From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Borntraeger Subject: [PATCH 3/5] s390: make cpu_relax a barrier again Date: Fri, 21 Oct 2016 13:58:56 +0200 Message-ID: <1477051138-1610-4-git-send-email-borntraeger@de.ibm.com> References: <1477051138-1610-1-git-send-email-borntraeger@de.ibm.com> Return-path: In-Reply-To: <1477051138-1610-1-git-send-email-borntraeger@de.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: Peter Zijlstra Cc: Nicholas Piggin , linux-kernel@vger.kernel.org, linux-s390 , linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Heiko Carstens , Martin Schwidefsky , Noam Camus , Christian Borntraeger List-ID: stop_machine seems to be the only important place for yielding during cpu_relax. This was fixed by using cpu_relax_yield. Therefore, we can now redefine cpu_relax to be a barrier instead. (With the option to do some SMT tuning later on) Signed-off-by: Christian Borntraeger --- arch/s390/include/asm/processor.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index d05965b..5d262cf 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -236,7 +236,7 @@ static inline unsigned short stap(void) */ void cpu_relax_yield(void); -#define cpu_relax() cpu_relax_yield() +#define cpu_relax() barrier() #define cpu_relax_lowlatency() barrier() #define ECAG_CACHE_ATTRIBUTE 0 -- 2.5.5