From ee74baa7d83e9e0c2fdaff8122ee9cefd06cddc5 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 1 Jan 2007 20:51:53 -0800 Subject: [PATCH] [PKTGEN]: Convert to kthread API. Based upon a suggestion from Christoph Hellwig. This fixes various races in module load/unload handling too. Signed-off-by: David S. Miller --- net/core/pktgen.c | 156 ++++++++++++++-------------------------------- 1 file changed, 48 insertions(+), 108 deletions(-) diff --git a/net/core/pktgen.c b/net/core/pktgen.c index 1897a3a385d8..04d4b93c68eb 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -148,6 +148,7 @@ #include #include #include +#include #include #include #include @@ -360,8 +361,7 @@ struct pktgen_thread { spinlock_t if_lock; struct list_head if_list; /* All device here */ struct list_head th_list; - int removed; - char name[32]; + struct task_struct *tsk; char result[512]; u32 max_before_softirq; /* We'll call do_softirq to prevent starvation. */ @@ -1689,7 +1689,7 @@ static int pktgen_thread_show(struct seq_file *seq, void *v) BUG_ON(!t); seq_printf(seq, "Name: %s max_before_softirq: %d\n", - t->name, t->max_before_softirq); + t->tsk->comm, t->max_before_softirq); seq_printf(seq, "Running: "); @@ -3112,7 +3112,7 @@ static void pktgen_rem_thread(struct pktgen_thread *t) { /* Remove from the thread list */ - remove_proc_entry(t->name, pg_proc_dir); + remove_proc_entry(t->tsk->comm, pg_proc_dir); mutex_lock(&pktgen_thread_lock); @@ -3260,58 +3260,40 @@ out:; * Main loop of the thread goes here */ -static void pktgen_thread_worker(struct pktgen_thread *t) +static int pktgen_thread_worker(void *arg) { DEFINE_WAIT(wait); + struct pktgen_thread *t = arg; struct pktgen_dev *pkt_dev = NULL; int cpu = t->cpu; - sigset_t tmpsig; u32 max_before_softirq; u32 tx_since_softirq = 0; - daemonize("pktgen/%d", cpu); - - /* Block all signals except SIGKILL, SIGSTOP and SIGTERM */ - - spin_lock_irq(¤t->sighand->siglock); - tmpsig = current->blocked; - siginitsetinv(¤t->blocked, - sigmask(SIGKILL) | sigmask(SIGSTOP) | sigmask(SIGTERM)); - - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - - /* Migrate to the right CPU */ - set_cpus_allowed(current, cpumask_of_cpu(cpu)); - if (smp_processor_id() != cpu) - BUG(); + BUG_ON(smp_processor_id() != cpu); init_waitqueue_head(&t->queue); - t->control &= ~(T_TERMINATE); - t->control &= ~(T_RUN); - t->control &= ~(T_STOP); - t->control &= ~(T_REMDEVALL); - t->control &= ~(T_REMDEV); - t->pid = current->pid; PG_DEBUG(printk("pktgen: starting pktgen/%d: pid=%d\n", cpu, current->pid)); max_before_softirq = t->max_before_softirq; - __set_current_state(TASK_INTERRUPTIBLE); - mb(); + set_current_state(TASK_INTERRUPTIBLE); - while (1) { - - __set_current_state(TASK_RUNNING); + while (!kthread_should_stop()) { + pkt_dev = next_to_run(t); - /* - * Get next dev to xmit -- if any. - */ + if (!pkt_dev && + (t->control & (T_STOP | T_RUN | T_REMDEVALL | T_REMDEV)) + == 0) { + prepare_to_wait(&(t->queue), &wait, + TASK_INTERRUPTIBLE); + schedule_timeout(HZ / 10); + finish_wait(&(t->queue), &wait); + } - pkt_dev = next_to_run(t); + __set_current_state(TASK_RUNNING); if (pkt_dev) { @@ -3329,21 +3311,8 @@ static void pktgen_thread_worker(struct pktgen_thread *t) do_softirq(); tx_since_softirq = 0; } - } else { - prepare_to_wait(&(t->queue), &wait, TASK_INTERRUPTIBLE); - schedule_timeout(HZ / 10); - finish_wait(&(t->queue), &wait); } - /* - * Back from sleep, either due to the timeout or signal. - * We check if we have any "posted" work for us. - */ - - if (t->control & T_TERMINATE || signal_pending(current)) - /* we received a request to terminate ourself */ - break; - if (t->control & T_STOP) { pktgen_stop(t); t->control &= ~(T_STOP); @@ -3364,20 +3333,19 @@ static void pktgen_thread_worker(struct pktgen_thread *t) t->control &= ~(T_REMDEV); } - if (need_resched()) - schedule(); + set_current_state(TASK_INTERRUPTIBLE); } - PG_DEBUG(printk("pktgen: %s stopping all device\n", t->name)); + PG_DEBUG(printk("pktgen: %s stopping all device\n", t->tsk->comm)); pktgen_stop(t); - PG_DEBUG(printk("pktgen: %s removing all device\n", t->name)); + PG_DEBUG(printk("pktgen: %s removing all device\n", t->tsk->comm)); pktgen_rem_all_ifs(t); - PG_DEBUG(printk("pktgen: %s removing thread.\n", t->name)); + PG_DEBUG(printk("pktgen: %s removing thread.\n", t->tsk->comm)); pktgen_rem_thread(t); - t->removed = 1; + return 0; } static struct pktgen_dev *pktgen_find_dev(struct pktgen_thread *t, @@ -3495,37 +3463,11 @@ static int pktgen_add_device(struct pktgen_thread *t, const char *ifname) return add_dev_to_thread(t, pkt_dev); } -static struct pktgen_thread *__init pktgen_find_thread(const char *name) +static int __init pktgen_create_thread(int cpu) { struct pktgen_thread *t; - - mutex_lock(&pktgen_thread_lock); - - list_for_each_entry(t, &pktgen_threads, th_list) - if (strcmp(t->name, name) == 0) { - mutex_unlock(&pktgen_thread_lock); - return t; - } - - mutex_unlock(&pktgen_thread_lock); - return NULL; -} - -static int __init pktgen_create_thread(const char *name, int cpu) -{ - int err; - struct pktgen_thread *t = NULL; struct proc_dir_entry *pe; - - if (strlen(name) > 31) { - printk("pktgen: ERROR: Thread name cannot be more than 31 characters.\n"); - return -EINVAL; - } - - if (pktgen_find_thread(name)) { - printk("pktgen: ERROR: thread: %s already exists\n", name); - return -EINVAL; - } + struct task_struct *p; t = kzalloc(sizeof(struct pktgen_thread), GFP_KERNEL); if (!t) { @@ -3533,14 +3475,29 @@ static int __init pktgen_create_thread(const char *name, int cpu) return -ENOMEM; } - strcpy(t->name, name); spin_lock_init(&t->if_lock); t->cpu = cpu; - pe = create_proc_entry(t->name, 0600, pg_proc_dir); + INIT_LIST_HEAD(&t->if_list); + + list_add_tail(&t->th_list, &pktgen_threads); + + p = kthread_create(pktgen_thread_worker, t, "kpktgend_%d", cpu); + if (IS_ERR(p)) { + printk("pktgen: kernel_thread() failed for cpu %d\n", t->cpu); + list_del(&t->th_list); + kfree(t); + return PTR_ERR(p); + } + kthread_bind(p, cpu); + t->tsk = p; + + pe = create_proc_entry(t->tsk->comm, 0600, pg_proc_dir); if (!pe) { printk("pktgen: cannot create %s/%s procfs entry.\n", - PG_PROC_DIR, t->name); + PG_PROC_DIR, t->tsk->comm); + kthread_stop(p); + list_del(&t->th_list); kfree(t); return -EINVAL; } @@ -3548,21 +3505,7 @@ static int __init pktgen_create_thread(const char *name, int cpu) pe->proc_fops = &pktgen_thread_fops; pe->data = t; - INIT_LIST_HEAD(&t->if_list); - - list_add_tail(&t->th_list, &pktgen_threads); - - t->removed = 0; - - err = kernel_thread((void *)pktgen_thread_worker, (void *)t, - CLONE_FS | CLONE_FILES | CLONE_SIGHAND); - if (err < 0) { - printk("pktgen: kernel_thread() failed for cpu %d\n", t->cpu); - remove_proc_entry(t->name, pg_proc_dir); - list_del(&t->th_list); - kfree(t); - return err; - } + wake_up_process(p); return 0; } @@ -3643,10 +3586,8 @@ static int __init pg_init(void) for_each_online_cpu(cpu) { int err; - char buf[30]; - sprintf(buf, "kpktgend_%i", cpu); - err = pktgen_create_thread(buf, cpu); + err = pktgen_create_thread(cpu); if (err) printk("pktgen: WARNING: Cannot create thread for cpu %d (%d)\n", cpu, err); @@ -3674,9 +3615,8 @@ static void __exit pg_cleanup(void) list_for_each_safe(q, n, &pktgen_threads) { t = list_entry(q, struct pktgen_thread, th_list); - t->control |= (T_TERMINATE); - - wait_event_interruptible_timeout(queue, (t->removed == 1), HZ); + kthread_stop(t->tsk); + kfree(t); } /* Un-register us from receiving netdevice events */ -- 2.20.1