Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Chen Zhongjin <chenzhongjin@huawei.com>
To:     <linux-kernel@vger.kernel.org>, <linux-arch@vger.kernel.org>,
        <linuxppc-dev@lists.ozlabs.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kbuild@vger.kernel.org>, <live-patching@vger.kernel.org>
CC:     <jpoimboe@kernel.org>, <peterz@infradead.org>,
        <catalin.marinas@arm.com>, <will@kernel.org>,
        <masahiroy@kernel.org>, <michal.lkml@markovi.net>,
        <ndesaulniers@google.com>, <mark.rutland@arm.com>,
        <pasha.tatashin@soleen.com>, <broonie@kernel.org>,
        <chenzhongjin@huawei.com>, <rmk+kernel@armlinux.org.uk>,
        <madvenka@linux.microsoft.com>, <christophe.leroy@csgroup.eu>,
        <daniel.thompson@linaro.org>
Subject: [PATCH v6 14/33] objtool: arm64: Add annotate_reachable() for objtools
Date:   Thu, 23 Jun 2022 09:48:58 +0800
Message-ID: <20220623014917.199563-15-chenzhongjin@huawei.com>
In-Reply-To: <20220623014917.199563-1-chenzhongjin@huawei.com>
References: <20220623014917.199563-1-chenzhongjin@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

x86 removed annotate_reachable and replaced it with ASM_REACHABLE
which is not suitable for arm64 micro because there are some cases
GCC will merge duplicate inline asm.

Re-add annotation_reachable() for arm64.

Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
---
 include/linux/compiler.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 01ce94b58b42..c8bce9421fa7 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -117,6 +117,14 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
  */
 #define __stringify_label(n) #n
 
+#define __annotate_reachable(c) ({					\
+	asm volatile(__stringify_label(c) ":\n\t"			\
+			".pushsection .discard.reachable\n\t"		\
+			".long " __stringify_label(c) "b - .\n\t"		\
+			".popsection\n\t");				\
+})
+#define annotate_reachable() __annotate_reachable(__COUNTER__)
+
 #define __annotate_unreachable(c) ({					\
 	asm volatile(__stringify_label(c) ":\n\t"			\
 		     ".pushsection .discard.unreachable\n\t"		\
@@ -129,6 +137,7 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
 #define __annotate_jump_table __section(".rodata..c_jump_table")
 
 #else /* !CONFIG_OBJTOOL */
+#define annotate_reachable()
 #define annotate_unreachable()
 #define __annotate_jump_table
 #endif /* CONFIG_OBJTOOL */
-- 
2.17.1