All of lore.kernel.org
 help / color / mirror / Atom feed
From: Arnd Bergmann <arnd@arndb.de>
To: Martin Peschke <mp3@de.ibm.com>
Cc: Andrew Morton <akpm@osdl.org>,
	linux-kernel@vger.kernel.org, ak@suse.de, hch@infradead.org,
	arjan@infradead.org, James.Smart@emulex.com,
	James.Bottomley@steeleye.com
Subject: Re: [RFC] [Patch 7/8] statistics infrastructure - exploitation prerequisite
Date: Wed, 17 May 2006 01:03:08 +0200	[thread overview]
Message-ID: <200605170103.08917.arnd@arndb.de> (raw)
In-Reply-To: <446A53DE.6060400@de.ibm.com>

Am Wednesday 17 May 2006 00:36 schrieb Martin Peschke:
> Any other hints on how to replace my sched_clock() calls are welcome.
> (I want to measure elapsed times in units that are understandable to
> users without hardware manuals and calculator, such as milliseconds.)

There are a number of APIs that allow you to get the time:

- do_gettimeofday
  potentially slow, reliable TOD clock, microsecond resolution
- ktime_get_ts
  monotonic clock, nanosecond resolution
- getnstimeofday
  reliable, nanosecond TOD clock
- xtime
  jiffie accurate TOD clock, with fast reads
- xtime + wall_to_monotonic
  jiffie accurate monotonic clock, almost as fast
- get_cycles
  highest supported resolution and accuracy, highly
  HW-specific behaviour, may overflow.

	Arnd <><

  reply	other threads:[~2006-05-16 23:03 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-05-16 17:47 [RFC] [Patch 7/8] statistics infrastructure - exploitation prerequisite Martin Peschke
2006-05-16 18:28 ` Andrew Morton
2006-05-16 22:36   ` Martin Peschke
2006-05-16 23:03     ` Arnd Bergmann [this message]
2006-05-17  1:23       ` Peter Chubb
2006-05-17  1:27         ` Andi Kleen
2006-05-17  1:43           ` Peter Chubb
2006-05-17  2:24             ` Christoph Lameter
2006-05-17  1:13     ` Peter Chubb
2006-05-17  2:32   ` Nick Piggin

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=200605170103.08917.arnd@arndb.de \
    --to=arnd@arndb.de \
    --cc=James.Bottomley@steeleye.com \
    --cc=James.Smart@emulex.com \
    --cc=ak@suse.de \
    --cc=akpm@osdl.org \
    --cc=arjan@infradead.org \
    --cc=hch@infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mp3@de.ibm.com \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.