From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: "Liu, Yongxin" <Yongxin.Liu@windriver.com>
Cc: "linux-rt-users@vger.kernel.org" <linux-rt-users@vger.kernel.org>,
"linux-nvdimm@lists.01.org" <linux-nvdimm@lists.01.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"rostedt@goodmis.org" <rostedt@goodmis.org>,
"Gortmaker, Paul <Paul.Gortmaker@windriver.com>,
tglx@linutronix.de" <tglx@linutronix.de>
Subject: Re: [PATCH RT] nvdimm: make lane acquirement RT aware
Date: Mon, 18 Mar 2019 12:40:17 +0100 [thread overview]
Message-ID: <20190318114017.tazjaegln2obt3zg@linutronix.de> (raw)
In-Reply-To: <597B109EC20B76429F71A8A97770610D12A63C81@ALA-MBD.corp.ad.wrs.com>
On 2019-03-18 01:41:10 [+0000], Liu, Yongxin wrote:
>
> Consider the recursive call to nd_region_acquire_lane() in the following situation.
> Will there be a dead lock?
>
>
> Thread A Thread B
> | |
> | |
> CPU 1 CPU 2
> | |
> | |
> get lock for Lane 1 get lock for Lane 2
> | |
> | |
> migrate to CPU 2 migrate to CPU 1
> | |
> | |
> wait lock for Lane 2 wait lock for Lane 1
> | |
> | |
> _____________________________
> |
> dead lock ?
Bummer. That would dead lock indeed.
Is it easily possible to recognize the recursive case?
>
> Thanks,
> Yognxin
Sebastian
_______________________________________________
Linux-nvdimm mailing list
Linux-nvdimm@lists.01.org
https://lists.01.org/mailman/listinfo/linux-nvdimm
WARNING: multiple messages have this Message-ID (diff)
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: "Liu, Yongxin" <Yongxin.Liu@windriver.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-rt-users@vger.kernel.org" <linux-rt-users@vger.kernel.org>,
"tglx@linutronix.de" <tglx@linutronix.de>,
"rostedt@goodmis.org" <rostedt@goodmis.org>,
"dan.j.williams@intel.com" <dan.j.williams@intel.com>,
"pagupta@redhat.com" <pagupta@redhat.com>,
"Gortmaker, Paul" <Paul.Gortmaker@windriver.com>,
"linux-nvdimm@lists.01.org" <linux-nvdimm@lists.01.org>
Subject: Re: [PATCH RT] nvdimm: make lane acquirement RT aware
Date: Mon, 18 Mar 2019 12:40:17 +0100 [thread overview]
Message-ID: <20190318114017.tazjaegln2obt3zg@linutronix.de> (raw)
In-Reply-To: <597B109EC20B76429F71A8A97770610D12A63C81@ALA-MBD.corp.ad.wrs.com>
On 2019-03-18 01:41:10 [+0000], Liu, Yongxin wrote:
>
> Consider the recursive call to nd_region_acquire_lane() in the following situation.
> Will there be a dead lock?
>
>
> Thread A Thread B
> | |
> | |
> CPU 1 CPU 2
> | |
> | |
> get lock for Lane 1 get lock for Lane 2
> | |
> | |
> migrate to CPU 2 migrate to CPU 1
> | |
> | |
> wait lock for Lane 2 wait lock for Lane 1
> | |
> | |
> _____________________________
> |
> dead lock ?
Bummer. That would dead lock indeed.
Is it easily possible to recognize the recursive case?
>
> Thanks,
> Yognxin
Sebastian
next prev parent reply other threads:[~2019-03-18 11:40 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-06 9:57 [PATCH RT] nvdimm: make lane acquirement RT aware Yongxin Liu
2019-03-06 9:57 ` Yongxin Liu
2019-03-06 16:35 ` Dan Williams
2019-03-06 16:35 ` Dan Williams
2019-03-07 14:33 ` Sebastian Andrzej Siewior
2019-03-07 14:33 ` Sebastian Andrzej Siewior
2019-03-08 0:07 ` Liu, Yongxin
2019-03-08 0:07 ` Liu, Yongxin
2019-03-08 9:41 ` Sebastian Andrzej Siewior
2019-03-08 9:41 ` Sebastian Andrzej Siewior
2019-03-11 0:44 ` Liu, Yongxin
2019-03-11 0:44 ` Liu, Yongxin
2019-03-15 16:42 ` Sebastian Andrzej Siewior
2019-03-15 16:42 ` Sebastian Andrzej Siewior
2019-03-18 1:41 ` Liu, Yongxin
2019-03-18 1:41 ` Liu, Yongxin
2019-03-18 11:40 ` Sebastian Andrzej Siewior [this message]
2019-03-18 11:40 ` Sebastian Andrzej Siewior
2019-03-18 11:48 ` Liu, Yongxin
2019-03-18 11:48 ` Liu, Yongxin
2019-03-28 17:38 ` Sebastian Andrzej Siewior
2019-03-28 17:38 ` Sebastian Andrzej Siewior
2019-03-08 6:31 ` Pankaj Gupta
2019-03-08 6:31 ` Pankaj Gupta
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