[tip:x86/debug] x86/numa_emulation: Recalculate numa_nodes_parsed from emulated nodes

[tip-bot for Wei Yang]

Commit-ID:  4f167201edda7cd7525cc7f23944731ef5dd99a8
Gitweb:     http://git.kernel.org/tip/4f167201edda7cd7525cc7f23944731ef5dd99a8
Author:     Wei Yang <richard.weiyang@xxxxxxxxx>
AuthorDate: Sat, 8 Jul 2017 09:30:59 +0800
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 18 Jul 2017 11:16:49 +0200

x86/numa_emulation: Recalculate numa_nodes_parsed from emulated nodes

When emulating NUMA, the kernel's emulated NUMA configuration may contain
more or less nodes than there are physical nodes.

In numa_emulation(), we recalculate numa_meminfo/numa_distance/__apicid_to_node
according to the number of emulated nodes, except numa_nodes_parsed, which is
arguably an omission.

Recalculate numa_nodes_parsed as well.

Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: bp@xxxxxxxxx
Cc: kirill@xxxxxxxxxxxxx
Cc: tj@xxxxxxxxxx
Link: http://lkml.kernel.org/r/20170708013059.29708-4-richard.weiyang@xxxxxxxxx
[ Changelog fixes. ]
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 arch/x86/mm/numa_emulation.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c
index 80904ed..d805162 100644
--- a/arch/x86/mm/numa_emulation.c
+++ b/arch/x86/mm/numa_emulation.c
@@ -395,6 +395,13 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
 	/* commit */
 	*numa_meminfo = ei;
 
+	/* Make sure numa_nodes_parsed only contains emulated nodes */
+	nodes_clear(numa_nodes_parsed);
+	for (i = 0; i < ARRAY_SIZE(ei.blk); i++)
+		if (ei.blk[i].start != ei.blk[i].end &&
+		    ei.blk[i].nid != NUMA_NO_NODE)
+			node_set(ei.blk[i].nid, numa_nodes_parsed);
+
 	/*
 	 * Transform __apicid_to_node table to use emulated nids by
 	 * reverse-mapping phys_nid.  The maps should always exist but fall