diff options
| author | Sudarshan Rajagopalan <sudaraja@codeaurora.org> | 2020-10-14 17:51:23 -0700 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-11-17 18:21:01 +0000 |
| commit | 9f84f39f5515fd412398a1019e3f50ac3ab51a80 (patch) | |
| tree | a9aeecf9aa199e04f8729817aaff6e7a07fe9faf /arch/arm64/mm | |
| parent | 0edaee42eb8c0f3b767ec3c51bee4a3855aa2555 (diff) | |
arm64/mm: add fallback option to allocate virtually contiguous memory
When section mappings are enabled, we allocate vmemmap pages from
physically continuous memory of size PMD_SIZE using
vmemmap_alloc_block_buf(). Section mappings are good to reduce TLB
pressure. But when system is highly fragmented and memory blocks are
being hot-added at runtime, its possible that such physically continuous
memory allocations can fail. Rather than failing the memory hot-add
procedure, add a fallback option to allocate vmemmap pages from
discontinuous pages using vmemmap_populate_basepages().
Signed-off-by: Sudarshan Rajagopalan <sudaraja@codeaurora.org>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/d6c06f2ef39bbe6c715b2f6db76eb16155fdcee6.1602722808.git.sudaraja@codeaurora.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/mm')
| -rw-r--r-- | arch/arm64/mm/mmu.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 1c0f3e02f731..a773d2a1a2bf 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -1132,8 +1132,11 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, void *p = NULL; p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap); - if (!p) - return -ENOMEM; + if (!p) { + if (vmemmap_populate_basepages(addr, next, node, altmap)) + return -ENOMEM; + continue; + } pmd_set_huge(pmdp, __pa(p), __pgprot(PROT_SECT_NORMAL)); } else |