arch_numa: switch over to numa_memblks

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

Adjust a few places in numa_memblks to compile with 32-bit phys_addr_t and
replace current functionality related to numa_add_memblk() and
__node_distance() in arch_numa with the implementation based on
numa_memblks and add functions required by numa_emulation.

[rppt@kernel.org: fix section mismatch]
  Link: https://lkml.kernel.org/r/ZrO6cExVz1He_yPn@kernel.org
[rppt@kernel.org: PFN_PHYS() translation is unnecessary here]
  Link: https://lkml.kernel.org/r/Zs2T5wkSYO9MGcab@kernel.org
Link: https://lkml.kernel.org/r/20240807064110.1003856-25-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Tested-by: Zi Yan <ziy@nvidia.com> # for x86_64 and arm64
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [arm64 + CXL via QEMU]
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Rob Herring (Arm) <robh@kernel.org>
Cc: Samuel Holland <samuel.holland@sifive.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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.

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

include/asm-generic/numa.h

@@ -32,10 +32,8 @@ 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);
+int early_cpu_to_node(int cpu);
 void numa_store_cpu_info(unsigned int cpu);
 void numa_add_cpu(unsigned int cpu);
 void numa_remove_cpu(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 */

mm/numa_memblks.c

@@ -405,9 +405,12 @@ static int __init numa_register_meminfo(struct numa_meminfo *mi)
 		unsigned long pfn_align = node_map_pfn_alignment();
 
 		if (pfn_align && pfn_align < PAGES_PER_SECTION) {
-			pr_warn("Node alignment %LuMB < min %LuMB, rejecting NUMA config\n",
+			unsigned long node_align_mb = PFN_PHYS(pfn_align) >> 20;
-				PFN_PHYS(pfn_align) >> 20,
+
-				PFN_PHYS(PAGES_PER_SECTION) >> 20);
+			unsigned long sect_align_mb = PFN_PHYS(PAGES_PER_SECTION) >> 20;
+
+			pr_warn("Node alignment %luMB < min %luMB, rejecting NUMA config\n",
+				node_align_mb, sect_align_mb);
 			return -EINVAL;
 		}
 	}
@@ -418,18 +421,18 @@ static int __init numa_register_meminfo(struct numa_meminfo *mi)
 int __init numa_memblks_init(int (*init_func)(void),
 			     bool memblock_force_top_down)
 {
+	phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;
 	int ret;
 
 	nodes_clear(numa_nodes_parsed);
 	nodes_clear(node_possible_map);
 	nodes_clear(node_online_map);
 	memset(&numa_meminfo, 0, sizeof(numa_meminfo));
-	WARN_ON(memblock_set_node(0, ULLONG_MAX, &memblock.memory,
+	WARN_ON(memblock_set_node(0, max_addr, &memblock.memory, NUMA_NO_NODE));
-				  NUMA_NO_NODE));
+	WARN_ON(memblock_set_node(0, max_addr, &memblock.reserved,
-	WARN_ON(memblock_set_node(0, ULLONG_MAX, &memblock.reserved,
 				  NUMA_NO_NODE));
 	/* In case that parsing SRAT failed. */
-	WARN_ON(memblock_clear_hotplug(0, ULLONG_MAX));
+	WARN_ON(memblock_clear_hotplug(0, max_addr));
 	numa_reset_distance();
 
 	ret = init_func();