From 48b63961c84671df4c4a4451c40057e34b26df1a Mon Sep 17 00:00:00 2001 From: Oscar Salvador Date: Mon, 11 Apr 2022 09:49:34 +0200 Subject: powerpc/numa: Associate numa node to its cpu earlier powerpc is the only platform that do not rely on cpu_up()->try_online_node() to bring up a numa node, and special cases it, instead, deep in its own machinery: dlpar_online_cpu find_and_online_cpu_nid try_online_node This should not be needed, but the thing is that the try_online_node() from cpu_up() will not apply on the right node, because cpu_to_node() will return the old mapping numa<->cpu that gets set on boot stage for all possible cpus. That can be seen easily if we try to print out the numa node passed to try_online_node() in cpu_up(). The thing is that the numa<->cpu mapping does not get updated till a much later stage in start_secondary: start_secondary: set_numa_node(numa_cpu_lookup_table[cpu]) But we do not really care, as we already now the CPU <-> NUMA associativity back in find_and_online_cpu_nid(), so let us make use of that and set the proper numa<->cpu mapping, so cpu_to_node() in cpu_up() returns the right node and try_online_node() can do its work. Signed-off-by: Oscar Salvador Tested-by: Geetika Moolchandani Reviewed-by: Srikar Dronamraju Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220411074934.4632-1-osalvador@suse.de --- arch/powerpc/mm/numa.c | 32 ++++++++------------------------ 1 file changed, 8 insertions(+), 24 deletions(-) (limited to 'arch/powerpc/mm/numa.c') diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 4680e310e68a..0801b2ce9b7d 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1422,42 +1422,26 @@ out: return rc; } -int find_and_online_cpu_nid(int cpu) +void find_and_update_cpu_nid(int cpu) { __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0}; int new_nid; /* Use associativity from first thread for all siblings */ if (vphn_get_associativity(cpu, associativity)) - return cpu_to_node(cpu); + return; + /* Do not have previous associativity, so find it now. */ new_nid = associativity_to_nid(associativity); - if (new_nid < 0 || !node_possible(new_nid)) - new_nid = first_online_node; - if (!node_online(new_nid)) { -#ifdef CONFIG_MEMORY_HOTPLUG - /* - * Need to ensure that NODE_DATA is initialized for a node from - * available memory (see memblock_alloc_try_nid). If unable to - * init the node, then default to nearest node that has memory - * installed. Skip onlining a node if the subsystems are not - * yet initialized. - */ - if (!topology_inited || try_online_node(new_nid)) - new_nid = first_online_node; -#else - /* - * Default to using the nearest node that has memory installed. - * Otherwise, it would be necessary to patch the kernel MM code - * to deal with more memoryless-node error conditions. - */ + if (new_nid < 0 || !node_possible(new_nid)) new_nid = first_online_node; -#endif - } + else + // Associate node <-> cpu, so cpu_up() calls + // try_online_node() on the right node. + set_cpu_numa_node(cpu, new_nid); pr_debug("%s:%d cpu %d nid %d\n", __func__, __LINE__, cpu, new_nid); - return new_nid; } int cpu_to_coregroup_id(int cpu) -- cgit v1.2.3-59-g8ed1b