2021-10-21 12:30:33

by Cai,Huoqing

[permalink] [raw]
Subject: [PATCH v2 1/6] kthread: Add the helper macro kthread_run_on_cpu()

the helper macro kthread_run_on_cpu() inculdes
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.

Signed-off-by: Cai Huoqing <[email protected]>
---
v1->v2:
*Remove cpu_to_node from kthread_create_on_cpu params.
*Updated the macro description comment.

include/linux/kthread.h | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/include/linux/kthread.h b/include/linux/kthread.h
index 346b0f269161..dfd125523aa9 100644
--- a/include/linux/kthread.h
+++ b/include/linux/kthread.h
@@ -56,6 +56,27 @@ 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).
+ */
+#define kthread_run_on_cpu(threadfn, data, cpu, namefmt) \
+({ \
+ struct task_struct *__k \
+ = kthread_create_on_cpu(threadfn, data, cpu, namefmt); \
+ if (!IS_ERR(__k)) \
+ wake_up_process(__k); \
+ __k; \
+})
+
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);
--
2.25.1