[PATCH v2] mm: remove redundant check non_swap_entry()

From: Ralph Campbell
Date: Mon Jun 15 2020 - 13:54:26 EST


In zap_pte_range(), the check for non_swap_entry() and
is_device_private_entry() is unnecessary since the latter is sufficient
to determine if the page is a device private page. Remove the test for
non_swap_entry() to simplify the code and for clarity.

Signed-off-by: Ralph Campbell <rcampbell@xxxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
---

This is based on the linux 5.8.0-rc1 tree and is intended for Andrew's mm
tree. There is no rush so it could go into 5.9 but I think it is safe
enough to go into an rc after the patch is reviewed.

Changes since v1:
Updated the change log to be more clear.
Added Jason Gunthorpe's reviewed-by.
Rebased to 5.8.0-rc1

mm/memory.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/memory.c b/mm/memory.c
index dc7f3543b1fd..bdbb4f97e7d0 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1098,7 +1098,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
}

entry = pte_to_swp_entry(ptent);
- if (non_swap_entry(entry) && is_device_private_entry(entry)) {
+ if (is_device_private_entry(entry)) {
struct page *page = device_private_entry_to_page(entry);

if (unlikely(details && details->check_mapping)) {
--
2.20.1