diff options
| author | Anshuman Khandual | 2020-07-01 10:12:01 +0530 |
|---|---|---|
| committer | Catalin Marinas | 2020-07-15 13:38:03 +0100 |
| commit | abb7962adc80ab4f4313e8a065302525b6a9c2dc (patch) | |
| tree | 0fb04418c6b234ba515c8b38abdd2c4080ae4d48 /arch/arm64/mm | |
| parent | 0de674afe83cb23676ec391470251aaa9700f21a (diff) | |
arm64/hugetlb: Reserve CMA areas for gigantic pages on 16K and 64K configs
Currently 'hugetlb_cma=' command line argument does not create CMA area on
ARM64_16K_PAGES and ARM64_64K_PAGES based platforms. Instead, it just ends
up with the following warning message. Reason being, hugetlb_cma_reserve()
never gets called for these huge page sizes.
[ 64.255669] hugetlb_cma: the option isn't supported by current arch
This enables CMA areas reservation on ARM64_16K_PAGES and ARM64_64K_PAGES
configs by defining an unified arm64_hugetlb_cma_reseve() that is wrapped
in CONFIG_CMA. Call site for arm64_hugetlb_cma_reserve() is also protected
as <asm/hugetlb.h> is conditionally included and hence cannot contain stub
for the inverse config i.e !(CONFIG_HUGETLB_PAGE && CONFIG_CMA).
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Barry Song <song.bao.hua@hisilicon.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1593578521-24672-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/mm')
| -rw-r--r-- | arch/arm64/mm/hugetlbpage.c | 38 | ||||
| -rw-r--r-- | arch/arm64/mm/init.c | 4 |
2 files changed, 40 insertions, 2 deletions
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index c79084739096..aa421bf4956e 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -19,6 +19,44 @@ #include <asm/tlbflush.h> #include <asm/pgalloc.h> +/* + * HugeTLB Support Matrix + * + * --------------------------------------------------- + * | Page Size | CONT PTE | PMD | CONT PMD | PUD | + * --------------------------------------------------- + * | 4K | 64K | 2M | 32M | 1G | + * | 16K | 2M | 32M | 1G | | + * | 64K | 2M | 512M | 16G | | + * --------------------------------------------------- + */ + +/* + * Reserve CMA areas for the largest supported gigantic + * huge page when requested. Any other smaller gigantic + * huge pages could still be served from those areas. + */ +#ifdef CONFIG_CMA +void __init arm64_hugetlb_cma_reserve(void) +{ + int order; + +#ifdef CONFIG_ARM64_4K_PAGES + order = PUD_SHIFT - PAGE_SHIFT; +#else + order = CONT_PMD_SHIFT + PMD_SHIFT - PAGE_SHIFT; +#endif + /* + * HugeTLB CMA reservation is required for gigantic + * huge pages which could not be allocated via the + * page allocator. Just warn if there is any change + * breaking this assumption. + */ + WARN_ON(order <= MAX_ORDER); + hugetlb_cma_reserve(order); +} +#endif /* CONFIG_CMA */ + #ifdef CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION bool arch_hugetlb_migration_supported(struct hstate *h) { diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 6c3eb424c613..f8c19c6c8e71 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -425,8 +425,8 @@ void __init bootmem_init(void) * initialize node_online_map that gets used in hugetlb_cma_reserve() * while allocating required CMA size across online nodes. */ -#ifdef CONFIG_ARM64_4K_PAGES - hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT); +#if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_CMA) + arm64_hugetlb_cma_reserve(); #endif /* |