[PATCH RFC 1/5] mm/numa: move numa emulation APIs into generic files

From: Rongwei Wang
Date: Wed Oct 11 2023 - 22:49:26 EST


In order to support NUMA EMU for other
arch, some functions that used by numa_meminfo
should be moved out x86 arch. mm/numa.c created
to place above API.

CONFIG_NUMA_EMU will be handled later.

Signed-off-by: Rongwei Wang <rongwei.wang@xxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/numa.h | 3 -
arch/x86/mm/numa.c | 216 +-------------------------
arch/x86/mm/numa_internal.h | 14 +-
include/asm-generic/numa.h | 18 +++
mm/Makefile | 1 +
mm/numa.c | 298 ++++++++++++++++++++++++++++++++++++
6 files changed, 323 insertions(+), 227 deletions(-)
create mode 100644 mm/numa.c

diff --git a/arch/x86/include/asm/numa.h b/arch/x86/include/asm/numa.h
index e3bae2b60a0d..8d79be8095d5 100644
--- a/arch/x86/include/asm/numa.h
+++ b/arch/x86/include/asm/numa.h
@@ -9,9 +9,6 @@
#include <asm/apicdef.h>

#ifdef CONFIG_NUMA
-
-#define NR_NODE_MEMBLKS (MAX_NUMNODES*2)
-
/*
* Too small node sizes may confuse the VM badly. Usually they
* result from BIOS bugs. So dont recognize nodes as standalone
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index 2aadb2019b4f..969b11fff03f 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -25,8 +25,8 @@ nodemask_t numa_nodes_parsed __initdata;
struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
EXPORT_SYMBOL(node_data);

-static struct numa_meminfo numa_meminfo __initdata_or_meminfo;
-static struct numa_meminfo numa_reserved_meminfo __initdata_or_meminfo;
+extern struct numa_meminfo numa_meminfo;
+extern struct numa_meminfo numa_reserved_meminfo;

static int numa_distance_cnt;
static u8 *numa_distance;
@@ -148,34 +148,6 @@ static int __init numa_add_memblk_to(int nid, u64 start, u64 end,
return 0;
}

-/**
- * numa_remove_memblk_from - Remove one numa_memblk from a numa_meminfo
- * @idx: Index of memblk to remove
- * @mi: numa_meminfo to remove memblk from
- *
- * Remove @idx'th numa_memblk from @mi by shifting @mi->blk[] and
- * decrementing @mi->nr_blks.
- */
-void __init numa_remove_memblk_from(int idx, struct numa_meminfo *mi)
-{
- mi->nr_blks--;
- memmove(&mi->blk[idx], &mi->blk[idx + 1],
- (mi->nr_blks - idx) * sizeof(mi->blk[0]));
-}
-
-/**
- * numa_move_tail_memblk - Move a numa_memblk from one numa_meminfo to another
- * @dst: numa_meminfo to append block to
- * @idx: Index of memblk to remove
- * @src: numa_meminfo to remove memblk from
- */
-static void __init numa_move_tail_memblk(struct numa_meminfo *dst, int idx,
- struct numa_meminfo *src)
-{
- dst->blk[dst->nr_blks++] = src->blk[idx];
- numa_remove_memblk_from(idx, src);
-}
-
/**
* numa_add_memblk - Add one numa_memblk to numa_meminfo
* @nid: NUMA node ID of the new memblk
@@ -225,124 +197,6 @@ static void __init alloc_node_data(int nid)
node_set_online(nid);
}

-/**
- * numa_cleanup_meminfo - Cleanup a numa_meminfo
- * @mi: numa_meminfo to clean up
- *
- * Sanitize @mi by merging and removing unnecessary memblks. Also check for
- * conflicts and clear unused memblks.
- *
- * RETURNS:
- * 0 on success, -errno on failure.
- */
-int __init numa_cleanup_meminfo(struct numa_meminfo *mi)
-{
- const u64 low = 0;
- const u64 high = PFN_PHYS(max_pfn);
- int i, j, k;
-
- /* first, trim all entries */
- for (i = 0; i < mi->nr_blks; i++) {
- struct numa_memblk *bi = &mi->blk[i];
-
- /* move / save reserved memory ranges */
- if (!memblock_overlaps_region(&memblock.memory,
- bi->start, bi->end - bi->start)) {
- numa_move_tail_memblk(&numa_reserved_meminfo, i--, mi);
- continue;
- }
-
- /* make sure all non-reserved blocks are inside the limits */
- bi->start = max(bi->start, low);
-
- /* preserve info for non-RAM areas above 'max_pfn': */
- if (bi->end > high) {
- numa_add_memblk_to(bi->nid, high, bi->end,
- &numa_reserved_meminfo);
- bi->end = high;
- }
-
- /* and there's no empty block */
- if (bi->start >= bi->end)
- numa_remove_memblk_from(i--, mi);
- }
-
- /* merge neighboring / overlapping entries */
- for (i = 0; i < mi->nr_blks; i++) {
- struct numa_memblk *bi = &mi->blk[i];
-
- for (j = i + 1; j < mi->nr_blks; j++) {
- struct numa_memblk *bj = &mi->blk[j];
- u64 start, end;
-
- /*
- * See whether there are overlapping blocks. Whine
- * about but allow overlaps of the same nid. They
- * will be merged below.
- */
- if (bi->end > bj->start && bi->start < bj->end) {
- if (bi->nid != bj->nid) {
- pr_err("node %d [mem %#010Lx-%#010Lx] overlaps with node %d [mem %#010Lx-%#010Lx]\n",
- bi->nid, bi->start, bi->end - 1,
- bj->nid, bj->start, bj->end - 1);
- return -EINVAL;
- }
- pr_warn("Warning: node %d [mem %#010Lx-%#010Lx] overlaps with itself [mem %#010Lx-%#010Lx]\n",
- bi->nid, bi->start, bi->end - 1,
- bj->start, bj->end - 1);
- }
-
- /*
- * Join together blocks on the same node, holes
- * between which don't overlap with memory on other
- * nodes.
- */
- if (bi->nid != bj->nid)
- continue;
- start = min(bi->start, bj->start);
- end = max(bi->end, bj->end);
- for (k = 0; k < mi->nr_blks; k++) {
- struct numa_memblk *bk = &mi->blk[k];
-
- if (bi->nid == bk->nid)
- continue;
- if (start < bk->end && end > bk->start)
- break;
- }
- if (k < mi->nr_blks)
- continue;
- printk(KERN_INFO "NUMA: Node %d [mem %#010Lx-%#010Lx] + [mem %#010Lx-%#010Lx] -> [mem %#010Lx-%#010Lx]\n",
- bi->nid, bi->start, bi->end - 1, bj->start,
- bj->end - 1, start, end - 1);
- bi->start = start;
- bi->end = end;
- numa_remove_memblk_from(j--, mi);
- }
- }
-
- /* clear unused ones */
- for (i = mi->nr_blks; i < ARRAY_SIZE(mi->blk); i++) {
- mi->blk[i].start = mi->blk[i].end = 0;
- mi->blk[i].nid = NUMA_NO_NODE;
- }
-
- return 0;
-}
-
-/*
- * Set nodes, which have memory in @mi, in *@nodemask.
- */
-static void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
- const struct numa_meminfo *mi)
-{
- int i;
-
- for (i = 0; i < ARRAY_SIZE(mi->blk); i++)
- if (mi->blk[i].start != mi->blk[i].end &&
- mi->blk[i].nid != NUMA_NO_NODE)
- node_set(mi->blk[i].nid, *nodemask);
-}
-
/**
* numa_reset_distance - Reset NUMA distance table
*
@@ -478,72 +332,6 @@ static bool __init numa_meminfo_cover_memory(const struct numa_meminfo *mi)
return true;
}

-/*
- * Mark all currently memblock-reserved physical memory (which covers the
- * kernel's own memory ranges) as hot-unswappable.
- */
-static void __init numa_clear_kernel_node_hotplug(void)
-{
- nodemask_t reserved_nodemask = NODE_MASK_NONE;
- struct memblock_region *mb_region;
- int i;
-
- /*
- * We have to do some preprocessing of memblock regions, to
- * make them suitable for reservation.
- *
- * At this time, all memory regions reserved by memblock are
- * used by the kernel, but those regions are not split up
- * along node boundaries yet, and don't necessarily have their
- * node ID set yet either.
- *
- * So iterate over all memory known to the x86 architecture,
- * and use those ranges to set the nid in memblock.reserved.
- * This will split up the memblock regions along node
- * boundaries and will set the node IDs as well.
- */
- for (i = 0; i < numa_meminfo.nr_blks; i++) {
- struct numa_memblk *mb = numa_meminfo.blk + i;
- int ret;
-
- ret = memblock_set_node(mb->start, mb->end - mb->start, &memblock.reserved, mb->nid);
- WARN_ON_ONCE(ret);
- }
-
- /*
- * Now go over all reserved memblock regions, to construct a
- * node mask of all kernel reserved memory areas.
- *
- * [ Note, when booting with mem=nn[kMG] or in a kdump kernel,
- * numa_meminfo might not include all memblock.reserved
- * memory ranges, because quirks such as trim_snb_memory()
- * reserve specific pages for Sandy Bridge graphics. ]
- */
- for_each_reserved_mem_region(mb_region) {
- int nid = memblock_get_region_node(mb_region);
-
- if (nid != MAX_NUMNODES)
- node_set(nid, reserved_nodemask);
- }
-
- /*
- * Finally, clear the MEMBLOCK_HOTPLUG flag for all memory
- * belonging to the reserved node mask.
- *
- * Note that this will include memory regions that reside
- * on nodes that contain kernel memory - entire nodes
- * become hot-unpluggable:
- */
- for (i = 0; i < numa_meminfo.nr_blks; i++) {
- struct numa_memblk *mb = numa_meminfo.blk + i;
-
- if (!node_isset(mb->nid, reserved_nodemask))
- continue;
-
- memblock_clear_hotplug(mb->start, mb->end - mb->start);
- }
-}
-
static int __init numa_register_memblks(struct numa_meminfo *mi)
{
int i, nid;
diff --git a/arch/x86/mm/numa_internal.h b/arch/x86/mm/numa_internal.h
index 86860f279662..b6053beb81b1 100644
--- a/arch/x86/mm/numa_internal.h
+++ b/arch/x86/mm/numa_internal.h
@@ -16,19 +16,13 @@ struct numa_meminfo {
struct numa_memblk blk[NR_NODE_MEMBLKS];
};

-void __init numa_remove_memblk_from(int idx, struct numa_meminfo *mi);
-int __init numa_cleanup_meminfo(struct numa_meminfo *mi);
+extern int __init numa_cleanup_meminfo(struct numa_meminfo *mi);
void __init numa_reset_distance(void);

void __init x86_numa_init(void);

-#ifdef CONFIG_NUMA_EMU
-void __init numa_emulation(struct numa_meminfo *numa_meminfo,
- int numa_dist_cnt);
-#else
-static inline void numa_emulation(struct numa_meminfo *numa_meminfo,
- int numa_dist_cnt)
-{ }
-#endif
+extern void __init numa_emulation(struct numa_meminfo *numa_meminfo,
+ int numa_dist_cnt);
+

#endif /* __X86_MM_NUMA_INTERNAL_H */
diff --git a/include/asm-generic/numa.h b/include/asm-generic/numa.h
index 1a3ad6d29833..929d7c582a73 100644
--- a/include/asm-generic/numa.h
+++ b/include/asm-generic/numa.h
@@ -39,6 +39,24 @@ void numa_store_cpu_info(unsigned int cpu);
void numa_add_cpu(unsigned int cpu);
void numa_remove_cpu(unsigned int cpu);

+struct numa_memblk {
+ u64 start;
+ u64 end;
+ int nid;
+};
+
+struct numa_meminfo {
+ int nr_blks;
+ struct numa_memblk blk[NR_NODE_MEMBLKS];
+};
+
+extern struct numa_meminfo numa_meminfo;
+
+int __init numa_register_memblks(struct numa_meminfo *mi);
+int __init numa_cleanup_meminfo(struct numa_meminfo *mi);
+void __init numa_emulation(struct numa_meminfo *numa_meminfo,
+ int numa_dist_cnt);
+
#else /* CONFIG_NUMA */

static inline void numa_store_cpu_info(unsigned int cpu) { }
diff --git a/mm/Makefile b/mm/Makefile
index ec65984e2ade..6fc1bd7c9f5b 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -138,3 +138,4 @@ obj-$(CONFIG_IO_MAPPING) += io-mapping.o
obj-$(CONFIG_HAVE_BOOTMEM_INFO_NODE) += bootmem_info.o
obj-$(CONFIG_GENERIC_IOREMAP) += ioremap.o
obj-$(CONFIG_SHRINKER_DEBUG) += shrinker_debug.o
+obj-$(CONFIG_NUMA) += numa.o
diff --git a/mm/numa.c b/mm/numa.c
new file mode 100644
index 000000000000..88277e8404f0
--- /dev/null
+++ b/mm/numa.c
@@ -0,0 +1,298 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/acpi.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/memblock.h>
+#include <linux/mmzone.h>
+#include <linux/ctype.h>
+#include <linux/nodemask.h>
+#include <linux/sched.h>
+#include <linux/topology.h>
+
+#include <asm/dma.h>
+
+struct numa_meminfo numa_meminfo __initdata_or_meminfo;
+struct numa_meminfo numa_reserved_meminfo __initdata_or_meminfo;
+
+/*
+ * Set nodes, which have memory in @mi, in *@nodemask.
+ */
+void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
+ const struct numa_meminfo *mi)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(mi->blk); i++)
+ if (mi->blk[i].start != mi->blk[i].end &&
+ mi->blk[i].nid != NUMA_NO_NODE)
+ node_set(mi->blk[i].nid, *nodemask);
+}
+
+/**
+ * numa_remove_memblk_from - Remove one numa_memblk from a numa_meminfo
+ * @idx: Index of memblk to remove
+ * @mi: numa_meminfo to remove memblk from
+ *
+ * Remove @idx'th numa_memblk from @mi by shifting @mi->blk[] and
+ * decrementing @mi->nr_blks.
+ */
+static void __init numa_remove_memblk_from(int idx, struct numa_meminfo *mi)
+{
+ mi->nr_blks--;
+ memmove(&mi->blk[idx], &mi->blk[idx + 1],
+ (mi->nr_blks - idx) * sizeof(mi->blk[0]));
+}
+
+/**
+ * numa_move_tail_memblk - Move a numa_memblk from one numa_meminfo to another
+ * @dst: numa_meminfo to append block to
+ * @idx: Index of memblk to remove
+ * @src: numa_meminfo to remove memblk from
+ */
+static void __init numa_move_tail_memblk(struct numa_meminfo *dst, int idx,
+ struct numa_meminfo *src)
+{
+ dst->blk[dst->nr_blks++] = src->blk[idx];
+ numa_remove_memblk_from(idx, src);
+}
+
+int __init numa_add_memblk_to(int nid, u64 start, u64 end,
+ struct numa_meminfo *mi)
+{
+ /* ignore zero length blks */
+ if (start == end)
+ return 0;
+
+ /* whine about and ignore invalid blks */
+ if (start > end || nid < 0 || nid >= MAX_NUMNODES) {
+ pr_warn("Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
+ nid, start, end - 1);
+ return 0;
+ }
+
+ if (mi->nr_blks >= NR_NODE_MEMBLKS) {
+ pr_err("too many memblk ranges\n");
+ return -EINVAL;
+ }
+
+ mi->blk[mi->nr_blks].start = start;
+ mi->blk[mi->nr_blks].end = end;
+ mi->blk[mi->nr_blks].nid = nid;
+ mi->nr_blks++;
+ return 0;
+}
+
+/**
+ * numa_cleanup_meminfo - Cleanup a numa_meminfo
+ * @mi: numa_meminfo to clean up
+ *
+ * Sanitize @mi by merging and removing unnecessary memblks. Also check for
+ * conflicts and clear unused memblks.
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int __init numa_cleanup_meminfo(struct numa_meminfo *mi)
+{
+ const u64 low = 0;
+ const u64 high = PFN_PHYS(max_pfn);
+ int i, j, k;
+
+ /* first, trim all entries */
+ for (i = 0; i < mi->nr_blks; i++) {
+ struct numa_memblk *bi = &mi->blk[i];
+
+ /* move / save reserved memory ranges */
+ if (!memblock_overlaps_region(&memblock.memory,
+ bi->start, bi->end - bi->start)) {
+ numa_move_tail_memblk(&numa_reserved_meminfo, i--, mi);
+ continue;
+ }
+
+ /* make sure all non-reserved blocks are inside the limits */
+ bi->start = max(bi->start, low);
+
+ /* preserve info for non-RAM areas above 'max_pfn': */
+ if (bi->end > high) {
+ numa_add_memblk_to(bi->nid, high, bi->end,
+ &numa_reserved_meminfo);
+ bi->end = high;
+ }
+
+ /* and there's no empty block */
+ if (bi->start >= bi->end)
+ numa_remove_memblk_from(i--, mi);
+ }
+
+ /* merge neighboring / overlapping entries */
+ for (i = 0; i < mi->nr_blks; i++) {
+ struct numa_memblk *bi = &mi->blk[i];
+
+ for (j = i + 1; j < mi->nr_blks; j++) {
+ struct numa_memblk *bj = &mi->blk[j];
+ u64 start, end;
+
+ /*
+ * See whether there are overlapping blocks. Whine
+ * about but allow overlaps of the same nid. They
+ * will be merged below.
+ */
+ if (bi->end > bj->start && bi->start < bj->end) {
+ if (bi->nid != bj->nid) {
+ pr_err("node %d [mem %#010Lx-%#010Lx] overlaps with node %d [mem %#010Lx-%#010Lx]\n",
+ bi->nid, bi->start, bi->end - 1,
+ bj->nid, bj->start, bj->end - 1);
+ return -EINVAL;
+ }
+ pr_warn("Warning: node %d [mem %#010Lx-%#010Lx] overlaps with itself [mem %#010Lx-%#010Lx]\n",
+ bi->nid, bi->start, bi->end - 1,
+ bj->start, bj->end - 1);
+ }
+
+ /*
+ * Join together blocks on the same node, holes
+ * between which don't overlap with memory on other
+ * nodes.
+ */
+ if (bi->nid != bj->nid)
+ continue;
+ start = min(bi->start, bj->start);
+ end = max(bi->end, bj->end);
+ for (k = 0; k < mi->nr_blks; k++) {
+ struct numa_memblk *bk = &mi->blk[k];
+
+ if (bi->nid == bk->nid)
+ continue;
+ if (start < bk->end && end > bk->start)
+ break;
+ }
+ if (k < mi->nr_blks)
+ continue;
+ printk(KERN_INFO "NUMA: Node %d [mem %#010Lx-%#010Lx] + [mem %#010Lx-%#010Lx] -> [mem %#010Lx-%#010Lx]\n",
+ bi->nid, bi->start, bi->end - 1, bj->start,
+ bj->end - 1, start, end - 1);
+ bi->start = start;
+ bi->end = end;
+ numa_remove_memblk_from(j--, mi);
+ }
+ }
+
+ /* clear unused ones */
+ for (i = mi->nr_blks; i < ARRAY_SIZE(mi->blk); i++) {
+ mi->blk[i].start = mi->blk[i].end = 0;
+ mi->blk[i].nid = NUMA_NO_NODE;
+ }
+
+ return 0;
+}
+
+/*
+ * Mark all currently memblock-reserved physical memory (which covers the
+ * kernel's own memory ranges) as hot-unswappable.
+ */
+static void __init numa_clear_kernel_node_hotplug(void)
+{
+ nodemask_t reserved_nodemask = NODE_MASK_NONE;
+ struct memblock_region *mb_region;
+ int i;
+
+ /*
+ * We have to do some preprocessing of memblock regions, to
+ * make them suitable for reservation.
+ *
+ * At this time, all memory regions reserved by memblock are
+ * used by the kernel, but those regions are not split up
+ * along node boundaries yet, and don't necessarily have their
+ * node ID set yet either.
+ *
+ * So iterate over all memory known to the x86 architecture,
+ * and use those ranges to set the nid in memblock.reserved.
+ * This will split up the memblock regions along node
+ * boundaries and will set the node IDs as well.
+ */
+ for (i = 0; i < numa_meminfo.nr_blks; i++) {
+ struct numa_memblk *mb = numa_meminfo.blk + i;
+ int ret;
+
+ ret = memblock_set_node(mb->start, mb->end - mb->start, &memblock.reserved, mb->nid);
+ WARN_ON_ONCE(ret);
+ }
+
+ /*
+ * Now go over all reserved memblock regions, to construct a
+ * node mask of all kernel reserved memory areas.
+ *
+ * [ Note, when booting with mem=nn[kMG] or in a kdump kernel,
+ * numa_meminfo might not include all memblock.reserved
+ * memory ranges, because quirks such as trim_snb_memory()
+ * reserve specific pages for Sandy Bridge graphics. ]
+ */
+ for_each_reserved_mem_region(mb_region) {
+ int nid = memblock_get_region_node(mb_region);
+
+ if (nid != MAX_NUMNODES)
+ node_set(nid, reserved_nodemask);
+ }
+
+ /*
+ * Finally, clear the MEMBLOCK_HOTPLUG flag for all memory
+ * belonging to the reserved node mask.
+ *
+ * Note that this will include memory regions that reside
+ * on nodes that contain kernel memory - entire nodes
+ * become hot-unpluggable:
+ */
+ for (i = 0; i < numa_meminfo.nr_blks; i++) {
+ struct numa_memblk *mb = numa_meminfo.blk + i;
+
+ if (!node_isset(mb->nid, reserved_nodemask))
+ continue;
+
+ memblock_clear_hotplug(mb->start, mb->end - mb->start);
+ }
+}
+
+int __weak __init numa_register_memblks(struct numa_meminfo *mi)
+{
+ int i;
+
+ /* Account for nodes with cpus and no memory */
+ node_possible_map = numa_nodes_parsed;
+ numa_nodemask_from_meminfo(&node_possible_map, mi);
+ if (WARN_ON(nodes_empty(node_possible_map)))
+ return -EINVAL;
+
+ for (i = 0; i < mi->nr_blks; i++) {
+ struct numa_memblk *mb = &mi->blk[i];
+ memblock_set_node(mb->start, mb->end - mb->start,
+ &memblock.memory, mb->nid);
+ }
+
+ /*
+ * At very early time, the kernel have to use some memory such as
+ * loading the kernel image. We cannot prevent this anyway. So any
+ * node the kernel resides in should be un-hotpluggable.
+ *
+ * And when we come here, alloc node data won't fail.
+ */
+ numa_clear_kernel_node_hotplug();
+
+ /*
+ * If sections array is gonna be used for pfn -> nid mapping, check
+ * whether its granularity is fine enough.
+ */
+ if (IS_ENABLED(NODE_NOT_IN_PAGE_FLAGS)) {
+ 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",
+ PFN_PHYS(pfn_align) >> 20,
+ PFN_PHYS(PAGES_PER_SECTION) >> 20);
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
--
2.32.0.3.gf3a3e56d6