Re: [PATCH v2 2/6] ACPI: RISCV: Add NUMA support based on SRAT and SLIT

Haibo Xu
2024-04-07T03:09:43Z

On Tue, Apr 2, 2024 at 5:31 PM Alexandre Ghiti <alex@ghiti.fr> wrote:
>
> Hi Haibo,
>
> On 07/03/2024 09:47, Haibo Xu wrote:
> > Add acpi_numa.c file to enable parse NUMA information from
> > ACPI SRAT and SLIT tables. SRAT table provide CPUs(Hart) and
> > memory nodes to proximity domain mapping, while SLIT table
> > provide the distance metrics between proximity domains.
> >
> > Signed-off-by: Haibo Xu <haibo1.xu@intel.com>
> > ---
> > arch/riscv/include/asm/acpi.h | 15 +++-
> > arch/riscv/kernel/Makefile | 1 +
> > arch/riscv/kernel/acpi.c | 5 --
> > arch/riscv/kernel/acpi_numa.c | 131 ++++++++++++++++++++++++++++++++++
> > arch/riscv/kernel/setup.c | 4 +-
> > arch/riscv/kernel/smpboot.c | 2 -
> > include/linux/acpi.h | 6 ++
> > 7 files changed, 154 insertions(+), 10 deletions(-)
> > create mode 100644 arch/riscv/kernel/acpi_numa.c
> >
> > diff --git a/arch/riscv/include/asm/acpi.h b/arch/riscv/include/asm/acpi.h
> > index 7dad0cf9d701..e0a1f84404f3 100644
> > --- a/arch/riscv/include/asm/acpi.h
> > +++ b/arch/riscv/include/asm/acpi.h
> > @@ -61,11 +61,14 @@ static inline void arch_fix_phys_package_id(int num, u32 slot) { }
> >
> > void acpi_init_rintc_map(void);
> > struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu);
> > -u32 get_acpi_id_for_cpu(int cpu);
> > +static inline u32 get_acpi_id_for_cpu(int cpu)
> > +{
> > + return acpi_cpu_get_madt_rintc(cpu)->uid;
> > +}
> > +
> > int acpi_get_riscv_isa(struct acpi_table_header *table,
> > unsigned int cpu, const char **isa);
> >
> > -static inline int acpi_numa_get_nid(unsigned int cpu) { return NUMA_NO_NODE; }
> > void acpi_get_cbo_block_size(struct acpi_table_header *table, u32 *cbom_size,
> > u32 *cboz_size, u32 *cbop_size);
> > #else
> > @@ -87,4 +90,12 @@ static inline void acpi_get_cbo_block_size(struct acpi_table_header *table,
> >
> > #endif /* CONFIG_ACPI */
> >
> > +#ifdef CONFIG_ACPI_NUMA
> > +int acpi_numa_get_nid(unsigned int cpu);
> > +void acpi_map_cpus_to_nodes(void);
> > +#else
> > +static inline int acpi_numa_get_nid(unsigned int cpu) { return NUMA_NO_NODE; }
> > +static inline void acpi_map_cpus_to_nodes(void) { }
> > +#endif /* CONFIG_ACPI_NUMA */
> > +
> > #endif /*_ASM_ACPI_H*/
> > diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
> > index f71910718053..5d3e9cf89b76 100644
> > --- a/arch/riscv/kernel/Makefile
> > +++ b/arch/riscv/kernel/Makefile
> > @@ -105,3 +105,4 @@ obj-$(CONFIG_COMPAT) += compat_vdso/
> >
> > obj-$(CONFIG_64BIT) += pi/
> > obj-$(CONFIG_ACPI) += acpi.o
> > +obj-$(CONFIG_ACPI_NUMA) += acpi_numa.o
> > diff --git a/arch/riscv/kernel/acpi.c b/arch/riscv/kernel/acpi.c
> > index e619edc8b0cc..040bdbfea2b4 100644
> > --- a/arch/riscv/kernel/acpi.c
> > +++ b/arch/riscv/kernel/acpi.c
> > @@ -191,11 +191,6 @@ struct acpi_madt_rintc *acpi_cpu_get_madt_rintc(int cpu)
> > return &cpu_madt_rintc[cpu];
> > }
> >
> > -u32 get_acpi_id_for_cpu(int cpu)
> > -{
> > - return acpi_cpu_get_madt_rintc(cpu)->uid;
> > -}
> > -
> > /*
> > * __acpi_map_table() will be called before paging_init(), so early_ioremap()
> > * or early_memremap() should be called here to for ACPI table mapping.
> > diff --git a/arch/riscv/kernel/acpi_numa.c b/arch/riscv/kernel/acpi_numa.c
> > new file mode 100644
> > index 000000000000..0231482d6946
> > --- /dev/null
> > +++ b/arch/riscv/kernel/acpi_numa.c
> > @@ -0,0 +1,131 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * ACPI 6.6 based NUMA setup for RISCV
> > + * Lots of code was borrowed from arch/arm64/kernel/acpi_numa.c
> > + *
> > + * Copyright 2004 Andi Kleen, SuSE Labs.
> > + * Copyright (C) 2013-2016, Linaro Ltd.
> > + * Author: Hanjun Guo <hanjun.guo@linaro.org>
> > + * Copyright (C) 2024 Intel Corporation.
> > + *
> > + * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
> > + *
> > + * Called from acpi_numa_init while reading the SRAT and SLIT tables.
> > + * Assumes all memory regions belonging to a single proximity domain
> > + * are in one chunk. Holes between them will be included in the node.
> > + */
> > +
> > +#define pr_fmt(fmt) "ACPI: NUMA: " fmt
> > +
> > +#include <linux/acpi.h>
> > +#include <linux/bitmap.h>
> > +#include <linux/kernel.h>
> > +#include <linux/mm.h>
> > +#include <linux/memblock.h>
> > +#include <linux/mmzone.h>
> > +#include <linux/module.h>
> > +#include <linux/topology.h>
> > +
> > +#include <asm/numa.h>
> > +
> > +static int acpi_early_node_map[NR_CPUS] __initdata = { NUMA_NO_NODE };
> > +
> > +int __init acpi_numa_get_nid(unsigned int cpu)
> > +{
> > + return acpi_early_node_map[cpu];
> > +}
> > +
> > +static inline int get_cpu_for_acpi_id(u32 uid)
> > +{
> > + int cpu;
> > +
> > + for (cpu = 0; cpu < nr_cpu_ids; cpu++)
> > + if (uid == get_acpi_id_for_cpu(cpu))
> > + return cpu;
> > +
> > + return -EINVAL;
> > +}
> > +
> > +static int __init acpi_parse_rintc_pxm(union acpi_subtable_headers *header,
> > + const unsigned long end)
> > +{
> > + struct acpi_srat_rintc_affinity *pa;
> > + int cpu, pxm, node;
> > +
> > + if (srat_disabled())
> > + return -EINVAL;
> > +
> > + pa = (struct acpi_srat_rintc_affinity *)header;
> > + if (!pa)
> > + return -EINVAL;
> > +
> > + if (!(pa->flags & ACPI_SRAT_RINTC_ENABLED))
> > + return 0;
> > +
> > + pxm = pa->proximity_domain;
> > + node = pxm_to_node(pxm);
> > +
> > + /*
> > + * If we can't map the UID to a logical cpu this
> > + * means that the UID is not part of possible cpus
> > + * so we do not need a NUMA mapping for it, skip
> > + * the SRAT entry and keep parsing.
> > + */
> > + cpu = get_cpu_for_acpi_id(pa->acpi_processor_uid);
> > + if (cpu < 0)
> > + return 0;
> > +
> > + acpi_early_node_map[cpu] = node;
> > + pr_info("SRAT: PXM %d -> HARTID 0x%lx -> Node %d\n", pxm,
> > + cpuid_to_hartid_map(cpu), node);
> > +
> > + return 0;
> > +}
> > +
> > +void __init acpi_map_cpus_to_nodes(void)
> > +{
> > + int i;
> > +
> > + /*
> > + * In ACPI, SMP and CPU NUMA information is provided in separate
> > + * static tables, namely the MADT and the SRAT.
> > + *
> > + * Thus, it is simpler to first create the cpu logical map through
> > + * an MADT walk and then map the logical cpus to their node ids
> > + * as separate steps.
> > + */
> > + acpi_table_parse_entries(ACPI_SIG_SRAT, sizeof(struct acpi_table_srat),
> > + ACPI_SRAT_TYPE_RINTC_AFFINITY, acpi_parse_rintc_pxm, 0);
> > +
> > + for (i = 0; i < nr_cpu_ids; i++)
> > + early_map_cpu_to_node(i, acpi_numa_get_nid(i));
> > +}
> > +
> > +/* Callback for Proximity Domain -> logical node ID mapping */
> > +void __init acpi_numa_rintc_affinity_init(struct acpi_srat_rintc_affinity *pa)
> > +{
> > + int pxm, node;
> > +
> > + if (srat_disabled())
> > + return;
> > +
> > + if (pa->header.length < sizeof(struct acpi_srat_rintc_affinity)) {
> > + pr_err("SRAT: Invalid SRAT header length: %d\n", pa->header.length);
> > + bad_srat();
> > + return;
> > + }
> > +
> > + if (!(pa->flags & ACPI_SRAT_RINTC_ENABLED))
> > + return;
> > +
> > + pxm = pa->proximity_domain;
> > + node = acpi_map_pxm_to_node(pxm);
> > +
> > + if (node == NUMA_NO_NODE) {
> > + pr_err("SRAT: Too many proximity domains %d\n", pxm);
> > + bad_srat();
> > + return;
> > + }
> > +
> > + node_set(node, numa_nodes_parsed);
> > +}
>
>
> What is riscv specific in the parsing of those tables? Can't we try to
> merge this into generic ACPI code? I know that's a burden to try and
> factorize code with other architectures instead of reusing it, but it
> showed numerous times that duplicating was even worse (I have the NAPOT
> code in mind).
>

Hi Alex,

The acpi_srat_rintc_affinity structure is RISC-V specific and that's
why I put the
callback in arch/riscv/kernel/acpi_numa.c.

Thanks,
Haibo

> Thanks,
>
> Alex
>
>
> > diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
> > index 4f73c0ae44b2..a2cde65b69e9 100644
> > --- a/arch/riscv/kernel/setup.c
> > +++ b/arch/riscv/kernel/setup.c
> > @@ -281,8 +281,10 @@ void __init setup_arch(char **cmdline_p)
> > setup_smp();
> > #endif
> >
> > - if (!acpi_disabled)
> > + if (!acpi_disabled) {
> > acpi_init_rintc_map();
> > + acpi_map_cpus_to_nodes();
> > + }
> >
> > riscv_init_cbo_blocksizes();
> > riscv_fill_hwcap();
> > diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
> > index cfbe4b840d42..81a2aa77680c 100644
> > --- a/arch/riscv/kernel/smpboot.c
> > +++ b/arch/riscv/kernel/smpboot.c
> > @@ -100,7 +100,6 @@ static int __init acpi_parse_rintc(union acpi_subtable_headers *header, const un
> > if (hart == cpuid_to_hartid_map(0)) {
> > BUG_ON(found_boot_cpu);
> > found_boot_cpu = true;
> > - early_map_cpu_to_node(0, acpi_numa_get_nid(cpu_count));
> > return 0;
> > }
> >
> > @@ -110,7 +109,6 @@ static int __init acpi_parse_rintc(union acpi_subtable_headers *header, const un
> > }
> >
> > cpuid_to_hartid_map(cpu_count) = hart;
> > - early_map_cpu_to_node(cpu_count, acpi_numa_get_nid(cpu_count));
> > cpu_count++;
> >
> > return 0;
> > diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> > index b7165e52b3c6..f74c62956e07 100644
> > --- a/include/linux/acpi.h
> > +++ b/include/linux/acpi.h
> > @@ -269,6 +269,12 @@ acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa) { }
> >
> > int acpi_numa_memory_affinity_init (struct acpi_srat_mem_affinity *ma);
> >
> > +#ifdef CONFIG_RISCV
> > +void acpi_numa_rintc_affinity_init(struct acpi_srat_rintc_affinity *pa);
> > +#else
> > +static inline void acpi_numa_rintc_affinity_init(struct acpi_srat_rintc_affinity *pa) { }
> > +#endif
> > +
> > #ifndef PHYS_CPUID_INVALID
> > typedef u32 phys_cpuid_t;
> > #define PHYS_CPUID_INVALID (phys_cpuid_t)(-1)