Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757415AbbFQAhP (ORCPT ); Tue, 16 Jun 2015 20:37:15 -0400 Received: from mail.kernel.org ([198.145.29.136]:54193 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757083AbbFQAgz (ORCPT ); Tue, 16 Jun 2015 20:36:55 -0400 From: Andy Lutomirski To: x86@kernel.org Cc: Borislav Petkov , Peter Zijlstra , John Stultz , linux-kernel@vger.kernel.org, Len Brown , Huang Rui , Denys Vlasenko , kvm@vger.kernel.org, Ralf Baechle , Andy Lutomirski Subject: [PATCH v3 06/18] x86/tsc: Use the full 64-bit tsc in tsc_delay Date: Tue, 16 Jun 2015 17:35:54 -0700 Message-Id: X-Mailer: git-send-email 2.4.2 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1366 Lines: 50 As a very minor optimization, tsc_delay was only using the low 32 bits of the TSC. It's a delay function, so just use the whole thing. Signed-off-by: Andy Lutomirski --- arch/x86/lib/delay.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/lib/delay.c b/arch/x86/lib/delay.c index 9a52ad0c0758..35115f3786a9 100644 --- a/arch/x86/lib/delay.c +++ b/arch/x86/lib/delay.c @@ -49,16 +49,16 @@ static void delay_loop(unsigned long loops) /* TSC based delay: */ static void delay_tsc(unsigned long __loops) { - u32 bclock, now, loops = __loops; + u64 bclock, now, loops = __loops; int cpu; preempt_disable(); cpu = smp_processor_id(); rdtsc_barrier(); - rdtscl(bclock); + bclock = native_read_tsc(); for (;;) { rdtsc_barrier(); - rdtscl(now); + now = native_read_tsc(); if ((now - bclock) >= loops) break; @@ -80,7 +80,7 @@ static void delay_tsc(unsigned long __loops) loops -= (now - bclock); cpu = smp_processor_id(); rdtsc_barrier(); - rdtscl(bclock); + bclock = native_read_tsc(); } } preempt_enable(); -- 2.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/