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| author | Masahiro Yamada <yamada.masahiro@socionext.com> | 2018-12-31 00:14:15 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-04 08:02:34 +0200 |
| commit | 0276ebf16675f3745d8b6f384dcf917e1379eda2 (patch) | |
| tree | 916496126f4c63fb188de8685b1a4d94bf007744 /arch/x86/include | |
| parent | 753328727cab4116410f2a3c150826ab6c555d6a (diff) | |
| download | linux-stable-0276ebf16675f3745d8b6f384dcf917e1379eda2.tar.gz linux-stable-0276ebf16675f3745d8b6f384dcf917e1379eda2.tar.bz2 linux-stable-0276ebf16675f3745d8b6f384dcf917e1379eda2.zip | |
jump_label: move 'asm goto' support test to Kconfig
commit e9666d10a5677a494260d60d1fa0b73cc7646eb3 upstream.
Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".
The jump label is controlled by HAVE_JUMP_LABEL, which is defined
like this:
#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
# define HAVE_JUMP_LABEL
#endif
We can improve this by testing 'asm goto' support in Kconfig, then
make JUMP_LABEL depend on CC_HAS_ASM_GOTO.
Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
match to the real kernel capability.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
[nc: Fix trivial conflicts in 4.19
arch/xtensa/kernel/jump_label.c doesn't exist yet
Ensured CC_HAVE_ASM_GOTO and HAVE_JUMP_LABEL were sufficiently
eliminated]
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/cpufeature.h | 2 | ||||
| -rw-r--r-- | arch/x86/include/asm/jump_label.h | 13 | ||||
| -rw-r--r-- | arch/x86/include/asm/rmwcc.h | 6 |
3 files changed, 4 insertions, 17 deletions
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index aced6c9290d6..ce95b8cbd229 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -140,7 +140,7 @@ extern void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int bit); #define setup_force_cpu_bug(bit) setup_force_cpu_cap(bit) -#if defined(__clang__) && !defined(CC_HAVE_ASM_GOTO) +#if defined(__clang__) && !defined(CONFIG_CC_HAS_ASM_GOTO) /* * Workaround for the sake of BPF compilation which utilizes kernel diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h index 8c0de4282659..7010e1c594c4 100644 --- a/arch/x86/include/asm/jump_label.h +++ b/arch/x86/include/asm/jump_label.h @@ -2,19 +2,6 @@ #ifndef _ASM_X86_JUMP_LABEL_H #define _ASM_X86_JUMP_LABEL_H -#ifndef HAVE_JUMP_LABEL -/* - * For better or for worse, if jump labels (the gcc extension) are missing, - * then the entire static branch patching infrastructure is compiled out. - * If that happens, the code in here will malfunction. Raise a compiler - * error instead. - * - * In theory, jump labels and the static branch patching infrastructure - * could be decoupled to fix this. - */ -#error asm/jump_label.h included on a non-jump-label kernel -#endif - #define JUMP_LABEL_NOP_SIZE 5 #ifdef CONFIG_X86_64 diff --git a/arch/x86/include/asm/rmwcc.h b/arch/x86/include/asm/rmwcc.h index 4914a3e7c803..033dc7ca49e9 100644 --- a/arch/x86/include/asm/rmwcc.h +++ b/arch/x86/include/asm/rmwcc.h @@ -4,7 +4,7 @@ #define __CLOBBERS_MEM(clb...) "memory", ## clb -#if !defined(__GCC_ASM_FLAG_OUTPUTS__) && defined(CC_HAVE_ASM_GOTO) +#if !defined(__GCC_ASM_FLAG_OUTPUTS__) && defined(CONFIG_CC_HAS_ASM_GOTO) /* Use asm goto */ @@ -21,7 +21,7 @@ cc_label: \ #define __BINARY_RMWcc_ARG " %1, " -#else /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CC_HAVE_ASM_GOTO) */ +#else /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CONFIG_CC_HAS_ASM_GOTO) */ /* Use flags output or a set instruction */ @@ -36,7 +36,7 @@ do { \ #define __BINARY_RMWcc_ARG " %2, " -#endif /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CC_HAVE_ASM_GOTO) */ +#endif /* defined(__GCC_ASM_FLAG_OUTPUTS__) || !defined(CONFIG_CC_HAS_ASM_GOTO) */ #define GEN_UNARY_RMWcc(op, var, arg0, cc) \ __GEN_RMWcc(op " " arg0, var, cc, __CLOBBERS_MEM()) |