diff --git a/include/sound/seq_kernel.h b/include/sound/seq_kernel.h index 2398521f0998..eea5400fe373 100644 --- a/include/sound/seq_kernel.h +++ b/include/sound/seq_kernel.h @@ -108,9 +108,13 @@ int snd_seq_event_port_detach(int client, int port); #ifdef CONFIG_MODULES void snd_seq_autoload_lock(void); void snd_seq_autoload_unlock(void); +void snd_seq_autoload_init(void); +#define snd_seq_autoload_exit() snd_seq_autoload_lock() #else #define snd_seq_autoload_lock() #define snd_seq_autoload_unlock() +#define snd_seq_autoload_init() +#define snd_seq_autoload_exit() #endif #endif /* __SOUND_SEQ_KERNEL_H */ diff --git a/sound/core/seq/seq.c b/sound/core/seq/seq.c index 712110561082..bebdd2e920ca 100644 --- a/sound/core/seq/seq.c +++ b/sound/core/seq/seq.c @@ -110,6 +110,7 @@ static int __init alsa_seq_init(void) if ((err = snd_seq_system_client_init()) < 0) goto error; + snd_seq_autoload_init(); error: snd_seq_autoload_unlock(); return err; @@ -131,6 +132,8 @@ static void __exit alsa_seq_exit(void) /* release event memory */ snd_sequencer_memory_done(); + + snd_seq_autoload_exit(); } module_init(alsa_seq_init) diff --git a/sound/core/seq/seq_device.c b/sound/core/seq/seq_device.c index 775ea9390110..a8e2c6016800 100644 --- a/sound/core/seq/seq_device.c +++ b/sound/core/seq/seq_device.c @@ -56,6 +56,7 @@ MODULE_LICENSE("GPL"); #define DRIVER_LOADED (1<<0) #define DRIVER_REQUESTED (1<<1) #define DRIVER_LOCKED (1<<2) +#define DRIVER_REQUESTING (1<<3) struct ops_list { char id[ID_LEN]; /* driver id */ @@ -127,7 +128,7 @@ static void snd_seq_device_info(struct snd_info_entry *entry, #ifdef CONFIG_MODULES /* avoid auto-loading during module_init() */ -static atomic_t snd_seq_in_init = ATOMIC_INIT(0); +static atomic_t snd_seq_in_init = ATOMIC_INIT(1); /* blocked as default */ void snd_seq_autoload_lock(void) { atomic_inc(&snd_seq_in_init); @@ -137,32 +138,72 @@ void snd_seq_autoload_unlock(void) { atomic_dec(&snd_seq_in_init); } + +static void autoload_drivers(void) +{ + /* avoid reentrance */ + if (atomic_inc_return(&snd_seq_in_init) == 1) { + struct ops_list *ops; + + mutex_lock(&ops_mutex); + list_for_each_entry(ops, &opslist, list) { + if ((ops->driver & DRIVER_REQUESTING) && + !(ops->driver & DRIVER_REQUESTED)) { + ops->used++; + mutex_unlock(&ops_mutex); + ops->driver |= DRIVER_REQUESTED; + request_module("snd-%s", ops->id); + mutex_lock(&ops_mutex); + ops->used--; + } + } + mutex_unlock(&ops_mutex); + } + atomic_dec(&snd_seq_in_init); +} + +static void call_autoload(struct work_struct *work) +{ + autoload_drivers(); +} + +static DECLARE_WORK(autoload_work, call_autoload); + +static void try_autoload(struct ops_list *ops) +{ + if (!ops->driver) { + ops->driver |= DRIVER_REQUESTING; + schedule_work(&autoload_work); + } +} + +static void queue_autoload_drivers(void) +{ + struct ops_list *ops; + + mutex_lock(&ops_mutex); + list_for_each_entry(ops, &opslist, list) + try_autoload(ops); + mutex_unlock(&ops_mutex); +} + +void snd_seq_autoload_init(void) +{ + atomic_dec(&snd_seq_in_init); +#ifdef CONFIG_SND_SEQUENCER_MODULE + /* initial autoload only when snd-seq is a module */ + queue_autoload_drivers(); +#endif +} +#else +#define try_autoload(ops) /* NOP */ #endif void snd_seq_device_load_drivers(void) { #ifdef CONFIG_MODULES - struct ops_list *ops; - - /* Calling request_module during module_init() - * may cause blocking. - */ - if (atomic_read(&snd_seq_in_init)) - return; - - mutex_lock(&ops_mutex); - list_for_each_entry(ops, &opslist, list) { - if (! (ops->driver & DRIVER_LOADED) && - ! (ops->driver & DRIVER_REQUESTED)) { - ops->used++; - mutex_unlock(&ops_mutex); - ops->driver |= DRIVER_REQUESTED; - request_module("snd-%s", ops->id); - mutex_lock(&ops_mutex); - ops->used--; - } - } - mutex_unlock(&ops_mutex); + queue_autoload_drivers(); + flush_work(&autoload_work); #endif } @@ -214,13 +255,14 @@ int snd_seq_device_new(struct snd_card *card, int device, char *id, int argsize, ops->num_devices++; mutex_unlock(&ops->reg_mutex); - unlock_driver(ops); - if ((err = snd_device_new(card, SNDRV_DEV_SEQUENCER, dev, &dops)) < 0) { snd_seq_device_free(dev); return err; } + try_autoload(ops); + unlock_driver(ops); + if (result) *result = dev; @@ -554,6 +596,9 @@ static int __init alsa_seq_device_init(void) static void __exit alsa_seq_device_exit(void) { +#ifdef CONFIG_MODULES + cancel_work_sync(&autoload_work); +#endif remove_drivers(); #ifdef CONFIG_PROC_FS snd_info_free_entry(info_entry); @@ -570,6 +615,7 @@ EXPORT_SYMBOL(snd_seq_device_new); EXPORT_SYMBOL(snd_seq_device_register_driver); EXPORT_SYMBOL(snd_seq_device_unregister_driver); #ifdef CONFIG_MODULES +EXPORT_SYMBOL(snd_seq_autoload_init); EXPORT_SYMBOL(snd_seq_autoload_lock); EXPORT_SYMBOL(snd_seq_autoload_unlock); #endif