linux-kernel - [PATCH v2 1/6] Revert "arm64: alternatives: add enable parameter to conditional asm macros"

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Message-Id: <20160628170732.523-2-andre.przywara@arm.com>
Date:	Tue, 28 Jun 2016 18:07:27 +0100
From:	Andre Przywara <andre.przywara@....com>
To:	Catalin Marinas <catalin.marinas@....com>,
	Will Deacon <will.deacon@....com>
Cc:	Suzuki K Poulose <Suzuki.Poulose@....com>,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [PATCH v2 1/6] Revert "arm64: alternatives: add enable parameter to conditional asm macros"

Commit 77ee306c0aea9 ("arm64: alternatives: add enable parameter to
conditional asm macros") extended the alternative assembly macros.
Unfortunately this does not really work as one would expect, as the
enable parameter in fact correctly protects the alternative section
magic, but not the actual code sequences.
This results in having both the original instruction(s) _and_  the
alternative ones, if enable if false.
Since there is no user of this macros anyway, just revert it.

This reverts commit 77ee306c0aea9a219daec256ad25982944affef8.

Signed-off-by: Andre Przywara <andre.przywara@....com>
---
 arch/arm64/include/asm/alternative.h | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/include/asm/alternative.h b/arch/arm64/include/asm/alternative.h
index beccbde..7288071 100644
--- a/arch/arm64/include/asm/alternative.h
+++ b/arch/arm64/include/asm/alternative.h
@@ -95,13 +95,11 @@ void apply_alternatives(void *start, size_t length);
  * The code that follows this macro will be assembled and linked as
  * normal. There are no restrictions on this code.
  */
-.macro alternative_if_not cap, enable = 1
-	.if \enable
+.macro alternative_if_not cap
 	.pushsection .altinstructions, "a"
 	altinstruction_entry 661f, 663f, \cap, 662f-661f, 664f-663f
 	.popsection
 661:
-	.endif
 .endm
 
 /*
@@ -118,22 +116,18 @@ void apply_alternatives(void *start, size_t length);
  *    alternative sequence it is defined in (branches into an
  *    alternative sequence are not fixed up).
  */
-.macro alternative_else, enable = 1
-	.if \enable
+.macro alternative_else
 662:	.pushsection .altinstr_replacement, "ax"
 663:
-	.endif
 .endm
 
 /*
  * Complete an alternative code sequence.
  */
-.macro alternative_endif, enable = 1
-	.if \enable
+.macro alternative_endif
 664:	.popsection
 	.org	. - (664b-663b) + (662b-661b)
 	.org	. - (662b-661b) + (664b-663b)
-	.endif
 .endm
 
 #define _ALTERNATIVE_CFG(insn1, insn2, cap, cfg, ...)	\
-- 
2.9.0