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SubjectRe: [PATCH v1 3/5] mm: ptdump: Provide page size to notepage()
Date
Hi Christophe,

> static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
> - u64 val)
> + u64 val, unsigned long page_size)

Compilers can warn about unused parameters at -Wextra level. However,
reading scripts/Makefile.extrawarn it looks like the warning is
explicitly _disabled_ in the kernel at W=1 and not reenabled at W=2 or
W=3. So I guess this is fine...

> @@ -126,7 +126,7 @@ static int ptdump_hole(unsigned long addr, unsigned long next,
> {
> struct ptdump_state *st = walk->private;
>
> - st->note_page(st, addr, depth, 0);
> + st->note_page(st, addr, depth, 0, 0);

I know it doesn't matter at this point, but I'm not really thrilled by
the idea of passing 0 as the size here. Doesn't the hole have a known
page size?

>
> return 0;
> }
> @@ -153,5 +153,5 @@ void ptdump_walk_pgd(struct ptdump_state *st, struct mm_struct *mm, pgd_t *pgd)
> mmap_read_unlock(mm);
>
> /* Flush out the last page */
> - st->note_page(st, 0, -1, 0);
> + st->note_page(st, 0, -1, 0, 0);

I'm more OK with the idea of passing 0 as the size when the depth is -1
(don't know): if we don't know the depth we conceptually can't know the
page size.

Regards,
Daniel

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