From: Cai Huoqing <caihuoqing@baidu.com>
Date: Fri, 14 Jan 2022 14:02:52 -0800
Subject: kthread: add the helper function kthread_run_on_cpu()
Patch-mainline: v5.17-rc1
Git-commit: 800977f6f32e452cba6b04ef21d2f5383ca29209
References: jsc#PED-1503
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: Cai 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
include/linux/kthread.h | 25 +++++++++++++++++++++++++
kernel/kthread.c | 1 +
2 files changed, 26 insertions(+)
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h
@@ -56,6 +56,31 @@ bool kthread_is_per_cpu(struct task_stru
__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);
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -523,6 +523,7 @@ struct task_struct *kthread_create_on_cp
to_kthread(p)->cpu = cpu;
return p;
}
+EXPORT_SYMBOL(kthread_create_on_cpu);
void kthread_set_per_cpu(struct task_struct *k, int cpu)
{