Re: [PATCH v4] mm: cma: support sysfs

Greg Kroah-Hartman
2021-03-19T13:48:30Z

On Fri, Mar 19, 2021 at 04:45:21PM +0300, Dmitry Osipenko wrote:
> 19.03.2021 16:42, Greg Kroah-Hartman пишет:
> > On Fri, Mar 19, 2021 at 04:39:41PM +0300, Dmitry Osipenko wrote:
> >> 19.03.2021 15:44, Dmitry Osipenko пишет:
> >> ...
> >>>> #include <linux/debugfs.h>
> >>>> +#include <linux/kobject.h>
> >>>> +
> >>>> +struct cma_stat {
> >>>> + spinlock_t lock;
> >>>> + /* the number of CMA page successful allocations */
> >>>> + unsigned long nr_pages_succeeded;
> >>>> + /* the number of CMA page allocation failures */
> >>>> + unsigned long nr_pages_failed;
> >>>> + struct kobject kobj;
> >>>> +};
> >>>>
> >>>> struct cma {
> >>>> unsigned long base_pfn;
> >>>> @@ -16,6 +26,9 @@ struct cma {
> >>>> struct debugfs_u32_array dfs_bitmap;
> >>>> #endif
> >>>> char name[CMA_MAX_NAME];
> >>>> +#ifdef CONFIG_CMA_SYSFS
> >>>> + struct cma_stat *stat;
> >>>> +#endif
> >>
> >> What is the point of allocating stat dynamically?
> >
> > Because static kobjects make me cry.
> >
>
> I meant that it's already a part of struct cma, it looks like the stat
> could be embedded into struct cma and then kobj could be initialized
> separately.

But that structure is statically allocated, so it can not be. This has
been discussed in the past threads for when this was reviewed if you are
curious :)

thanks,

greg k-h