| Message ID | 20181015175702.9036-7-logang@deltatee.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | sparsemem support for RISC-V | expand |
Hello Logan, Στις 2018-10-15 20:57, Logan Gunthorpe έγραψε: > This patch implements sparsemem support for risc-v which helps pave the > way for memory hotplug and eventually P2P support. > > We introduce Kconfig options for virtual and physical address bits > which > are used to calculate the size of the vmemmap and set the > MAX_PHYSMEM_BITS. > > The vmemmap is located directly before the VMALLOC region and sized > such that we can allocate enough pages to populate all the virtual > address space in the system (similar to the way it's done in arm64). > > During initialization, call memblocks_present() and sparse_init(), > and provide a stub for vmemmap_populate() (all of which is similar to > arm64). > > Signed-off-by: Logan Gunthorpe <logang@deltatee.com> > Reviewed-by: Palmer Dabbelt <palmer@sifive.com> > Cc: Albert Ou <aou@eecs.berkeley.edu> > Cc: Andrew Waterman <andrew@sifive.com> > Cc: Olof Johansson <olof@lixom.net> > Cc: Michael Clark <michaeljclark@mac.com> > Cc: Rob Herring <robh@kernel.org> > Cc: Zong Li <zong@andestech.com> > --- > arch/riscv/Kconfig | 23 +++++++++++++++++++++++ > arch/riscv/include/asm/pgtable.h | 21 +++++++++++++++++---- > arch/riscv/include/asm/sparsemem.h | 11 +++++++++++ > arch/riscv/kernel/setup.c | 4 +++- > arch/riscv/mm/init.c | 8 ++++++++ > 5 files changed, 62 insertions(+), 5 deletions(-) > create mode 100644 arch/riscv/include/asm/sparsemem.h > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index a344980287a5..a1b5d758a542 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -52,12 +52,32 @@ config ZONE_DMA32 > bool > default y if 64BIT > > +config VA_BITS > + int > + default 32 if 32BIT > + default 39 if 64BIT > + > +config PA_BITS > + int > + default 34 if 32BIT > + default 56 if 64BIT > + > config PAGE_OFFSET > hex > default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB > default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB > default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB > > +config ARCH_FLATMEM_ENABLE > + def_bool y > + > +config ARCH_SPARSEMEM_ENABLE > + def_bool y > + select SPARSEMEM_VMEMMAP_ENABLE > + > +config ARCH_SELECT_MEMORY_MODEL > + def_bool ARCH_SPARSEMEM_ENABLE > + > config STACKTRACE_SUPPORT > def_bool y > > @@ -92,6 +112,9 @@ config PGTABLE_LEVELS > config HAVE_KPROBES > def_bool n > > +config HAVE_ARCH_PFN_VALID > + def_bool y > + > menu "Platform type" > > choice > diff --git a/arch/riscv/include/asm/pgtable.h > b/arch/riscv/include/asm/pgtable.h > index 16301966d65b..e1162336f5ea 100644 > --- a/arch/riscv/include/asm/pgtable.h > +++ b/arch/riscv/include/asm/pgtable.h > @@ -89,6 +89,23 @@ extern pgd_t swapper_pg_dir[]; > #define __S110 PAGE_SHARED_EXEC > #define __S111 PAGE_SHARED_EXEC > > +#define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1) > +#define VMALLOC_END (PAGE_OFFSET - 1) > +#define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE) > + > +/* > + * Roughly size the vmemmap space to be large enough to fit enough > + * struct pages to map half the virtual address space. Then > + * position vmemmap directly below the VMALLOC region. > + */ > +#define VMEMMAP_SHIFT \ > + (CONFIG_VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT) > +#define VMEMMAP_SIZE (1UL << VMEMMAP_SHIFT) > +#define VMEMMAP_END (VMALLOC_START - 1) > +#define VMEMMAP_START (VMALLOC_START - VMEMMAP_SIZE) > + > +#define vmemmap ((struct page *)VMEMMAP_START) > + > /* > * ZERO_PAGE is a global shared page that is always zero, > * used for zero-mapped memory areas, etc. > @@ -411,10 +428,6 @@ static inline void pgtable_cache_init(void) > /* No page table caches to initialize */ > } > > -#define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1) > -#define VMALLOC_END (PAGE_OFFSET - 1) > -#define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE) > - > /* > * Task size is 0x40000000000 for RV64 or 0xb800000 for RV32. > * Note that PGDIR_SIZE must evenly divide TASK_SIZE. > diff --git a/arch/riscv/include/asm/sparsemem.h > b/arch/riscv/include/asm/sparsemem.h > new file mode 100644 > index 000000000000..215530b24336 > --- /dev/null > +++ b/arch/riscv/include/asm/sparsemem.h > @@ -0,0 +1,11 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > + > +#ifndef __ASM_SPARSEMEM_H > +#define __ASM_SPARSEMEM_H > + > +#ifdef CONFIG_SPARSEMEM > +#define MAX_PHYSMEM_BITS CONFIG_PA_BITS > +#define SECTION_SIZE_BITS 30 Having memory blocks of a minimum size of 1GB doesn't make much sense. It makes it harder to implement hotplug on top of this since we'll only able to add/remove 1GB at a time. ARM used to do the same and they switched to 27bits (https://patchwork.kernel.org/patch/9172845/), ARM64 still uses 1GB, x86 also uses 27bits and most archs also use something below 30. I believe we should go for 27bits as well or even better have this as a compile time option. BTW memblocks_present is on master now (got merged 3 days ago). Regards, N.
On 2018-12-17 7:59 a.m., Nick Kossifidis wrote: > Having memory blocks of a minimum size of 1GB doesn't make much sense. > It makes it harder to implement hotplug on top of this since we'll only > able to add/remove 1GB at a time. ARM used to do the same and they > switched to 27bits (https://patchwork.kernel.org/patch/9172845/), ARM64 > still uses 1GB, x86 also uses 27bits and most archs also use something > below 30. I believe we should go for 27bits as well or even better have > this as a compile time option. Thanks, that makes sense. I'll make the change for the next time we submit. > BTW memblocks_present is on master now (got merged 3 days ago). Great! We'll send an updated patch set after the merge window. Logan
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index a344980287a5..a1b5d758a542 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -52,12 +52,32 @@ config ZONE_DMA32 bool default y if 64BIT +config VA_BITS + int + default 32 if 32BIT + default 39 if 64BIT + +config PA_BITS + int + default 34 if 32BIT + default 56 if 64BIT + config PAGE_OFFSET hex default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB +config ARCH_FLATMEM_ENABLE + def_bool y + +config ARCH_SPARSEMEM_ENABLE + def_bool y + select SPARSEMEM_VMEMMAP_ENABLE + +config ARCH_SELECT_MEMORY_MODEL + def_bool ARCH_SPARSEMEM_ENABLE + config STACKTRACE_SUPPORT def_bool y @@ -92,6 +112,9 @@ config PGTABLE_LEVELS config HAVE_KPROBES def_bool n +config HAVE_ARCH_PFN_VALID + def_bool y + menu "Platform type" choice diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 16301966d65b..e1162336f5ea 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -89,6 +89,23 @@ extern pgd_t swapper_pg_dir[]; #define __S110 PAGE_SHARED_EXEC #define __S111 PAGE_SHARED_EXEC +#define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1) +#define VMALLOC_END (PAGE_OFFSET - 1) +#define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE) + +/* + * Roughly size the vmemmap space to be large enough to fit enough + * struct pages to map half the virtual address space. Then + * position vmemmap directly below the VMALLOC region. + */ +#define VMEMMAP_SHIFT \ + (CONFIG_VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT) +#define VMEMMAP_SIZE (1UL << VMEMMAP_SHIFT) +#define VMEMMAP_END (VMALLOC_START - 1) +#define VMEMMAP_START (VMALLOC_START - VMEMMAP_SIZE) + +#define vmemmap ((struct page *)VMEMMAP_START) + /* * ZERO_PAGE is a global shared page that is always zero, * used for zero-mapped memory areas, etc. @@ -411,10 +428,6 @@ static inline void pgtable_cache_init(void) /* No page table caches to initialize */ } -#define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1) -#define VMALLOC_END (PAGE_OFFSET - 1) -#define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE) - /* * Task size is 0x40000000000 for RV64 or 0xb800000 for RV32. * Note that PGDIR_SIZE must evenly divide TASK_SIZE. diff --git a/arch/riscv/include/asm/sparsemem.h b/arch/riscv/include/asm/sparsemem.h new file mode 100644 index 000000000000..215530b24336 --- /dev/null +++ b/arch/riscv/include/asm/sparsemem.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __ASM_SPARSEMEM_H +#define __ASM_SPARSEMEM_H + +#ifdef CONFIG_SPARSEMEM +#define MAX_PHYSMEM_BITS CONFIG_PA_BITS +#define SECTION_SIZE_BITS 30 +#endif /* CONFIG_SPARSEMEM */ + +#endif /* __ASM_SPARSEMEM_H */ diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index b2d26d9d8489..494c380e4ea6 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -205,6 +205,9 @@ static void __init setup_bootmem(void) PFN_PHYS(end_pfn - start_pfn), &memblock.memory, 0); } + + memblocks_present(); + sparse_init(); } void __init setup_arch(char **cmdline_p) @@ -239,4 +242,3 @@ void __init setup_arch(char **cmdline_p) riscv_fill_hwcap(); } - diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 58a522f9bcc3..5d529878667c 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -70,3 +70,11 @@ void free_initrd_mem(unsigned long start, unsigned long end) { } #endif /* CONFIG_BLK_DEV_INITRD */ + +#ifdef CONFIG_SPARSEMEM +int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, + struct vmem_altmap *altmap) +{ + return vmemmap_populate_basepages(start, end, node); +} +#endif