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McKenney" Cc: Ankur Arora , linux-kernel@vger.kernel.org, tglx@linutronix.de, torvalds@linux-foundation.org, rostedt@goodmis.org, mark.rutland@arm.com, juri.lelli@redhat.com, joel@joelfernandes.org, raghavendra.kt@amd.com, sshegde@linux.ibm.com, boris.ostrovsky@oracle.com, konrad.wilk@oracle.com, Ingo Molnar , Vincent Guittot Subject: Re: [PATCH v2 16/35] preempt,rcu: warn on PREEMPT_RCU=n, preempt=full Message-ID: <20240606115325.GD8774@noisy.programming.kicks-ass.net> References: <20240528003521.979836-1-ankur.a.arora@oracle.com> <20240528003521.979836-17-ankur.a.arora@oracle.com> <20240529081404.GI26599@noisy.programming.kicks-ass.net> <8734py6gvq.fsf@oracle.com> 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: On Thu, May 30, 2024 at 04:20:26PM -0700, Paul E. McKenney wrote: > My selfish motivation here is to avoid testing this combination unless > and until someone actually has a good use for it. That doesn't make sense, the whole LAZY thing is fundamentally identical to FULL, except it sometimes delays the preemption a wee bit. But all the preemption scenarios from FULL are possible. As such, it makes far more sense to only test FULL.