Kemeng Shi 7c0a84bd0d mm/compaction: correct last_migrated_pfn update in compact_zone
We record start pfn of last isolated page block with last_migrated_pfn. And
then:

1. We check if we mark the page block skip for exclusive access in
   isolate_migratepages_block by test if next migrate pfn is still in last
   isolated page block.  If so, we will set finish_pageblock to do the
   rescan.

2. We check if a full cc->order block is scanned by test if last scan
   range passes the cc->order block boundary.  If so, we flush the pages
   were freed.

We treat cc->migrate_pfn before isolate_migratepages as the start pfn of
last isolated page range.  However, we always align migrate_pfn to page
block or move to another page block in fast_find_migrateblock or in
linearly scan forward in isolate_migratepages before do page isolation in
isolate_migratepages_block.

Update last_migrated_pfn with pageblock_start_pfn(cc->migrate_pfn - 1)
after scan to correctly set start pfn of last isolated page range. To
avoid that:

1. Miss a rescan with finish_pageblock set as last_migrate_pfn does
   not point to right pageblock and the migrate will not be in pageblock
   of last_migrate_pfn as it should be.

2. Wrongly issue flush by test cc->order block boundary with wrong
   last_migrate_pfn.

Link: https://lkml.kernel.org/r/20230804110454.2935878-3-shikemeng@huaweicloud.com
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 13:37:42 -07:00
2023-08-18 10:12:02 -07:00
2022-09-28 09:02:20 +02:00
2023-08-21 13:37:26 -07:00
2023-07-30 13:23:47 -07:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 7.9 GiB
Languages
C 97.7%
Assembly 1.6%
Makefile 0.3%
Perl 0.1%