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On Fri, Nov 22, 2013 at 3:13 AM, Volker Armin Hemmann |
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<volkerarmin@××××××××××.com> wrote: |
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> Am 21.11.2013 20:52, schrieb Mark Knecht: |
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>> Hi, |
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>> I've been having a problem with new versions of Virtualbox hanging |
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>> my system completely, but only if I use the CONFIG_PREEMPT option. |
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>> I.e. - Preemptable Kernel (Low Latency Desktop) The problem does not |
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>> occur if I select Voluntary Preemption. |
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>> |
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>> The Oracle guys who do Virtualbox development has asked me to try |
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>> full preempt but disable the PREEMPT_RCU option as a test. I think |
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>> possibly Paul McKenney works on the RCU stuff and also frequenct this |
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>> list so possibly he or someone else here can tell me where I find the |
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>> option to completely disable the RCU stuff. (If it exists...) |
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>> |
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>> I'm currently running gentoo-sources-3.10.19, trying to build 3.10.20. |
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>> |
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>> Specifically, here's where I am now: |
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>> |
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>> c2RAID6 linux # cat .config | grep PREEMPT |
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>> CONFIG_TREE_PREEMPT_RCU=y |
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>> CONFIG_PREEMPT_RCU=y |
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>> CONFIG_PREEMPT_NOTIFIERS=y |
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>> # CONFIG_PREEMPT_NONE is not set |
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>> # CONFIG_PREEMPT_VOLUNTARY is not set |
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>> CONFIG_PREEMPT=y |
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>> CONFIG_PREEMPT_COUNT=y |
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>> CONFIG_DEBUG_PREEMPT=y |
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>> c2RAID6 linux # |
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>> |
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>> I found General Setup-> RCU Subsystem but I'm ot clear what option |
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>> might allow me to do what I think the Oracle devs are asking me to do. |
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>> |
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>> If I need a newer/different kernel let me know. |
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>> |
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>> Thanks, |
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>> Mark |
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>> |
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>> |
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> make menuconfig |
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> hit slash |
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> type in RCU |
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> |
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> it will tell you where to find stuff |
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> |
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> |
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|
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And the only thing that I see that looks like a candidate says |
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|
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Symbol: PREEMPT_RCU [=y] |
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│ |
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│ Type : boolean |
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│ |
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│ Defined at init/Kconfig:472 |
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which doesn't give me any option to change it in make menuconfig. |
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If you feel a different option is in there that I'm not seeing I'd |
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certainly appreciate knowing which one it is. |
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Under General Setup -> RCU Subsystem using a ? on each line suggests |
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none of the lines in that section are associated with PREEMPT_RCU. As |
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you seem to know where it is please let me know. |
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|
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Thanks, |
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Mark |
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