1 // SPDX-License-Identifier: GPL-2.0
17  * Using per cpu variable would cost one cache line per cpu.
29 static void x2apic_send_IPI(int cpu, int vector)  in x2apic_send_IPI()  argument
31 	u32 dest = x86_cpu_to_logical_apicid[cpu];  in x2apic_send_IPI()
41 	unsigned int cpu, clustercpu;  in __x2apic_send_IPI_mask()  local
52 	/* If IPI should not be sent to self, clear current CPU */  in __x2apic_send_IPI_mask()
56 	/* Collapse cpus in a cluster so a single IPI per cluster is sent */  in __x2apic_send_IPI_mask()
57 	for_each_cpu(cpu, tmpmsk) {  in __x2apic_send_IPI_mask()
58 		struct cpumask *cmsk = per_cpu(cluster_masks, cpu);  in __x2apic_send_IPI_mask()
68 		/* Remove cluster CPUs from tmpmask */  in __x2apic_send_IPI_mask()
86 static u32 x2apic_calc_apicid(unsigned int cpu)  in x2apic_calc_apicid()  argument
88 	return x86_cpu_to_logical_apicid[cpu];  in x2apic_calc_apicid()
105 static void prefill_clustermask(struct cpumask *cmsk, unsigned int cpu, u32 cluster)  in prefill_clustermask()  argument
111 		u32 apicid = apic->cpu_present_to_apicid(cpu_i);  in prefill_clustermask()
113 		if (apicid == BAD_APICID || cpu_i == cpu || apic_cluster(apicid) != cluster)  in prefill_clustermask()
124 static int alloc_clustermask(unsigned int cpu, u32 cluster, int node)  in alloc_clustermask()  argument
130 	 * At boot time, the CPU present mask is stable. The cluster mask is  in alloc_clustermask()
131 	 * allocated for the first CPU in the cluster and propagated to all  in alloc_clustermask()
132 	 * present siblings in the cluster. If the cluster mask is already set  in alloc_clustermask()
133 	 * on entry to this function for a given CPU, there is nothing to do.  in alloc_clustermask()
135 	if (per_cpu(cluster_masks, cpu))  in alloc_clustermask()
142 	 * On post boot hotplug for a CPU which was not present at boot time,  in alloc_clustermask()
144 	 * any more) to find any existing cluster mask.  in alloc_clustermask()
147 		u32 apicid = apic->cpu_present_to_apicid(cpu_i);  in alloc_clustermask()
149 		if (apicid != BAD_APICID && apic_cluster(apicid) == cluster) {  in alloc_clustermask()
152 			 * If the cluster is already initialized, just store  in alloc_clustermask()
156 				per_cpu(cluster_masks, cpu) = cmsk;  in alloc_clustermask()
162 	 * No CPU in the cluster has ever been initialized, so fall through to  in alloc_clustermask()
163 	 * the boot time code which will also populate the cluster mask for any  in alloc_clustermask()
164 	 * other CPU in the cluster which is (now) present.  in alloc_clustermask()
169 		return -ENOMEM;  in alloc_clustermask()
170 	per_cpu(cluster_masks, cpu) = cmsk;  in alloc_clustermask()
171 	prefill_clustermask(cmsk, cpu, cluster);  in alloc_clustermask()
176 static int x2apic_prepare_cpu(unsigned int cpu)  in x2apic_prepare_cpu()  argument
178 	u32 phys_apicid = apic->cpu_present_to_apicid(cpu);  in x2apic_prepare_cpu()
179 	u32 cluster = apic_cluster(phys_apicid);  in x2apic_prepare_cpu()  local
180 	u32 logical_apicid = (cluster << 16) | (1 << (phys_apicid & 0xf));  in x2apic_prepare_cpu()
181 	int node = cpu_to_node(cpu);  in x2apic_prepare_cpu()
183 	x86_cpu_to_logical_apicid[cpu] = logical_apicid;  in x2apic_prepare_cpu()
185 	if (alloc_clustermask(cpu, cluster, node) < 0)  in x2apic_prepare_cpu()
186 		return -ENOMEM;  in x2apic_prepare_cpu()
188 	if (!zalloc_cpumask_var_node(&per_cpu(ipi_mask, cpu), GFP_KERNEL, node))  in x2apic_prepare_cpu()
189 		return -ENOMEM;  in x2apic_prepare_cpu()
229 	.name				= "cluster x2apic",