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kernel/padata.c
25.4 KB
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/* * padata.c - generic interface to process data streams in parallel * |
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* See Documentation/padata.txt for an api documentation. * |
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* 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. */ |
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#include <linux/export.h> |
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#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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#include <linux/module.h> |
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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; } |
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static int padata_cpu_hash(struct parallel_data *pd) |
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{ |
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unsigned int seq_nr; |
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int cpu_index; |
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/* * Hash the sequence numbers to the cpus by taking * seq_nr mod. number of cpus in use. */ |
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seq_nr = atomic_inc_return(&pd->seq_nr); cpu_index = 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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LIST_HEAD(local_list); local_bh_disable(); |
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pqueue = container_of(parallel_work, struct padata_parallel_queue, work); |
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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(); |
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pd = rcu_dereference_bh(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; |
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target_cpu = padata_cpu_hash(pd); |
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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. * |
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* -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; |
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unsigned int next_nr, next_index; |
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struct padata_parallel_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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reorder = &next_queue->reorder; |
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spin_lock(&reorder->lock); |
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if (!list_empty(&reorder->list)) { padata = list_entry(reorder->list.next, struct padata_priv, list); |
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list_del_init(&padata->list); atomic_dec(&pd->reorder_objects); |
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pd->processed++; |
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spin_unlock(&reorder->lock); |
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goto out; } |
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spin_unlock(&reorder->lock); |
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if (__this_cpu_read(pd->pqueue->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) { |
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int cb_cpu; |
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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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/* |
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* If 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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*/ |
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if (PTR_ERR(padata) == -EINPROGRESS) |
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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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cb_cpu = padata->cb_cpu; squeue = per_cpu_ptr(pd->squeue, 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(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_online_mask); |
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if (!alloc_cpumask_var(&pd->cpumask.cbcpu, GFP_KERNEL)) { |
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free_cpumask_var(pd->cpumask.pcpu); |
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return -ENOMEM; } |
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cpumask_and(pd->cpumask.cbcpu, cbcpumask, cpu_online_mask); |
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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) { |
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int cpu_index, cpu; |
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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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} |
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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); |
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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) { |
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525 |
if (!cpumask_intersects(cpumask, cpu_online_mask)) { |
33e544506
|
526 527 528 529 530 531 532 |
pinst->flags |= PADATA_INVALID; return false; } pinst->flags &= ~PADATA_INVALID; return true; } |
65ff577e6
|
533 534 535 536 537 |
static int __padata_set_cpumasks(struct padata_instance *pinst, cpumask_var_t pcpumask, cpumask_var_t cbcpumask) { int valid; |
16295bec6
|
538 |
struct parallel_data *pd; |
65ff577e6
|
539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 |
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; } /** |
e15bacbeb
|
567 568 |
* padata_set_cpumask: Sets specified by @cpumask_type cpumask to the value * equivalent to @cpumask. |
16295bec6
|
569 570 |
* * @pinst: padata instance |
e15bacbeb
|
571 572 |
* @cpumask_type: PADATA_CPU_SERIAL or PADATA_CPU_PARALLEL corresponding * to parallel and serial cpumasks respectively. |
16295bec6
|
573 574 |
* @cpumask: the cpumask to use */ |
e15bacbeb
|
575 576 577 578 |
int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type, cpumask_var_t cpumask) { struct cpumask *serial_mask, *parallel_mask; |
65ff577e6
|
579 580 581 |
int err = -EINVAL; mutex_lock(&pinst->lock); |
6751fb3c0
|
582 |
get_online_cpus(); |
e15bacbeb
|
583 584 585 586 587 588 589 590 591 592 |
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
|
593 |
goto out; |
16295bec6
|
594 |
} |
65ff577e6
|
595 |
err = __padata_set_cpumasks(pinst, parallel_mask, serial_mask); |
16295bec6
|
596 597 |
out: |
6751fb3c0
|
598 |
put_online_cpus(); |
16295bec6
|
599 600 601 602 603 |
mutex_unlock(&pinst->lock); return err; } EXPORT_SYMBOL(padata_set_cpumask); |
19d795b67
|
604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 |
/** * padata_start - start the parallel processing * * @pinst: padata instance to start */ int padata_start(struct padata_instance *pinst) { int err = 0; mutex_lock(&pinst->lock); if (pinst->flags & PADATA_INVALID) err = -EINVAL; __padata_start(pinst); mutex_unlock(&pinst->lock); return err; } EXPORT_SYMBOL(padata_start); /** * padata_stop - stop the parallel processing * * @pinst: padata instance to stop */ void padata_stop(struct padata_instance *pinst) { mutex_lock(&pinst->lock); __padata_stop(pinst); mutex_unlock(&pinst->lock); } EXPORT_SYMBOL(padata_stop); #ifdef CONFIG_HOTPLUG_CPU |
16295bec6
|
640 641 642 |
static int __padata_add_cpu(struct padata_instance *pinst, int cpu) { struct parallel_data *pd; |
13614e0fb
|
643 |
if (cpumask_test_cpu(cpu, cpu_online_mask)) { |
e15bacbeb
|
644 645 |
pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu, pinst->cpumask.cbcpu); |
16295bec6
|
646 647 648 649 |
if (!pd) return -ENOMEM; padata_replace(pinst, pd); |
33e544506
|
650 |
|
e15bacbeb
|
651 652 |
if (padata_validate_cpumask(pinst, pinst->cpumask.pcpu) && padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) |
33e544506
|
653 |
__padata_start(pinst); |
16295bec6
|
654 655 656 657 |
} return 0; } |
16295bec6
|
658 659 |
static int __padata_remove_cpu(struct padata_instance *pinst, int cpu) { |
33e544506
|
660 |
struct parallel_data *pd = NULL; |
16295bec6
|
661 662 |
if (cpumask_test_cpu(cpu, cpu_online_mask)) { |
33e544506
|
663 |
|
e15bacbeb
|
664 |
if (!padata_validate_cpumask(pinst, pinst->cpumask.pcpu) || |
b89661dff
|
665 |
!padata_validate_cpumask(pinst, pinst->cpumask.cbcpu)) |
33e544506
|
666 |
__padata_stop(pinst); |
33e544506
|
667 |
|
e15bacbeb
|
668 669 |
pd = padata_alloc_pd(pinst, pinst->cpumask.pcpu, pinst->cpumask.cbcpu); |
16295bec6
|
670 671 672 673 |
if (!pd) return -ENOMEM; padata_replace(pinst, pd); |
961209052
|
674 675 676 |
cpumask_clear_cpu(cpu, pd->cpumask.cbcpu); cpumask_clear_cpu(cpu, pd->cpumask.pcpu); |
16295bec6
|
677 678 679 680 |
} return 0; } |
e15bacbeb
|
681 |
/** |
25985edce
|
682 |
* padata_remove_cpu - remove a cpu from the one or both(serial and parallel) |
e15bacbeb
|
683 |
* padata cpumasks. |
16295bec6
|
684 685 686 |
* * @pinst: padata instance * @cpu: cpu to remove |
e15bacbeb
|
687 688 689 690 |
* @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
|
691 |
*/ |
e15bacbeb
|
692 |
int padata_remove_cpu(struct padata_instance *pinst, int cpu, int mask) |
16295bec6
|
693 694 |
{ int err; |
e15bacbeb
|
695 696 |
if (!(mask & (PADATA_CPU_SERIAL | PADATA_CPU_PARALLEL))) return -EINVAL; |
16295bec6
|
697 |
mutex_lock(&pinst->lock); |
6751fb3c0
|
698 |
get_online_cpus(); |
e15bacbeb
|
699 700 701 702 |
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
|
703 |
err = __padata_remove_cpu(pinst, cpu); |
6751fb3c0
|
704 |
put_online_cpus(); |
16295bec6
|
705 706 707 708 709 710 |
mutex_unlock(&pinst->lock); return err; } EXPORT_SYMBOL(padata_remove_cpu); |
e15bacbeb
|
711 712 713 714 715 |
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); } |
30e92153b
|
716 |
static int padata_cpu_online(unsigned int cpu, struct hlist_node *node) |
16295bec6
|
717 |
{ |
16295bec6
|
718 |
struct padata_instance *pinst; |
30e92153b
|
719 |
int ret; |
16295bec6
|
720 |
|
30e92153b
|
721 722 723 |
pinst = hlist_entry_safe(node, struct padata_instance, node); if (!pinst_has_cpu(pinst, cpu)) return 0; |
16295bec6
|
724 |
|
30e92153b
|
725 726 727 728 729 |
mutex_lock(&pinst->lock); ret = __padata_add_cpu(pinst, cpu); mutex_unlock(&pinst->lock); return ret; } |
16295bec6
|
730 |
|
30e92153b
|
731 732 733 734 735 736 737 738 |
static int padata_cpu_prep_down(unsigned int cpu, struct hlist_node *node) { struct padata_instance *pinst; int ret; pinst = hlist_entry_safe(node, struct padata_instance, node); if (!pinst_has_cpu(pinst, cpu)) return 0; |
16295bec6
|
739 |
|
30e92153b
|
740 741 742 743 |
mutex_lock(&pinst->lock); ret = __padata_remove_cpu(pinst, cpu); mutex_unlock(&pinst->lock); return ret; |
16295bec6
|
744 |
} |
30e92153b
|
745 746 |
static enum cpuhp_state hp_online; |
e2cb2f1c2
|
747 |
#endif |
16295bec6
|
748 |
|
5e017dc3f
|
749 750 751 |
static void __padata_free(struct padata_instance *pinst) { #ifdef CONFIG_HOTPLUG_CPU |
30e92153b
|
752 |
cpuhp_state_remove_instance_nocalls(hp_online, &pinst->node); |
5e017dc3f
|
753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 |
#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; |
4497da6f9
|
791 792 793 |
len = snprintf(buf, PAGE_SIZE, "%*pb ", nr_cpu_ids, cpumask_bits(cpumask)); |
5e017dc3f
|
794 |
mutex_unlock(&pinst->lock); |
4497da6f9
|
795 |
return len < PAGE_SIZE ? len : -EINVAL; |
5e017dc3f
|
796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 |
} 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
|
886 |
/** |
e6cc11707
|
887 888 |
* padata_alloc - allocate and initialize a padata instance and specify * cpumasks for serial and parallel workers. |
16295bec6
|
889 |
* |
16295bec6
|
890 |
* @wq: workqueue to use for the allocated padata instance |
e15bacbeb
|
891 892 |
* @pcpumask: cpumask that will be used for padata parallelization * @cbcpumask: cpumask that will be used for padata serialization |
c5a81c8ff
|
893 894 |
* * Must be called from a cpus_read_lock() protected region |
16295bec6
|
895 |
*/ |
9596695ee
|
896 897 898 |
static struct padata_instance *padata_alloc(struct workqueue_struct *wq, const struct cpumask *pcpumask, const struct cpumask *cbcpumask) |
16295bec6
|
899 |
{ |
16295bec6
|
900 |
struct padata_instance *pinst; |
33e544506
|
901 |
struct parallel_data *pd = NULL; |
16295bec6
|
902 903 904 905 |
pinst = kzalloc(sizeof(struct padata_instance), GFP_KERNEL); if (!pinst) goto err; |
e15bacbeb
|
906 |
if (!alloc_cpumask_var(&pinst->cpumask.pcpu, GFP_KERNEL)) |
16295bec6
|
907 |
goto err_free_inst; |
e15bacbeb
|
908 909 |
if (!alloc_cpumask_var(&pinst->cpumask.cbcpu, GFP_KERNEL)) { free_cpumask_var(pinst->cpumask.pcpu); |
16295bec6
|
910 |
goto err_free_inst; |
33e544506
|
911 |
} |
e15bacbeb
|
912 913 914 |
if (!padata_validate_cpumask(pinst, pcpumask) || !padata_validate_cpumask(pinst, cbcpumask)) goto err_free_masks; |
16295bec6
|
915 |
|
e15bacbeb
|
916 917 918 |
pd = padata_alloc_pd(pinst, pcpumask, cbcpumask); if (!pd) goto err_free_masks; |
747813878
|
919 |
|
16295bec6
|
920 921 922 |
rcu_assign_pointer(pinst->pd, pd); pinst->wq = wq; |
e15bacbeb
|
923 924 |
cpumask_copy(pinst->cpumask.pcpu, pcpumask); cpumask_copy(pinst->cpumask.cbcpu, cbcpumask); |
16295bec6
|
925 926 |
pinst->flags = 0; |
e15bacbeb
|
927 |
BLOCKING_INIT_NOTIFIER_HEAD(&pinst->cpumask_change_notifier); |
5e017dc3f
|
928 |
kobject_init(&pinst->kobj, &padata_attr_type); |
16295bec6
|
929 |
mutex_init(&pinst->lock); |
b8b4a4166
|
930 |
#ifdef CONFIG_HOTPLUG_CPU |
c5a81c8ff
|
931 |
cpuhp_state_add_instance_nocalls_cpuslocked(hp_online, &pinst->node); |
b8b4a4166
|
932 |
#endif |
16295bec6
|
933 |
return pinst; |
e15bacbeb
|
934 935 936 |
err_free_masks: free_cpumask_var(pinst->cpumask.pcpu); free_cpumask_var(pinst->cpumask.cbcpu); |
16295bec6
|
937 938 939 940 941 |
err_free_inst: kfree(pinst); err: return NULL; } |
16295bec6
|
942 |
|
0198ffd13
|
943 |
/** |
9596695ee
|
944 945 946 947 948 |
* padata_alloc_possible - Allocate and initialize padata instance. * Use the cpu_possible_mask for serial and * parallel workers. * * @wq: workqueue to use for the allocated padata instance |
c5a81c8ff
|
949 950 |
* * Must be called from a cpus_read_lock() protected region |
9596695ee
|
951 952 953 |
*/ struct padata_instance *padata_alloc_possible(struct workqueue_struct *wq) { |
c5a81c8ff
|
954 |
lockdep_assert_cpus_held(); |
9596695ee
|
955 956 957 958 959 |
return padata_alloc(wq, cpu_possible_mask, cpu_possible_mask); } EXPORT_SYMBOL(padata_alloc_possible); /** |
16295bec6
|
960 961 |
* padata_free - free a padata instance * |
0198ffd13
|
962 |
* @padata_inst: padata instance to free |
16295bec6
|
963 964 965 |
*/ void padata_free(struct padata_instance *pinst) { |
5e017dc3f
|
966 |
kobject_put(&pinst->kobj); |
16295bec6
|
967 968 |
} EXPORT_SYMBOL(padata_free); |
30e92153b
|
969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 |
#ifdef CONFIG_HOTPLUG_CPU static __init int padata_driver_init(void) { int ret; ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "padata:online", padata_cpu_online, padata_cpu_prep_down); if (ret < 0) return ret; hp_online = ret; return 0; } module_init(padata_driver_init); static __exit void padata_driver_exit(void) { cpuhp_remove_multi_state(hp_online); } module_exit(padata_driver_exit); #endif |