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Wysocki" , Boqun Feng , Thomas Gleixner , Steven Rostedt , "Christophe Leroy (CS GROUP)" , Kieran Bingham , Ben Segall , Michael Ellerman , Ingo Molnar , Vincent Guittot , Juri Lelli , Neeraj Upadhyay , Xin Zhao , Madhavan Srinivasan , Mel Gorman , Valentin Schneider , Christian Borntraeger , Jan Kiszka , linuxppc-dev@lists.ozlabs.org, "Paul E . McKenney" , Viresh Kumar , Anna-Maria Behnsen , Uladzislau Rezki , Dietmar Eggemann , Heiko Carstens , linux-pm@vger.kernel.org, Alexander Gordeev , Sven Schnelle , Vasily Gorbik , Joel Fernandes , Nicholas Piggin , linux-s390@vger.kernel.org, Peter Zijlstra Subject: Re: [PATCH 00/15] tick/sched: Refactor idle cputime accounting Message-ID: References: <20260116145208.87445-1-frederic@kernel.org> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Le Tue, Jan 20, 2026 at 06:12:08PM +0530, Shrikanth Hegde a écrit : > > Hi Frederic. > > On 1/16/26 8:27 PM, Frederic Weisbecker wrote: > > I forgot to mention I haven't yet tested CONFIG_VIRT_CPU_ACCOUNTING_NATIVE > > (s390 and powerpc). > > > > Thanks. > > > tl;dr > > I ran this on powerNV(Non virtualized) with 144 CPUs with below config. (default ones) > Patch *breaks* the cpu idle stats most of the time. idle values are wrong. Right I somehow lost the TS_FLAG_INIDLE setting in tick_nohz_idle_enter(), which ruins the whole thing. You probably think I should have detected that with light testing and you're right. Not checking dmesg was a bit sloppy from my end... I'm fixing that and will send a v2 soonish. Thanks a lot for testing! -- Frederic Weisbecker SUSE Labs