XFER_LITE(0x300, handle_page_fault)
 
+/* Called from DataStoreTLBMiss when perf TLB misses events are activated */
+#ifdef CONFIG_PERF_EVENTS
+	patch_site	0f, patch__dtlbmiss_perf
+0:	lwz	r10, (dtlb_miss_counter - PAGE_OFFSET)@l(0)
+	addi	r10, r10, 1
+	stw	r10, (dtlb_miss_counter - PAGE_OFFSET)@l(0)
+	mfspr	r10, SPRN_DAR
+	mtspr	SPRN_DAR, r11	/* Tag DAR */
+	mfspr	r11, SPRN_M_TW
+	rfi
+#endif
+
 /* On the MPC8xx, these next four traps are used for development
  * support of breakpoints and such.  Someday I will get around to
  * using them.