diff mbox series

[V3,2/2] pseries/initnodes: Ensure nodes initialized for hotplug

Message ID 8d171641-b2ed-77f4-fc3f-2b5e4a56c4e8@linux.vnet.ibm.com (mailing list archive)
State Superseded
Headers show
Series pseries/nodes: Fix issues with memoryless nodes | expand

Commit Message

Michael Bringmann Oct. 23, 2017, 1:46 p.m. UTC 
To: linuxppc-dev@lists.ozlabs.org
To: linux-kernel@vger.kernel.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Bringmann <mwb@linux.vnet.ibm.com>
Cc: John Allen <jallen@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Subject: [PATCH V3 2/2] pseries/initnodes: Ensure nodes initialized for hotplug

pseries/nodes: On pseries systems which allow 'hot-add' of CPU,
it may occur that the new resources are to be inserted into nodes
that were not used for memory resources at bootup.  Many different
configurations of PowerPC resources may need to be supported depending
upon the environment.  This patch fixes some problems encountered at
runtime with configurations that support memory-less nodes, or that
hot-add resources during system execution after boot.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
---
 arch/powerpc/mm/numa.c |   35 +++++++++++++++++++++++++++++++++--
 1 file changed, 33 insertions(+), 2 deletions(-)

Comments

kernel test robot Oct. 24, 2017, 8:26 p.m. UTC | #1 
Hi Michael,

[auto build test WARNING on powerpc/next]
[also build test WARNING on v4.14-rc6 next-20171018]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Michael-Bringmann/pseries-nodes-Ensure-enough-nodes-avail-for-operations/20171024-021023
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-allyesconfig (attached as .config)
compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=powerpc 

All warnings (new ones prefixed by >>):

>> WARNING: vmlinux.o(.text+0x820e0): Section mismatch in reference from the function .numa_update_cpu_topology() to the function .init.text:.setup_node_data()
   The function .numa_update_cpu_topology() references
   the function __init .setup_node_data().
   This is often because .numa_update_cpu_topology lacks a __init
   annotation or the annotation of .setup_node_data is wrong.

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
diff mbox series

Patch

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index f885ab7..37f697dc1 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -551,7 +551,7 @@  static int numa_setup_cpu(unsigned long lcpu)
 	nid = of_node_to_nid_single(cpu);
 
 out_present:
-	if (nid < 0 || !node_online(nid))
+	if (nid < 0 || !node_possible(nid))
 		nid = first_online_node;
 
 	map_cpu_to_node(lcpu, nid);
@@ -1311,6 +1311,35 @@  static long vphn_get_associativity(unsigned long cpu,
 	return rc;
 }
 
+static int verify_node_preparation(int nid)
+{
+	/*
+	 * Need to allocate/initialize NODE_DATA from a node with
+	 * memory (see memblock_alloc_try_nid).  Code executed after
+	 * boot (like local_memory_node) often does not know enough
+	 * to recover fully for memoryless nodes. 
+	 */
+	if (NODE_DATA(nid) == NULL) {
+		int ret;
+		printk(KERN_INFO "%s:%d node %d (%d)\n", __FUNCTION__, __LINE__, nid, first_online_node);
+		setup_node_data(nid, 0, 0);
+		printk(KERN_INFO "%s:%d node %d (%d)\n", __FUNCTION__, __LINE__, nid, first_online_node);
+		ret = try_online_node(nid);
+		printk(KERN_INFO "%s:%d node %d (%d) %d %p\n", __FUNCTION__, __LINE__, nid, first_online_node, ret, NODE_DATA(nid));
+
+		/*
+		 * Node structures successfully initialized, but
+		 * we still need the node to be offline.
+		 */
+		node_set_offline(nid);
+	}
+
+	if (NODE_DATA(nid)->node_spanned_pages == 0)
+		return first_online_node;
+
+	return nid;
+}
+
 /*
  * Update the CPU maps and sysfs entries for a single CPU when its NUMA
  * characteristics change. This function doesn't perform any locking and is
@@ -1419,9 +1448,11 @@  int numa_update_cpu_topology(bool cpus_locked)
 		/* Use associativity from first thread for all siblings */
 		vphn_get_associativity(cpu, associativity);
 		new_nid = associativity_to_nid(associativity);
-		if (new_nid < 0 || !node_online(new_nid))
+		if (new_nid < 0 || !node_possible(new_nid))
 			new_nid = first_online_node;
 
+		new_nid = verify_node_preparation(new_nid);
+
 		if (new_nid == numa_cpu_lookup_table[cpu]) {
 			cpumask_andnot(&cpu_associativity_changes_mask,
 					&cpu_associativity_changes_mask,