From patchwork Thu Jan 4 17:15:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukasz Luba X-Patchwork-Id: 761029 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A41DE2E629; Thu, 4 Jan 2024 17:15:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3D0271007; Thu, 4 Jan 2024 09:16:09 -0800 (PST) Received: from e129166.arm.com (unknown [10.57.88.128]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id BDE523F64C; Thu, 4 Jan 2024 09:15:20 -0800 (PST) From: Lukasz Luba To: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, rafael@kernel.org Cc: lukasz.luba@arm.com, dietmar.eggemann@arm.com, rui.zhang@intel.com, amit.kucheria@verdurent.com, amit.kachhap@gmail.com, daniel.lezcano@linaro.org, viresh.kumar@linaro.org, len.brown@intel.com, pavel@ucw.cz, mhiramat@kernel.org, qyousef@layalina.io, wvw@google.com Subject: [PATCH v6 12/23] PM: EM: Add helpers to read under RCU lock the EM table Date: Thu, 4 Jan 2024 17:15:42 +0000 Message-Id: <20240104171553.2080674-13-lukasz.luba@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240104171553.2080674-1-lukasz.luba@arm.com> References: <20240104171553.2080674-1-lukasz.luba@arm.com> Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 To use the runtime modifiable EM table there is a need to use RCU read locking properly. Add helper functions for the device drivers and frameworks to make sure it's done properly. Signed-off-by: Lukasz Luba --- include/linux/energy_model.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/include/linux/energy_model.h b/include/linux/energy_model.h index f33257ed83fd..cfaf5d8b1aad 100644 --- a/include/linux/energy_model.h +++ b/include/linux/energy_model.h @@ -338,6 +338,20 @@ static inline int em_pd_nr_perf_states(struct em_perf_domain *pd) return pd->nr_perf_states; } +static inline struct em_perf_state *em_get_table(struct em_perf_domain *pd) +{ + struct em_perf_table __rcu *table; + + rcu_read_lock(); + table = rcu_dereference(pd->em_table); + return table->state; +} + +static inline void em_put_table(void) +{ + rcu_read_unlock(); +} + #else struct em_data_callback {}; #define EM_ADV_DATA_CB(_active_power_cb, _cost_cb) { } @@ -384,6 +398,11 @@ int em_dev_update_perf_domain(struct device *dev, { return -EINVAL; } +static inline struct em_perf_state *em_get_table(struct em_perf_domain *pd) +{ + return NULL; +} +static inline void em_put_table(void) {} #endif #endif