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]>
---
include/linux/kthread.h | 22 ++++++++++++++++++++++
1 file changed, 22 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 +56,28 @@ 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_node()
+ * 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_to_node(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
On Thu, 21 Oct 2021 20:01:30 +0800
Cai Huoqing <[email protected]> wrote:
> the helper macro kthread_run_on_cpu() inculdes
"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.
>
> Signed-off-by: Cai Huoqing <[email protected]>
> ---
> include/linux/kthread.h | 22 ++++++++++++++++++++++
> 1 file changed, 22 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 +56,28 @@ 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_node()
> + * followed by wake_up_process(). Returns the kthread or
> + * ERR_PTR(-ENOMEM).
> + */
> +#define kthread_run_on_cpu(threadfn, data, cpu, namefmt) \
Why is this a macro and not a static inline function?
-- Steve
> +({ \
> + struct task_struct *__k \
> + = kthread_create_on_cpu(threadfn, data, cpu_to_node(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);
On 21 10月 21 09:10:01, Steven Rostedt wrote:
> On Thu, 21 Oct 2021 20:01:30 +0800
> Cai Huoqing <[email protected]> wrote:
>
> > the helper macro kthread_run_on_cpu() inculdes
>
> "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.
> >
> > Signed-off-by: Cai Huoqing <[email protected]>
> > ---
> > include/linux/kthread.h | 22 ++++++++++++++++++++++
> > 1 file changed, 22 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 +56,28 @@ 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_node()
> > + * followed by wake_up_process(). Returns the kthread or
> > + * ERR_PTR(-ENOMEM).
> > + */
> > +#define kthread_run_on_cpu(threadfn, data, cpu, namefmt) \
>
> Why is this a macro and not a static inline function?
>
> -- Steve
Hi,Thanks for your feedback,
I think using static inline function is nice, but here try to keep
consistent with the other macros,
sush as kthread_create/kthread_init_work...
Thanks,
Cai.
>
> > +({ \
> > + struct task_struct *__k \
> > + = kthread_create_on_cpu(threadfn, data, cpu_to_node(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);
>
On Thu, 21 Oct 2021 21:53:12 +0800
Cai Huoqing <[email protected]> wrote:
> > > +/**
> > > + * 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_node()
> > > + * followed by wake_up_process(). Returns the kthread or
> > > + * ERR_PTR(-ENOMEM).
> > > + */
> > > +#define kthread_run_on_cpu(threadfn, data, cpu, namefmt) \
> >
> > Why is this a macro and not a static inline function?
> >
> > -- Steve
> Hi,Thanks for your feedback,
>
> I think using static inline function is nice, but here try to keep
> consistent with the other macros,
> sush as kthread_create/kthread_init_work...
Which they did because they didn't want to use va_list to have variable
arguments, which you don't have.
Which begs the question, should you?
-- Steve
On 21 10月 21 09:58:58, Steven Rostedt wrote:
> On Thu, 21 Oct 2021 21:53:12 +0800
> Cai Huoqing <[email protected]> wrote:
>
> > > > +/**
> > > > + * 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_node()
> > > > + * followed by wake_up_process(). Returns the kthread or
> > > > + * ERR_PTR(-ENOMEM).
> > > > + */
> > > > +#define kthread_run_on_cpu(threadfn, data, cpu, namefmt) \
> > >
> > > Why is this a macro and not a static inline function?
> > >
> > > -- Steve
> > Hi,Thanks for your feedback,
> >
> > I think using static inline function is nice, but here try to keep
> > consistent with the other macros,
> > sush as kthread_create/kthread_init_work...
>
> Which they did because they didn't want to use va_list to have variable
> arguments, which you don't have.
>
> Which begs the question, should you?
>
> -- Steve
Hi, Thanks your reply.
I get it, V3 here:
https://lore.kernel.org/lkml/[email protected]/
Thanks,
Cai