Re: [PATCH v3 1/6] kthread: Add the helper function kthread_run_on_cpu()

From: Steven Rostedt
Date: Tue Nov 16 2021 - 16:01:56 EST


On Tue, 26 Oct 2021 08:32:30 +0000
"Cai,Huoqing" <caihuoqing@xxxxxxxxx> wrote:

> Hello,
> Just a ping, to see if there are any more comments :-P

I have no real issue with this patch set. As it seems to be a generic clean
up, perhaps Andrew might like to take a look at it, and if he's fine with
it, he can take it through his tree?

-- Steve


> > -----Original Message-----
> > From: Cai,Huoqing <caihuoqing@xxxxxxxxx>
> > Sent: 2021年10月22日 10:57
> > Subject: [PATCH v3 1/6] kthread: Add the helper function kthread_run_on_cpu()
> >
> > the helper function kthread_run_on_cpu() 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 <caihuoqing@xxxxxxxxx>
> > ---
> > v1->v2:
> > *Remove cpu_to_node from kthread_create_on_cpu params.
> > *Updated the macro description comment.
> > v2->v3:
> > *Convert this helper macro to static inline function
> > *Fix typo in changelog
> >
> > v1 link:
> > https://lore.kernel.org/lkml/20211021120135.3003-2-
> > caihuoqing@xxxxxxxxx/
> > v2 link:
> > https://lore.kernel.org/lkml/20211021122758.3092-2-
> > caihuoqing@xxxxxxxxx/
> >
> > include/linux/kthread.h | 25 +++++++++++++++++++++++++
> > 1 file changed, 25 insertions(+)
> >
> > diff --git a/include/linux/kthread.h b/include/linux/kthread.h
> > index 346b0f269161..db47aae7c481 100644
> > --- a/include/linux/kthread.h
> > +++ b/include/linux/kthread.h
> > @@ -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);
> > --
> > 2.25.1
>