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Message-ID: References: <20250203135935.440018-1-bigeasy@linutronix.de> <20250203135935.440018-4-bigeasy@linutronix.de> <20250203142743.GI7145@noisy.programming.kicks-ass.net> <20250203155114.YVGnCHUT@linutronix.de> <20250204103447.GU7145@noisy.programming.kicks-ass.net> <20250205083926.etxnZAoP@linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250205083926.etxnZAoP@linutronix.de> Hi, On 05/02/25 09:39, Sebastian Andrzej Siewior wrote: > On 2025-02-04 11:34:47 [+0100], Peter Zijlstra wrote: ... > > Anyway, none of this solves anything when a process has both an active > > RT part and an active !RT part (which isn't uncommon AFAICT). > > > > Then the RT bits will still get interference from the !RT bits. Do we > > want to complicate things and consider that? > > I don't think so. The active and inactive are common but it is still the > same process so you can expect it. The ugly part is when it is an > entirely different task and it is random which one it is. Not entirely sure we are thinking about the same situation, but it looks like we have cases of RT tasks that are affected by the underlying issue this set is about because they make use of libraries. So, in this case we have a cross-process (RT/!RT) situation that I am not sure we can address sanely. What do you think? Thanks, Juri