+ mm-page_isolation-fixup-isolate_single_pageblock-comment-regarding-splitting-free-pages.patch added to mm-unstable branch

+ mm-page_isolation-fixup-isolate_single_pageblock-comment-regarding-splitting-free-pages.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/page_isolation: fixup isolate_single_pageblock() comment regarding splitting free pages
has been added to the -mm mm-unstable branch.  Its filename is
     mm-page_isolation-fixup-isolate_single_pageblock-comment-regarding-splitting-free-pages.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_isolation-fixup-isolate_single_pageblock-comment-regarding-splitting-free-pages.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: David Hildenbrand <david@redhat.com>
Subject: mm/page_isolation: fixup isolate_single_pageblock() comment regarding splitting free pages
Date: Fri, 6 Dec 2024 10:59:51 +0100

Let's fixup the comment, documenting how free_one_page_maybe_split()
comes into play.

Link: https://lkml.kernel.org/r/20241206095951.98007-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/page_isolation.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

--- a/mm/page_isolation.c~mm-page_isolation-fixup-isolate_single_pageblock-comment-regarding-splitting-free-pages
+++ a/mm/page_isolation.c
@@ -298,11 +298,10 @@ __first_valid_page(unsigned long pfn, un
  * pagelbocks.
  * [      MAX_PAGE_ORDER         ]
  * [  pageblock0  |  pageblock1  ]
- * When either pageblock is isolated, if it is a free page, the page is not
- * split into separate migratetype lists, which is supposed to; if it is an
- * in-use page and freed later, __free_one_page() does not split the free page
- * either. The function handles this by splitting the free page or migrating
- * the in-use page then splitting the free page.
+ * When either pageblock is isolated, if it is an in-use page and freed later,
+ * __free_one_page_maybe_split() will split the free page if required. If the
+ * page is already free, this function handles this by splitting the free page
+ * through move_freepages_block_isolate()->__free_one_page_maybe_split().
  */
 static int isolate_single_pageblock(unsigned long boundary_pfn, int flags,
 		bool isolate_before, bool skip_isolation, int migratetype)
_

Patches currently in -mm which might be from david@redhat.com are

docs-tmpfs-update-the-large-folios-policy-for-tmpfs-and-shmem.patch
mm-memory_hotplug-move-debug_pagealloc_map_pages-into-online_pages_range.patch
mm-page_isolation-dont-pass-gfp-flags-to-isolate_single_pageblock.patch
mm-page_isolation-dont-pass-gfp-flags-to-start_isolate_page_range.patch
mm-page_alloc-make-__alloc_contig_migrate_range-static.patch
mm-page_alloc-sort-out-the-alloc_contig_range-gfp-flags-mess.patch
mm-page_alloc-forward-the-gfp-flags-from-alloc_contig_range-to-post_alloc_hook.patch
powernv-memtrace-use-__gfp_zero-with-alloc_contig_pages.patch
mm-hugetlb-dont-map-folios-writable-without-vm_write-when-copying-during-fork.patch
fs-proc-vmcore-convert-vmcore_cb_lock-into-vmcore_mutex.patch
fs-proc-vmcore-replace-vmcoredd_mutex-by-vmcore_mutex.patch
fs-proc-vmcore-disallow-vmcore-modifications-while-the-vmcore-is-open.patch
fs-proc-vmcore-prefix-all-pr_-with-vmcore.patch
fs-proc-vmcore-move-vmcore-definitions-out-of-kcoreh.patch
fs-proc-vmcore-factor-out-allocating-a-vmcore-range-and-adding-it-to-a-list.patch
fs-proc-vmcore-factor-out-freeing-a-list-of-vmcore-ranges.patch
fs-proc-vmcore-introduce-proc_vmcore_device_ram-to-detect-device-ram-ranges-in-2nd-kernel.patch
virtio-mem-mark-device-ready-before-registering-callbacks-in-kdump-mode.patch
virtio-mem-remember-usable-region-size.patch
virtio-mem-support-config_proc_vmcore_device_ram.patch
s390-kdump-virtio-mem-kdump-support-config_proc_vmcore_device_ram.patch
mm-page_alloc-conditionally-split-pageblock_order-pages-in-free_one_page-and-move_freepages_block_isolate.patch
mm-page_isolation-fixup-isolate_single_pageblock-comment-regarding-splitting-free-pages.patch