From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1ZtHpf-0003kt-1w for user-mode-linux-devel@lists.sourceforge.net; Mon, 02 Nov 2015 16:19:43 +0000 Received: from ivanoab4.miniserver.com ([78.31.104.92]) by sog-mx-1.v43.ch3.sourceforge.com with esmtps (TLSv1:AES128-SHA:128) (Exim 4.76) id 1ZtHpd-0007Ap-Aw for user-mode-linux-devel@lists.sourceforge.net; Mon, 02 Nov 2015 16:19:43 +0000 Message-ID: <56378D16.6090509@kot-begemot.co.uk> Date: Mon, 02 Nov 2015 16:19:34 +0000 From: Anton Ivanov MIME-Version: 1.0 References: <1445416947-824802-1-git-send-email-aivanov@brocade.com> <562D236E.7020108@kot-begemot.co.uk> <562DFC90.9030308@nod.at> <5631BB4E.4010301@kot-begemot.co.uk> <1446304232.3238.8.camel@m3y3r.de> <5634DAA4.70308@nod.at> <1446304594.3238.11.camel@m3y3r.de> <5634DC7B.3010707@nod.at> <56371B6D.3080506@kot-begemot.co.uk> <563720BA.20107@nod.at> <563721BB.10003@kot-begemot.co.uk> <56372439.2070509@nod.at> <5637257A.8000200@kot-begemot.co.uk> <563728E2.5090901@nod.at> <563732B7.7050008@kot-begemot.co.uk> <5637346F.6060004@nod.at> <56377384.2040901@kot-begemot.co.uk> <56378061.2000706@nod.at> In-Reply-To: <56378061.2000706@nod.at> List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net Subject: Re: [uml-devel] [PATCH v3] um: Switch clocksource to hrtimers To: Richard Weinberger , Thomas Meyer Cc: "user-mode-linux-devel@lists.sourceforge.net" On 02/11/15 15:25, Richard Weinberger wrote: > Am 02.11.2015 um 15:30 schrieb Anton Ivanov: >> On 02/11/15 10:01, Richard Weinberger wrote: >>> Am 02.11.2015 um 10:53 schrieb Anton Ivanov: >>>> [snip] >>>> >>>>>>> I'm pretty sure that you don't see the issue as your Jessy userspace uses nanosleep periodically. >>>>>> There are quite a few things running so this may indeed be the case. >>>>>> >>>>>> What do you use for userspace (so I can try to reproduce this and debug it)? >>>>> Debian Squeeze amd64 with almost nothing running. >>>>> >>>>> PID TTY STAT TIME COMMAND >>>>> 2 ? S 0:00 [kthreadd] >>>>> 3 ? S 0:00 \_ [ksoftirqd/0] >>>>> 4 ? S 0:00 \_ [kworker/0:0] >>>>> 5 ? S< 0:00 \_ [kworker/0:0H] >>>>> 6 ? S 0:00 \_ [kworker/u2:0] >>>>> 7 ? S 0:00 \_ [kdevtmpfs] >>>>> 8 ? S< 0:00 \_ [netns] >>>>> 9 ? S< 0:00 \_ [writeback] >>>>> 10 ? S 0:00 \_ [kworker/u2:1] >>>>> 11 ? S< 0:00 \_ [crypto] >>>>> 12 ? S 0:00 \_ [kworker/0:1] >>>>> 13 ? S< 0:00 \_ [bioset] >>>>> 14 ? S< 0:00 \_ [kblockd] >>>>> 15 ? S 0:00 \_ [kswapd0] >>>>> 68 ? S 0:00 \_ [fsnotify_mark] >>>>> 221 ? S< 0:00 \_ [bioset] >>>>> 229 ? S< 0:00 \_ [deferwq] >>>>> 231 ? S 0:00 \_ [jbd2/ubda-8] >>>>> 232 ? S< 0:00 \_ [ext4-rsv-conver] >>>>> 233 ? S< 0:00 \_ [kworker/0:1H] >>>>> 1 ? Ss 0:00 init [2] >>>>> 271 ? S>>>> 297 ? S< 0:00 \_ udevd --daemon >>>>> 298 ? S< 0:00 \_ udevd --daemon >>>>> 549 ? Sl 0:00 /usr/sbin/rsyslogd -c4 >>>>> 580 ? Ss 0:00 /usr/sbin/cron >>>>> 595 ? Ss 0:00 /usr/bin/dbus-daemon --system >>>>> 609 ? Ss 0:00 /usr/sbin/sshd >>>>> 628 tty0 Ss 0:00 /bin/login -- >>>>> 631 tty0 S 0:00 \_ -bash >>>>> 636 tty0 R+ 0:00 \_ ps fax >>>>> 629 tty1 Ss+ 0:00 /sbin/getty 38400 tty1 linux >>>>> 630 ttyS0 Ss+ 0:00 /sbin/getty 115200 ttyS0 linux >>>> I cannot reproduce that by dropping jessie into single user mode so I am going to build a squeeze image and re-test with that. >>> I can also reproduce using init=/bin/bash. >> Reproduced, I think I located the culprit. >> >> We still need to relay the "interruption" signal which broke a nanosleep. >> >> I am testing a fix, which so far is working. If the fix proves viable, I will test it as above (init=/bin/bash) and the normal tests I usually do anyway. >> >> If it works OK, I will submit v4. > Yay! Apologies for that. A few years back I found that I can mask most of the races which this patch is trying to address by pinning to a single CPU. As a result most of my test scripts have a taskset -c 0 in them. The revised version where we restore the relay of nanosleep interruptions checks out for me, I just re-submitted it. I will rebase my ubd patches on top of that and once they work, submit them as well. A. > > Thanks, > //richard the QA engineer ;) > ------------------------------------------------------------------------------ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel