Commit 800977f6 authored by Cai Huoqing's avatar Cai Huoqing Committed by Linus Torvalds
Browse files

kthread: add the helper function kthread_run_on_cpu() 

Add a new helper function kthread_run_on_cpu(), which includes
kthread_create_on_cpu/wake_up_process().

In some cases, use kthread_run_on_cpu() directly instead of
kthread_create_on_node/kthread_bind/wake_up_process() or
kthread_create_on_cpu/wake_up_process() or
kthreadd_create/kthread_bind/wake_up_process() to simplify the code.

[akpm@linux-foundation.org: export kthread_create_on_cpu to modules]

Link: https://lkml.kernel.org/r/20211022025711.3673-2-caihuoqing@baidu.com


Signed-off-by: default avatarCai Huoqing <caihuoqing@baidu.com>
Cc: Bernard Metzler <bmt@zurich.ibm.com>
Cc: Cai Huoqing <caihuoqing@baidu.com>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent df0cc57e

include/linux/kthread.h

+25 −0
Original line number Diff line number Diff line
@@ -56,6 +56,31 @@ bool kthread_is_per_cpu(struct task_struct *k); 
	__k;								   \

})



/**

 * kthread_run_on_cpu - create and wake a cpu bound thread.

 * @threadfn: the function to run until signal_pending(current).

 * @data: data ptr for @threadfn.

 * @cpu: The cpu on which the thread should be bound,

 * @namefmt: printf-style name for the thread. Format is restricted

 *	     to "name.*%u". Code fills in cpu number.

 *

 * Description: Convenient wrapper for kthread_create_on_cpu()

 * followed by wake_up_process().  Returns the kthread or

 * ERR_PTR(-ENOMEM).

 */

static inline struct task_struct *

kthread_run_on_cpu(int (*threadfn)(void *data), void *data,

			unsigned int cpu, const char *namefmt)

{

	struct task_struct *p;



	p = kthread_create_on_cpu(threadfn, data, cpu, namefmt);

	if (!IS_ERR(p))

		wake_up_process(p);



	return p;

}



void free_kthread_struct(struct task_struct *k);

void kthread_bind(struct task_struct *k, unsigned int cpu);

void kthread_bind_mask(struct task_struct *k, const struct cpumask *mask);

kernel/kthread.c

+1 −0
Original line number Diff line number Diff line
@@ -523,6 +523,7 @@ struct task_struct *kthread_create_on_cpu(int (*threadfn)(void *data), 
	to_kthread(p)->cpu = cpu;

	return p;

}

EXPORT_SYMBOL(kthread_create_on_cpu);



void kthread_set_per_cpu(struct task_struct *k, int cpu)

{