[PATCH v3 24/26] arch_numa: switch over to numa_memblks

Mike Rapoport
2024-08-01T06:13:27Z

From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>

Until now arch_numa was directly translating firmware NUMA information
to memblock.

Using numa_memblks as an intermediate step has a few advantages:
* alignment with more battle tested x86 implementation
* availability of NUMA emulation
* maintaining node information for not yet populated memory

Replace current functionality related to numa_add_memblk() and
__node_distance() with the implementation based on numa_memblks and add
functions required by numa_emulation.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Tested-by: Zi Yan <ziy@nvidia.com> # for x86_64 and arm64
---
drivers/base/Kconfig | 1 +
drivers/base/arch_numa.c | 201 +++++++++++--------------------------
include/asm-generic/numa.h | 6 +-
3 files changed, 65 insertions(+), 143 deletions(-)

diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index 2b8fd6bb7da0..064eb52ff7e2 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -226,6 +226,7 @@ config GENERIC_ARCH_TOPOLOGY

config GENERIC_ARCH_NUMA
bool
+ select NUMA_MEMBLKS
help
Enable support for generic NUMA implementation. Currently, RISC-V
and ARM64 use it.
diff --git a/drivers/base/arch_numa.c b/drivers/base/arch_numa.c
index b6af7475ec44..8d49893c0e94 100644
--- a/drivers/base/arch_numa.c
+++ b/drivers/base/arch_numa.c
@@ -12,14 +12,12 @@
#include <linux/memblock.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/numa_memblks.h>

#include <asm/sections.h>

-nodemask_t numa_nodes_parsed __initdata;
static int cpu_to_node_map[NR_CPUS] = { [0 ... NR_CPUS-1] = NUMA_NO_NODE };

-static int numa_distance_cnt;
-static u8 *numa_distance;
bool numa_off;

static __init int numa_parse_early_param(char *opt)
@@ -28,6 +26,8 @@ static __init int numa_parse_early_param(char *opt)
return -EINVAL;
if (str_has_prefix(opt, "off"))
numa_off = true;
+ if (!strncmp(opt, "fake=", 5))
+ return numa_emu_cmdline(opt + 5);

return 0;
}
@@ -59,6 +59,7 @@ EXPORT_SYMBOL(cpumask_of_node);

#endif

+#ifndef CONFIG_NUMA_EMU
static void numa_update_cpu(unsigned int cpu, bool remove)
{
int nid = cpu_to_node(cpu);
@@ -81,6 +82,7 @@ void numa_remove_cpu(unsigned int cpu)
{
numa_update_cpu(cpu, true);
}
+#endif

void numa_clear_node(unsigned int cpu)
{
@@ -142,7 +144,7 @@ void __init early_map_cpu_to_node(unsigned int cpu, int nid)
unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
EXPORT_SYMBOL(__per_cpu_offset);

-int __init early_cpu_to_node(int cpu)
+int early_cpu_to_node(int cpu)
{
return cpu_to_node_map[cpu];
}
@@ -187,30 +189,6 @@ void __init setup_per_cpu_areas(void)
}
#endif

-/**
- * numa_add_memblk() - Set node id to memblk
- * @nid: NUMA node ID of the new memblk
- * @start: Start address of the new memblk
- * @end: End address of the new memblk
- *
- * RETURNS:
- * 0 on success, -errno on failure.
- */
-int __init numa_add_memblk(int nid, u64 start, u64 end)
-{
- int ret;
-
- ret = memblock_set_node(start, (end - start), &memblock.memory, nid);
- if (ret < 0) {
- pr_err("memblock [0x%llx - 0x%llx] failed to add on node %d\n",
- start, (end - 1), nid);
- return ret;
- }
-
- node_set(nid, numa_nodes_parsed);
- return ret;
-}
-
/*
* Initialize NODE_DATA for a node on the local memory
*/
@@ -226,116 +204,9 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
}

-/*
- * numa_free_distance
- *
- * The current table is freed.
- */
-void __init numa_free_distance(void)
-{
- size_t size;
-
- if (!numa_distance)
- return;
-
- size = numa_distance_cnt * numa_distance_cnt *
- sizeof(numa_distance[0]);
-
- memblock_free(numa_distance, size);
- numa_distance_cnt = 0;
- numa_distance = NULL;
-}
-
-/*
- * Create a new NUMA distance table.
- */
-static int __init numa_alloc_distance(void)
-{
- size_t size;
- int i, j;
-
- size = nr_node_ids * nr_node_ids * sizeof(numa_distance[0]);
- numa_distance = memblock_alloc(size, PAGE_SIZE);
- if (WARN_ON(!numa_distance))
- return -ENOMEM;
-
- numa_distance_cnt = nr_node_ids;
-
- /* fill with the default distances */
- for (i = 0; i < numa_distance_cnt; i++)
- for (j = 0; j < numa_distance_cnt; j++)
- numa_distance[i * numa_distance_cnt + j] = i == j ?
- LOCAL_DISTANCE : REMOTE_DISTANCE;
-
- pr_debug("Initialized distance table, cnt=%d\n", numa_distance_cnt);
-
- return 0;
-}
-
-/**
- * numa_set_distance() - Set inter node NUMA distance from node to node.
- * @from: the 'from' node to set distance
- * @to: the 'to' node to set distance
- * @distance: NUMA distance
- *
- * Set the distance from node @from to @to to @distance.
- * If distance table doesn't exist, a warning is printed.
- *
- * If @from or @to is higher than the highest known node or lower than zero
- * or @distance doesn't make sense, the call is ignored.
- */
-void __init numa_set_distance(int from, int to, int distance)
-{
- if (!numa_distance) {
- pr_warn_once("Warning: distance table not allocated yet\n");
- return;
- }
-
- if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
- from < 0 || to < 0) {
- pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
- from, to, distance);
- return;
- }
-
- if ((u8)distance != distance ||
- (from == to && distance != LOCAL_DISTANCE)) {
- pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
- from, to, distance);
- return;
- }
-
- numa_distance[from * numa_distance_cnt + to] = distance;
-}
-
-/*
- * Return NUMA distance @from to @to
- */
-int __node_distance(int from, int to)
-{
- if (from >= numa_distance_cnt || to >= numa_distance_cnt)
- return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
- return numa_distance[from * numa_distance_cnt + to];
-}
-EXPORT_SYMBOL(__node_distance);
-
static int __init numa_register_nodes(void)
{
int nid;
- struct memblock_region *mblk;
-
- /* Check that valid nid is set to memblks */
- for_each_mem_region(mblk) {
- int mblk_nid = memblock_get_region_node(mblk);
- phys_addr_t start = mblk->base;
- phys_addr_t end = mblk->base + mblk->size - 1;
-
- if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) {
- pr_warn("Warning: invalid memblk node %d [mem %pap-%pap]\n",
- mblk_nid, &start, &end);
- return -EINVAL;
- }
- }

/* Finally register nodes. */
for_each_node_mask(nid, numa_nodes_parsed) {
@@ -360,11 +231,7 @@ static int __init numa_init(int (*init_func)(void))
nodes_clear(node_possible_map);
nodes_clear(node_online_map);

- ret = numa_alloc_distance();
- if (ret < 0)
- return ret;
-
- ret = init_func();
+ ret = numa_memblks_init(init_func, /* memblock_force_top_down */ false);
if (ret < 0)
goto out_free_distance;

@@ -382,7 +249,7 @@ static int __init numa_init(int (*init_func)(void))

return 0;
out_free_distance:
- numa_free_distance();
+ numa_reset_distance();
return ret;
}

@@ -412,6 +279,7 @@ static int __init dummy_numa_init(void)
pr_err("NUMA init failed\n");
return ret;
}
+ node_set(0, numa_nodes_parsed);

numa_off = true;
return 0;
@@ -454,3 +322,54 @@ void __init arch_numa_init(void)

numa_init(dummy_numa_init);
}
+
+#ifdef CONFIG_NUMA_EMU
+void __init numa_emu_update_cpu_to_node(int *emu_nid_to_phys,
+ unsigned int nr_emu_nids)
+{
+ int i, j;
+
+ /*
+ * Transform cpu_to_node_map table to use emulated nids by
+ * reverse-mapping phys_nid. The maps should always exist but fall
+ * back to zero just in case.
+ */
+ for (i = 0; i < ARRAY_SIZE(cpu_to_node_map); i++) {
+ if (cpu_to_node_map[i] == NUMA_NO_NODE)
+ continue;
+ for (j = 0; j < nr_emu_nids; j++)
+ if (cpu_to_node_map[i] == emu_nid_to_phys[j])
+ break;
+ cpu_to_node_map[i] = j < nr_emu_nids ? j : 0;
+ }
+}
+
+u64 __init numa_emu_dma_end(void)
+{
+ return PFN_PHYS(memblock_start_of_DRAM() + SZ_4G);
+}
+
+void debug_cpumask_set_cpu(unsigned int cpu, int node, bool enable)
+{
+ struct cpumask *mask;
+
+ if (node == NUMA_NO_NODE)
+ return;
+
+ mask = node_to_cpumask_map[node];
+ if (!cpumask_available(mask)) {
+ pr_err("node_to_cpumask_map[%i] NULL\n", node);
+ dump_stack();
+ return;
+ }
+
+ if (enable)
+ cpumask_set_cpu(cpu, mask);
+ else
+ cpumask_clear_cpu(cpu, mask);
+
+ pr_debug("%s cpu %d node %d: mask now %*pbl\n",
+ enable ? "numa_add_cpu" : "numa_remove_cpu",
+ cpu, node, cpumask_pr_args(mask));
+}
+#endif /* CONFIG_NUMA_EMU */
diff --git a/include/asm-generic/numa.h b/include/asm-generic/numa.h
index c32e0cf23c90..c2b046d1fd82 100644
--- a/include/asm-generic/numa.h
+++ b/include/asm-generic/numa.h
@@ -32,8 +32,6 @@ static inline const struct cpumask *cpumask_of_node(int node)

void __init arch_numa_init(void);
int __init numa_add_memblk(int nodeid, u64 start, u64 end);
-void __init numa_set_distance(int from, int to, int distance);
-void __init numa_free_distance(void);
void __init early_map_cpu_to_node(unsigned int cpu, int nid);
int __init early_cpu_to_node(int cpu);
void numa_store_cpu_info(unsigned int cpu);
@@ -51,4 +49,8 @@ static inline int early_cpu_to_node(int cpu) { return 0; }

#endif /* CONFIG_NUMA */

+#ifdef CONFIG_NUMA_EMU
+void debug_cpumask_set_cpu(unsigned int cpu, int node, bool enable);
+#endif
+
#endif /* __ASM_GENERIC_NUMA_H */
--
2.43.0