Re: [PATCH v4 5/5] riscv: Add numa support for riscv64 platform

From: Anup Patel
Date: Thu Oct 22 2020 - 01:40:50 EST

On Tue, Oct 6, 2020 at 5:48 AM Atish Patra <atish.patra@xxxxxxx> wrote:
>
> Use the generic numa implementation to add NUMA support for RISC-V.
> This is based on Greentime's patch[1] but modified to use generic NUMA
> implementation and few more fixes.
>
> [1] https://lkml.org/lkml/2020/1/10/233
>
> Co-developed-by: Greentime Hu <greentime.hu@xxxxxxxxxx>
> Signed-off-by: Greentime Hu <greentime.hu@xxxxxxxxxx>
> Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
> ---
> arch/riscv/Kconfig | 31 ++++++++++++++++++++++++++++++-
> arch/riscv/include/asm/mmzone.h | 13 +++++++++++++
> arch/riscv/include/asm/numa.h | 8 ++++++++
> arch/riscv/include/asm/pci.h | 14 ++++++++++++++
> arch/riscv/kernel/setup.c | 10 ++++++++--
> arch/riscv/kernel/smpboot.c | 12 +++++++++++-
> arch/riscv/mm/init.c | 4 +++-
> 7 files changed, 87 insertions(+), 5 deletions(-)
> create mode 100644 arch/riscv/include/asm/mmzone.h
> create mode 100644 arch/riscv/include/asm/numa.h
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index df18372861d8..7beb6ddb6eb1 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -137,7 +137,7 @@ config PAGE_OFFSET
> default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
>
> config ARCH_FLATMEM_ENABLE
> - def_bool y
> + def_bool !NUMA
>
> config ARCH_SPARSEMEM_ENABLE
> def_bool y
> @@ -295,6 +295,35 @@ config TUNE_GENERIC
>
> endchoice
>
> +# Common NUMA Features
> +config NUMA
> + bool "NUMA Memory Allocation and Scheduler Support"
> + select GENERIC_ARCH_NUMA
> + select OF_NUMA
> + select ARCH_SUPPORTS_NUMA_BALANCING
> + help
> + Enable NUMA (Non-Uniform Memory Access) support.
> +
> + The kernel will try to allocate memory used by a CPU on the
> + local memory of the CPU and add some more NUMA awareness to the kernel.
> +
> +config NODES_SHIFT
> + int "Maximum NUMA Nodes (as a power of 2)"
> + range 1 10
> + default "2"
> + depends on NEED_MULTIPLE_NODES
> + help
> + Specify the maximum number of NUMA Nodes available on the target
> + system. Increases memory reserved to accommodate various tables.
> +
> +config USE_PERCPU_NUMA_NODE_ID
> + def_bool y
> + depends on NUMA
> +
> +config NEED_PER_CPU_EMBED_FIRST_CHUNK
> + def_bool y
> + depends on NUMA
> +
> config RISCV_ISA_C
> bool "Emit compressed instructions when building Linux"
> default y
> diff --git a/arch/riscv/include/asm/mmzone.h b/arch/riscv/include/asm/mmzone.h
> new file mode 100644
> index 000000000000..fa17e01d9ab2
> --- /dev/null
> +++ b/arch/riscv/include/asm/mmzone.h
> @@ -0,0 +1,13 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef __ASM_MMZONE_H
> +#define __ASM_MMZONE_H
> +
> +#ifdef CONFIG_NUMA
> +
> +#include <asm/numa.h>
> +
> +extern struct pglist_data *node_data[];
> +#define NODE_DATA(nid) (node_data[(nid)])
> +
> +#endif /* CONFIG_NUMA */
> +#endif /* __ASM_MMZONE_H */
> diff --git a/arch/riscv/include/asm/numa.h b/arch/riscv/include/asm/numa.h
> new file mode 100644
> index 000000000000..8c8cf4297cc3
> --- /dev/null
> +++ b/arch/riscv/include/asm/numa.h
> @@ -0,0 +1,8 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef __ASM_NUMA_H
> +#define __ASM_NUMA_H
> +
> +#include <asm/topology.h>
> +#include <asm-generic/numa.h>
> +
> +#endif /* __ASM_NUMA_H */
> diff --git a/arch/riscv/include/asm/pci.h b/arch/riscv/include/asm/pci.h
> index 1c473a1bd986..658e112c3ce7 100644
> --- a/arch/riscv/include/asm/pci.h
> +++ b/arch/riscv/include/asm/pci.h
> @@ -32,6 +32,20 @@ static inline int pci_proc_domain(struct pci_bus *bus)
> /* always show the domain in /proc */
> return 1;
> }
> +
> +#ifdef CONFIG_NUMA
> +
> +static inline int pcibus_to_node(struct pci_bus *bus)
> +{
> + return dev_to_node(&bus->dev);
> +}
> +#ifndef cpumask_of_pcibus
> +#define cpumask_of_pcibus(bus) (pcibus_to_node(bus) == -1 ? \
> + cpu_all_mask : \
> + cpumask_of_node(pcibus_to_node(bus)))
> +#endif
> +#endif /* CONFIG_NUMA */
> +
> #endif /* CONFIG_PCI */
>
> #endif /* _ASM_RISCV_PCI_H */
> diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> index 07fa6d13367e..53a806a9cbaf 100644
> --- a/arch/riscv/kernel/setup.c
> +++ b/arch/riscv/kernel/setup.c
> @@ -101,13 +101,19 @@ void __init setup_arch(char **cmdline_p)
>
> static int __init topology_init(void)
> {
> - int i;
> + int i, ret;
> +
> + for_each_online_node(i)
> + register_one_node(i);
>
> for_each_possible_cpu(i) {
> struct cpu *cpu = &per_cpu(cpu_devices, i);
>
> cpu->hotpluggable = cpu_has_hotplug(i);
> - register_cpu(cpu, i);
> + ret = register_cpu(cpu, i);
> + if (unlikely(ret))
> + pr_warn("Warning: %s: register_cpu %d failed (%d)\n",
> + __func__, i, ret);
> }
>
> return 0;
> diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
> index 96167d55ed98..5e276c25646f 100644
> --- a/arch/riscv/kernel/smpboot.c
> +++ b/arch/riscv/kernel/smpboot.c
> @@ -27,6 +27,7 @@
> #include <asm/cpu_ops.h>
> #include <asm/irq.h>
> #include <asm/mmu_context.h>
> +#include <asm/numa.h>
> #include <asm/tlbflush.h>
> #include <asm/sections.h>
> #include <asm/sbi.h>
> @@ -45,13 +46,18 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
> {
> int cpuid;
> int ret;
> + unsigned int curr_cpuid;
> +
> + curr_cpuid = smp_processor_id();
> + numa_store_cpu_info(curr_cpuid);
> + numa_add_cpu(curr_cpuid);
>
> /* This covers non-smp usecase mandated by "nosmp" option */
> if (max_cpus == 0)
> return;
>
> for_each_possible_cpu(cpuid) {
> - if (cpuid == smp_processor_id())
> + if (cpuid == curr_cpuid)
> continue;
> if (cpu_ops[cpuid]->cpu_prepare) {
> ret = cpu_ops[cpuid]->cpu_prepare(cpuid);
> @@ -59,6 +65,7 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
> continue;
> }
> set_cpu_present(cpuid, true);
> + numa_store_cpu_info(cpuid);
> }
> }
>
> @@ -79,6 +86,7 @@ void __init setup_smp(void)
> if (hart == cpuid_to_hartid_map(0)) {
> BUG_ON(found_boot_cpu);
> found_boot_cpu = 1;
> + early_map_cpu_to_node(0, of_node_to_nid(dn));
> continue;
> }
> if (cpuid >= NR_CPUS) {
> @@ -88,6 +96,7 @@ void __init setup_smp(void)
> }
>
> cpuid_to_hartid_map(cpuid) = hart;
> + early_map_cpu_to_node(cpuid, of_node_to_nid(dn));
> cpuid++;
> }
>
> @@ -153,6 +162,7 @@ asmlinkage __visible void smp_callin(void)
> current->active_mm = mm;
>
> notify_cpu_starting(curr_cpuid);
> + numa_add_cpu(curr_cpuid);
> update_siblings_masks(curr_cpuid);
> set_cpu_online(curr_cpuid, 1);
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 114c3966aadb..c4046e11d264 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -20,6 +20,7 @@
> #include <asm/soc.h>
> #include <asm/io.h>
> #include <asm/ptdump.h>
> +#include <asm/numa.h>
>
> #include "../kernel/head.h"
>
> @@ -185,7 +186,6 @@ void __init setup_bootmem(void)
>
> early_init_fdt_scan_reserved_mem();
> memblock_allow_resize();
> - memblock_dump_all();
>
> for_each_memblock(memory, reg) {
> unsigned long start_pfn = memblock_region_memory_base_pfn(reg);
> @@ -570,9 +570,11 @@ void __init paging_init(void)
>
> void __init misc_mem_init(void)
> {
> + arch_numa_init();
> sparse_init();
> zone_sizes_init();
> resource_init();
> + memblock_dump_all();
> }
>
> #ifdef CONFIG_SPARSEMEM_VMEMMAP
> --
> 2.25.1
>

Looks good to me.

Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx>

Regards,
Anup