PM / OPP: Assert RCU lock in exported functions (04bf1c7f) · Commits · 戴 / test

Add lockdep asserts for holding the RCU lock when calling dev_pm_opp_get_freq() and dev_pm_opp_get_voltage() to aid in detecting RCU misuses. These are called often after dev_pm_opp_find_freq_ceil/exact() which already asserts for RCU lock. However one could make an error by releasing lock too early - just after dev_pm_opp_find_freq_ceil(). Signed-off-by:

Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by:

Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/base/power/opp.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -169,6 +169,8 @@ unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
		struct dev_pm_opp *tmp_opp;
		unsigned long v = 0;

		opp_rcu_lockdep_assert();

		tmp_opp = rcu_dereference(opp);
		if (unlikely(IS_ERR_OR_NULL(tmp_opp)) \|\| !tmp_opp->available)
		pr_err("%s: Invalid parameters\n", __func__);
		@@ -199,6 +201,8 @@ unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp)
		struct dev_pm_opp *tmp_opp;
		unsigned long f = 0;

		opp_rcu_lockdep_assert();

		tmp_opp = rcu_dereference(opp);
		if (unlikely(IS_ERR_OR_NULL(tmp_opp)) \|\| !tmp_opp->available)
		pr_err("%s: Invalid parameters\n", __func__);

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