On Wed, Jul 6, 2022 at 8:54 AM Abel Vesa <abel.vesa@xxxxxxxxxx> wrote:
>
> In case of a cyclic dependency, if the supplier is not yet available,
> the parent of the supplier is checked for dependency. But if there are
> more than one suppliers with the same parent, the first check returns
> true while the next ones skip that specific link entirely because of
> having DL_FLAG_MANAGED and DL_FLAG_SYNC_STATE_ONLY set, which is what
> the relaxing of the link does. But if we check for the target being
> a consumer before the check for those flags, we can check as many
> times as needed the same link and it will always return true, This is
> safe to do, since the relaxing of the link will be done only once
> because those flags will be set and it will bail early.
>
> Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx>
> ---
> drivers/base/core.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index 753e7cca0f40..2c3b860dfe80 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -297,13 +297,13 @@ int device_is_dependent(struct device *dev, void *target)
> return ret;
>
> list_for_each_entry(link, &dev->links.consumers, s_node) {
> + if (link->consumer == target)
> + return 1;
> +
> if ((link->flags & ~DL_FLAG_INFERRED) ==
> (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
> continue;
Thanks for trying to fix this issue, but I'll have to Nack this patch.
The whole point of the SYNC_STATE_ONLY flag is to allow cycles. It's
needed to maintain correctness of sync_state(). I think I described
those in the commit text that added the SYNC_STATE_ONLY flag. Check it
out if you are interested. So this change of yours will break
sync_state() functionality.
There's a bunch of nuance to fixing the dual cycle issue and I don't
mind fixing this myself in a week or two if you can wait.
Thanks,
Saravana
>
> - if (link->consumer == target)
> - return 1;
> -
> ret = device_is_dependent(link->consumer, target);
> if (ret)
> break;
> --
> 2.34.3
>
