linux-kernel - [PATCH v2] powerpc/8xx: hide itlbie and dtlbie symbols

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Message-Id: <998f5532a4ec358acdbeb4238182f416304b3293.1544687473.git.christophe.leroy@c-s.fr>
Date:   Thu, 13 Dec 2018 08:08:11 +0000 (UTC)
From:   Christophe Leroy <christophe.leroy@....fr>
To:     Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Michael Ellerman <mpe@...erman.id.au>
Cc:     linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH v2] powerpc/8xx: hide itlbie and dtlbie symbols

When disassembling InstructionTLBError we get the following messy code:

c000138c:       7d 84 63 78     mr      r4,r12
c0001390:       75 25 58 00     andis.  r5,r9,22528
c0001394:       75 2a 40 00     andis.  r10,r9,16384
c0001398:       41 a2 00 08     beq     c00013a0 <itlbie>
c000139c:       7c 00 22 64     tlbie   r4,r0

c00013a0 <itlbie>:
c00013a0:       39 40 04 01     li      r10,1025
c00013a4:       91 4b 00 b0     stw     r10,176(r11)
c00013a8:       39 40 10 32     li      r10,4146
c00013ac:       48 00 cc 59     bl      c000e004 <transfer_to_handler>

For a cleaner code dump, this patch replaces itlbie and dtlbie
symbols by local symbols.

c000138c:       7d 84 63 78     mr      r4,r12
c0001390:       75 25 58 00     andis.  r5,r9,22528
c0001394:       75 2a 40 00     andis.  r10,r9,16384
c0001398:       41 a2 00 08     beq     c00013a0 <InstructionTLBError+0xa0>
c000139c:       7c 00 22 64     tlbie   r4,r0
c00013a0:       39 40 04 01     li      r10,1025
c00013a4:       91 4b 00 b0     stw     r10,176(r11)
c00013a8:       39 40 10 32     li      r10,4146
c00013ac:       48 00 cc 59     bl      c000e004 <transfer_to_handler>
Signed-off-by: Christophe Leroy <christophe.leroy@....fr>
---
 v2: Using local named symbol instead of num symbol

 arch/powerpc/kernel/head_8xx.S | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index b171b7c0a0e7..34cd6c260da6 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -548,11 +548,11 @@ InstructionTLBError:
 	mr	r4,r12
 	andis.	r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */
 	andis.	r10,r9,SRR1_ISI_NOPT@h
-	beq+	1f
+	beq+	.Litlbie
 	tlbie	r4
-itlbie:
 	/* 0x400 is InstructionAccess exception, needed by bad_page_fault() */
-1:	EXC_XFER_LITE(0x400, handle_page_fault)
+.Litlbie:
+	EXC_XFER_LITE(0x400, handle_page_fault)
 
 /* This is the data TLB error on the MPC8xx.  This could be due to
  * many reasons, including a dirty update to a pte.  We bail out to
@@ -574,10 +574,10 @@ DARFixed:/* Return from dcbx instruction bug workaround */
 	stw	r5,_DSISR(r11)
 	mfspr	r4,SPRN_DAR
 	andis.	r10,r5,DSISR_NOHPTE@h
-	beq+	1f
+	beq+	.Ldtlbie
 	tlbie	r4
-dtlbie:
-1:	li	r10,RPN_PATTERN
+.Ldtlbie:
+	li	r10,RPN_PATTERN
 	mtspr	SPRN_DAR,r10	/* Tag DAR, to be used in DTLB Error */
 	/* 0x300 is DataAccess exception, needed by bad_page_fault() */
 	EXC_XFER_LITE(0x300, handle_page_fault)
@@ -600,8 +600,8 @@ DataBreakpoint:
 	mtspr	SPRN_SPRG_SCRATCH1, r11
 	mfcr	r10
 	mfspr	r11, SPRN_SRR0
-	cmplwi	cr0, r11, (dtlbie - PAGE_OFFSET)@l
-	cmplwi	cr7, r11, (itlbie - PAGE_OFFSET)@l
+	cmplwi	cr0, r11, (.Ldtlbie - PAGE_OFFSET)@l
+	cmplwi	cr7, r11, (.Litlbie - PAGE_OFFSET)@l
 	beq-	cr0, 11f
 	beq-	cr7, 11f
 	EXCEPTION_PROLOG_1
-- 
2.13.3