Re: [XEN PATCH 1/5] xen/common: address violations of MISRA C:2012 Rule 8.2

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Fri, 17 Nov 2023, Federico Serafini wrote:
> diff --git a/xen/common/stop_machine.c b/xen/common/stop_machine.c
> index 3adbe380de..398cfd507c 100644
> --- a/xen/common/stop_machine.c
> +++ b/xen/common/stop_machine.c
> @@ -46,7 +46,7 @@ struct stopmachine_data {
>  
>      unsigned int fn_cpu;
>      int fn_result;
> -    int (*fn)(void *);
> +    int (*fn)(void *data);
>      void *fn_data;
>  };

At least one of the possible function used here calls the parameter
"arg", see take_cpu_down. But I don't think it is a MISRA requirement to
also harmonize those?


> @@ -73,7 +73,7 @@ static void stopmachine_wait_state(void)
>   * mandatory to be called only on an idle vcpu, as otherwise active core
>   * scheduling might hang.
>   */
> -int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu)
> +int stop_machine_run(int (*fn)(void *data), void *data, unsigned int cpu)
>  {
>      unsigned int i, nr_cpus;
>      unsigned int this = smp_processor_id();
> diff --git a/xen/common/tasklet.c b/xen/common/tasklet.c
> index 3ad67b5c24..3649798e6b 100644
> --- a/xen/common/tasklet.c
> +++ b/xen/common/tasklet.c
> @@ -199,7 +199,7 @@ static void migrate_tasklets_from_cpu(unsigned int cpu, 
> struct list_head *list)
>      spin_unlock_irqrestore(&tasklet_lock, flags);
>  }
>  
> -void tasklet_init(struct tasklet *t, void (*func)(void *), void *data)
> +void tasklet_init(struct tasklet *t, void (*func)(void *data), void *data)
>  {
>      memset(t, 0, sizeof(*t));
>      INIT_LIST_HEAD(&t->list);
> @@ -208,7 +208,8 @@ void tasklet_init(struct tasklet *t, void (*func)(void 
> *), void *data)
>      t->data = data;
>  }
>  
> -void softirq_tasklet_init(struct tasklet *t, void (*func)(void *), void 
> *data)
> +void softirq_tasklet_init(struct tasklet *t,
> +                          void (*func)(void *data), void *data)
>  {
>      tasklet_init(t, func, data);
>      t->is_softirq = 1;
> diff --git a/xen/common/timer.c b/xen/common/timer.c
> index 0fddfa7487..bf7792dcb3 100644
> --- a/xen/common/timer.c
> +++ b/xen/common/timer.c
> @@ -291,7 +291,7 @@ static bool active_timer(const struct timer *timer)
>  
>  void init_timer(
>      struct timer *timer,
> -    void        (*function)(void *),
> +    void        (*function)(void *data),
>      void         *data,
>      unsigned int  cpu)
>  {
> @@ -441,7 +441,7 @@ void kill_timer(struct timer *timer)
>  
>  static void execute_timer(struct timers *ts, struct timer *t)
>  {
> -    void (*fn)(void *) = t->function;
> +    void (*fn)(void *data) = t->function;
>      void *data = t->data;
>  
>      t->status = TIMER_STATUS_inactive;
> diff --git a/xen/include/xen/rangeset.h b/xen/include/xen/rangeset.h
> index 135f33f606..390f7b6082 100644
> --- a/xen/include/xen/rangeset.h
> +++ b/xen/include/xen/rangeset.h
> @@ -68,7 +68,7 @@ bool_t __must_check rangeset_overlaps_range(
>      struct rangeset *r, unsigned long s, unsigned long e);
>  int rangeset_report_ranges(
>      struct rangeset *r, unsigned long s, unsigned long e,
> -    int (*cb)(unsigned long s, unsigned long e, void *), void *ctxt);
> +    int (*cb)(unsigned long s, unsigned long e, void *data), void *ctxt);

Also here some of the functions use "arg" instead of ctxt


>  /*
>   * Note that the consume function can return an error value apart from
> @@ -77,7 +77,7 @@ int rangeset_report_ranges(
>   */
>  int rangeset_consume_ranges(struct rangeset *r,
>                              int (*cb)(unsigned long s, unsigned long e,
> -                                      void *, unsigned long *c),
> +                                      void *ctxt, unsigned long *c),
>                              void *ctxt);

Also here some of the functions use "dom" like irq_remove_cb.


But I actually like the patch as is, so if that's OK from a MISRA point
of view then I would give my reviewed-by.