From fbc2010d92e595dc13d8048db2419f963c8cb25e Mon Sep 17 00:00:00 2001 From: Li Chen Date: Thu, 10 Jul 2025 18:57:09 +0800 Subject: [PATCH] x86/smpboot: moves x86_topology to static initialize and truncate The #ifdeffery and the initializers in build_sched_topology() are just disgusting. Statically initialize the domain levels in the topology array and let build_sched_topology() invalidate the package domain level when NUMA in package is available. Suggested-by: Thomas Gleixner Signed-off-by: Li Chen Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: K Prateek Nayak Tested-by: K Prateek Nayak Link: https://lore.kernel.org/r/20250710105715.66594-4-me@linux.beauty --- arch/x86/kernel/smpboot.c | 34 ++++++++++++++++------------------ 1 file changed, 16 insertions(+), 18 deletions(-) diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 30e6df2b4db6..8038286454cf 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -478,32 +478,30 @@ static int x86_cluster_flags(void) */ static bool x86_has_numa_in_package; -static struct sched_domain_topology_level x86_topology[6]; - -static void __init build_sched_topology(void) -{ - int i = 0; - - x86_topology[i++] = SDTL_INIT(cpu_smt_mask, cpu_smt_flags, SMT); +static struct sched_domain_topology_level x86_topology[] = { + SDTL_INIT(cpu_smt_mask, cpu_smt_flags, SMT), #ifdef CONFIG_SCHED_CLUSTER - x86_topology[i++] = SDTL_INIT(cpu_clustergroup_mask, x86_cluster_flags, CLS); + SDTL_INIT(cpu_clustergroup_mask, x86_cluster_flags, CLS), #endif #ifdef CONFIG_SCHED_MC - x86_topology[i++] = SDTL_INIT(cpu_coregroup_mask, x86_core_flags, MC); + SDTL_INIT(cpu_coregroup_mask, x86_core_flags, MC), #endif - /* - * When there is NUMA topology inside the package skip the PKG domain - * since the NUMA domains will auto-magically create the right spanning - * domains based on the SLIT. - */ - if (!x86_has_numa_in_package) - x86_topology[i++] = SDTL_INIT(cpu_cpu_mask, x86_sched_itmt_flags, PKG); + SDTL_INIT(cpu_cpu_mask, x86_sched_itmt_flags, PKG), + { NULL }, +}; +static void __init build_sched_topology(void) +{ /* - * There must be one trailing NULL entry left. + * When there is NUMA topology inside the package invalidate the + * PKG domain since the NUMA domains will auto-magically create the + * right spanning domains based on the SLIT. */ - BUG_ON(i >= ARRAY_SIZE(x86_topology) - 1); + if (x86_has_numa_in_package) { + unsigned int pkgdom = ARRAY_SIZE(x86_topology) - 2; + memset(&x86_topology[pkgdom], 0, sizeof(x86_topology[pkgdom])); + } set_sched_topology(x86_topology); } -- 2.47.2