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v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/threads.h>
 
  3#include <linux/cpumask.h>
  4#include <linux/string.h>
  5#include <linux/kernel.h>
  6#include <linux/ctype.h>
  7#include <linux/dmar.h>
  8#include <linux/irq.h>
  9#include <linux/cpu.h>
 10
 11#include <asm/smp.h>
 12#include "x2apic.h"
 13
 14struct cluster_mask {
 15	unsigned int	clusterid;
 16	int		node;
 17	struct cpumask	mask;
 18};
 19
 20static DEFINE_PER_CPU(u32, x86_cpu_to_logical_apicid);
 21static DEFINE_PER_CPU(cpumask_var_t, ipi_mask);
 22static DEFINE_PER_CPU(struct cluster_mask *, cluster_masks);
 23static struct cluster_mask *cluster_hotplug_mask;
 24
 25static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 26{
 27	return x2apic_enabled();
 28}
 29
 30static void x2apic_send_IPI(int cpu, int vector)
 31{
 32	u32 dest = per_cpu(x86_cpu_to_logical_apicid, cpu);
 33
 34	x2apic_wrmsr_fence();
 
 35	__x2apic_send_IPI_dest(dest, vector, APIC_DEST_LOGICAL);
 36}
 37
 38static void
 39__x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
 40{
 41	unsigned int cpu, clustercpu;
 42	struct cpumask *tmpmsk;
 43	unsigned long flags;
 44	u32 dest;
 45
 46	x2apic_wrmsr_fence();
 
 47	local_irq_save(flags);
 48
 49	tmpmsk = this_cpu_cpumask_var_ptr(ipi_mask);
 50	cpumask_copy(tmpmsk, mask);
 51	/* If IPI should not be sent to self, clear current CPU */
 52	if (apic_dest != APIC_DEST_ALLINC)
 53		cpumask_clear_cpu(smp_processor_id(), tmpmsk);
 54
 55	/* Collapse cpus in a cluster so a single IPI per cluster is sent */
 56	for_each_cpu(cpu, tmpmsk) {
 57		struct cluster_mask *cmsk = per_cpu(cluster_masks, cpu);
 58
 59		dest = 0;
 60		for_each_cpu_and(clustercpu, tmpmsk, &cmsk->mask)
 61			dest |= per_cpu(x86_cpu_to_logical_apicid, clustercpu);
 62
 63		if (!dest)
 64			continue;
 65
 66		__x2apic_send_IPI_dest(dest, vector, apic->dest_logical);
 67		/* Remove cluster CPUs from tmpmask */
 68		cpumask_andnot(tmpmsk, tmpmsk, &cmsk->mask);
 69	}
 70
 71	local_irq_restore(flags);
 72}
 73
 74static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
 75{
 76	__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
 77}
 78
 79static void
 80x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
 81{
 82	__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
 83}
 84
 85static void x2apic_send_IPI_allbutself(int vector)
 86{
 87	__x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLBUT);
 88}
 89
 90static void x2apic_send_IPI_all(int vector)
 91{
 92	__x2apic_send_IPI_mask(cpu_online_mask, vector, APIC_DEST_ALLINC);
 93}
 94
 95static u32 x2apic_calc_apicid(unsigned int cpu)
 96{
 97	return per_cpu(x86_cpu_to_logical_apicid, cpu);
 98}
 99
100static void init_x2apic_ldr(void)
101{
102	struct cluster_mask *cmsk = this_cpu_read(cluster_masks);
103	u32 cluster, apicid = apic_read(APIC_LDR);
104	unsigned int cpu;
105
106	this_cpu_write(x86_cpu_to_logical_apicid, apicid);
107
108	if (cmsk)
109		goto update;
110
111	cluster = apicid >> 16;
112	for_each_online_cpu(cpu) {
113		cmsk = per_cpu(cluster_masks, cpu);
114		/* Matching cluster found. Link and update it. */
115		if (cmsk && cmsk->clusterid == cluster)
116			goto update;
117	}
118	cmsk = cluster_hotplug_mask;
119	cmsk->clusterid = cluster;
120	cluster_hotplug_mask = NULL;
121update:
122	this_cpu_write(cluster_masks, cmsk);
123	cpumask_set_cpu(smp_processor_id(), &cmsk->mask);
124}
125
126static int alloc_clustermask(unsigned int cpu, int node)
127{
128	if (per_cpu(cluster_masks, cpu))
129		return 0;
130	/*
131	 * If a hotplug spare mask exists, check whether it's on the right
132	 * node. If not, free it and allocate a new one.
133	 */
134	if (cluster_hotplug_mask) {
135		if (cluster_hotplug_mask->node == node)
136			return 0;
137		kfree(cluster_hotplug_mask);
138	}
139
140	cluster_hotplug_mask = kzalloc_node(sizeof(*cluster_hotplug_mask),
141					    GFP_KERNEL, node);
142	if (!cluster_hotplug_mask)
143		return -ENOMEM;
144	cluster_hotplug_mask->node = node;
145	return 0;
146}
147
148static int x2apic_prepare_cpu(unsigned int cpu)
149{
150	if (alloc_clustermask(cpu, cpu_to_node(cpu)) < 0)
151		return -ENOMEM;
152	if (!zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL))
153		return -ENOMEM;
154	return 0;
155}
156
157static int x2apic_dead_cpu(unsigned int dead_cpu)
158{
159	struct cluster_mask *cmsk = per_cpu(cluster_masks, dead_cpu);
160
161	cpumask_clear_cpu(dead_cpu, &cmsk->mask);
 
162	free_cpumask_var(per_cpu(ipi_mask, dead_cpu));
163	return 0;
164}
165
166static int x2apic_cluster_probe(void)
167{
168	if (!x2apic_mode)
169		return 0;
170
171	if (cpuhp_setup_state(CPUHP_X2APIC_PREPARE, "x86/x2apic:prepare",
172			      x2apic_prepare_cpu, x2apic_dead_cpu) < 0) {
173		pr_err("Failed to register X2APIC_PREPARE\n");
174		return 0;
175	}
176	init_x2apic_ldr();
177	return 1;
178}
179
180static struct apic apic_x2apic_cluster __ro_after_init = {
181
182	.name				= "cluster x2apic",
183	.probe				= x2apic_cluster_probe,
184	.acpi_madt_oem_check		= x2apic_acpi_madt_oem_check,
185	.apic_id_valid			= x2apic_apic_id_valid,
186	.apic_id_registered		= x2apic_apic_id_registered,
187
188	.irq_delivery_mode		= dest_Fixed,
189	.irq_dest_mode			= 1, /* logical */
190
191	.disable_esr			= 0,
192	.dest_logical			= APIC_DEST_LOGICAL,
193	.check_apicid_used		= NULL,
194
 
195	.init_apic_ldr			= init_x2apic_ldr,
196
197	.ioapic_phys_id_map		= NULL,
198	.setup_apic_routing		= NULL,
199	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
200	.apicid_to_cpu_present		= NULL,
201	.check_phys_apicid_present	= default_check_phys_apicid_present,
202	.phys_pkg_id			= x2apic_phys_pkg_id,
203
204	.get_apic_id			= x2apic_get_apic_id,
205	.set_apic_id			= x2apic_set_apic_id,
206
207	.calc_dest_apicid		= x2apic_calc_apicid,
208
209	.send_IPI			= x2apic_send_IPI,
210	.send_IPI_mask			= x2apic_send_IPI_mask,
211	.send_IPI_mask_allbutself	= x2apic_send_IPI_mask_allbutself,
212	.send_IPI_allbutself		= x2apic_send_IPI_allbutself,
213	.send_IPI_all			= x2apic_send_IPI_all,
214	.send_IPI_self			= x2apic_send_IPI_self,
215
216	.inquire_remote_apic		= NULL,
217
218	.read				= native_apic_msr_read,
219	.write				= native_apic_msr_write,
220	.eoi_write			= native_apic_msr_eoi_write,
221	.icr_read			= native_x2apic_icr_read,
222	.icr_write			= native_x2apic_icr_write,
223	.wait_icr_idle			= native_x2apic_wait_icr_idle,
224	.safe_wait_icr_idle		= native_safe_x2apic_wait_icr_idle,
225};
226
227apic_driver(apic_x2apic_cluster);
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0
  2
  3#include <linux/cpuhotplug.h>
  4#include <linux/cpumask.h>
  5#include <linux/slab.h>
  6#include <linux/mm.h>
  7
  8#include <asm/apic.h>
 
 
  9
 10#include "local.h"
 
 11
 12struct cluster_mask {
 13	unsigned int	clusterid;
 14	int		node;
 15	struct cpumask	mask;
 16};
 17
 18static DEFINE_PER_CPU(u32, x86_cpu_to_logical_apicid);
 19static DEFINE_PER_CPU(cpumask_var_t, ipi_mask);
 20static DEFINE_PER_CPU(struct cluster_mask *, cluster_masks);
 21static struct cluster_mask *cluster_hotplug_mask;
 22
 23static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 24{
 25	return x2apic_enabled();
 26}
 27
 28static void x2apic_send_IPI(int cpu, int vector)
 29{
 30	u32 dest = per_cpu(x86_cpu_to_logical_apicid, cpu);
 31
 32	/* x2apic MSRs are special and need a special fence: */
 33	weak_wrmsr_fence();
 34	__x2apic_send_IPI_dest(dest, vector, APIC_DEST_LOGICAL);
 35}
 36
 37static void
 38__x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
 39{
 40	unsigned int cpu, clustercpu;
 41	struct cpumask *tmpmsk;
 42	unsigned long flags;
 43	u32 dest;
 44
 45	/* x2apic MSRs are special and need a special fence: */
 46	weak_wrmsr_fence();
 47	local_irq_save(flags);
 48
 49	tmpmsk = this_cpu_cpumask_var_ptr(ipi_mask);
 50	cpumask_copy(tmpmsk, mask);
 51	/* If IPI should not be sent to self, clear current CPU */
 52	if (apic_dest != APIC_DEST_ALLINC)
 53		__cpumask_clear_cpu(smp_processor_id(), tmpmsk);
 54
 55	/* Collapse cpus in a cluster so a single IPI per cluster is sent */
 56	for_each_cpu(cpu, tmpmsk) {
 57		struct cluster_mask *cmsk = per_cpu(cluster_masks, cpu);
 58
 59		dest = 0;
 60		for_each_cpu_and(clustercpu, tmpmsk, &cmsk->mask)
 61			dest |= per_cpu(x86_cpu_to_logical_apicid, clustercpu);
 62
 63		if (!dest)
 64			continue;
 65
 66		__x2apic_send_IPI_dest(dest, vector, APIC_DEST_LOGICAL);
 67		/* Remove cluster CPUs from tmpmask */
 68		cpumask_andnot(tmpmsk, tmpmsk, &cmsk->mask);
 69	}
 70
 71	local_irq_restore(flags);
 72}
 73
 74static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
 75{
 76	__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
 77}
 78
 79static void
 80x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
 81{
 82	__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
 83}
 84
 85static void x2apic_send_IPI_allbutself(int vector)
 86{
 87	__x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
 88}
 89
 90static void x2apic_send_IPI_all(int vector)
 91{
 92	__x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
 93}
 94
 95static u32 x2apic_calc_apicid(unsigned int cpu)
 96{
 97	return per_cpu(x86_cpu_to_logical_apicid, cpu);
 98}
 99
100static void init_x2apic_ldr(void)
101{
102	struct cluster_mask *cmsk = this_cpu_read(cluster_masks);
103	u32 cluster, apicid = apic_read(APIC_LDR);
104	unsigned int cpu;
105
106	this_cpu_write(x86_cpu_to_logical_apicid, apicid);
107
108	if (cmsk)
109		goto update;
110
111	cluster = apicid >> 16;
112	for_each_online_cpu(cpu) {
113		cmsk = per_cpu(cluster_masks, cpu);
114		/* Matching cluster found. Link and update it. */
115		if (cmsk && cmsk->clusterid == cluster)
116			goto update;
117	}
118	cmsk = cluster_hotplug_mask;
119	cmsk->clusterid = cluster;
120	cluster_hotplug_mask = NULL;
121update:
122	this_cpu_write(cluster_masks, cmsk);
123	cpumask_set_cpu(smp_processor_id(), &cmsk->mask);
124}
125
126static int alloc_clustermask(unsigned int cpu, int node)
127{
128	if (per_cpu(cluster_masks, cpu))
129		return 0;
130	/*
131	 * If a hotplug spare mask exists, check whether it's on the right
132	 * node. If not, free it and allocate a new one.
133	 */
134	if (cluster_hotplug_mask) {
135		if (cluster_hotplug_mask->node == node)
136			return 0;
137		kfree(cluster_hotplug_mask);
138	}
139
140	cluster_hotplug_mask = kzalloc_node(sizeof(*cluster_hotplug_mask),
141					    GFP_KERNEL, node);
142	if (!cluster_hotplug_mask)
143		return -ENOMEM;
144	cluster_hotplug_mask->node = node;
145	return 0;
146}
147
148static int x2apic_prepare_cpu(unsigned int cpu)
149{
150	if (alloc_clustermask(cpu, cpu_to_node(cpu)) < 0)
151		return -ENOMEM;
152	if (!zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL))
153		return -ENOMEM;
154	return 0;
155}
156
157static int x2apic_dead_cpu(unsigned int dead_cpu)
158{
159	struct cluster_mask *cmsk = per_cpu(cluster_masks, dead_cpu);
160
161	if (cmsk)
162		cpumask_clear_cpu(dead_cpu, &cmsk->mask);
163	free_cpumask_var(per_cpu(ipi_mask, dead_cpu));
164	return 0;
165}
166
167static int x2apic_cluster_probe(void)
168{
169	if (!x2apic_mode)
170		return 0;
171
172	if (cpuhp_setup_state(CPUHP_X2APIC_PREPARE, "x86/x2apic:prepare",
173			      x2apic_prepare_cpu, x2apic_dead_cpu) < 0) {
174		pr_err("Failed to register X2APIC_PREPARE\n");
175		return 0;
176	}
177	init_x2apic_ldr();
178	return 1;
179}
180
181static struct apic apic_x2apic_cluster __ro_after_init = {
182
183	.name				= "cluster x2apic",
184	.probe				= x2apic_cluster_probe,
185	.acpi_madt_oem_check		= x2apic_acpi_madt_oem_check,
186	.apic_id_valid			= x2apic_apic_id_valid,
187	.apic_id_registered		= x2apic_apic_id_registered,
188
189	.delivery_mode			= APIC_DELIVERY_MODE_FIXED,
190	.dest_mode_logical		= true,
191
192	.disable_esr			= 0,
 
 
193
194	.check_apicid_used		= NULL,
195	.init_apic_ldr			= init_x2apic_ldr,
 
196	.ioapic_phys_id_map		= NULL,
197	.setup_apic_routing		= NULL,
198	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
199	.apicid_to_cpu_present		= NULL,
200	.check_phys_apicid_present	= default_check_phys_apicid_present,
201	.phys_pkg_id			= x2apic_phys_pkg_id,
202
203	.get_apic_id			= x2apic_get_apic_id,
204	.set_apic_id			= x2apic_set_apic_id,
205
206	.calc_dest_apicid		= x2apic_calc_apicid,
207
208	.send_IPI			= x2apic_send_IPI,
209	.send_IPI_mask			= x2apic_send_IPI_mask,
210	.send_IPI_mask_allbutself	= x2apic_send_IPI_mask_allbutself,
211	.send_IPI_allbutself		= x2apic_send_IPI_allbutself,
212	.send_IPI_all			= x2apic_send_IPI_all,
213	.send_IPI_self			= x2apic_send_IPI_self,
214
215	.inquire_remote_apic		= NULL,
216
217	.read				= native_apic_msr_read,
218	.write				= native_apic_msr_write,
219	.eoi_write			= native_apic_msr_eoi_write,
220	.icr_read			= native_x2apic_icr_read,
221	.icr_write			= native_x2apic_icr_write,
222	.wait_icr_idle			= native_x2apic_wait_icr_idle,
223	.safe_wait_icr_idle		= native_safe_x2apic_wait_icr_idle,
224};
225
226apic_driver(apic_x2apic_cluster);