On Sun, Dec 06 2020 at 17:38, Thomas Gleixner wrote:
On Fri, Dec 04 2020 at 18:43, Jerry Snitselaar wrote:
Now that kstat_irqs is exported, get rid of count_interrupts in i915_pmu.c
May I ask why this has been merged in the first place?
Nothing in a driver has ever to fiddle with the internals of an irq descriptor. We have functions for properly accessing them. Just because C allows to fiddle with everything is not a justification. If the required function is not exported then adding the export with a proper explanation is not asked too much.
Also this lacks protection or at least a comment why this can be called safely and is not subject to a concurrent removal of the irq descriptor. The same problem exists when calling kstat_irqs(). It's even documented at the top of the function.
And as pointed out vs. that TPM thing this really could have been a trivial
i915->irqs++;
in the interrupt handler and a read of that instead of iterating over all possible cpus and summing it up. Oh well...
Thanks,
tglx