| Message ID | 20241209094227.1529977-1-quic_zhenhuah@quicinc.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Fix subsection vmemmap_populate logic | expand |
On 2024/12/9 17:42, Zhenhua Huang wrote: > To perform memory hotplug operations, the memmap (aka struct page) will be > updated. For arm64 with 4K page size, the typical granularity is 128M, > which corresponds to a 2M memmap buffer. > Commit c1cc1552616d ("arm64: MMU initialisation") > optimizes this 2M buffer to be mapped with one single PMD entry. However, > commit ba72b4c8cf60 ("mm/sparsemem: support sub-section hotplug") > which supports 2M subsection hotplug granularity, causes other issues > (refer to the change log of patch #1). The logic is adjusted to populate > with huge pages only if the hotplug address/size is section-aligned. > Could any expert help review please? > Changes since v1: > - Modified change log to make it more clear which was based on Catalin's > comments. > > Zhenhua Huang (2): > arm64: mm: vmemmap populate to page level if not section aligned > arm64: mm: implement vmemmap_check_pmd for arm64 > > arch/arm64/mm/mmu.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) >
To perform memory hotplug operations, the memmap (aka struct page) will be updated. For arm64 with 4K page size, the typical granularity is 128M, which corresponds to a 2M memmap buffer. Commit c1cc1552616d ("arm64: MMU initialisation") optimizes this 2M buffer to be mapped with one single PMD entry. However, commit ba72b4c8cf60 ("mm/sparsemem: support sub-section hotplug") which supports 2M subsection hotplug granularity, causes other issues (refer to the change log of patch #1). The logic is adjusted to populate with huge pages only if the hotplug address/size is section-aligned. Changes since v1: - Modified change log to make it more clear which was based on Catalin's comments. Zhenhua Huang (2): arm64: mm: vmemmap populate to page level if not section aligned arm64: mm: implement vmemmap_check_pmd for arm64 arch/arm64/mm/mmu.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)