mm: introduce do_zap_pte_range()

This commit introduces do_zap_pte_range() to actually zap the PTEs, which
will help improve code readability and facilitate secondary checking of
the processed PTEs in the future.

No functional change.

Link: https://lkml.kernel.org/r/c3fd16807f83bb7d7a376cc6de023a9f5ead17da.1733305182.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reviewed-by: Jann Horn <jannh@google.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: Zach O'Keefe <zokeefe@google.com>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/memory.c b/mm/memory.c
index bed55f8873d5deb59a743c935c52ab239bebe9a3..378576e6b74587cb2e1f8d134f583d562dd70473 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1657,6 +1657,27 @@ static inline int zap_nonpresent_ptes(struct mmu_gather *tlb,
        return nr;
 }
 
+static inline int do_zap_pte_range(struct mmu_gather *tlb,
+                                  struct vm_area_struct *vma, pte_t *pte,
+                                  unsigned long addr, unsigned long end,
+                                  struct zap_details *details, int *rss,
+                                  bool *force_flush, bool *force_break)
+{
+       pte_t ptent = ptep_get(pte);
+       int max_nr = (end - addr) / PAGE_SIZE;
+
+       if (pte_none(ptent))
+               return 1;
+
+       if (pte_present(ptent))
+               return zap_present_ptes(tlb, vma, pte, ptent, max_nr,
+                                       addr, details, rss, force_flush,
+                                       force_break);
+
+       return zap_nonpresent_ptes(tlb, vma, pte, ptent, max_nr, addr,
+                                        details, rss);
+}
+
 static unsigned long zap_pte_range(struct mmu_gather *tlb,
                                struct vm_area_struct *vma, pmd_t *pmd,
                                unsigned long addr, unsigned long end,
@@ -1679,28 +1700,14 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
        flush_tlb_batched_pending(mm);
        arch_enter_lazy_mmu_mode();
        do {
-               pte_t ptent = ptep_get(pte);
-               int max_nr;
-
-               nr = 1;
-               if (pte_none(ptent))
-                       continue;
-
                if (need_resched())
                        break;
 
-               max_nr = (end - addr) / PAGE_SIZE;
-               if (pte_present(ptent)) {
-                       nr = zap_present_ptes(tlb, vma, pte, ptent, max_nr,
-                                             addr, details, rss, &force_flush,
-                                             &force_break);
-                       if (unlikely(force_break)) {
-                               addr += nr * PAGE_SIZE;
-                               break;
-                       }
-               } else {
-                       nr = zap_nonpresent_ptes(tlb, vma, pte, ptent, max_nr,
-                                                addr, details, rss);
+               nr = do_zap_pte_range(tlb, vma, pte, addr, end, details, rss,
+                                     &force_flush, &force_break);
+               if (unlikely(force_break)) {
+                       addr += nr * PAGE_SIZE;
+                       break;
                }
        } while (pte += nr, addr += PAGE_SIZE * nr, addr != end);