linux-kernel - Re: [PATCH 4/4] PM / Domains: Propagate performance state updates

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Date:   Wed, 21 Nov 2018 12:06:46 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Rajendra Nayak <rnayak@...eaurora.org>
Cc:     ulf.hansson@...aro.org, "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Kevin Hilman <khilman@...nel.org>,
        Len Brown <len.brown@...el.com>, Pavel Machek <pavel@....cz>,
        linux-pm@...r.kernel.org,
        Vincent Guittot <vincent.guittot@...aro.org>,
        Stephen Boyd <sboyd@...nel.org>, Nishanth Menon <nm@...com>,
        niklas.cassel@...aro.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 4/4] PM / Domains: Propagate performance state updates

On 21-11-18, 11:12, Rajendra Nayak wrote:
> And the reason for that seems to be that we update the genpd status to GPD_STATE_ACTIVE
> *after* we try to set the performance state, so we always hit this check which bails out
> thinking the genpd is not ON.

Thanks for looking at it. Here is the (untested) fix, please try it
out.

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 84c13695af65..92be4a224b45 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -250,9 +250,6 @@ static int _genpd_set_performance_state(struct generic_pm_domain *genpd,
        unsigned int mstate;
        int ret;
 
-       if (!genpd_status_on(genpd))
-               goto out;
-
        /* Propagate to masters of genpd */
        list_for_each_entry(link, &genpd->slave_links, slave_node) {
                master = link->master;
@@ -286,7 +283,6 @@ static int _genpd_set_performance_state(struct generic_pm_domain *genpd,
        if (ret)
                goto err;
 
-out:
        genpd->performance_state = state;
        return 0;
 
@@ -361,6 +357,11 @@ static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd,
                return 0;
 
 update_state:
+       if (!genpd_status_on(genpd)) {
+               genpd->performance_state = state;
+               return 0;
+       }
+
        return _genpd_set_performance_state(genpd, state, depth);
 }

-- 
viresh