From e6d4a636acdb784f087d6d54fc93dcc952267d47 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Fri, 2 Dec 2016 11:12:01 +0100 Subject: s390/numa: pin all possible cpus to nodes early It is required to have an early static cpu to node mapping. This patch pins all possible cpus to nodes for which no topology information is present. Since there is no interface available which would allow to tell where a non-present cpu would appear topology-wise, simply use a round robin algorithm. Right now this makes sure that the cpu_to_node() function will return the same value for a cpu during the life time of the system. Acked-by: Michael Holzheu Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/numa/mode_emu.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) (limited to 'arch/s390/numa/mode_emu.c') diff --git a/arch/s390/numa/mode_emu.c b/arch/s390/numa/mode_emu.c index 02b840d8f9af..cfd08384f0ab 100644 --- a/arch/s390/numa/mode_emu.c +++ b/arch/s390/numa/mode_emu.c @@ -424,6 +424,27 @@ static void print_node_to_core_map(void) } } +static void pin_all_possible_cpus(void) +{ + int core_id, node_id, cpu; + static int initialized; + + if (initialized) + return; + print_node_to_core_map(); + node_id = 0; + for_each_possible_cpu(cpu) { + core_id = smp_get_base_cpu(cpu); + if (emu_cores->to_node_id[core_id] != NODE_ID_FREE) + continue; + pin_core_to_node(core_id, node_id); + cpu_topology[cpu].node_id = node_id; + node_id = (node_id + 1) % emu_nodes; + } + print_node_to_core_map(); + initialized = 1; +} + /* * Transfer physical topology into a NUMA topology and modify CPU masks * according to the NUMA topology. @@ -441,7 +462,7 @@ static void emu_update_cpu_topology(void) toptree_free(phys); toptree_to_topology(numa); toptree_free(numa); - print_node_to_core_map(); + pin_all_possible_cpus(); } /* -- cgit v1.2.3