spin_lock_irqsave vs spin_lock_irq

Posted by cojocar on Stack Overflow See other posts from Stack Overflow or by cojocar
Published on 2010-04-01T10:11:30Z Indexed on 2010/04/01 10:13 UTC
Read the original article Hit count: 211

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kernel

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linux

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spinlock

On a SMP machine we must use spin_lock_irqsave and not spin_lock_irq from interrupt context.

Why would we want to save the flags (which contains the IF)?

Is there another interrupt routine that could interrupt us?

The flags are per CPU?

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