On 16 June 2014 11:09, micky <micky_ching@xxxxxxxxxxxxxx> wrote: > On 06/16/2014 04:42 PM, Ulf Hansson wrote: >>> >>> @@ -36,7 +37,10 @@ struct realtek_pci_sdmmc { >>> > struct rtsx_pcr *pcr; >>> > struct mmc_host *mmc; >>> > struct mmc_request *mrq; >>> >+ struct workqueue_struct *workq; >>> >+#define SDMMC_WORKQ_NAME "rtsx_pci_sdmmc_workq" >>> > >>> >+ struct work_struct work; >> >> I am trying to understand why you need a work/workqueue to implement >> this feature. Is that really the case? >> >> Could you elaborate on the reasons? > > Hi Uffe, > > we need return as fast as possible in mmc_host_ops request(ops->request) > callback, > so the mmc core can continue handle next request. > when next request everything is ready, it will wait previous done(if not > done), > then call ops->request(). > > we can't use atomic context, because we use mutex_lock() to protect ops->request should never executed in atomic context. Is that your concern? > resource, and we have to hold the lock during handle request. > So I use workq, we just queue a work and return in ops->request(), > The mmc core can continue without blocking at ops->request(). > > Best Regards. > micky. Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html