linux-kernel - RE: [PATCH v11 01/13] x86/resctrl: Replace smp_call_function_many() with on_each_cpu

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Message-ID: <SJ1PR11MB6083AA5292C11145BEEBAF6FFCFC9@SJ1PR11MB6083.namprd11.prod.outlook.com>
Date:   Wed, 11 Jan 2023 19:05:48 +0000
From:   "Luck, Tony" <tony.luck@...el.com>
To:     "Raj, Ashok" <ashok.raj@...el.com>
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Subject: RE: [PATCH v11 01/13] x86/resctrl: Replace smp_call_function_many()
 with on_each_cpu_mask()

> I wasn't sure if the few ms difference is going to make much material
> difference for that process. IPI's does shake things up and introduces
> other overheads not related to this process.

Is it just a few milli-seconds? What is the scheduler priority of the kernel
thread you wake to perform this action? How does that compare to the
priority of a RT thread?  I may be wrong here, but I think an RT thread can
block a kernel thread from running indefinitely.

-Tony