Commit 6b9f29b8 authored by Alexandre Ghiti's avatar Alexandre Ghiti Committed by Dennis Zhou
Browse files

riscv: Enable pcpu page first chunk allocator 



As explained in commit 6ea529a2 ("percpu: make embedding first chunk
allocator check vmalloc space size"), the embedding first chunk allocator
needs the vmalloc space to be larger than the maximum distance between
units which are grouped into NUMA nodes.

On a very sparse NUMA configurations and a small vmalloc area (for example,
it is 64GB in sv39), the allocation of dynamic percpu data in the vmalloc
area could fail.

So provide the pcpu page allocator as a fallback in case we fall into
such a sparse configuration (which happened in arm64 as shown by
commit 09cea619 ("arm64: support page mapping percpu first chunk
allocator")).

Signed-off-by: default avatarAlexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: default avatarDennis Zhou <dennis@kernel.org>
parent 7a92fc8b

arch/riscv/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -414,7 +414,9 @@ config NUMA 
	depends on SMP && MMU

	select ARCH_SUPPORTS_NUMA_BALANCING

	select GENERIC_ARCH_NUMA

	select HAVE_SETUP_PER_CPU_AREA

	select NEED_PER_CPU_EMBED_FIRST_CHUNK

	select NEED_PER_CPU_PAGE_FIRST_CHUNK

	select OF_NUMA

	select USE_PERCPU_NUMA_NODE_ID

	help

arch/riscv/mm/kasan_init.c

+8 −0
Original line number Diff line number Diff line
@@ -438,6 +438,14 @@ static void __init kasan_shallow_populate(void *start, void *end) 
	kasan_shallow_populate_pgd(vaddr, vend);

}



#ifdef CONFIG_KASAN_VMALLOC

void __init kasan_populate_early_vm_area_shadow(void *start, unsigned long size)

{

	kasan_populate(kasan_mem_to_shadow(start),

		       kasan_mem_to_shadow(start + size));

}

#endif



static void __init create_tmp_mapping(void)

{

	void *ptr;