Using cast_if_type() we can have a callback funciton either of the exactly correct type to take "data", or to take a void *.
Signed-off-by: Rusty Russell <[EMAIL PROTECTED]> --- include/linux/kthread.h | 30 +++++++++++++++++++++++++++--- kernel/kthread.c | 29 +++++------------------------ 2 files changed, 32 insertions(+), 27 deletions(-) diff -r 5748be68d6ee include/linux/kthread.h --- a/include/linux/kthread.h Wed Jan 23 12:08:28 2008 +1100 +++ b/include/linux/kthread.h Wed Jan 23 12:14:00 2008 +1100 @@ -4,9 +4,33 @@ #include <linux/err.h> #include <linux/sched.h> -struct task_struct *kthread_create(int (*threadfn)(void *data), - void *data, - const char namefmt[], ...); +/** + * kthread_create - create a kthread. + * @threadfn: the function to run until signal_pending(current). + * @data: data ptr for @threadfn. + * @namefmt: printf-style name for the thread. + * + * Description: This helper function creates and names a kernel + * thread. The thread will be stopped: use wake_up_process() to start + * it. See also kthread_run(), kthread_create_on_cpu(). + * + * When woken, the thread will run @threadfn() with @data as its + * argument. @threadfn() can either call do_exit() directly if it is a + * standalone thread for which noone will call kthread_stop(), or + * return when 'kthread_should_stop()' is true (which means + * kthread_stop() has been called). The return value should be zero + * or a negative error number; it will be passed to kthread_stop(). + * + * Returns a task_struct or ERR_PTR(-ENOMEM). + */ +#define kthread_create(threadfn, data, namefmt...) \ + __kthread_create(cast_if_type((threadfn), int(*)(typeof(data)), \ + int(*)(void *)), \ + (data), namefmt) + +struct task_struct *__kthread_create(int (*threadfn)(void *data), + void *data, + const char namefmt[], ...); /** * kthread_run - create and wake a thread. diff -r 5748be68d6ee kernel/kthread.c --- a/kernel/kthread.c Wed Jan 23 12:08:28 2008 +1100 +++ b/kernel/kthread.c Wed Jan 23 12:14:00 2008 +1100 @@ -102,29 +102,10 @@ static void create_kthread(struct kthrea complete(&create->done); } -/** - * kthread_create - create a kthread. - * @threadfn: the function to run until signal_pending(current). - * @data: data ptr for @threadfn. - * @namefmt: printf-style name for the thread. - * - * Description: This helper function creates and names a kernel - * thread. The thread will be stopped: use wake_up_process() to start - * it. See also kthread_run(), kthread_create_on_cpu(). - * - * When woken, the thread will run @threadfn() with @data as its - * argument. @threadfn() can either call do_exit() directly if it is a - * standalone thread for which noone will call kthread_stop(), or - * return when 'kthread_should_stop()' is true (which means - * kthread_stop() has been called). The return value should be zero - * or a negative error number; it will be passed to kthread_stop(). - * - * Returns a task_struct or ERR_PTR(-ENOMEM). - */ -struct task_struct *kthread_create(int (*threadfn)(void *data), - void *data, - const char namefmt[], - ...) +struct task_struct *__kthread_create(int (*threadfn)(void *data), + void *data, + const char namefmt[], + ...) { struct kthread_create_info create; @@ -149,7 +130,7 @@ struct task_struct *kthread_create(int ( } return create.result; } -EXPORT_SYMBOL(kthread_create); +EXPORT_SYMBOL(__kthread_create); /** * kthread_bind - bind a just-created kthread to a cpu. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/