Message ID | 1411083621-12064-4-git-send-email-anton@samba.org (mailing list archive) |
---|---|
State | Accepted |
Delegated to: | Michael Ellerman |
Headers | show |
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 90fe77a..7992f35 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -148,6 +148,7 @@ config PPC select HAVE_ARCH_AUDITSYSCALL select ARCH_SUPPORTS_ATOMIC_RMW select HAVE_PERF_EVENTS_NMI if PPC64 + select DCACHE_WORD_ACCESS if PPC64 && CPU_LITTLE_ENDIAN config GENERIC_CSUM def_bool CPU_LITTLE_ENDIAN
Enable on DCACHE_WORD_ACCESS on ppc64le. It should work on ppc64 and ppc32 but we need to do some testing first. A somewhat reasonable testcase used to show the performance improvement - a repeated stat of a 33 byte filename that doesn't exist: #include <sys/types.h> #include <sys/stat.h> #include <unistd.h> #define ITERATIONS 10000000 #define PATH "123456781234567812345678123456781" int main(void) { unsigned long i; struct stat buf; for (i = 0; i < ITERATIONS; i++) stat(PATH, &buf); return 0; } runs 27% faster on POWER8. Signed-off-by: Anton Blanchard <anton@samba.org> --- arch/powerpc/Kconfig | 1 + 1 file changed, 1 insertion(+)