diff options
| 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/Kconfig | |
| parent | 753328727cab4116410f2a3c150826ab6c555d6a (diff) | |
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/Kconfig')
| -rw-r--r-- | arch/Kconfig | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index 6801123932a5..a336548487e6 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -71,6 +71,7 @@ config KPROBES config JUMP_LABEL bool "Optimize very unlikely/likely branches" depends on HAVE_ARCH_JUMP_LABEL + depends on CC_HAS_ASM_GOTO help This option enables a transparent branch optimization that makes certain almost-always-true or almost-always-false branch |