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mm-skip-over-all-consecutive-none-ptes-in-do_zap_pte_range.patch removed from -mm tree

merged mm-stable Andrew Morton 1 participant 1 message Jan 14, 2025

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The quilt patch titled
Subject: mm: skip over all consecutive none ptes in do_zap_pte_range()
has been removed from the -mm tree. Its filename was
mm-skip-over-all-consecutive-none-ptes-in-do_zap_pte_range.patch

This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Qi Zheng <[email protected]>
Subject: mm: skip over all consecutive none ptes in do_zap_pte_range()
Date: Wed, 4 Dec 2024 19:09:45 +0800

Skip over all consecutive none ptes in do_zap_pte_range(), which helps optimize away need_resched() + force_break + incremental pte/addr increments etc.

---

 mm/memory.c |   27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)
mm/memory.c renamed from mm/memory.c~mm-skip-over-all-consecutive-none-ptes-in-do_zap_pte_range +20 -7
@@ -1665,17 +1665,30 @@ static inline int do_zap_pte_range(struc
 {
 	pte_t ptent = ptep_get(pte);
 	int max_nr = (end - addr) / PAGE_SIZE;
+	int nr = 0;
 
-	if (pte_none(ptent))
-		return 1;
+	/* Skip all consecutive none ptes */
+	if (pte_none(ptent)) {
+		for (nr = 1; nr < max_nr; nr++) {
+			ptent = ptep_get(pte + nr);
+			if (!pte_none(ptent))
+				break;
+		}
+		max_nr -= nr;
+		if (!max_nr)
+			return nr;
+		pte += nr;
+		addr += nr * PAGE_SIZE;
+	}
 
 	if (pte_present(ptent))
-		return zap_present_ptes(tlb, vma, pte, ptent, max_nr,
-					addr, details, rss, force_flush,
-					force_break);
+		nr += zap_present_ptes(tlb, vma, pte, ptent, max_nr, addr,
+				       details, rss, force_flush, force_break);
+	else
+		nr += zap_nonpresent_ptes(tlb, vma, pte, ptent, max_nr, addr,
+					  details, rss);
 
-	return zap_nonpresent_ptes(tlb, vma, pte, ptent, max_nr, addr,
-					 details, rss);
+	return nr;
 }
 
 static unsigned long zap_pte_range(struct mmu_gather *tlb,

_

Patches currently in -mm which might be from [email protected] are