mainlining shenanigans
b717d6b93b
The number of scanned pages can be lower than the number of isolated pages when isolating mirgratable or free pageblock. The metric is being reported in trace event and also used in vmstat. some example output from trace where it shows nr_taken can be greater than nr_scanned: Produced by kernel v5.19-rc6 kcompactd0-42 [001] ..... 1210.268022: mm_compaction_isolate_migratepages: range=(0x107ae4 ~ 0x107c00) nr_scanned=265 nr_taken=255 [...] kcompactd0-42 [001] ..... 1210.268382: mm_compaction_isolate_freepages: range=(0x215800 ~ 0x215a00) nr_scanned=13 nr_taken=128 kcompactd0-42 [001] ..... 1210.268383: mm_compaction_isolate_freepages: range=(0x215600 ~ 0x215680) nr_scanned=1 nr_taken=128 mm_compaction_isolate_migratepages does not seem to have this behaviour, but for the reason of consistency, nr_scanned should also be taken care of in that side. This behaviour is confusing since currently the count for isolated pages takes account of compound page but not for the case of scanned pages. And given that the number of isolated pages(nr_taken) reported in mm_compaction_isolate_template trace event is on a single-page basis, the ambiguity when reporting the number of scanned pages can be removed by also including compound page count. Link: https://lkml.kernel.org/r/20220711202806.22296-1-william.lam@bytedance.com Signed-off-by: William Lam <william.lam@bytedance.com> Reviewed-by: Punit Agrawal <punit.agrawal@bytedance.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.