linux/arch/arm64/kernel/acpi_numa.c
Gavin Shan 9e26cac5f8 arm64: numa: Don't check node against MAX_NUMNODES
When the NUMA nodes are sorted by checking ACPI SRAT (GICC AFFINITY)
sub-table, it's impossible for acpi_map_pxm_to_node() to return
any value, which is greater than or equal to MAX_NUMNODES. Lets drop
the unnecessary check in acpi_numa_gicc_affinity_init().

No functional change intended.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Link: https://lore.kernel.org/r/20220718064232.3464373-1-gshan@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-19 19:10:28 +01:00

121 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* ACPI 5.1 based NUMA setup for ARM64
* Lots of code was borrowed from arch/x86/mm/srat.c
*
* Copyright 2004 Andi Kleen, SuSE Labs.
* Copyright (C) 2013-2016, Linaro Ltd.
* Author: Hanjun Guo <hanjun.guo@linaro.org>
*
* 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_gicc_pxm(union acpi_subtable_headers *header,
const unsigned long end)
{
struct acpi_srat_gicc_affinity *pa;
int cpu, pxm, node;
if (srat_disabled())
return -EINVAL;
pa = (struct acpi_srat_gicc_affinity *)header;
if (!pa)
return -EINVAL;
if (!(pa->flags & ACPI_SRAT_GICC_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 -> MPIDR 0x%llx -> Node %d\n", pxm,
cpu_logical_map(cpu), node);
return 0;
}
void __init acpi_map_cpus_to_nodes(void)
{
acpi_table_parse_entries(ACPI_SIG_SRAT, sizeof(struct acpi_table_srat),
ACPI_SRAT_TYPE_GICC_AFFINITY,
acpi_parse_gicc_pxm, 0);
}
/* Callback for Proximity Domain -> ACPI processor UID mapping */
void __init acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa)
{
int pxm, node;
if (srat_disabled())
return;
if (pa->header.length < sizeof(struct acpi_srat_gicc_affinity)) {
pr_err("SRAT: Invalid SRAT header length: %d\n",
pa->header.length);
bad_srat();
return;
}
if (!(pa->flags & ACPI_SRAT_GICC_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);
}