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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: D0AE412002E X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: nrbwubooewxt7cabcj3mb5co3iarag7s X-HE-Tag: 1698335377-413410 X-HE-Meta: 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 yyawBZ3b LW5otMTuea6tumsHmMQ/wuHaHbLCB/kfOmf1y8R2Uvdc38Lis966QZsz3DBV7AszsswzXZ17vDACv8L/1nfoXTIiOD9V2F2hZH5MhraVUPitR0NIhzco9Z5RQoWERmTdtV5bmZKezwVn2pWlT+rLYTTS4UQTpDe/YPtpeBKVk5+61jz6XMsBhllx7Qr4JOz03kNGRO3pHqFxz1851lR3HWEkUK4euLSaa0G1jkeA5Y4h1E5mJ7T3FCarThNh/06SlB7iGwJM0b8Gj/YE= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, 26 Oct 2023 09:40:35 -0400 Steven Rostedt wrote: > Hence, why I don't want to associate this with priority inheritance. The > time constraint is a fundamental difference. Let me add one more fundamental difference here that makes this solution different than priority inheritance and ceiling. PI and ceiling define the correctness of the system. If you get it wrong or remove it, the system can be incorrect and lock up, fail deadlines, etc. There's hundreds, if not thousands of papers mathematically defining the correctness of PI, ceiling and proxy execution, as they are complex and critical for the system to behave properly. This feature is a performance boost only, and has nothing to do with "correctness". That's because it has that arbitrary time where it can run a little more. It's more like the difference between having something in cache and a cache miss. This would cause many academics to quit and find a job in sales if they had to prove the correctness of an algorithm that gave you a boost for some random amount of time. The idea here is to help with performance. If it exists, great, your application will likely perform better. If it doesn't, no big deal, you may just have to deal with longer wait times on critical sections. This is why I do not want to associate this as another form of PI or ceiling. -- Steve