hugetlb: do not update address in huge_pmd_unshare
authorMike Kravetz <mike.kravetz@oracle.com>
Tue, 21 Jun 2022 23:56:19 +0000 (16:56 -0700)
committerakpm <akpm@linux-foundation.org>
Mon, 18 Jul 2022 00:14:34 +0000 (17:14 -0700)
commit4ddb4d91b82f4b64458fe35bc8e395c7c082ea2b
tree449484e4667b83538c62bee7a2ed993861c06250
parent1bcdb769f9e0ad7a17891772e6b5414a2945714f
hugetlb: do not update address in huge_pmd_unshare

As an optimization for loops sequentially processing hugetlb address
ranges, huge_pmd_unshare would update a passed address if it unshared a
pmd.  Updating a loop control variable outside the loop like this is
generally a bad idea.  These loops are now using hugetlb_mask_last_page to
optimize scanning when non-present ptes are discovered.  The same can be
done when huge_pmd_unshare returns 1 indicating a pmd was unshared.

Remove address update from huge_pmd_unshare.  Change the passed argument
type and update all callers.  In loops sequentially processing addresses
use hugetlb_mask_last_page to update address if pmd is unshared.

[sfr@canb.auug.org.au: fix an unused variable warning/error]
Link: https://lkml.kernel.org/r/20220622171117.70850960@canb.auug.org.au
Link: https://lkml.kernel.org/r/20220621235620.291305-4-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Will Deacon <will@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
include/linux/hugetlb.h
mm/hugetlb.c
mm/rmap.c