On Thu, 2024-05-30 at 13:53 +0300, Imre Deak wrote:
> Commit dd839aa857eb ("drm/i915: Fix incorrect assert about pending
> power domain async-put work")
>
> fixed the assert about a pending work dropping a display power
> reference
> asynchronously, leading to the
>
> drm_WARN_ON(!queue_delayed_work(&power_domains->async_put_work));
>
> warn next time around a power reference was put asynchronously, due
> to a
> stale instance of the work still being pending. However the fix
> didn't
> consider the case where multiple power reference was acquired and
> put,
> requiring the work to requeue itself. Extend the fix for this case as
> well canceling the pending instance of the work before it requeues
> itself.
Reviewed-by: Jouni Högander <jouni.hogander@xxxxxxxxx>
>
> Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/10915
> Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_display_power.c | 12 ++++++------
> 1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c
> b/drivers/gpu/drm/i915/display/intel_display_power.c
> index 34b6d843bc9ef..8c49ac053dfb0 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_power.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_power.c
> @@ -675,6 +675,12 @@ intel_display_power_put_async_work(struct
> work_struct *work)
> release_async_put_domains(power_domains,
> &power_domains-
> >async_put_domains[0]);
>
> + /*
> + * Cancel the work that got queued after this one got
> dequeued,
> + * since here we released the corresponding async-put
> reference.
> + */
> + cancel_async_put_work(power_domains, false);
> +
> /* Requeue the work if more domains were async put meanwhile.
> */
> if (!bitmap_empty(power_domains->async_put_domains[1].bits,
> POWER_DOMAIN_NUM)) {
> bitmap_copy(power_domains->async_put_domains[0].bits,
> @@ -686,12 +692,6 @@ intel_display_power_put_async_work(struct
> work_struct *work)
>
> fetch_and_zero(&new_work_wakeref),
> power_domains-
> >async_put_next_delay);
> power_domains->async_put_next_delay = 0;
> - } else {
> - /*
> - * Cancel the work that got queued after this one got
> dequeued,
> - * since here we released the corresponding async-put
> reference.
> - */
> - cancel_async_put_work(power_domains, false);
> }
>
> out_verify:
