userfaultfd: remove set but not used variable 'vm_alloc_shared'

mm/userfaultfd.c: In function `__mcopy_atomic_hugetlb':
mm/userfaultfd.c:284:6: warning: variable `vm_alloc_shared' set but not used [-Wunused-but-set-variable]
  int vm_alloc_shared = dst_vma->vm_flags & VM_SHARED;
      ^~~~~~~~~~~~~~~

commit 1786d0012620 ("mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY")
left behind this.

Link: https://lkml.kernel.org/r/20210601141610.28332-1-yuehaibing@huawei.com
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index e13a0492b7ba95fd783abbf69c16eaf1ddc955aa..da5535d2d99033965df01c1c81d046be3029177d 100644 (file)
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -209,7 +209,6 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
                                              unsigned long len,
                                              enum mcopy_atomic_mode mode)
 {
-       int vm_alloc_shared = dst_vma->vm_flags & VM_SHARED;
        int vm_shared = dst_vma->vm_flags & VM_SHARED;
        ssize_t err;
        pte_t *dst_pte;
@@ -308,7 +307,6 @@ retry:
 
                mutex_unlock(&hugetlb_fault_mutex_table[hash]);
                i_mmap_unlock_read(mapping);
-               vm_alloc_shared = vm_shared;
 
                cond_resched();