mirror of https://gitee.com/openkylin/linux.git
a7ee539584
Currently on PPC64 changing kernel pagesize from 4K to 64K leaves FORCE_MAX_ZONEORDER set to 13 - which produces a compile error. The error occurs because of the following constraint (from include/linux/mmzone.h) being violated: MAX_ORDER -1 + PAGESHIFT <= SECTION_SIZE_BITS. Expanding this out, we get: FORCE_MAX_ZONEBITS <= 25 - PAGESHIFT, which requires, for a 64K page, FORCE_MAX_ZONEBITS <= 9. Thus set max value of FORCE_MAX_ZONEORDER for 64K pages to 9, and 4K pages to 13. Also, check the minimum value: In include/linux/huge_mm.h, we have the constraint HPAGE_PMD_ORDER < MAX_ORDER which expands out to: PTE_INDEX_SIZE < FORCE_MAX_ZONEORDER. PTE_INDEX_SIZE is: 9 (4k hash or no hash 4K pgtable) or 8 (64K hash or no hash 64K pgtable). Thus a min value of 8 for 64K pages and 9 for 4K pages is reasonable. So, update the range of FORCE_MAX_ZONEORDER from 9-64 to 8-9 for 64K pages and from 13-64 to 9-13 for 4K pages. Signed-off-by: Rashmica Gupta <rashmicy@gmail.com> Reviewed-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> |
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| net | ||
| oprofile | ||
| perf | ||
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| relocs_check.sh | ||