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t4240 linux irq affinity to use for multiple cores

Question asked by Emre Kara on Jul 8, 2015
Latest reply on Jul 8, 2015 by Scott Wood

Hi all,

 

We are using custom board based on t4240rdb (SDK V1.6) and want to distribute pci express interrupt to all cpu cores to make load balancing.

Pci express works in legacy mode. irq number is 40.

 

"/proc/irq/40/smp_affinity" value is "ffffff".

 

But, unfortunately, pci interrupt always processed in one core* with this configuration setting. When we change smp_affinity value for some specific cpu core it works fine, but it is not possible to work with multiple cores.

What could be the reason? How should be distributed pcie interrupt for all cpu cores?

 

*pci irq core number starts with CPU0, after resetting smp_affinity to ffffff again, it arbitrarily changing to other cores.

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