From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Fri, 5 Nov 2021 20:40:24 +0000 (-0700)
Subject: mm: move node_reclaim_distance to fix NUMA without SMP
X-Git-Tag: microblaze-v5.18~582^2~152
X-Git-Url: http://git.monstr.eu/?a=commitdiff_plain;h=61bb6cd2f765b90cfc5f0f91696889c366a6a13d;p=linux-2.6-microblaze.git

mm: move node_reclaim_distance to fix NUMA without SMP

Patch series "Fix NUMA without SMP".

SuperH is the only architecture which still supports NUMA without SMP,
for good reasons (various memories scattered around the address space,
each with varying latencies).

This series fixes two build errors due to variables and functions used
by the NUMA code being provided by SMP-only source files or sections.

This patch (of 2):

If CONFIG_NUMA=y, but CONFIG_SMP=n (e.g. sh/migor_defconfig):

    sh4-linux-gnu-ld: mm/page_alloc.o: in function `get_page_from_freelist':
    page_alloc.c:(.text+0x2c24): undefined reference to `node_reclaim_distance'

Fix this by moving the declaration of node_reclaim_distance from an
SMP-only to a generic file.

Link: https://lkml.kernel.org/r/cover.1631781495.git.geert+renesas@glider.be
Link: https://lkml.kernel.org/r/6432666a648dde85635341e6c918cee97c97d264.1631781495.git.geert+renesas@glider.be
Fixes: a55c7454a8c887b2 ("sched/topology: Improve load balancing on AMD EPYC systems")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Suggested-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Cc: Rich Felker <dalias@libc.org>
Cc: Gon Solo <gonsolo@gmail.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index 4e8698e62f07..738ee7fa7972 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1481,7 +1481,6 @@ static int			sched_domains_curr_level;
 int				sched_max_numa_distance;
 static int			*sched_domains_numa_distance;
 static struct cpumask		***sched_domains_numa_masks;
-int __read_mostly		node_reclaim_distance = RECLAIM_DISTANCE;
 
 static unsigned long __read_mostly *sched_numa_onlined_nodes;
 #endif
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 1eab16b4006d..e4aef907abe9 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3960,6 +3960,8 @@ bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
 }
 
 #ifdef CONFIG_NUMA
+int __read_mostly node_reclaim_distance = RECLAIM_DISTANCE;
+
 static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone)
 {
 	return node_distance(zone_to_nid(local_zone), zone_to_nid(zone)) <=