Commit 61bb6cd2 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven Committed by Linus Torvalds
Browse files

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: a55c7454 ("sched/topology: Improve load balancing on AMD EPYC systems")
Signed-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
Suggested-by: default avatarMatt Fleming <matt@codeblueprint.co.uk>
Acked-by: default avatarMel 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 54d032ce

kernel/sched/topology.c

+0 −1
Original line number Diff line number Diff line
@@ -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

mm/page_alloc.c

+2 −0
Original line number Diff line number Diff line
@@ -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)) <=