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mm-shmem-add-mthp-size-alignment-in-shmem_get_unmapped_area.patch removed from -mm tree

merged mm-stable Andrew Morton 1 participant 1 message Jun 25, 2024

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The quilt patch titled
Subject: mm: shmem: add mTHP size alignment in shmem_get_unmapped_area
has been removed from the -mm tree. Its filename was
mm-shmem-add-mthp-size-alignment-in-shmem_get_unmapped_area.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: Baolin Wang <[email protected]>
Subject: mm: shmem: add mTHP size alignment in shmem_get_unmapped_area
Date: Tue, 11 Jun 2024 18:11:09 +0800

Although the top-level hugepage allocation can be turned off, anonymous shmem can still use mTHP by configuring the sysfs interface located at '/sys/kernel/mm/transparent_hugepage/hugepage-XXkb/shmem_enabled'. Therefore, add alignment for mTHP size to provide a suitable alignment address in shmem_get_unmapped_area().

Link https://lkml.kernel.org/r/0c549b57cf7db07503af692d8546ecfad0fcce52.1718090413.git.baolin.wang@linux.alibaba.com open here
Signed-off-by Baolin Wang <[email protected]>
Tested-by Lance Yang <[email protected]>
Cc Barry Song <[email protected]>
Cc Daniel Gomez <[email protected]>
Cc David Hildenbrand <[email protected]>
Cc "Huang, Ying" <[email protected]>
Cc Hugh Dickins <[email protected]>
Cc Kefeng Wang <[email protected]>
Cc Pankaj Raghav <[email protected]>
Cc Ryan Roberts <[email protected]>
Cc Yang Shi <[email protected]>
Cc Zi Yan <[email protected]>
Signed-off-by Andrew Morton <[email protected]>

---

 mm/shmem.c |   40 +++++++++++++++++++++++++++++++---------
 1 file changed, 31 insertions(+), 9 deletions(-)
mm/shmem.c renamed from mm/shmem.c~mm-shmem-add-mthp-size-alignment-in-shmem_get_unmapped_area +31 -9
@@ -2393,6 +2393,7 @@ unsigned long shmem_get_unmapped_area(st
 	unsigned long inflated_len;
 	unsigned long inflated_addr;
 	unsigned long inflated_offset;
+	unsigned long hpage_size;
 
 	if (len > TASK_SIZE)
 		return -ENOMEM;

@@ -2411,8 +2412,6 @@ unsigned long shmem_get_unmapped_area(st
 
 	if (shmem_huge == SHMEM_HUGE_DENY)
 		return addr;
-	if (len < HPAGE_PMD_SIZE)
-		return addr;
 	if (flags & MAP_FIXED)
 		return addr;
 	/*

@@ -2424,8 +2423,11 @@ unsigned long shmem_get_unmapped_area(st
 	if (uaddr == addr)
 		return addr;
 
+	hpage_size = HPAGE_PMD_SIZE;
 	if (shmem_huge != SHMEM_HUGE_FORCE) {
 		struct super_block *sb;
+		unsigned long __maybe_unused hpage_orders;
+		int order = 0;
 
 		if (file) {
 			VM_BUG_ON(file->f_op != &shmem_file_operations);

@@ -2438,18 +2440,38 @@ unsigned long shmem_get_unmapped_area(st
 			if (IS_ERR(shm_mnt))
 				return addr;
 			sb = shm_mnt->mnt_sb;
+
+			/*
+			 * Find the highest mTHP order used for anonymous shmem to
+			 * provide a suitable alignment address.
+			 */
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+			hpage_orders = READ_ONCE(huge_shmem_orders_always);
+			hpage_orders |= READ_ONCE(huge_shmem_orders_within_size);
+			hpage_orders |= READ_ONCE(huge_shmem_orders_madvise);
+			if (SHMEM_SB(sb)->huge != SHMEM_HUGE_NEVER)
+				hpage_orders |= READ_ONCE(huge_shmem_orders_inherit);
+
+			if (hpage_orders > 0) {
+				order = highest_order(hpage_orders);
+				hpage_size = PAGE_SIZE << order;
+			}
+#endif
 		}
-		if (SHMEM_SB(sb)->huge == SHMEM_HUGE_NEVER)
+		if (SHMEM_SB(sb)->huge == SHMEM_HUGE_NEVER && !order)
 			return addr;
 	}
 
-	offset = (pgoff << PAGE_SHIFT) & (HPAGE_PMD_SIZE-1);
-	if (offset && offset + len < 2 * HPAGE_PMD_SIZE)
+	if (len < hpage_size)
+		return addr;
+
+	offset = (pgoff << PAGE_SHIFT) & (hpage_size - 1);
+	if (offset && offset + len < 2 * hpage_size)
 		return addr;
-	if ((addr & (HPAGE_PMD_SIZE-1)) == offset)
+	if ((addr & (hpage_size - 1)) == offset)
 		return addr;
 
-	inflated_len = len + HPAGE_PMD_SIZE - PAGE_SIZE;
+	inflated_len = len + hpage_size - PAGE_SIZE;
 	if (inflated_len > TASK_SIZE)
 		return addr;
 	if (inflated_len < len)

@@ -2462,10 +2484,10 @@ unsigned long shmem_get_unmapped_area(st
 	if (inflated_addr & ~PAGE_MASK)
 		return addr;
 
-	inflated_offset = inflated_addr & (HPAGE_PMD_SIZE-1);
+	inflated_offset = inflated_addr & (hpage_size - 1);
 	inflated_addr += offset - inflated_offset;
 	if (inflated_offset > offset)
-		inflated_addr += HPAGE_PMD_SIZE;
+		inflated_addr += hpage_size;
 
 	if (inflated_addr > TASK_SIZE - len)
 		return addr;

_

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