From c537c436782eea29c5beefb4b5ac9956d7e39359 Mon Sep 17 00:00:00 2001
From: Chen Wandun <chenwandun@huawei.com>
Date: Thu, 28 Oct 2021 14:36:24 -0700
Subject: [PATCH] mm/vmalloc: fix numa spreading for large hash tables
References: git fixes (mm/vmalloc)
Patch-mainline: v5.15
Git-commit: ffb29b1c255ab48cb0062a3d11c101501e3e9b3f
Eric Dumazet reported a strange numa spreading info in [1], and found
commit 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings") introduced
this issue [2].
Dig into the difference before and after this patch, page allocation has
some difference:
before:
alloc_large_system_hash
__vmalloc
__vmalloc_node(..., NUMA_NO_NODE, ...)
__vmalloc_node_range
__vmalloc_area_node
alloc_page /* because NUMA_NO_NODE, so choose alloc_page branch */
alloc_pages_current
alloc_page_interleave /* can be proved by print policy mode */
after:
alloc_large_system_hash
__vmalloc
__vmalloc_node(..., NUMA_NO_NODE, ...)
__vmalloc_node_range
__vmalloc_area_node
alloc_pages_node /* choose nid by nuam_mem_id() */
__alloc_pages_node(nid, ....)
So after commit 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings"),
it will allocate memory in current node instead of interleaving allocate
memory.
Link: https://lore.kernel.org/linux-mm/CANn89iL6AAyWhfxdHO+jaT075iOa3XcYn9k6JJc7JR2XYn6k_Q@mail.gmail.com/ [1]
Link: https://lore.kernel.org/linux-mm/CANn89iLofTR=AK-QOZY87RdUZENCZUT4O6a0hvhu3_EwRMerOg@mail.gmail.com/ [2]
Link: https://lkml.kernel.org/r/20211021080744.874701-2-chenwandun@huawei.com
Fixes: 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings")
Signed-off-by: Chen Wandun <chenwandun@huawei.com>
Reported-by: Eric Dumazet <edumazet@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
mm/vmalloc.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 3824dc16ce1c..70faf6d7b16a 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2804,6 +2804,8 @@ vm_area_alloc_pages(gfp_t gfp, int nid,
unsigned int order, unsigned int nr_pages, struct page **pages)
{
unsigned int nr_allocated = 0;
+ struct page *page;
+ int i;
/*
* For order-0 pages we make use of bulk allocator, if
@@ -2811,7 +2813,7 @@ vm_area_alloc_pages(gfp_t gfp, int nid,
* to fails, fallback to a single page allocator that is
* more permissive.
*/
- if (!order) {
+ if (!order && nid != NUMA_NO_NODE) {
while (nr_allocated < nr_pages) {
unsigned int nr, nr_pages_request;
@@ -2836,7 +2838,7 @@ vm_area_alloc_pages(gfp_t gfp, int nid,
if (nr != nr_pages_request)
break;
}
- } else
+ } else if (order)
/*
* Compound pages required for remap_vmalloc_page if
* high-order pages.
@@ -2844,11 +2846,12 @@ vm_area_alloc_pages(gfp_t gfp, int nid,
gfp |= __GFP_COMP;
/* High-order pages or fallback path if "bulk" fails. */
- while (nr_allocated < nr_pages) {
- struct page *page;
- int i;
- page = alloc_pages_node(nid, gfp, order);
+ while (nr_allocated < nr_pages) {
+ if (nid == NUMA_NO_NODE)
+ page = alloc_pages(gfp, order);
+ else
+ page = alloc_pages_node(nid, gfp, order);
if (unlikely(!page))
break;