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McKenney" , Neeraj Upadhyay , Josh Triplett , Boqun Feng , Uladzislau Rezki , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Zqiang , rcu@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260224230435.3390963-1-joelagnelf@nvidia.com> <20260224230435.3390963-2-joelagnelf@nvidia.com> Content-Language: en-US From: Joel Fernandes In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: BL1PR13CA0172.namprd13.prod.outlook.com (2603:10b6:208:2bd::27) To DS0PR12MB6486.namprd12.prod.outlook.com (2603:10b6:8:c5::21) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS0PR12MB6486:EE_|LV2PR12MB999096:EE_ X-MS-Office365-Filtering-Correlation-Id: 14e2615c-4039-42b1-e327-08de7a1041af X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|376014|366016|7416014; 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>> } >> >> -int rcu_nocb_cpu_deoffload(int cpu) >> -{ >> - struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); >> - int ret = 0; >> - >> - cpus_read_lock(); >> - mutex_lock(&rcu_state.nocb_mutex); >> - if (rcu_rdp_is_offloaded(rdp)) { >> - if (!cpu_online(cpu)) { >> - ret = rcu_nocb_rdp_deoffload(rdp); >> - if (!ret) >> - cpumask_clear_cpu(cpu, rcu_nocb_mask); >> - } else { >> - pr_info("NOCB: Cannot CB-deoffload online CPU %d\n", rdp->cpu); >> - ret = -EINVAL; >> - } >> - } >> - mutex_unlock(&rcu_state.nocb_mutex); >> - cpus_read_unlock(); >> - >> - return ret; >> -} >> -EXPORT_SYMBOL_GPL(rcu_nocb_cpu_deoffload); >> - >> static bool rcu_nocb_rdp_offload_wait_cond(struct rcu_data *rdp) >> { >> unsigned long flags; >> @@ -1149,27 +1125,54 @@ static int rcu_nocb_rdp_offload(struct rcu_data *rdp) >> return 0; >> } >> >> +/* Common helper for CPU offload/deoffload operations. */ >> +static int rcu_nocb_cpu_toggle_offload(int cpu, bool offload) >> +{ >> + struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); >> + bool currently_offloaded; >> + int ret = 0; >> + >> + cpus_read_lock(); >> + mutex_lock(&rcu_state.nocb_mutex); >> + >> + currently_offloaded = rcu_rdp_is_offloaded(rdp); > > Do we really need that extra variable? No we don't need it, fixed. > Reviewed-by: Frederic Weisbecker > Thanks! -- Joel Fernandes