On Mon, Mar 21, 2016 at 12:41 PM, Vishwas Srivastava <vishu.kernel@gmail.com> wrote:
Kernel code heavily uses the spinlock primitives spin_lock_irqsave/restore plus local interrupt disabling/ enabling, all across the code. Is there a possibility that the interrupts might get missed in this small window
disable interrupts ............. ............. <<<<<<<<<<<---------------------- interrupts is trigerred here
enable interrupts
As per my understanding, During disable period interrupt delivery to a local core is disabled. So, when interrupts are enabled (for that core) again then interrupt will be delivered to that core .So no interrupt missed. But if there are multiple interrupt from same source during the disabled period then core will be interrupted once after interrupts enabled again, i.e. all interrupt except one are missed by core, Thanks, Chetan Nanda
specially when the irq affinity has been set to the same core on which the above mentioned code (disabling / enabling the irq's) runs? How the linux deals with this kind of scenario?
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