/*
* linux/net/sunrpc/sched.c
*
* Scheduling for synchronous and asynchronous RPC requests.
*
* Copyright (C) 1996 Olaf Kirch, <okir@monad.swb.de>
*
* TCP NFS related read + write fixes
* (C) 1999 Dave Airlie, University of Limerick, Ireland <airlied@linux.ie>
*/
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/mempool.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/freezer.h>
#include <linux/sunrpc/clnt.h>
#include "sunrpc.h"
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
#define RPCDBG_FACILITY RPCDBG_SCHED
#endif
#define CREATE_TRACE_POINTS
#include <trace/events/sunrpc.h>
/*
* RPC slabs and memory pools
*/
#define RPC_BUFFER_MAXSIZE (2048)
#define RPC_BUFFER_POOLSIZE (8)
#define RPC_TASK_POOLSIZE (8)
static struct kmem_cache *rpc_task_slabp __read_mostly;
static struct kmem_cache *rpc_buffer_slabp __read_mostly;
static mempool_t *rpc_task_mempool __read_mostly;
static mempool_t *rpc_buffer_mempool __read_mostly;
static void rpc_async_schedule(struct work_struct *);
static void rpc_release_task(struct rpc_task *task);
static void __rpc_queue_timer_fn(struct timer_list *t);
/*
* RPC tasks sit here while waiting for conditions to improve.
*/
static struct rpc_wait_queue delay_queue;
/*
* rpciod-related stuff
*/
struct workqueue_struct *rpciod_workqueue __read_mostly;
struct workqueue_struct *xprtiod_workqueue __read_mostly;
/*
* Disable the timer for a given RPC task. Should be called with
* queue->lock and bh_disabled in order to avoid races within
* rpc_run_timer().
*/
static void
__rpc_disable_timer(struct rpc_wait_queue *queue, struct rpc_task *task)
{
if (task->tk_timeout == 0)
return;
dprintk("RPC: %5u disabling timer\n", task->tk_pid);
task->tk_timeout = 0;
list_del(&task->u.tk_wait.timer_list);
if (list_empty(&queue->timer_list.list))
del_timer(&queue->timer_list.timer);
}
static void
rpc_set_queue_timer(struct rpc_wait_queue *queue, unsigned long expires)
{
queue->timer_list.expires = expires;
mod_timer(&queue->timer_list.timer, expires);
}
/*
* Set up a timer for the current task.
*/
static void
__rpc_add_timer(struct rpc_wait_queue *queue, struct rpc_task *task)
{
if (!task->tk_timeout)
return;
dprintk("RPC: %5u setting alarm for %u ms\n",
task->tk_pid, jiffies_to_msecs(task->tk_timeout));
task->u.tk_wait.expires = jiffies + task->tk_timeout;
if (list_empty(&queue->timer_list.list) || time_before(task->u.tk_wait.expires, queue->timer_list.expires))
rpc_set_queue_timer(queue, task->u.tk_wait.expires);
list_add(&task->u.tk_wait.timer_list, &queue->timer_list.list);
}
static void rpc_set_waitqueue_priority(struct rpc_wait_queue *queue, int priority)
{
if (queue->priority != priority) {
queue->