From: Petr Mladek <pmladek@xxxxxxxx> Subject: kthread: allow to call __kthread_create_on_node() with va_list args kthread_create_on_node() implements a bunch of logic to create the kthread. It is already called by kthread_create_on_cpu(). We are going to extend the kthread worker API and will need to call kthread_create_on_node() with va_list args there. This patch does only a refactoring and does not modify the existing behavior. Link: http://lkml.kernel.org/r/1470754545-17632-5-git-send-email-pmladek@xxxxxxxx Signed-off-by: Petr Mladek <pmladek@xxxxxxxx> Acked-by: Tejun Heo <tj@xxxxxxxxxx> Cc: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> Cc: Josh Triplett <josh@xxxxxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Jiri Kosina <jkosina@xxxxxxx> Cc: Borislav Petkov <bp@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/kthread.c | 72 ++++++++++++++++++++++++++------------------- 1 file changed, 42 insertions(+), 30 deletions(-) diff -puN kernel/kthread.c~kthread-allow-to-call-__kthread_create_on_node-with-va_list-args kernel/kthread.c --- a/kernel/kthread.c~kthread-allow-to-call-__kthread_create_on_node-with-va_list-args +++ a/kernel/kthread.c @@ -244,33 +244,10 @@ static void create_kthread(struct kthrea } } -/** - * kthread_create_on_node - create a kthread. - * @threadfn: the function to run until signal_pending(current). - * @data: data ptr for @threadfn. - * @node: task and thread structures for the thread are allocated on this node - * @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(). The new thread has SCHED_NORMAL policy and - * is affine to all CPUs. - * - * If thread is going to be bound on a particular cpu, give its node - * in @node, to get NUMA affinity for kthread stack, or else give NUMA_NO_NODE. - * 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 no one 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) or ERR_PTR(-EINTR). - */ -struct task_struct *kthread_create_on_node(int (*threadfn)(void *data), - void *data, int node, - const char namefmt[], - ...) +static struct task_struct *__kthread_create_on_node(int (*threadfn)(void *data), + void *data, int node, + const char namefmt[], + va_list args) { DECLARE_COMPLETION_ONSTACK(done); struct task_struct *task; @@ -311,11 +288,8 @@ struct task_struct *kthread_create_on_no task = create->result; if (!IS_ERR(task)) { static const struct sched_param param = { .sched_priority = 0 }; - va_list args; - va_start(args, namefmt); vsnprintf(task->comm, sizeof(task->comm), namefmt, args); - va_end(args); /* * root may have changed our (kthreadd's) priority or CPU mask. * The kernel thread should not inherit these properties. @@ -326,6 +300,44 @@ struct task_struct *kthread_create_on_no kfree(create); return task; } + +/** + * kthread_create_on_node - create a kthread. + * @threadfn: the function to run until signal_pending(current). + * @data: data ptr for @threadfn. + * @node: task and thread structures for the thread are allocated on this node + * @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(). The new thread has SCHED_NORMAL policy and + * is affine to all CPUs. + * + * If thread is going to be bound on a particular cpu, give its node + * in @node, to get NUMA affinity for kthread stack, or else give NUMA_NO_NODE. + * 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 no one 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) or ERR_PTR(-EINTR). + */ +struct task_struct *kthread_create_on_node(int (*threadfn)(void *data), + void *data, int node, + const char namefmt[], + ...) +{ + struct task_struct *task; + va_list args; + + va_start(args, namefmt); + task = __kthread_create_on_node(threadfn, data, node, namefmt, args); + va_end(args); + + return task; +} EXPORT_SYMBOL(kthread_create_on_node); static void __kthread_bind_mask(struct task_struct *p, const struct cpumask *mask, long state) _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
