mm: numa_memblks: introduce numa_memblks_init

Move most of x86::numa_init() to numa_memblks so that the latter will be
more self-contained.

With this numa_memblk data structures should not be exposed to the
architecture specific code.

Link: https://lkml.kernel.org/r/20240807064110.1003856-21-rppt@kernel.orgSigned-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>

arch/x86/mm/numa.c

@@ -115,13 +115,9 @@ void __init setup_node_to_cpumask_map(void)
 	pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
 }
 
-static int __init numa_register_memblks(struct numa_meminfo *mi)
+static int __init numa_register_nodes(void)
 {
-	int nid, err;
-
-	err = numa_register_meminfo(mi);
-	if (err)
-		return err;
+	int nid;
 
 	if (!memblock_validate_numa_coverage(SZ_1M))
 		return -EINVAL;
@@ -175,39 +171,11 @@ static int __init numa_init(int (*init_func)(void))
 	for (i = 0; i < MAX_LOCAL_APIC; i++)
 		set_apicid_to_node(i, NUMA_NO_NODE);
 
-	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,
-				  NUMA_NO_NODE));
-	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));
-	numa_reset_distance();
-
-	ret = init_func();
+	ret = numa_memblks_init(init_func, /* memblock_force_top_down */ true);
 	if (ret < 0)
 		return ret;
 
-	/*
-	 * We reset memblock back to the top-down direction
-	 * here because if we configured ACPI_NUMA, we have
-	 * parsed SRAT in init_func(). It is ok to have the
-	 * reset here even if we did't configure ACPI_NUMA
-	 * or acpi numa init fails and fallbacks to dummy
-	 * numa init.
-	 */
-	memblock_set_bottom_up(false);
-
-	ret = numa_cleanup_meminfo(&numa_meminfo);
-	if (ret < 0)
-		return ret;
-
-	numa_emulation(&numa_meminfo, numa_distance_cnt);
-
-	ret = numa_register_memblks(&numa_meminfo);
+	ret = numa_register_nodes();
 	if (ret < 0)
 		return ret;
 

include/linux/numa_memblks.h

@@ -34,6 +34,9 @@ int __init numa_register_meminfo(struct numa_meminfo *mi);
 void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
 				       const struct numa_meminfo *mi);
 
+int __init numa_memblks_init(int (*init_func)(void),
+			     bool memblock_force_top_down);
+
 #ifdef CONFIG_NUMA_EMU
 int numa_emu_cmdline(char *str);
 void __init numa_emu_update_cpu_to_node(int *emu_nid_to_phys,

mm/numa_memblks.c

@@ -415,6 +415,47 @@ int __init numa_register_meminfo(struct numa_meminfo *mi)
 	return 0;
 }
 
+int __init numa_memblks_init(int (*init_func)(void),
+			     bool memblock_force_top_down)
+{
+	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,
+				  NUMA_NO_NODE));
+	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));
+	numa_reset_distance();
+
+	ret = init_func();
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * We reset memblock back to the top-down direction
+	 * here because if we configured ACPI_NUMA, we have
+	 * parsed SRAT in init_func(). It is ok to have the
+	 * reset here even if we did't configure ACPI_NUMA
+	 * or acpi numa init fails and fallbacks to dummy
+	 * numa init.
+	 */
+	if (memblock_force_top_down)
+		memblock_set_bottom_up(false);
+
+	ret = numa_cleanup_meminfo(&numa_meminfo);
+	if (ret < 0)
+		return ret;
+
+	numa_emulation(&numa_meminfo, numa_distance_cnt);
+
+	return numa_register_meminfo(&numa_meminfo);
+}
+
 static int __init cmp_memblk(const void *a, const void *b)
 {
 	const struct numa_memblk *ma = *(const struct numa_memblk **)a;