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[213.44.141.166]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-432da27f4f8sm209297365e9.18.2024.11.19.14.51.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 Nov 2024 14:51:54 -0800 (PST) From: Valentin Schneider To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org, x86@kernel.org, rcu@vger.kernel.org, linux-kselftest@vger.kernel.org, Masami Hiramatsu , Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Paolo Bonzini , Wanpeng Li , Vitaly Kuznetsov , Andy Lutomirski , Peter Zijlstra , Frederic Weisbecker , "Paul E. McKenney" , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , Lorenzo Stoakes , Josh Poimboeuf , Jason Baron , Kees Cook , Sami Tolvanen , Ard Biesheuvel , Nicholas Piggin , Juerg Haefliger , Nicolas Saenz Julienne , "Kirill A. Shutemov" , Nadav Amit , Dan Carpenter , Chuang Wang , Yang Jihong , Petr Mladek , "Jason A. Donenfeld" , Song Liu , Julian Pidancet , Tom Lendacky , Dionna Glaze , Thomas =?utf-8?Q?Wei=C3=9Fschuh?= , Juri Lelli , Marcelo Tosatti , Yair Podemsky , Daniel Wagner , Petr Tesarik Subject: Re: [RFC PATCH v3 00/15] context_tracking,x86: Defer some IPIs until a user->kernel transition In-Reply-To: <20241119114556.0949b562@gandalf.local.home> References: <20241119153502.41361-1-vschneid@redhat.com> <20241119114556.0949b562@gandalf.local.home> Date: Tue, 19 Nov 2024 23:51:52 +0100 Message-ID: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On 19/11/24 11:45, Steven Rostedt wrote: > On Tue, 19 Nov 2024 16:34:47 +0100 > Valentin Schneider wrote: > >> Context >> ======= >> >> We've observed within Red Hat that isolated, NOHZ_FULL CPUs running a >> pure-userspace application get regularly interrupted by IPIs sent from >> housekeeping CPUs. Those IPIs are caused by activity on the housekeeping CPUs >> leading to various on_each_cpu() calls, e.g.: > > FYI, > > Sending a patch series at the start of the merge window is likely going to > get ignored. > > Care to resend after rc1 is released? Or at least ping about it. > Heh, I was so far down "stop rewriting changelogs for the Nth time, get it in a decent shape and send it out" that I forgot about this "small little detail". Thanks for the reminder.