diff options
| author | Nick Desaulniers <ndesaulniers@google.com> | 2021-06-21 16:18:22 -0700 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2021-06-22 11:07:18 -0700 |
| commit | 51c2ee6d121ceb31ab8d35aff4ce53007aefb455 (patch) | |
| tree | 9f6d82ee01a13154a7c4eb4c4db87073b5379b8a /init | |
| parent | ae4d682dfd3350d9836dafeed1fc5aa1e27c4963 (diff) | |
| download | lwn-51c2ee6d121ceb31ab8d35aff4ce53007aefb455.tar.gz lwn-51c2ee6d121ceb31ab8d35aff4ce53007aefb455.zip | |
Kconfig: Introduce ARCH_WANTS_NO_INSTR and CC_HAS_NO_PROFILE_FN_ATTR
We don't want compiler instrumentation to touch noinstr functions,
which are annotated with the no_profile_instrument_function function
attribute. Add a Kconfig test for this and make GCOV depend on it, and
in the future, PGO.
If an architecture is using noinstr, it should denote that via this
Kconfig value. That makes Kconfigs that depend on noinstr able to express
dependencies in an architecturally agnostic way.
Cc: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/lkml/YMTn9yjuemKFLbws@hirez.programming.kicks-ass.net/
Link: https://lore.kernel.org/lkml/YMcssV%2Fn5IBGv4f0@hirez.programming.kicks-ass.net/
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210621231822.2848305-4-ndesaulniers@google.com
Diffstat (limited to 'init')
| -rw-r--r-- | init/Kconfig | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/init/Kconfig b/init/Kconfig index 1ea12c64e4c9..31397a7a45fb 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -83,6 +83,9 @@ config TOOLS_SUPPORT_RELR config CC_HAS_ASM_INLINE def_bool $(success,echo 'void foo(void) { asm inline (""); }' | $(CC) -x c - -c -o /dev/null) +config CC_HAS_NO_PROFILE_FN_ATTR + def_bool $(success,echo '__attribute__((no_profile_instrument_function)) int x();' | $(CC) -x c - -c -o /dev/null -Werror) + config CONSTRUCTORS bool |