+ mm-align-larger-anonymous-mappings-on-thp-boundaries.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm: align larger anonymous mappings on THP boundaries
has been added to the -mm mm-unstable branch.  Its filename is
     mm-align-larger-anonymous-mappings-on-thp-boundaries.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-align-larger-anonymous-mappings-on-thp-boundaries.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Rik van Riel <riel@surriel.com>
Subject: mm: align larger anonymous mappings on THP boundaries
Date: Tue, 9 Aug 2022 14:24:57 -0400

Align larger anonymous memory mappings on THP boundaries by going through
thp_get_unmapped_area if THPs are enabled for the current process.

With this patch, larger anonymous mappings are now THP aligned.  When a
malloc library allocates a 2MB or larger arena, that arena can now be
mapped with THPs right from the start, which can result in better TLB hit
rates and execution time.

Link: https://lkml.kernel.org/r/20220809142457.4751229f@imladris.surriel.com
Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mmap.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/mm/mmap.c~mm-align-larger-anonymous-mappings-on-thp-boundaries
+++ a/mm/mmap.c
@@ -2229,6 +2229,9 @@ get_unmapped_area(struct file *file, uns
 		 */
 		pgoff = 0;
 		get_area = shmem_get_unmapped_area;
+	} else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) {
+		/* Ensures that larger anonymous mappings are THP aligned. */
+		get_area = thp_get_unmapped_area;
 	}
 
 	addr = get_area(file, addr, len, pgoff, flags);
_

Patches currently in -mm which might be from riel@surriel.com are

mm-align-larger-anonymous-mappings-on-thp-boundaries.patch