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authorAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>2023-04-04 07:14:33 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-04-20 13:10:28 +0300
commitccbec01cc99ce0d3a6851a5cea2fa1c05e536236 (patch)
tree6822274467eb7ee8caddb19d400b840aa3b58c02 /arch/powerpc/mm/numa.c
parent453b3188be89a413efd7bad4ceb1f78a4716475b (diff)
downloadlinux-ccbec01cc99ce0d3a6851a5cea2fa1c05e536236.tar.xz
powerpc/papr_scm: Update the NUMA distance table for the target node
[ Upstream commit b277fc793daf258877b4c0744b52f69d6e6ba22e ] Platform device helper routines won't update the NUMA distance table while creating a platform device, even if the device is present on a NUMA node that doesn't have memory or CPU. This is especially true for pmem devices. If the target node of the pmem device is not online, we find the nearest online node to the device and associate the pmem device with that online node. To find the nearest online node, we should have the numa distance table updated correctly. Update the distance information during the device probe. For a papr scm device on NUMA node 3 distance_lookup_table value for distance_ref_points_depth = 2 before and after fix is below: Before fix: node 3 distance depth 0 - 0 node 3 distance depth 1 - 0 node 4 distance depth 0 - 4 node 4 distance depth 1 - 2 node 5 distance depth 0 - 5 node 5 distance depth 1 - 1 After fix node 3 distance depth 0 - 3 node 3 distance depth 1 - 1 node 4 distance depth 0 - 4 node 4 distance depth 1 - 2 node 5 distance depth 0 - 5 node 5 distance depth 1 - 1 Without the fix, the nearest numa node to the pmem device (NUMA node 3) will be picked as 4. After the fix, we get the correct numa node which is 5. Fixes: da1115fdbd6e ("powerpc/nvdimm: Pick nearby online node if the device node is not online") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230404041433.1781804-1-aneesh.kumar@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/powerpc/mm/numa.c')
-rw-r--r--arch/powerpc/mm/numa.c1
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index cfc170935a58..ce8569e16f0c 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -372,6 +372,7 @@ void update_numa_distance(struct device_node *node)
WARN(numa_distance_table[nid][nid] == -1,
"NUMA distance details for node %d not provided\n", nid);
}
+EXPORT_SYMBOL_GPL(update_numa_distance);
/*
* ibm,numa-lookup-index-table= {N, domainid1, domainid2, ..... domainidN}