Messages in this thread | | | Date | Wed, 24 Mar 2021 04:34:34 +0000 | From | Matthew Wilcox <> | Subject | Re: [PATCH v5] mm: cma: support sysfs |
| |
On Tue, Mar 23, 2021 at 08:31:31PM -0700, Minchan Kim wrote: > On Wed, Mar 24, 2021 at 03:02:24AM +0000, Matthew Wilcox wrote: > > On Tue, Mar 23, 2021 at 12:50:50PM -0700, Minchan Kim wrote: > > > + /* the number of CMA page successful allocations */ > > > + atomic64_t nr_pages_succeeded; > > > > > +void cma_sysfs_alloc_pages_count(struct cma *cma, size_t count) > > > +{ > > > + atomic64_add(count, &cma->nr_pages_succeeded); > > > +} > > > > I don't understand. A size_t is a byte count. But the variable is called > > 'nr_pages'. So which is it, a byte count or a page count? > > It's page count. I followed the cma_alloc interface since it has > size_t count variable for nr_pages.
That's very confusing. cma_alloc is wrong; if it needs to be an unsigned long, that's fine. But it shouldn't be size_t.
7.17 of n1256 defines:
size_t which is the unsigned integer type of the result of the sizeof operator
Do you want to submit a patch to fix cma_alloc as well?
> Let's go with unsigned long nr_pages: > void cma_sysfs_alloc_pages_count(struct cma *cma, unsigned long > nr_pages)
Works for me!
| |