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Wysocki" , Alexander Gordeev , Anna-Maria Behnsen , Ben Segall , Boqun Feng , Christian Borntraeger , Dietmar Eggemann , Heiko Carstens , Ingo Molnar , Jan Kiszka , Joel Fernandes , Juri Lelli , Kieran Bingham , Madhavan Srinivasan , Mel Gorman , Michael Ellerman , Neeraj Upadhyay , Nicholas Piggin , "Paul E . McKenney" , Steven Rostedt , Sven Schnelle , Thomas Gleixner , Uladzislau Rezki , Valentin Schneider , Vasily Gorbik , Vincent Guittot , Viresh Kumar , Xin Zhao , linux-pm@vger.kernel.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH 03/15] sched/cputime: Correctly support generic vtime idle time Message-ID: <20260119130222.GU830755@noisy.programming.kicks-ass.net> References: <20260116145208.87445-1-frederic@kernel.org> <20260116145208.87445-4-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=us-ascii Content-Disposition: inline In-Reply-To: <20260116145208.87445-4-frederic@kernel.org> On Fri, Jan 16, 2026 at 03:51:56PM +0100, Frederic Weisbecker wrote: > diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c > index 8ddf74e705d3..f1d07a0276a5 100644 > --- a/kernel/time/tick-sched.c > +++ b/kernel/time/tick-sched.c > @@ -780,7 +780,7 @@ static u64 get_cpu_sleep_time_us(struct tick_sched *ts, ktime_t *sleeptime, > ktime_t now, idle; > unsigned int seq; > > - if (!tick_nohz_active) > + if (!tick_nohz_active || vtime_generic_enabled_cpu(cpu)) > return -1; > > now = ktime_get(); Is this not broken? IIUC this means that you can no longer use get_cpu_{idle,iowait}_time_us() the moment you have context tracking enabled.