hugetlbfs: extend the definition of hugepages parameter to support node allocation

We can specify the number of hugepages to allocate at boot.  But the
hugepages is balanced in all nodes at present.  In some scenarios, we
only need hugepages in one node.  For example: DPDK needs hugepages
which are in the same node as NIC.

If DPDK needs four hugepages of 1G size in node1 and system has 16 numa
nodes we must reserve 64 hugepages on the kernel cmdline.  But only four
hugepages are used.  The others should be free after boot.  If the
system memory is low(for example: 64G), it will be an impossible task.

So extend the hugepages parameter to support specifying hugepages on a
specific node.  For example add following parameter:

  hugepagesz=1G hugepages=0:1,1:3

It will allocate 1 hugepage in node0 and 3 hugepages in node1.

Link: https://lkml.kernel.org/r/20211005054729.86457-1-yaozhenguo1@gmail.com
Signed-off-by: Zhenguo Yao <yaozhenguo1@gmail.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Zhenguo Yao <yaozhenguo1@gmail.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 128 insertions, 25 deletions

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 5eab627a170b..24543dab9c4b 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -77,6 +77,7 @@ static struct hstate * __initdata parsed_hstate;
 static unsigned long __initdata default_hstate_max_huge_pages;
 static bool __initdata parsed_valid_hugepagesz = true;
 static bool __initdata parsed_default_hugepagesz;
+static unsigned int default_hugepages_in_node[MAX_NUMNODES] __initdata;
 
 /*
  * Protects updates to hugepage_freelists, hugepage_activelist, nr_huge_pages,
@@ -2963,33 +2964,39 @@ out_subpool_put:
 	return ERR_PTR(-ENOSPC);
 }
 
-int alloc_bootmem_huge_page(struct hstate *h)
+int alloc_bootmem_huge_page(struct hstate *h, int nid)
 	__attribute__ ((weak, alias("__alloc_bootmem_huge_page")));
-int __alloc_bootmem_huge_page(struct hstate *h)
+int __alloc_bootmem_huge_page(struct hstate *h, int nid)
 {
-	struct huge_bootmem_page *m;
+	struct huge_bootmem_page *m = NULL; /* initialize for clang */
 	int nr_nodes, node;
 
+	if (nid >= nr_online_nodes)
+		return 0;
+	/* do node specific alloc */
+	if (nid != NUMA_NO_NODE) {
+		m = memblock_alloc_try_nid_raw(huge_page_size(h), huge_page_size(h),
+				0, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
+		if (!m)
+			return 0;
+		goto found;
+	}
+	/* allocate from next node when distributing huge pages */
 	for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) {
-		void *addr;
-
-		addr = memblock_alloc_try_nid_raw(
+		m = memblock_alloc_try_nid_raw(
 				huge_page_size(h), huge_page_size(h),
 				0, MEMBLOCK_ALLOC_ACCESSIBLE, node);
-		if (addr) {
-			/*
-			 * Use the beginning of the huge page to store the
-			 * huge_bootmem_page struct (until gather_bootmem
-			 * puts them into the mem_map).
-			 */
-			m = addr;
-			goto found;
-		}
+		/*
+		 * Use the beginning of the huge page to store the
+		 * huge_bootmem_page struct (until gather_bootmem
+		 * puts them into the mem_map).
+		 */
+		if (!m)
+			return 0;
+		goto found;
 	}
-	return 0;
 
 found:
-	BUG_ON(!IS_ALIGNED(virt_to_phys(m), huge_page_size(h)));
 	/* Put them into a private list first because mem_map is not up yet */
 	INIT_LIST_HEAD(&m->list);
 	list_add(&m->list, &huge_boot_pages);
@@ -3029,12 +3036,61 @@ static void __init gather_bootmem_prealloc(void)
 		cond_resched();
 	}
 }
+static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid)
+{
+	unsigned long i;
+	char buf[32];
+
+	for (i = 0; i < h->max_huge_pages_node[nid]; ++i) {
+		if (hstate_is_gigantic(h)) {
+			if (!alloc_bootmem_huge_page(h, nid))
+				break;
+		} else {
+			struct page *page;
+			gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE;
+
+			page = alloc_fresh_huge_page(h, gfp_mask, nid,
+					&node_states[N_MEMORY], NULL);
+			if (!page)
+				break;
+			put_page(page); /* free it into the hugepage allocator */
+		}
+		cond_resched();
+	}
+	if (i == h->max_huge_pages_node[nid])
+		return;
+
+	string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32);
+	pr_warn("HugeTLB: allocating %u of page size %s failed node%d.  Only allocated %lu hugepages.\n",
+		h->max_huge_pages_node[nid], buf, nid, i);
+	h->max_huge_pages -= (h->max_huge_pages_node[nid] - i);
+	h->max_huge_pages_node[nid] = i;
+}
 
 static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
 {
 	unsigned long i;
 	nodemask_t *node_alloc_noretry;
+	bool node_specific_alloc = false;
 
+	/* skip gigantic hugepages allocation if hugetlb_cma enabled */
+	if (hstate_is_gigantic(h) && hugetlb_cma_size) {
+		pr_warn_once("HugeTLB: hugetlb_cma is enabled, skip boot time allocation\n");
+		return;
+	}
+
+	/* do node specific alloc */
+	for (i = 0; i < nr_online_nodes; i++) {
+		if (h->max_huge_pages_node[i] > 0) {
+			hugetlb_hstate_alloc_pages_onenode(h, i);
+			node_specific_alloc = true;
+		}
+	}
+
+	if (node_specific_alloc)
+		return;
+
+	/* below will do all node balanced alloc */
 	if (!hstate_is_gigantic(h)) {
 		/*
 		 * Bit mask controlling how hard we retry per-node allocations.
@@ -3055,11 +3111,7 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
 
 	for (i = 0; i < h->max_huge_pages; ++i) {
 		if (hstate_is_gigantic(h)) {
-			if (hugetlb_cma_size) {
-				pr_warn_once("HugeTLB: hugetlb_cma is enabled, skip boot time allocation\n");
-				goto free;
-			}
-			if (!alloc_bootmem_huge_page(h))
+			if (!alloc_bootmem_huge_page(h, NUMA_NO_NODE))
 				break;
 		} else if (!alloc_pool_huge_page(h,
 					 &node_states[N_MEMORY],
@@ -3075,7 +3127,6 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
 			h->max_huge_pages, buf, i);
 		h->max_huge_pages = i;
 	}
-free:
 	kfree(node_alloc_noretry);
 }
 
@@ -3990,6 +4041,10 @@ static int __init hugetlb_init(void)
 			}
 			default_hstate.max_huge_pages =
 				default_hstate_max_huge_pages;
+
+			for (i = 0; i < nr_online_nodes; i++)
+				default_hstate.max_huge_pages_node[i] =
+					default_hugepages_in_node[i];
 		}
 	}
 
@@ -4050,6 +4105,10 @@ void __init hugetlb_add_hstate(unsigned int order)
 	parsed_hstate = h;
 }
 
+bool __init __weak hugetlb_node_alloc_supported(void)
+{
+	return true;
+}
 /*
  * hugepages command line processing
  * hugepages normally follows a valid hugepagsz or default_hugepagsz
@@ -4061,6 +4120,10 @@ static int __init hugepages_setup(char *s)
 {
 	unsigned long *mhp;
 	static unsigned long *last_mhp;
+	int node = NUMA_NO_NODE;
+	int count;
+	unsigned long tmp;
+	char *p = s;
 
 	if (!parsed_valid_hugepagesz) {
 		pr_warn("HugeTLB: hugepages=%s does not follow a valid hugepagesz, ignoring\n", s);
@@ -4084,8 +4147,40 @@ static int __init hugepages_setup(char *s)
 		return 0;
 	}
 
-	if (sscanf(s, "%lu", mhp) <= 0)
-		*mhp = 0;
+	while (*p) {
+		count = 0;
+		if (sscanf(p, "%lu%n", &tmp, &count) != 1)
+			goto invalid;
+		/* Parameter is node format */
+		if (p[count] == ':') {
+			if (!hugetlb_node_alloc_supported()) {
+				pr_warn("HugeTLB: architecture can't support node specific alloc, ignoring!\n");
+				return 0;
+			}
+			node = tmp;
+			p += count + 1;
+			if (node < 0 || node >= nr_online_nodes)
+				goto invalid;
+			/* Parse hugepages */
+			if (sscanf(p, "%lu%n", &tmp, &count) != 1)
+				goto invalid;
+			if (!hugetlb_max_hstate)
+				default_hugepages_in_node[node] = tmp;
+			else
+				parsed_hstate->max_huge_pages_node[node] = tmp;
+			*mhp += tmp;
+			/* Go to parse next node*/
+			if (p[count] == ',')
+				p += count + 1;
+			else
+				break;
+		} else {
+			if (p != s)
+				goto invalid;
+			*mhp = tmp;
+			break;
+		}
+	}
 
 	/*
 	 * Global state is always initialized later in hugetlb_init.
@@ -4098,6 +4193,10 @@ static int __init hugepages_setup(char *s)
 	last_mhp = mhp;
 
 	return 1;
+
+invalid:
+	pr_warn("HugeTLB: Invalid hugepages parameter %s\n", p);
+	return 0;
 }
 __setup("hugepages=", hugepages_setup);
 
@@ -4159,6 +4258,7 @@ __setup("hugepagesz=", hugepagesz_setup);
 static int __init default_hugepagesz_setup(char *s)
 {
 	unsigned long size;
+	int i;
 
 	parsed_valid_hugepagesz = false;
 	if (parsed_default_hugepagesz) {
@@ -4187,6 +4287,9 @@ static int __init default_hugepagesz_setup(char *s)
 	 */
 	if (default_hstate_max_huge_pages) {
 		default_hstate.max_huge_pages = default_hstate_max_huge_pages;
+		for (i = 0; i < nr_online_nodes; i++)
+			default_hstate.max_huge_pages_node[i] =
+				default_hugepages_in_node[i];
 		if (hstate_is_gigantic(&default_hstate))
 			hugetlb_hstate_alloc_pages(&default_hstate);
 		default_hstate_max_huge_pages = 0;