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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-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 574311C0009 X-Stat-Signature: ez4zh94myrucqt3om84ctwn46dopf4q7 X-HE-Tag: 1739216674-441639 X-HE-Meta: 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 Z+b9wUuL CZKv6R6DOvJ7mivB9apZHkeHxV0Iy/UFCcPLqi2y60PgTRteIh1lkTZr87b5Q9V0CotnwpGB0tJVkAzneuotrDKv3I7ER9gUctQtxrJupJQHZ8+ukNdH6rP1+w1CV7brHuUHoOEdIt80rSVH/isxCMYkGI9/mkPhhyG/WD9m3o3kOcuL5vPvous0bw3Wzln79LAEL0tgXQ9PGynsqpD/swO9L2c8Wqa6dYe+E4dneFc3Pyb2V1k6AuzSujPY+Sl4ohLBgyFw9i5BO4cO/L+zqlp5hVjf0MDosEtrnLl3Sr05lbdiU+lj4o2ZOlFMYWz2ILAsAiPUCS1qWnW2SmXfWCSkcKMNXw8K4BsL37WuzfLIl9/hKKD+t9If2ekCfzxsVSquLy0+2hj2Zn4VO5I5iI8O+5w== 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 Mon, 10 Feb 2025 12:27:00 -0500 Steven Rostedt wrote: > On Mon, 10 Feb 2025 17:20:59 +0000 > David Laight wrote: > > > Hmmm... you lose big-time anyway. > > > > All you need is a lot of network traffic 'pinch' the process context until > > the hardware interrupt, NAPI softint code and rcu softint code completes. > > That can easily take several milliseconds. > > Not on PREEMPT_RT. All that runs as threads. > > And this is a feature that we would like on RT for non RT tasks. Actually, this doesn't even need PREEMPT_RT to not hit your example. You can build and boot your system with interrupts as threads, and that also includes softirqs. -- Steve