On Mon, 7 Sep 2009, 홍신 shin hong wrote: > sdio_irq_therad() is spawned as a sdio_card_irq_get(). > This thread is stopped by sdio_card_irq_put(). > > sdio_irq_thread() finishes its do-while iteration > when kthread_should_stop() returns true > or a condition is satisfied (break statements at line 106) > > For the later case, if sdio_irq_thread() is finished > before kthread_should_stop() returns false. > > In that situation, if other thread invokes kthread_stop(), > the caller of kthread_stop() might have a problem (waiting indefinitely). No. First of all, you get one instance of sdio_irq_thread() for each card. And if a card has multiple functions, then multiple sdio_card_irq_get() and sdio_card_irq_put() are expected, and they should be balanced as well. So, when the last user of SDIO card interrupt calls sdio_card_irq_put(), then kthread_stop() is called on the IRQ thread, meaning that the kthread_should_stop condition is made true and the thread awakened, and then its termination is waited for. If the thread terminated itself then there is simply no waiting to do. Nicolas
