Messages in this thread | | | Date | Mon, 18 Sep 2023 12:11:14 +0100 | From | Marc Zyngier <> | Subject | Re: [PATCH] clocksource/drivers/arm_arch_timer: Initialize evtstrm after finalizing cpucaps |
| |
On Thu, 07 Sep 2023 14:34:10 +0100, Mark Rutland <mark.rutland@arm.com> wrote: > > We attempt to initialize each CPU's arch_timer event stream in > arch_timer_evtstrm_enable(), which we call from the > arch_timer_starting_cpu() cpu hotplug callback which is registered early > in boot. As this is registered before we initialize the system cpucaps, > the test for ARM64_HAS_ECV will always be false for CPUs present at boot > time, and will only be taken into account for CPUs onlined late > (including those which are hotplugged out and in again). > > Due to this, CPUs present and boot time may not use the intended divider > and scale factor to generate the event stream, and may differ from other > CPUs. > > Correct this by only initializing the event stream after cpucaps have been > finalized, registering a separate CPU hotplug callback for the event stream > configuration. Since the caps must be finalized by this point, use > spus_have_final_cap() to verify this. > > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Cc: Daniel Lezcano <daniel.lezcano@linaro.org> > Cc: Marc Zyngier <maz@kernel.org> > Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <maz@kernel.org>
M.
-- Without deviation from the norm, progress is not possible.
| |