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kernel/padata.c
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/* * padata.c - generic interface to process data streams in parallel * * Copyright (C) 2008, 2009 secunet Security Networks AG * Copyright (C) 2008, 2009 Steffen Klassert <steffen.klassert@secunet.com> * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. */ #include <linux/module.h> #include <linux/cpumask.h> #include <linux/err.h> #include <linux/cpu.h> #include <linux/padata.h> #include <linux/mutex.h> #include <linux/sched.h> |
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#include <linux/slab.h> |
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#include <linux/sysfs.h> |
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#include <linux/rcupdate.h> |
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#define MAX_SEQ_NR (INT_MAX - NR_CPUS) |
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#define MAX_OBJ_NUM 1000 |
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static int padata_index_to_cpu(struct parallel_data *pd, int cpu_index) { int cpu, target_cpu; |
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target_cpu = cpumask_first(pd->cpumask.pcpu); |
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for (cpu = 0; cpu < cpu_index; cpu++) |
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target_cpu = cpumask_next(target_cpu, pd->cpumask.pcpu); |
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return target_cpu; } static int padata_cpu_hash(struct padata_priv *padata) { int cpu_index; struct parallel_data *pd; pd = padata->pd; /* * Hash the sequence numbers to the cpus by taking * seq_nr mod. number of cpus in use. */ |
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cpu_index = padata->seq_nr % cpumask_weight(pd->cpumask.pcpu); |
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return padata_index_to_cpu(pd, cpu_index); } |
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static void padata_parallel_worker(struct work_struct *parallel_work) |
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{ |
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struct padata_parallel_queue *pqueue; |
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struct parallel_data *pd; struct padata_instance *pinst; LIST_HEAD(local_list); local_bh_disable(); |
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pqueue = container_of(parallel_work, struct padata_parallel_queue, work); pd = pqueue->pd; |
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pinst = pd->pinst; |
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spin_lock(&pqueue->parallel.lock); list_replace_init(&pqueue->parallel.list, &local_list); spin_unlock(&pqueue->parallel.lock); |
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while (!list_empty(&local_list)) { struct padata_priv *padata; padata = list_entry(local_list.next, struct padata_priv, list); list_del_init(&padata->list); padata->parallel(padata); } local_bh_enable(); } |
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/** |
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* padata_do_parallel - padata parallelization function * * @pinst: padata instance * @padata: object to be parallelized * @cb_cpu: cpu the serialization callback function will run on, |
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* must be in the serial cpumask of padata(i.e. cpumask.cbcpu). |
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* * The parallelization callback function will run with BHs off. * Note: Every object which is parallelized by padata_do_parallel * must be seen by padata_do_serial. */ int padata_do_parallel(struct padata_instance *pinst, struct padata_priv *padata, int cb_cpu) { int target_cpu, err; |
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struct padata_parallel_queue *queue; |
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struct parallel_data *pd; rcu_read_lock_bh(); pd = rcu_dereference(pinst->pd); |
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err = -EINVAL; |
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if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID) |
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goto out; |
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if (!cpumask_test_cpu(cb_cpu, pd->cpumask.cbcpu)) |
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goto out; err = -EBUSY; if ((pinst->flags & PADATA_RESET)) goto out; if (atomic_read(&pd->refcnt) >= MAX_OBJ_NUM) goto out; |
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err = 0; |
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atomic_inc(&pd->refcnt); padata->pd = pd; padata->cb_cpu = cb_cpu; if (unlikely(atomic_read(&pd->seq_nr) == pd->max_seq_nr)) atomic_set(&pd->seq_nr, -1); padata->seq_nr = atomic_inc_return(&pd->seq_nr); target_cpu = padata_cpu_hash(padata); |
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queue = per_cpu_ptr(pd->pqueue, target_cpu); |
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spin_lock(&queue->parallel.lock); list_add_tail(&padata->list, &queue->parallel.list); spin_unlock(&queue->parallel.lock); |
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queue_work_on(target_cpu, pinst->wq, &queue->work); |
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out: rcu_read_unlock_bh(); return err; } EXPORT_SYMBOL(padata_do_parallel); |
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/* * padata_get_next - Get the next object that needs serialization. * * Return values are: * * A pointer to the control struct of the next object that needs * serialization, if present in one of the percpu reorder queues. * * NULL, if all percpu reorder queues are empty. * * -EINPROGRESS, if the next object that needs serialization will * be parallel processed by another cpu and is not yet present in * the cpu's reorder queue. * * -ENODATA, if this cpu has to do the parallel processing for * the next object. */ |
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static struct padata_priv *padata_get_next(struct parallel_data *pd) { |
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int cpu, num_cpus; int next_nr, next_index; |
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struct padata_parallel_queue *queue, *next_queue; |
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struct padata_priv *padata; struct padata_list *reorder; |
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num_cpus = cpumask_weight(pd->cpumask.pcpu); |
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/* * Calculate the percpu reorder queue and the sequence * number of the next object. */ next_nr = pd->processed; next_index = next_nr % num_cpus; cpu = padata_index_to_cpu(pd, next_index); |
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next_queue = per_cpu_ptr(pd->pqueue, cpu); |
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if (unlikely(next_nr > pd->max_seq_nr)) { next_nr = next_nr - pd->max_seq_nr - 1; next_index = next_nr % num_cpus; cpu = padata_index_to_cpu(pd, next_index); |
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next_queue = per_cpu_ptr(pd->pqueue, cpu); |
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pd->processed = 0; |
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} padata = NULL; |
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reorder = &next_queue->reorder; if (!list_empty(&reorder->list)) { padata = list_entry(reorder->list.next, struct padata_priv, list); |
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BUG_ON(next_nr != padata->seq_nr); |
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spin_lock(&reorder->lock); list_del_init(&padata->list); atomic_dec(&pd->reorder_objects); spin_unlock(&reorder->lock); |
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pd->processed++; |
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goto out; } |
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queue = per_cpu_ptr(pd->pqueue, smp_processor_id()); |
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if (queue->cpu_index == next_queue->cpu_index) { |
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padata = ERR_PTR(-ENODATA); goto out; } padata = ERR_PTR(-EINPROGRESS); out: return padata; } static void padata_reorder(struct parallel_data *pd) { struct padata_priv *padata; |
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struct padata_serial_queue *squeue; |
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struct padata_instance *pinst = pd->pinst; |
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/* * We need to ensure that only one cpu can work on dequeueing of * the reorder queue the time. Calculating in which percpu reorder * queue the next object will arrive takes some time. A spinlock * would be highly contended. Also it is not clear in which order * the objects arrive to the reorder queues. So a cpu could wait to * get the lock just to notice that there is nothing to do at the * moment. Therefore we use a trylock and let the holder of the lock * care for all the objects enqueued during the holdtime of the lock. */ |
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if (!spin_trylock_bh(&pd->lock)) |
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return; |
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while (1) { padata = padata_get_next(pd); |
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/* * All reorder queues are empty, or the next object that needs * serialization is parallel processed by another cpu and is * still on it's way to the cpu's reorder queue, nothing to * do for now. */ |
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if (!padata || PTR_ERR(padata) == -EINPROGRESS) break; |
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/* * This cpu has to do the parallel processing of the next * object. It's waiting in the cpu's parallelization queue, |
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* so exit immediately. |
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*/ |
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if (PTR_ERR(padata) == -ENODATA) { |
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del_timer(&pd->timer); |
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spin_unlock_bh(&pd->lock); |
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return; |
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} |
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squeue = per_cpu_ptr(pd->squeue, padata->cb_cpu); |
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spin_lock(&squeue->serial.lock); list_add_tail(&padata->list, &squeue->serial.list); spin_unlock(&squeue->serial.lock); |
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queue_work_on(padata->cb_cpu, pinst->wq, &squeue->work); |
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} spin_unlock_bh(&pd->lock); |
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/* * The next object that needs serialization might have arrived to * the reorder queues in the meantime, we will be called again |
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* from the timer function if no one else cares for it. |
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*/ |
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if (atomic_read(&pd->reorder_objects) && !(pinst->flags & PADATA_RESET)) mod_timer(&pd->timer, jiffies + HZ); else del_timer(&pd->timer); |
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return; } |
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static void padata_reorder_timer(unsigned long arg) { struct parallel_data *pd = (struct parallel_data *)arg; padata_reorder(pd); } |
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static void padata_serial_worker(struct work_struct *serial_work) |
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{ |
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struct padata_serial_queue *squeue; |
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struct parallel_data *pd; LIST_HEAD(local_list); local_bh_disable(); |
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squeue = container_of(serial_work, struct padata_serial_queue, work); pd = squeue->pd; |
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spin_lock(&squeue->serial.lock); list_replace_init(&squeue->serial.list, &local_list); spin_unlock(&squeue->serial.lock); |
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while (!list_empty(&local_list)) { struct padata_priv *padata; padata = list_entry(local_list.next, struct padata_priv, list); list_del_init(&padata->list); padata->serial(padata); atomic_dec(&pd->refcnt); } local_bh_enable(); } |
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/** |
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* padata_do_serial - padata serialization function * * @padata: object to be serialized. * * padata_do_serial must be called for every parallelized object. * The serialization callback function will run with BHs off. */ void padata_do_serial(struct padata_priv *padata) { int cpu; |
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struct padata_parallel_queue *pqueue; |
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struct parallel_data *pd; pd = padata->pd; cpu = get_cpu(); |
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pqueue = per_cpu_ptr(pd->pqueue, cpu); |
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spin_lock(&pqueue->reorder.lock); |
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atomic_inc(&pd->reorder_objects); |
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list_add_tail(&padata->list, &pqueue->reorder.list); spin_unlock(&pqueue->reorder.lock); |
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put_cpu(); padata_reorder(pd); } EXPORT_SYMBOL(padata_do_serial); |
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static int padata_setup_cpumasks(struct parallel_data *pd, const struct cpumask *pcpumask, const struct cpumask *cbcpumask) |
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{ |
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if (!alloc_cpumask_var(&pd->cpumask.pcpu, GFP_KERNEL)) return -ENOMEM; |
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cpumask_and(pd->cpumask.pcpu, pcpumask, cpu_active_mask); if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) { free_cpumask_var(pd->cpumask.cbcpu); return -ENOMEM; } |
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cpumask_and(pd->cpumask.cbcpu, cbcpumask, cpu_active_mask); return 0; } |
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static void __padata_list_init(struct padata_list *pd_list) { INIT_LIST_HEAD(&pd_list->list); spin_lock_init(&pd_list->lock); } |
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/* Initialize all percpu queues used by serial workers */ static void padata_init_squeues(struct parallel_data *pd) { int cpu; struct padata_serial_queue *squeue; |
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for_each_cpu(cpu, pd->cpumask.cbcpu) { squeue = per_cpu_ptr(pd->squeue, cpu); squeue->pd = pd; __padata_list_init(&squeue->serial); INIT_WORK(&squeue->work, padata_serial_worker); } } |
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/* Initialize all percpu queues used by parallel workers */ static void padata_init_pqueues(struct parallel_data *pd) { int cpu_index, num_cpus, cpu; struct padata_parallel_queue *pqueue; |
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cpu_index = 0; for_each_cpu(cpu, pd->cpumask.pcpu) { pqueue = per_cpu_ptr(pd->pqueue, cpu); pqueue->pd = pd; pqueue->cpu_index = cpu_index; |
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cpu_index++; |
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__padata_list_init(&pqueue->reorder); __padata_list_init(&pqueue->parallel); INIT_WORK(&pqueue->work, padata_parallel_worker); atomic_set(&pqueue->num_obj, 0); |
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} |
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num_cpus = cpumask_weight(pd->cpumask.pcpu); |
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pd->max_seq_nr = num_cpus ? (MAX_SEQ_NR / num_cpus) * num_cpus - 1 : 0; |
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} |
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/* Allocate and initialize the internal cpumask dependend resources. */ static struct parallel_data *padata_alloc_pd(struct padata_instance *pinst, const struct cpumask *pcpumask, const struct cpumask *cbcpumask) { struct parallel_data *pd; |
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pd = kzalloc(sizeof(struct parallel_data), GFP_KERNEL); if (!pd) goto err; |
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pd->pqueue = alloc_percpu(struct padata_parallel_queue); if (!pd->pqueue) goto err_free_pd; pd->squeue = alloc_percpu(struct padata_serial_queue); if (!pd->squeue) goto err_free_pqueue; if (padata_setup_cpumasks(pd, pcpumask, cbcpumask) < 0) goto err_free_squeue; |
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padata_init_pqueues(pd); padata_init_squeues(pd); |
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setup_timer(&pd->timer, padata_reorder_timer, (unsigned long)pd); |
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atomic_set(&pd->seq_nr, -1); atomic_set(&pd->reorder_objects, 0); atomic_set(&pd->refcnt, 0); pd->pinst = pinst; spin_lock_init(&pd->lock); return pd; |
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err_free_squeue: free_percpu(pd->squeue); err_free_pqueue: free_percpu(pd->pqueue); |
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err_free_pd: kfree(pd); err: return NULL; } static void padata_free_pd(struct parallel_data *pd) { |
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free_cpumask_var(pd->cpumask.pcpu); free_cpumask_var(pd->cpumask.cbcpu); free_percpu(pd->pqueue); free_percpu(pd->squeue); |
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kfree(pd); } |
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/* Flush all objects out of the padata queues. */ |
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static void padata_flush_queues(struct parallel_data *pd) { int cpu; |
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struct padata_parallel_queue *pqueue; struct padata_serial_queue *squeue; |
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for_each_cpu(cpu, pd->cpumask.pcpu) { pqueue = per_cpu_ptr(pd->pqueue, cpu); flush_work(&pqueue->work); |
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} del_timer_sync(&pd->timer); if (atomic_read(&pd->reorder_objects)) padata_reorder(pd); |
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for_each_cpu(cpu, pd->cpumask.cbcpu) { squeue = per_cpu_ptr(pd->squeue, cpu); flush_work(&squeue->work); |
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} BUG_ON(atomic_read(&pd->refcnt) != 0); } |
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static void __padata_start(struct padata_instance *pinst) { pinst->flags |= PADATA_INIT; } |
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static void __padata_stop(struct padata_instance *pinst) { if (!(pinst->flags & PADATA_INIT)) return; pinst->flags &= ~PADATA_INIT; synchronize_rcu(); get_online_cpus(); padata_flush_queues(pinst->pd); put_online_cpus(); } |
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/* Replace the internal control structure with a new one. */ |
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static void padata_replace(struct padata_instance *pinst, struct parallel_data *pd_new) { struct parallel_data *pd_old = pinst->pd; |
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int notification_mask = 0; |
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pinst->flags |= PADATA_RESET; rcu_assign_pointer(pinst->pd, pd_new); synchronize_rcu(); |
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if (!cpumask_equal(pd_old->cpumask.pcpu, pd_new->cpumask.pcpu)) notification_mask |= PADATA_CPU_PARALLEL; if (!cpumask_equal(pd_old->cpumask.cbcpu, pd_new->cpumask.cbcpu)) notification_mask |= PADATA_CPU_SERIAL; |
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padata_flush_queues(pd_old); |
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padata_free_pd(pd_old); |
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if (notification_mask) blocking_notifier_call_chain(&pinst->cpumask_change_notifier, |
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notification_mask, &pd_new->cpumask); |
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pinst->flags &= ~PADATA_RESET; } |
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/** |
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* padata_register_cpumask_notifier - Registers a notifier that will be called * if either pcpu or cbcpu or both cpumasks change. |
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* |
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* @pinst: A poineter to padata instance * @nblock: A pointer to notifier block. |
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*/ |
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int padata_register_cpumask_notifier(struct padata_instance *pinst, struct notifier_block *nblock) |
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{ |
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return blocking_notifier_chain_register(&pinst->cpumask_change_notifier, nblock); } EXPORT_SYMBOL(padata_register_cpumask_notifier); /** * padata_unregister_cpumask_notifier - Unregisters cpumask notifier * registered earlier using padata_register_cpumask_notifier * * @pinst: A pointer to data instance. * @nlock: A pointer to notifier block. */ int padata_unregister_cpumask_notifier(struct padata_instance *pinst, struct notifier_block *nblock) { return blocking_notifier_chain_unregister( &pinst->cpumask_change_notifier, nblock); } EXPORT_SYMBOL(padata_unregister_cpumask_notifier); |
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/* If cpumask contains no active cpu, we mark the instance as invalid. */ static bool padata_validate_cpumask(struct padata_instance *pinst, const struct cpumask *cpumask) { if (!cpumask_intersects(cpumask, cpu_active_mask)) { pinst->flags |= PADATA_INVALID; return false; } pinst->flags &= ~PADATA_INVALID; return true; } |
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static int __padata_set_cpumasks(struct padata_instance *pinst, cpumask_var_t pcpumask, cpumask_var_t cbcpumask) { int valid; |
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struct parallel_data *pd; |
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560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 |
valid = padata_validate_cpumask(pinst, pcpumask); if (!valid) { __padata_stop(pinst); goto out_replace; } valid = padata_validate_cpumask(pinst, cbcpumask); if (!valid) __padata_stop(pinst); out_replace: pd = padata_alloc_pd(pinst, pcpumask, cbcpumask); if (!pd) return -ENOMEM; cpumask_copy(pinst->cpumask.pcpu, pcpumask); cpumask_copy(pinst->cpumask.cbcpu, cbcpumask); padata_replace(pinst, pd); if (valid) __padata_start(pinst); return 0; } /** * padata_set_cpumasks - Set both parallel and serial cpumasks. The first * one is used by parallel workers and the second one * by the wokers doing serialization. * * @pinst: padata instance * @pcpumask: the cpumask to use for parallel workers * @cbcpumask: the cpumsak to use for serial workers */ int padata_set_cpumasks(struct padata_instance *pinst, cpumask_var_t pcpumask, cpumask_var_t cbcpumask) { int err; |
16295bec6
|
600 |
|
16295bec6
|
601 |
mutex_lock(&pinst->lock); |
65ff577e6
|
602 |
get_online_cpus(); |
16295bec6
|
603 |
|
65ff577e6
|
604 605 606 607 608 609 610 611 612 |
err = __padata_set_cpumasks(pinst, pcpumask, cbcpumask); put_online_cpus(); mutex_unlock(&pinst->lock); return err; } EXPORT_SYMBOL(padata_set_cpumasks); |
e15bacbeb
|
613 614 615 |
/** * padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value * equivalent to @cpumask. |
16295bec6
|
616 617 |
* * @pinst: padata instance |
e15bacbeb
|
618 619 |
* @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding * to parallel and serial cpumasks respectively. |
16295bec6
|
620 621 |
* @cpumask: the cpumask to use */ |
e15bacbeb
|
622 623 624 625 |
int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type, cpumask_var_t cpumask) { struct cpumask *serial_mask, *parallel_mask; |
65ff577e6
|
626 627 628 |
int err = -EINVAL; mutex_lock(&pinst->lock); |
6751fb3c0
|
629 |
get_online_cpus(); |
e15bacbeb
|
630 631 632 633 634 635 636 637 638 639 |
switch (cpumask_type) { case PADATA_CPU_PARALLEL: serial_mask = pinst->cpumask.cbcpu; parallel_mask = cpumask; break; case PADATA_CPU_SERIAL: parallel_mask = pinst->cpumask.pcpu; serial_mask = cpumask; break; default: |
65ff577e6
|
640 |
goto out; |
16295bec6
|
641 |
} |
65ff577e6
|
642 |
err = __padata_set_cpumasks(pinst, parallel_mask, serial_mask); |
16295bec6
|
643 644 |
out: |
6751fb3c0
|
645 |
put_online_cpus(); |
16295bec6
|
646 647 648 649 650 651 652 653 654 655 656 |
mutex_unlock(&pinst->lock); return err; } EXPORT_SYMBOL(padata_set_cpumask); static int __padata_add_cpu(struct padata_instance *pinst, int cpu) { struct parallel_data *pd; if (cpumask_test_cpu(cpu, cpu_active_mask)) { |
e15bacbeb
|
657 658 |
pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu, pinst->cpumask.cbcpu); |
16295bec6
|
659 660 661 662 |
if (!pd) return -ENOMEM; padata_replace(pinst, pd); |
33e544506
|
663 |
|
e15bacbeb
|
664 665 |
if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) && padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) |
33e544506
|
666 |
__padata_start(pinst); |
16295bec6
|
667 668 669 670 |
} return 0; } |
e15bacbeb
|
671 672 673 |
/** * padata_add_cpu - add a cpu to one or both(parallel and serial) * padata cpumasks. |
16295bec6
|
674 675 676 |
* * @pinst: padata instance * @cpu: cpu to add |
e15bacbeb
|
677 678 679 680 |
* @mask: bitmask of flags specifying to which cpumask @cpu shuld be added. * The @mask may be any combination of the following flags: * PADATA_CPU_SERIAL - serial cpumask * PADATA_CPU_PARALLEL - parallel cpumask |
16295bec6
|
681 |
*/ |
e15bacbeb
|
682 683 |
int padata_add_cpu(struct padata_instance *pinst, int cpu, int mask) |
16295bec6
|
684 685 |
{ int err; |
e15bacbeb
|
686 687 |
if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL))) return -EINVAL; |
16295bec6
|
688 |
mutex_lock(&pinst->lock); |
6751fb3c0
|
689 |
get_online_cpus(); |
e15bacbeb
|
690 691 692 693 |
if (mask & PADATA_CPU_SERIAL) cpumask_set_cpu(cpu, pinst->cpumask.cbcpu); if (mask & PADATA_CPU_PARALLEL) cpumask_set_cpu(cpu, pinst->cpumask.pcpu); |
16295bec6
|
694 |
err = __padata_add_cpu(pinst, cpu); |
6751fb3c0
|
695 |
put_online_cpus(); |
16295bec6
|
696 697 698 699 700 701 702 703 704 |
mutex_unlock(&pinst->lock); return err; } EXPORT_SYMBOL(padata_add_cpu); static int __padata_remove_cpu(struct padata_instance *pinst, int cpu) { |
33e544506
|
705 |
struct parallel_data *pd = NULL; |
16295bec6
|
706 707 |
if (cpumask_test_cpu(cpu, cpu_online_mask)) { |
33e544506
|
708 |
|
e15bacbeb
|
709 |
if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) || |
b89661dff
|
710 |
!padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) |
33e544506
|
711 |
__padata_stop(pinst); |
33e544506
|
712 |
|
e15bacbeb
|
713 714 |
pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu, pinst->cpumask.cbcpu); |
16295bec6
|
715 716 717 718 719 720 721 722 |
if (!pd) return -ENOMEM; padata_replace(pinst, pd); } return 0; } |
e15bacbeb
|
723 |
/** |
25985edce
|
724 |
* padata_remove_cpu - remove a cpu from the one or both(serial and parallel) |
e15bacbeb
|
725 |
* padata cpumasks. |
16295bec6
|
726 727 728 |
* * @pinst: padata instance * @cpu: cpu to remove |
e15bacbeb
|
729 730 731 732 |
* @mask: bitmask specifying from which cpumask @cpu should be removed * The @mask may be any combination of the following flags: * PADATA_CPU_SERIAL - serial cpumask * PADATA_CPU_PARALLEL - parallel cpumask |
16295bec6
|
733 |
*/ |
e15bacbeb
|
734 |
int padata_remove_cpu(struct padata_instance *pinst, int cpu, int mask) |
16295bec6
|
735 736 |
{ int err; |
e15bacbeb
|
737 738 |
if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL))) return -EINVAL; |
16295bec6
|
739 |
mutex_lock(&pinst->lock); |
6751fb3c0
|
740 |
get_online_cpus(); |
e15bacbeb
|
741 742 743 744 |
if (mask & PADATA_CPU_SERIAL) cpumask_clear_cpu(cpu, pinst->cpumask.cbcpu); if (mask & PADATA_CPU_PARALLEL) cpumask_clear_cpu(cpu, pinst->cpumask.pcpu); |
16295bec6
|
745 |
err = __padata_remove_cpu(pinst, cpu); |
6751fb3c0
|
746 |
put_online_cpus(); |
16295bec6
|
747 748 749 750 751 752 |
mutex_unlock(&pinst->lock); return err; } EXPORT_SYMBOL(padata_remove_cpu); |
0198ffd13
|
753 |
/** |
16295bec6
|
754 755 756 757 |
* padata_start - start the parallel processing * * @pinst: padata instance to start */ |
4c8791702
|
758 |
int padata_start(struct padata_instance *pinst) |
16295bec6
|
759 |
{ |
4c8791702
|
760 |
int err = 0; |
16295bec6
|
761 |
mutex_lock(&pinst->lock); |
4c8791702
|
762 763 764 765 766 |
if (pinst->flags & PADATA_INVALID) err =-EINVAL; __padata_start(pinst); |
16295bec6
|
767 |
mutex_unlock(&pinst->lock); |
4c8791702
|
768 769 |
return err; |
16295bec6
|
770 771 |
} EXPORT_SYMBOL(padata_start); |
0198ffd13
|
772 |
/** |
16295bec6
|
773 774 775 776 777 778 |
* padata_stop - stop the parallel processing * * @pinst: padata instance to stop */ void padata_stop(struct padata_instance *pinst) { |
16295bec6
|
779 |
mutex_lock(&pinst->lock); |
ee8365551
|
780 |
__padata_stop(pinst); |
16295bec6
|
781 782 783 |
mutex_unlock(&pinst->lock); } EXPORT_SYMBOL(padata_stop); |
e2cb2f1c2
|
784 |
#ifdef CONFIG_HOTPLUG_CPU |
e15bacbeb
|
785 786 787 788 789 790 |
static inline int pinst_has_cpu(struct padata_instance *pinst, int cpu) { return cpumask_test_cpu(cpu, pinst->cpumask.pcpu) || cpumask_test_cpu(cpu, pinst->cpumask.cbcpu); } |
975d26035
|
791 792 |
static int padata_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) |
16295bec6
|
793 794 795 796 797 798 799 800 801 802 |
{ int err; struct padata_instance *pinst; int cpu = (unsigned long)hcpu; pinst = container_of(nfb, struct padata_instance, cpu_notifier); switch (action) { case CPU_ONLINE: case CPU_ONLINE_FROZEN: |
e15bacbeb
|
803 |
if (!pinst_has_cpu(pinst, cpu)) |
16295bec6
|
804 805 806 807 808 |
break; mutex_lock(&pinst->lock); err = __padata_add_cpu(pinst, cpu); mutex_unlock(&pinst->lock); if (err) |
80b5184cc
|
809 |
return notifier_from_errno(err); |
16295bec6
|
810 811 812 813 |
break; case CPU_DOWN_PREPARE: case CPU_DOWN_PREPARE_FROZEN: |
e15bacbeb
|
814 |
if (!pinst_has_cpu(pinst, cpu)) |
16295bec6
|
815 816 817 818 819 |
break; mutex_lock(&pinst->lock); err = __padata_remove_cpu(pinst, cpu); mutex_unlock(&pinst->lock); if (err) |
80b5184cc
|
820 |
return notifier_from_errno(err); |
16295bec6
|
821 822 823 824 |
break; case CPU_UP_CANCELED: case CPU_UP_CANCELED_FROZEN: |
e15bacbeb
|
825 |
if (!pinst_has_cpu(pinst, cpu)) |
16295bec6
|
826 827 828 829 830 831 832 |
break; mutex_lock(&pinst->lock); __padata_remove_cpu(pinst, cpu); mutex_unlock(&pinst->lock); case CPU_DOWN_FAILED: case CPU_DOWN_FAILED_FROZEN: |
e15bacbeb
|
833 |
if (!pinst_has_cpu(pinst, cpu)) |
16295bec6
|
834 835 836 837 838 839 840 841 |
break; mutex_lock(&pinst->lock); __padata_add_cpu(pinst, cpu); mutex_unlock(&pinst->lock); } return NOTIFY_OK; } |
e2cb2f1c2
|
842 |
#endif |
16295bec6
|
843 |
|
5e017dc3f
|
844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 |
static void __padata_free(struct padata_instance *pinst) { #ifdef CONFIG_HOTPLUG_CPU unregister_hotcpu_notifier(&pinst->cpu_notifier); #endif padata_stop(pinst); padata_free_pd(pinst->pd); free_cpumask_var(pinst->cpumask.pcpu); free_cpumask_var(pinst->cpumask.cbcpu); kfree(pinst); } #define kobj2pinst(_kobj) \ container_of(_kobj, struct padata_instance, kobj) #define attr2pentry(_attr) \ container_of(_attr, struct padata_sysfs_entry, attr) static void padata_sysfs_release(struct kobject *kobj) { struct padata_instance *pinst = kobj2pinst(kobj); __padata_free(pinst); } struct padata_sysfs_entry { struct attribute attr; ssize_t (*show)(struct padata_instance *, struct attribute *, char *); ssize_t (*store)(struct padata_instance *, struct attribute *, const char *, size_t); }; static ssize_t show_cpumask(struct padata_instance *pinst, struct attribute *attr, char *buf) { struct cpumask *cpumask; ssize_t len; mutex_lock(&pinst->lock); if (!strcmp(attr->name, "serial_cpumask")) cpumask = pinst->cpumask.cbcpu; else cpumask = pinst->cpumask.pcpu; len = bitmap_scnprintf(buf, PAGE_SIZE, cpumask_bits(cpumask), nr_cpu_ids); if (PAGE_SIZE - len < 2) len = -EINVAL; else len += sprintf(buf + len, " "); mutex_unlock(&pinst->lock); return len; } static ssize_t store_cpumask(struct padata_instance *pinst, struct attribute *attr, const char *buf, size_t count) { cpumask_var_t new_cpumask; ssize_t ret; int mask_type; if (!alloc_cpumask_var(&new_cpumask, GFP_KERNEL)) return -ENOMEM; ret = bitmap_parse(buf, count, cpumask_bits(new_cpumask), nr_cpumask_bits); if (ret < 0) goto out; mask_type = !strcmp(attr->name, "serial_cpumask") ? PADATA_CPU_SERIAL : PADATA_CPU_PARALLEL; ret = padata_set_cpumask(pinst, mask_type, new_cpumask); if (!ret) ret = count; out: free_cpumask_var(new_cpumask); return ret; } #define PADATA_ATTR_RW(_name, _show_name, _store_name) \ static struct padata_sysfs_entry _name##_attr = \ __ATTR(_name, 0644, _show_name, _store_name) #define PADATA_ATTR_RO(_name, _show_name) \ static struct padata_sysfs_entry _name##_attr = \ __ATTR(_name, 0400, _show_name, NULL) PADATA_ATTR_RW(serial_cpumask, show_cpumask, store_cpumask); PADATA_ATTR_RW(parallel_cpumask, show_cpumask, store_cpumask); /* * Padata sysfs provides the following objects: * serial_cpumask [RW] - cpumask for serial workers * parallel_cpumask [RW] - cpumask for parallel workers */ static struct attribute *padata_default_attrs[] = { &serial_cpumask_attr.attr, ¶llel_cpumask_attr.attr, NULL, }; static ssize_t padata_sysfs_show(struct kobject *kobj, struct attribute *attr, char *buf) { struct padata_instance *pinst; struct padata_sysfs_entry *pentry; ssize_t ret = -EIO; pinst = kobj2pinst(kobj); pentry = attr2pentry(attr); if (pentry->show) ret = pentry->show(pinst, attr, buf); return ret; } static ssize_t padata_sysfs_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count) { struct padata_instance *pinst; struct padata_sysfs_entry *pentry; ssize_t ret = -EIO; pinst = kobj2pinst(kobj); pentry = attr2pentry(attr); if (pentry->show) ret = pentry->store(pinst, attr, buf, count); return ret; } static const struct sysfs_ops padata_sysfs_ops = { .show = padata_sysfs_show, .store = padata_sysfs_store, }; static struct kobj_type padata_attr_type = { .sysfs_ops = &padata_sysfs_ops, .default_attrs = padata_default_attrs, .release = padata_sysfs_release, }; |
0198ffd13
|
987 |
/** |
e6cc11707
|
988 989 990 |
* padata_alloc_possible - Allocate and initialize padata instance. * Use the cpu_possible_mask for serial and * parallel workers. |
16295bec6
|
991 |
* |
16295bec6
|
992 993 |
* @wq: workqueue to use for the allocated padata instance */ |
e6cc11707
|
994 |
struct padata_instance *padata_alloc_possible(struct workqueue_struct *wq) |
e15bacbeb
|
995 |
{ |
e6cc11707
|
996 |
return padata_alloc(wq, cpu_possible_mask, cpu_possible_mask); |
e15bacbeb
|
997 |
} |
e6cc11707
|
998 |
EXPORT_SYMBOL(padata_alloc_possible); |
e15bacbeb
|
999 1000 |
/** |
e6cc11707
|
1001 1002 |
* padata_alloc - allocate and initialize a padata instance and specify * cpumasks for serial and parallel workers. |
16295bec6
|
1003 |
* |
16295bec6
|
1004 |
* @wq: workqueue to use for the allocated padata instance |
e15bacbeb
|
1005 1006 |
* @pcpumask: cpumask that will be used for padata parallelization * @cbcpumask: cpumask that will be used for padata serialization |
16295bec6
|
1007 |
*/ |
e6cc11707
|
1008 1009 1010 |
struct padata_instance *padata_alloc(struct workqueue_struct *wq, const struct cpumask *pcpumask, const struct cpumask *cbcpumask) |
16295bec6
|
1011 |
{ |
16295bec6
|
1012 |
struct padata_instance *pinst; |
33e544506
|
1013 |
struct parallel_data *pd = NULL; |
16295bec6
|
1014 1015 1016 1017 |
pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL); if (!pinst) goto err; |
6751fb3c0
|
1018 |
get_online_cpus(); |
e15bacbeb
|
1019 |
if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL)) |
16295bec6
|
1020 |
goto err_free_inst; |
e15bacbeb
|
1021 1022 |
if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) { free_cpumask_var(pinst->cpumask.pcpu); |
16295bec6
|
1023 |
goto err_free_inst; |
33e544506
|
1024 |
} |
e15bacbeb
|
1025 1026 1027 |
if (!padata_validate_cpumask(pinst, pcpumask) || !padata_validate_cpumask(pinst, cbcpumask)) goto err_free_masks; |
16295bec6
|
1028 |
|
e15bacbeb
|
1029 1030 1031 |
pd = padata_alloc_pd(pinst, pcpumask, cbcpumask); if (!pd) goto err_free_masks; |
747813878
|
1032 |
|
16295bec6
|
1033 1034 1035 |
rcu_assign_pointer(pinst->pd, pd); pinst->wq = wq; |
e15bacbeb
|
1036 1037 |
cpumask_copy(pinst->cpumask.pcpu, pcpumask); cpumask_copy(pinst->cpumask.cbcpu, cbcpumask); |
16295bec6
|
1038 1039 |
pinst->flags = 0; |
e2cb2f1c2
|
1040 |
#ifdef CONFIG_HOTPLUG_CPU |
16295bec6
|
1041 1042 |
pinst->cpu_notifier.notifier_call = padata_cpu_callback; pinst->cpu_notifier.priority = 0; |
e2cb2f1c2
|
1043 1044 |
register_hotcpu_notifier(&pinst->cpu_notifier); #endif |
16295bec6
|
1045 |
|
6751fb3c0
|
1046 |
put_online_cpus(); |
e15bacbeb
|
1047 |
BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier); |
5e017dc3f
|
1048 |
kobject_init(&pinst->kobj, &padata_attr_type); |
16295bec6
|
1049 1050 1051 |
mutex_init(&pinst->lock); return pinst; |
e15bacbeb
|
1052 1053 1054 |
err_free_masks: free_cpumask_var(pinst->cpumask.pcpu); free_cpumask_var(pinst->cpumask.cbcpu); |
16295bec6
|
1055 1056 |
err_free_inst: kfree(pinst); |
6751fb3c0
|
1057 |
put_online_cpus(); |
16295bec6
|
1058 1059 1060 1061 |
err: return NULL; } EXPORT_SYMBOL(padata_alloc); |
0198ffd13
|
1062 |
/** |
16295bec6
|
1063 1064 |
* padata_free - free a padata instance * |
0198ffd13
|
1065 |
* @padata_inst: padata instance to free |
16295bec6
|
1066 1067 1068 |
*/ void padata_free(struct padata_instance *pinst) { |
5e017dc3f
|
1069 |
kobject_put(&pinst->kobj); |
16295bec6
|
1070 1071 |
} EXPORT_SYMBOL(padata_free); |