Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753215AbbGNWiy (ORCPT ); Tue, 14 Jul 2015 18:38:54 -0400 Received: from mail-wi0-f175.google.com ([209.85.212.175]:33307 "EHLO mail-wi0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752897AbbGNWiD (ORCPT ); Tue, 14 Jul 2015 18:38:03 -0400 From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Ivan Kokshaysky , Peter Zijlstra , Chris Metcalf , Thomas Gleixner , Preeti U Murthy , Christoph Lameter , Richard Henderson , Ingo Molnar , Viresh Kumar , Rik van Riel Subject: [PATCH 1/4] jiffies: Remove HZ > USEC_PER_SEC special case Date: Wed, 15 Jul 2015 00:37:50 +0200 Message-Id: <1436913473-32720-2-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1436913473-32720-1-git-send-email-fweisbec@gmail.com> References: <1436913473-32720-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2553 Lines: 74 HZ never goes much further 1000 and a bit. And if we ever reach one tick per microsecond, we might be having a problem. Lets stop maintaining this special case, just leave a paranoid check. Reviewed-by: Rik van Riel Cc: Christoph Lameter Cc: Ingo Molnar Cc; John Stultz Cc: Peter Zijlstra Cc: Preeti U Murthy Cc: Rik van Riel Cc: Thomas Gleixner Cc: Viresh Kumar Signed-off-by: Frederic Weisbecker --- include/linux/jiffies.h | 9 +-------- kernel/time/time.c | 10 +++++++--- 2 files changed, 8 insertions(+), 11 deletions(-) diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h index 535fd3b..7c6febe 100644 --- a/include/linux/jiffies.h +++ b/include/linux/jiffies.h @@ -363,18 +363,11 @@ static inline unsigned long msecs_to_jiffies(const unsigned int m) } extern unsigned long __usecs_to_jiffies(const unsigned int u); -#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ) +#if !(USEC_PER_SEC % HZ) static inline unsigned long _usecs_to_jiffies(const unsigned int u) { return (u + (USEC_PER_SEC / HZ) - 1) / (USEC_PER_SEC / HZ); } -#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC) -static inline unsigned long _usecs_to_jiffies(const unsigned int u) -{ - return u * (HZ / USEC_PER_SEC); -} -static inline unsigned long _usecs_to_jiffies(const unsigned int u) -{ #else static inline unsigned long _usecs_to_jiffies(const unsigned int u) { diff --git a/kernel/time/time.c b/kernel/time/time.c index 85d5bb1..ad1bf23 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -268,10 +268,14 @@ EXPORT_SYMBOL(jiffies_to_msecs); unsigned int jiffies_to_usecs(const unsigned long j) { -#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ) + /* + * Hz usually doesn't go much further MSEC_PER_SEC. + * jiffies_to_usecs() and usecs_to_jiffies() depend on that. + */ + BUILD_BUG_ON(HZ > USEC_PER_SEC); + +#if !(USEC_PER_SEC % HZ) return (USEC_PER_SEC / HZ) * j; -#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC) - return (j + (HZ / USEC_PER_SEC) - 1)/(HZ / USEC_PER_SEC); #else # if BITS_PER_LONG == 32 return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32; -- 2.1.4 -- 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/