X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=net%2Fsunrpc%2Fsched.c;h=b5723c262a3efd4703ea95f7936994845626f956;hb=a4fb2122f1fc4a22bd6a5b8a195b952c2d31c54d;hp=944d75396fb3a39448b20c4036932917c631dd46;hpb=0b662c64840fb281e5948ab6f9d60f84817277d0;p=linux-2.6 diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c index 944d75396f..b5723c262a 100644 --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -25,7 +25,6 @@ #ifdef RPC_DEBUG #define RPCDBG_FACILITY RPCDBG_SCHED #define RPC_TASK_MAGIC_ID 0xf00baa -static int rpc_task_id; #endif /* @@ -40,7 +39,6 @@ static mempool_t *rpc_task_mempool __read_mostly; static mempool_t *rpc_buffer_mempool __read_mostly; static void __rpc_default_timer(struct rpc_task *task); -static void rpciod_killall(void); static void rpc_async_schedule(struct work_struct *); static void rpc_release_task(struct rpc_task *task); @@ -49,23 +47,13 @@ static void rpc_release_task(struct rpc_task *task); */ static RPC_WAITQ(delay_queue, "delayq"); -/* - * All RPC tasks are linked into this list - */ -static LIST_HEAD(all_tasks); - /* * rpciod-related stuff */ static DEFINE_MUTEX(rpciod_mutex); -static unsigned int rpciod_users; +static atomic_t rpciod_users = ATOMIC_INIT(0); struct workqueue_struct *rpciod_workqueue; -/* - * Spinlock for other critical sections of code. - */ -static DEFINE_SPINLOCK(rpc_sched_lock); - /* * Disable the timer for a given RPC task. Should be called with * queue->lock and bh_disabled in order to avoid races within @@ -267,18 +255,33 @@ static int rpc_wait_bit_interruptible(void *word) return 0; } +#ifdef RPC_DEBUG +static void rpc_task_set_debuginfo(struct rpc_task *task) +{ + static atomic_t rpc_pid; + + task->tk_magic = RPC_TASK_MAGIC_ID; + task->tk_pid = atomic_inc_return(&rpc_pid); +} +#else +static inline void rpc_task_set_debuginfo(struct rpc_task *task) +{ +} +#endif + static void rpc_set_active(struct rpc_task *task) { + struct rpc_clnt *clnt; if (test_and_set_bit(RPC_TASK_ACTIVE, &task->tk_runstate) != 0) return; - spin_lock(&rpc_sched_lock); -#ifdef RPC_DEBUG - task->tk_magic = RPC_TASK_MAGIC_ID; - task->tk_pid = rpc_task_id++; -#endif + rpc_task_set_debuginfo(task); /* Add to global list of all tasks */ - list_add_tail(&task->tk_task, &all_tasks); - spin_unlock(&rpc_sched_lock); + clnt = task->tk_client; + if (clnt != NULL) { + spin_lock(&clnt->cl_lock); + list_add_tail(&task->tk_task, &clnt->cl_tasks); + spin_unlock(&clnt->cl_lock); + } } /* @@ -818,6 +821,7 @@ void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, int flags, cons if (tk_ops->rpc_call_prepare != NULL) task->tk_action = rpc_prepare_task; task->tk_calldata = calldata; + INIT_LIST_HEAD(&task->tk_task); /* Initialize retry counters */ task->tk_garb_retry = 2; @@ -830,7 +834,7 @@ void rpc_init_task(struct rpc_task *task, struct rpc_clnt *clnt, int flags, cons task->tk_workqueue = rpciod_workqueue; if (clnt) { - atomic_inc(&clnt->cl_users); + kref_get(&clnt->cl_kref); if (clnt->cl_softrtry) task->tk_flags |= RPC_TASK_SOFT; if (!clnt->cl_intr) @@ -860,9 +864,7 @@ static void rpc_free_task(struct rcu_head *rcu) } /* - * Create a new task for the specified client. We have to - * clean up after an allocation failure, as the client may - * have specified "oneshot". + * Create a new task for the specified client. */ struct rpc_task *rpc_new_task(struct rpc_clnt *clnt, int flags, const struct rpc_call_ops *tk_ops, void *calldata) { @@ -870,7 +872,7 @@ struct rpc_task *rpc_new_task(struct rpc_clnt *clnt, int flags, const struct rpc task = rpc_alloc_task(); if (!task) - goto cleanup; + goto out; rpc_init_task(task, clnt, flags, tk_ops, calldata); @@ -878,16 +880,6 @@ struct rpc_task *rpc_new_task(struct rpc_clnt *clnt, int flags, const struct rpc task->tk_flags |= RPC_TASK_DYNAMIC; out: return task; - -cleanup: - /* Check whether to release the client */ - if (clnt) { - printk("rpc_new_task: failed, users=%d, oneshot=%d\n", - atomic_read(&clnt->cl_users), clnt->cl_oneshot); - atomic_inc(&clnt->cl_users); /* pretend we were used ... */ - rpc_release_client(clnt); - } - goto out; } @@ -920,11 +912,13 @@ static void rpc_release_task(struct rpc_task *task) #endif dprintk("RPC: %5u release task\n", task->tk_pid); - /* Remove from global task list */ - spin_lock(&rpc_sched_lock); - list_del(&task->tk_task); - spin_unlock(&rpc_sched_lock); - + if (!list_empty(&task->tk_task)) { + struct rpc_clnt *clnt = task->tk_client; + /* Remove from client task list */ + spin_lock(&clnt->cl_lock); + list_del(&task->tk_task); + spin_unlock(&clnt->cl_lock); + } BUG_ON (RPC_IS_QUEUED(task)); /* Synchronously delete any running timer */ @@ -939,29 +933,6 @@ static void rpc_release_task(struct rpc_task *task) rpc_put_task(task); } -/** - * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it - * @clnt: pointer to RPC client - * @flags: RPC flags - * @ops: RPC call ops - * @data: user call data - */ -struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags, - const struct rpc_call_ops *ops, - void *data) -{ - struct rpc_task *task; - task = rpc_new_task(clnt, flags, ops, data); - if (task == NULL) { - rpc_release_calldata(ops, data); - return ERR_PTR(-ENOMEM); - } - atomic_inc(&task->tk_count); - rpc_execute(task); - return task; -} -EXPORT_SYMBOL(rpc_run_task); - /* * Kill all tasks for the given client. * XXX: kill their descendants as well? @@ -969,44 +940,25 @@ EXPORT_SYMBOL(rpc_run_task); void rpc_killall_tasks(struct rpc_clnt *clnt) { struct rpc_task *rovr; - struct list_head *le; - dprintk("RPC: killing all tasks for client %p\n", clnt); + if (list_empty(&clnt->cl_tasks)) + return; + dprintk("RPC: killing all tasks for client %p\n", clnt); /* * Spin lock all_tasks to prevent changes... */ - spin_lock(&rpc_sched_lock); - alltask_for_each(rovr, le, &all_tasks) { + spin_lock(&clnt->cl_lock); + list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) { if (! RPC_IS_ACTIVATED(rovr)) continue; - if (!clnt || rovr->tk_client == clnt) { + if (!(rovr->tk_flags & RPC_TASK_KILLED)) { rovr->tk_flags |= RPC_TASK_KILLED; rpc_exit(rovr, -EIO); rpc_wake_up_task(rovr); } } - spin_unlock(&rpc_sched_lock); -} - -static void rpciod_killall(void) -{ - unsigned long flags; - - while (!list_empty(&all_tasks)) { - clear_thread_flag(TIF_SIGPENDING); - rpc_killall_tasks(NULL); - flush_workqueue(rpciod_workqueue); - if (!list_empty(&all_tasks)) { - dprintk("RPC: rpciod_killall: waiting for tasks " - "to exit\n"); - yield(); - } - } - - spin_lock_irqsave(¤t->sighand->siglock, flags); - recalc_sigpending(); - spin_unlock_irqrestore(¤t->sighand->siglock, flags); + spin_unlock(&clnt->cl_lock); } /* @@ -1018,28 +970,27 @@ rpciod_up(void) struct workqueue_struct *wq; int error = 0; + if (atomic_inc_not_zero(&rpciod_users)) + return 0; + mutex_lock(&rpciod_mutex); - dprintk("RPC: rpciod_up: users %u\n", rpciod_users); - rpciod_users++; - if (rpciod_workqueue) - goto out; - /* - * If there's no pid, we should be the first user. - */ - if (rpciod_users > 1) - printk(KERN_WARNING "rpciod_up: no workqueue, %u users??\n", rpciod_users); + + /* Guard against races with rpciod_down() */ + if (rpciod_workqueue != NULL) + goto out_ok; /* * Create the rpciod thread and wait for it to start. */ + dprintk("RPC: creating workqueue rpciod\n"); error = -ENOMEM; wq = create_workqueue("rpciod"); - if (wq == NULL) { - printk(KERN_WARNING "rpciod_up: create workqueue failed, error=%d\n", error); - rpciod_users--; + if (wq == NULL) goto out; - } + rpciod_workqueue = wq; error = 0; +out_ok: + atomic_inc(&rpciod_users); out: mutex_unlock(&rpciod_mutex); return error; @@ -1048,59 +999,19 @@ out: void rpciod_down(void) { + if (!atomic_dec_and_test(&rpciod_users)) + return; + mutex_lock(&rpciod_mutex); - dprintk("RPC: rpciod_down sema %u\n", rpciod_users); - if (rpciod_users) { - if (--rpciod_users) - goto out; - } else - printk(KERN_WARNING "rpciod_down: no users??\n"); + dprintk("RPC: destroying workqueue rpciod\n"); - if (!rpciod_workqueue) { - dprintk("RPC: rpciod_down: Nothing to do!\n"); - goto out; + if (atomic_read(&rpciod_users) == 0 && rpciod_workqueue != NULL) { + destroy_workqueue(rpciod_workqueue); + rpciod_workqueue = NULL; } - rpciod_killall(); - - destroy_workqueue(rpciod_workqueue); - rpciod_workqueue = NULL; - out: mutex_unlock(&rpciod_mutex); } -#ifdef RPC_DEBUG -void rpc_show_tasks(void) -{ - struct list_head *le; - struct rpc_task *t; - - spin_lock(&rpc_sched_lock); - if (list_empty(&all_tasks)) { - spin_unlock(&rpc_sched_lock); - return; - } - printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout " - "-rpcwait -action- ---ops--\n"); - alltask_for_each(t, le, &all_tasks) { - const char *rpc_waitq = "none"; - - if (RPC_IS_QUEUED(t)) - rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq); - - printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n", - t->tk_pid, - (t->tk_msg.rpc_proc ? t->tk_msg.rpc_proc->p_proc : -1), - t->tk_flags, t->tk_status, - t->tk_client, - (t->tk_client ? t->tk_client->cl_prog : 0), - t->tk_rqstp, t->tk_timeout, - rpc_waitq, - t->tk_action, t->tk_ops); - } - spin_unlock(&rpc_sched_lock); -} -#endif - void rpc_destroy_mempool(void) { @@ -1120,13 +1031,13 @@ rpc_init_mempool(void) rpc_task_slabp = kmem_cache_create("rpc_tasks", sizeof(struct rpc_task), 0, SLAB_HWCACHE_ALIGN, - NULL, NULL); + NULL); if (!rpc_task_slabp) goto err_nomem; rpc_buffer_slabp = kmem_cache_create("rpc_buffers", RPC_BUFFER_MAXSIZE, 0, SLAB_HWCACHE_ALIGN, - NULL, NULL); + NULL); if (!rpc_buffer_slabp) goto err_nomem; rpc_task_mempool = mempool_create_slab_pool(RPC_TASK_POOLSIZE,