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| author | Masahiro Yamada <yamada.masahiro@socionext.com> | 2018-12-31 00:14:15 +0900 |
|---|---|---|
| committer | Masahiro Yamada <yamada.masahiro@socionext.com> | 2019-01-06 09:46:51 +0900 |
| commit | e9666d10a5677a494260d60d1fa0b73cc7646eb3 (patch) | |
| tree | fd609e683efff32ed6cc1458e20c40969328a33e /arch/Kconfig | |
| parent | 72d3ebb929de339f991fc49b58942d2d5ecdb753 (diff) | |
| download | lwn-e9666d10a5677a494260d60d1fa0b73cc7646eb3.tar.gz lwn-e9666d10a5677a494260d60d1fa0b73cc7646eb3.zip | |
jump_label: move 'asm goto' support test to Kconfig
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>
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 b70c952ac838..4cfb6de48f79 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 |