All of lore.kernel.org
 help / color / mirror / Atom feed
From: David Mosberger <davidm@napali.hpl.hp.com>
To: linux-ia64@vger.kernel.org
Subject: Re: [PATCH] do_gettimeofday() fails to compensate for lost ticks
Date: Wed, 24 Sep 2003 18:02:21 +0000	[thread overview]
Message-ID: <marc-linux-ia64-106442674331918@msgid-missing> (raw)
In-Reply-To: <marc-linux-ia64-106442430128845@msgid-missing>

>>>>> On Wed, 24 Sep 2003 11:21:19 -0600 (MDT), Khalid Aziz <khalid@fc.hp.com> said:

  Khalid> do_gettimeofday() needs to account for lost ticks before
  Khalid> returning current time and it fails to do
  Khalid> that. do_gettimeofday() on other architectures compensate
  Khalid> for lost ticks correctly. Due to this bug, if you repeatedly
  Khalid> do clock_settime() immediately followed by clock_gettime()
  Khalid> and compare the time returned by clock_gettime() to the time
  Khalid> set by clock_settime(), you will eventually see clock going
  Khalid> backwards. I am attaching a test program from POSIX
  Khalid> testsuite at the end that exposes this bug. Run this test in
  Khalid> a continuous loop that stops when test fails.

This explanation doesn't sound right.  See the "lost" variable in
gettimeoffset().  It's supposed to account for lost ticks.

	--david


  reply	other threads:[~2003-09-24 18:02 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-09-24 17:21 [PATCH] do_gettimeofday() fails to compensate for lost ticks Khalid Aziz
2003-09-24 18:02 ` David Mosberger [this message]
2003-09-24 18:17 ` Khalid Aziz
2003-09-24 18:21 ` Jesse Barnes
2003-09-24 18:29 ` David Mosberger
2003-09-24 18:31 ` Khalid Aziz
2003-09-24 18:58 ` Khalid Aziz
2003-09-24 19:25 ` David Mosberger

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=marc-linux-ia64-106442674331918@msgid-missing \
    --to=davidm@napali.hpl.hp.com \
    --cc=linux-ia64@vger.kernel.org \
    /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.