linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: John Stultz <john.stultz@linaro.org>
To: Linux Kernel <linux-kernel@vger.kernel.org>
Cc: John Stultz <john.stultz@linaro.org>,
	Ingo Molnar <mingo@kernel.org>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Richard Cochran <richardcochran@gmail.com>,
	Prarit Bhargava <prarit@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>
Subject: [PATCH 3/8] time: Explicitly use u32 instead of int for shift values
Date: Fri, 13 Jul 2012 01:21:52 -0400	[thread overview]
Message-ID: <1342156917-25092-4-git-send-email-john.stultz@linaro.org> (raw)
In-Reply-To: <1342156917-25092-1-git-send-email-john.stultz@linaro.org>

Ingo noted that using a u32 instead of int for shift values
would be better to make sure the compiler doesn't unnecessarily
use complex signed arithmetic.

CC: Ingo Molnar <mingo@kernel.org>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Richard Cochran <richardcochran@gmail.com>
CC: Prarit Bhargava <prarit@redhat.com>
CC: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 kernel/time/timekeeping.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index c2f12aa..4fd83df 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -28,7 +28,7 @@ struct timekeeper {
 	/* NTP adjusted clock multiplier */
 	u32			mult;
 	/* The shift value of the current clocksource. */
-	int			shift;
+	u32			shift;
 	/* Number of clock cycles in one NTP interval. */
 	cycle_t			cycle_interval;
 	/* Number of clock shifted nano seconds in one NTP interval. */
@@ -45,7 +45,7 @@ struct timekeeper {
 	s64			ntp_error;
 	/* Shift conversion between clock shifted nano seconds and
 	 * ntp shifted nano seconds. */
-	int			ntp_error_shift;
+	u32			ntp_error_shift;
 
 	/* The current time */
 	struct timespec 	xtime;
@@ -960,7 +960,7 @@ static void timekeeping_adjust(s64 offset)
  *
  * Returns the unconsumed cycles.
  */
-static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
+static cycle_t logarithmic_accumulation(cycle_t offset, u32 shift)
 {
 	u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift;
 	u64 raw_nsecs;
-- 
1.7.9.5


  parent reply	other threads:[~2012-07-13  5:22 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-07-13  5:21 [PATCH 0/8] Time fixes and cleanups for 3.6 John Stultz
2012-07-13  5:21 ` [PATCH 1/8] ntp: Fix STA_INS/DEL clearing bug John Stultz
2012-07-13  5:58   ` Ingo Molnar
2012-07-13 18:36     ` John Stultz
2012-07-15  7:57   ` [tip:timers/urgent] " tip-bot for John Stultz
2012-07-13  5:21 ` [PATCH 2/8] time: Whitespace cleanups per Ingo's requests John Stultz
2012-07-15  8:56   ` [tip:timers/core] time: Whitespace cleanups per Ingo%27s requests tip-bot for John Stultz
2012-07-13  5:21 ` John Stultz [this message]
2012-07-15  8:57   ` [tip:timers/core] time: Explicitly use u32 instead of int for shift values tip-bot for John Stultz
2012-07-13  5:21 ` [PATCH 4/8] time: Condense timekeeper.xtime into xtime_sec John Stultz
2012-07-13  6:00   ` Ingo Molnar
2012-07-15  8:57   ` [tip:timers/core] " tip-bot for John Stultz
2012-08-19 21:02   ` [PATCH 4/8] " Andreas Schwab
2012-08-20 18:58     ` John Stultz
2012-08-20 19:45       ` Andreas Schwab
2012-08-20 19:57         ` John Stultz
2012-08-20 20:04           ` Andreas Schwab
2012-08-21  3:38             ` John Stultz
2012-08-21  7:14               ` Andreas Schwab
2012-08-21 18:14                 ` John Stultz
2012-07-13  5:21 ` [PATCH 5/8] time: Refactor accumulation of nsecs to secs John Stultz
2012-07-13  5:56   ` Ingo Molnar
2012-07-13  6:01   ` Ingo Molnar
2012-07-15  8:58   ` [tip:timers/core] " tip-bot for John Stultz
2012-07-13  5:21 ` [PATCH 6/8] time: Move arch_gettimeoffset() usage into timekeeping_get_ns() John Stultz
2012-07-13  6:03   ` Ingo Molnar
2012-07-15  8:59   ` [tip:timers/core] " tip-bot for John Stultz
2012-07-13  5:21 ` [PATCH 7/8] time: Move xtime_nsec adjustment underflow handling timekeeping_adjust John Stultz
2012-07-13  6:04   ` Ingo Molnar
2012-07-15  9:00   ` [tip:timers/core] " tip-bot for John Stultz
2012-07-13  5:21 ` [PATCH 8/8] time: Rework timekeeping functions to take timekeeper ptr as argument John Stultz
2012-07-15  9:01   ` [tip:timers/core] " tip-bot for John Stultz
2012-07-13  6:05 ` [PATCH 0/8] Time fixes and cleanups for 3.6 Ingo Molnar
2012-07-13 20:49   ` John Stultz

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1342156917-25092-4-git-send-email-john.stultz@linaro.org \
    --to=john.stultz@linaro.org \
    --cc=a.p.zijlstra@chello.nl \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=prarit@redhat.com \
    --cc=richardcochran@gmail.com \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).