"noirq suspend" in the linux kernel

Question

What does noirq suspend mean in the context of the linux kernel ?I've come across this log in the output of dmesg :

PM: noirq suspend of devices failed

Any ideas ?

Answer 1

Thanks to the comment made by @0andriy, I found the description of that in the linux kernel source code(include/linux/pm.h) :

@suspend_noirq: Complete the actions started by @suspend(). Carry out any additional operations required for suspending the device that might be racing with its driver's interrupt handler, which is guaranteed not to run while @suspend_noirq() is being executed. It generally is expected that the device will be in a low-power state (appropriate for the target system sleep state) after subsystem-level @suspend_noirq() has returned successfully. If the device can generate system wakeup signals and is enabled to wake up the system, it should be configured to do so at that time. However, depending on the platform and device's subsystem, @suspend() or @suspend_late() may be allowed to put the device into the low-power state and configure it to generate wakeup signals, in which case it generally is not necessary to define @suspend_noirq().