Hi Daniel,
Le 16/04/2021 à 01:29, Daniel Axtens a écrit :
Hi Christophe,
Which hugepd, page table entries can be at any level
and can be of any size.
Add support for them.
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
mm/ptdump.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/mm/ptdump.c b/mm/ptdump.c
index 61cd16afb1c8..6efdb8c15a7d 100644
--- a/mm/ptdump.c
+++ b/mm/ptdump.c
@@ -112,11 +112,24 @@ static int ptdump_pte_entry(pte_t *pte, unsigned long addr,
{
struct ptdump_state *st = walk->private;
pte_t val = ptep_get(pte);
+ unsigned long page_size = next - addr;
+ int level;
+
+ if (page_size >= PGDIR_SIZE)
+ level = 0;
+ else if (page_size >= P4D_SIZE)
+ level = 1;
+ else if (page_size >= PUD_SIZE)
+ level = 2;
+ else if (page_size >= PMD_SIZE)
+ level = 3;
+ else
+ level = 4;
if (st->effective_prot)
- st->effective_prot(st, 4, pte_val(val));
+ st->effective_prot(st, level, pte_val(val));
- st->note_page(st, addr, 4, pte_val(val), PAGE_SIZE);
+ st->note_page(st, addr, level, pte_val(val), page_size);
It seems to me that passing both level and page_size is a bit redundant,
but I guess it does reduce the impact on each arch's code?
Exactly, as shown above, the level can be re-calculated based on the page size, but it would be a
unnecessary impact on all architectures and would duplicate the re-calculation of the level whereas
in most cases we get it for free from the caller.
Kind regards,
Daniel
return 0;
}
--
2.25.0
