From 7104e2d5a85b4b786d6a63568beffe1e185547bb Mon Sep 17 00:00:00 2001 From: Pierre Ossman Date: Wed, 4 Oct 2006 02:15:41 -0700 Subject: [PATCH] [PATCH] mmc: use own work queue The MMC layer uses the standard work queue for doing card detection. As this queue is shared with other crucial subsystems, the effects of a long (and perhaps buggy) detection can cause the system to be unusable. E.g. the keyboard stops working while the detection routine is running. The solution is to add a specific mmc work queue to run the detection code in. This is similar to how other subsystems handle detection (a full kernel thread is the most common theme). Signed-off-by: Pierre Ossman Cc: Russell King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/mmc/mmc.c | 6 +++--- drivers/mmc/mmc.h | 4 ++++ drivers/mmc/mmc_sysfs.c | 35 ++++++++++++++++++++++++++++++++++- 3 files changed, 41 insertions(+), 4 deletions(-) diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index 5b9caa7978d3..ee8863c123e3 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -1166,9 +1166,9 @@ static void mmc_setup(struct mmc_host *host) void mmc_detect_change(struct mmc_host *host, unsigned long delay) { if (delay) - schedule_delayed_work(&host->detect, delay); + mmc_schedule_delayed_work(&host->detect, delay); else - schedule_work(&host->detect); + mmc_schedule_work(&host->detect); } EXPORT_SYMBOL(mmc_detect_change); @@ -1311,7 +1311,7 @@ EXPORT_SYMBOL(mmc_remove_host); */ void mmc_free_host(struct mmc_host *host) { - flush_scheduled_work(); + mmc_flush_scheduled_work(); mmc_free_host_sysfs(host); } diff --git a/drivers/mmc/mmc.h b/drivers/mmc/mmc.h index 97bae00292fa..cd5e0ab3d84b 100644 --- a/drivers/mmc/mmc.h +++ b/drivers/mmc/mmc.h @@ -18,4 +18,8 @@ struct mmc_host *mmc_alloc_host_sysfs(int extra, struct device *dev); int mmc_add_host_sysfs(struct mmc_host *host); void mmc_remove_host_sysfs(struct mmc_host *host); void mmc_free_host_sysfs(struct mmc_host *host); + +int mmc_schedule_work(struct work_struct *work); +int mmc_schedule_delayed_work(struct work_struct *work, unsigned long delay); +void mmc_flush_scheduled_work(void); #endif diff --git a/drivers/mmc/mmc_sysfs.c b/drivers/mmc/mmc_sysfs.c index a2a35fd946ee..10cc9734eaa0 100644 --- a/drivers/mmc/mmc_sysfs.c +++ b/drivers/mmc/mmc_sysfs.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include @@ -317,10 +318,41 @@ void mmc_free_host_sysfs(struct mmc_host *host) class_device_put(&host->class_dev); } +static struct workqueue_struct *workqueue; + +/* + * Internal function. Schedule work in the MMC work queue. + */ +int mmc_schedule_work(struct work_struct *work) +{ + return queue_work(workqueue, work); +} + +/* + * Internal function. Schedule delayed work in the MMC work queue. + */ +int mmc_schedule_delayed_work(struct work_struct *work, unsigned long delay) +{ + return queue_delayed_work(workqueue, work, delay); +} + +/* + * Internal function. Flush all scheduled work from the MMC work queue. + */ +void mmc_flush_scheduled_work(void) +{ + flush_workqueue(workqueue); +} static int __init mmc_init(void) { - int ret = bus_register(&mmc_bus_type); + int ret; + + workqueue = create_singlethread_workqueue("kmmcd"); + if (!workqueue) + return -ENOMEM; + + ret = bus_register(&mmc_bus_type); if (ret == 0) { ret = class_register(&mmc_host_class); if (ret) @@ -333,6 +365,7 @@ static void __exit mmc_exit(void) { class_unregister(&mmc_host_class); bus_unregister(&mmc_bus_type); + destroy_workqueue(workqueue); } module_init(mmc_init); -- 2.20.1