Re: [PATCH RT] nvdimm: make lane acquirement RT aware
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
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CPU 1 CPU 2
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get lock for Lane 1 get lock for Lane 2
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migrate to CPU 2 migrate to CPU 1
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wait lock for Lane 2 wait lock for Lane 1
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_____________________________
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dead lock ?
Bummer. That would dead lock indeed.
Is it easily possible to recognize the recursive case?
Thanks,
Yognxin
Sebastian