Re: [PATCH 3/5] tick/broadcast: Prefer per-cpu oneshot wakeup timers to broadcast
From: Will Deacon <will@kernel.org>
Date: 2021-05-21 11:25:12
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On Fri, May 21, 2021 at 05:25:41AM +0300, Mika Penttilä wrote:
On 20.5.2021 21.47, Will Deacon wrote:quoted
/* * Conditionally install/replace broadcast device */ -void tick_install_broadcast_device(struct clock_event_device *dev) +void tick_install_broadcast_device(struct clock_event_device *dev, int cpu) { struct clock_event_device *cur = tick_broadcast_device.evtdev; + if (tick_set_oneshot_wakeup_device(dev, cpu)) + return; + if (!tick_check_broadcast_device(cur, dev)) return;Does this disable hpet registering as a global broadcast device on x86 ? I think it starts with cpumask = cpu0 so it qualifies for a percpu wakeup timer.
Well spotted, I think you're probably right. I'll try to reproduce on my laptop to confirm, but I hadn't noticed the tricks played with the cpumask on x86. I'll probably need to rework things so that we install the broadcast timer first, but prefer global devices. Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel