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v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/cpumask.h>
  3#include <linux/interrupt.h>
 
  4
  5#include <linux/mm.h>
  6#include <linux/delay.h>
  7#include <linux/spinlock.h>
  8#include <linux/kernel_stat.h>
  9#include <linux/mc146818rtc.h>
 10#include <linux/cache.h>
 11#include <linux/cpu.h>
 
 12
 13#include <asm/smp.h>
 14#include <asm/mtrr.h>
 15#include <asm/tlbflush.h>
 16#include <asm/mmu_context.h>
 17#include <asm/apic.h>
 18#include <asm/proto.h>
 19#include <asm/ipi.h>
 20
 21void __default_send_IPI_shortcut(unsigned int shortcut, int vector, unsigned int dest)
 22{
 23	/*
 24	 * Subtle. In the case of the 'never do double writes' workaround
 25	 * we have to lock out interrupts to be safe.  As we don't care
 26	 * of the value read we use an atomic rmw access to avoid costly
 27	 * cli/sti.  Otherwise we use an even cheaper single atomic write
 28	 * to the APIC.
 29	 */
 30	unsigned int cfg;
 31
 32	/*
 33	 * Wait for idle.
 34	 */
 35	__xapic_wait_icr_idle();
 36
 37	/*
 38	 * No need to touch the target chip field
 39	 */
 40	cfg = __prepare_ICR(shortcut, vector, dest);
 41
 42	/*
 43	 * Send the IPI. The write to APIC_ICR fires this off.
 44	 */
 45	native_apic_mem_write(APIC_ICR, cfg);
 46}
 47
 48/*
 49 * This is used to send an IPI with no shorthand notation (the destination is
 50 * specified in bits 56 to 63 of the ICR).
 51 */
 52void __default_send_IPI_dest_field(unsigned int mask, int vector, unsigned int dest)
 53{
 54	unsigned long cfg;
 55
 56	/*
 57	 * Wait for idle.
 58	 */
 59	if (unlikely(vector == NMI_VECTOR))
 60		safe_apic_wait_icr_idle();
 61	else
 62		__xapic_wait_icr_idle();
 63
 64	/*
 65	 * prepare target chip field
 66	 */
 67	cfg = __prepare_ICR2(mask);
 68	native_apic_mem_write(APIC_ICR2, cfg);
 69
 70	/*
 71	 * program the ICR
 72	 */
 73	cfg = __prepare_ICR(0, vector, dest);
 74
 75	/*
 76	 * Send the IPI. The write to APIC_ICR fires this off.
 77	 */
 78	native_apic_mem_write(APIC_ICR, cfg);
 79}
 80
 81void default_send_IPI_single_phys(int cpu, int vector)
 82{
 83	unsigned long flags;
 84
 85	local_irq_save(flags);
 86	__default_send_IPI_dest_field(per_cpu(x86_cpu_to_apicid, cpu),
 87				      vector, APIC_DEST_PHYSICAL);
 88	local_irq_restore(flags);
 89}
 90
 91void default_send_IPI_mask_sequence_phys(const struct cpumask *mask, int vector)
 92{
 93	unsigned long query_cpu;
 94	unsigned long flags;
 95
 96	/*
 97	 * Hack. The clustered APIC addressing mode doesn't allow us to send
 98	 * to an arbitrary mask, so I do a unicast to each CPU instead.
 99	 * - mbligh
100	 */
101	local_irq_save(flags);
102	for_each_cpu(query_cpu, mask) {
103		__default_send_IPI_dest_field(per_cpu(x86_cpu_to_apicid,
104				query_cpu), vector, APIC_DEST_PHYSICAL);
105	}
106	local_irq_restore(flags);
107}
108
109void default_send_IPI_mask_allbutself_phys(const struct cpumask *mask,
110						 int vector)
111{
112	unsigned int this_cpu = smp_processor_id();
113	unsigned int query_cpu;
114	unsigned long flags;
115
116	/* See Hack comment above */
117
118	local_irq_save(flags);
119	for_each_cpu(query_cpu, mask) {
120		if (query_cpu == this_cpu)
121			continue;
122		__default_send_IPI_dest_field(per_cpu(x86_cpu_to_apicid,
123				 query_cpu), vector, APIC_DEST_PHYSICAL);
124	}
125	local_irq_restore(flags);
126}
127
128/*
129 * Helper function for APICs which insist on cpumasks
130 */
131void default_send_IPI_single(int cpu, int vector)
132{
133	apic->send_IPI_mask(cpumask_of(cpu), vector);
134}
135
136#ifdef CONFIG_X86_32
137
138void default_send_IPI_mask_sequence_logical(const struct cpumask *mask,
139						 int vector)
140{
141	unsigned long flags;
142	unsigned int query_cpu;
143
144	/*
145	 * Hack. The clustered APIC addressing mode doesn't allow us to send
146	 * to an arbitrary mask, so I do a unicasts to each CPU instead. This
147	 * should be modified to do 1 message per cluster ID - mbligh
148	 */
149
150	local_irq_save(flags);
151	for_each_cpu(query_cpu, mask)
152		__default_send_IPI_dest_field(
153			early_per_cpu(x86_cpu_to_logical_apicid, query_cpu),
154			vector, apic->dest_logical);
155	local_irq_restore(flags);
156}
157
158void default_send_IPI_mask_allbutself_logical(const struct cpumask *mask,
159						 int vector)
160{
161	unsigned long flags;
162	unsigned int query_cpu;
163	unsigned int this_cpu = smp_processor_id();
164
165	/* See Hack comment above */
166
167	local_irq_save(flags);
168	for_each_cpu(query_cpu, mask) {
169		if (query_cpu == this_cpu)
170			continue;
171		__default_send_IPI_dest_field(
172			early_per_cpu(x86_cpu_to_logical_apicid, query_cpu),
173			vector, apic->dest_logical);
174		}
175	local_irq_restore(flags);
176}
177
178/*
179 * This is only used on smaller machines.
180 */
181void default_send_IPI_mask_logical(const struct cpumask *cpumask, int vector)
182{
183	unsigned long mask = cpumask_bits(cpumask)[0];
184	unsigned long flags;
185
186	if (!mask)
187		return;
188
189	local_irq_save(flags);
190	WARN_ON(mask & ~cpumask_bits(cpu_online_mask)[0]);
191	__default_send_IPI_dest_field(mask, vector, apic->dest_logical);
192	local_irq_restore(flags);
193}
194
195void default_send_IPI_allbutself(int vector)
196{
197	/*
198	 * if there are no other CPUs in the system then we get an APIC send
199	 * error if we try to broadcast, thus avoid sending IPIs in this case.
200	 */
201	if (!(num_online_cpus() > 1))
202		return;
203
204	__default_local_send_IPI_allbutself(vector);
205}
206
207void default_send_IPI_all(int vector)
208{
209	__default_local_send_IPI_all(vector);
210}
211
212void default_send_IPI_self(int vector)
213{
214	__default_send_IPI_shortcut(APIC_DEST_SELF, vector, apic->dest_logical);
215}
216
217/* must come after the send_IPI functions above for inlining */
218static int convert_apicid_to_cpu(int apic_id)
219{
220	int i;
221
222	for_each_possible_cpu(i) {
223		if (per_cpu(x86_cpu_to_apicid, i) == apic_id)
224			return i;
225	}
226	return -1;
227}
228
229int safe_smp_processor_id(void)
230{
231	int apicid, cpuid;
232
233	if (!boot_cpu_has(X86_FEATURE_APIC))
234		return 0;
235
236	apicid = hard_smp_processor_id();
237	if (apicid == BAD_APICID)
238		return 0;
239
240	cpuid = convert_apicid_to_cpu(apicid);
241
242	return cpuid >= 0 ? cpuid : 0;
243}
244#endif
v3.1
 
  1#include <linux/cpumask.h>
  2#include <linux/interrupt.h>
  3#include <linux/init.h>
  4
  5#include <linux/mm.h>
  6#include <linux/delay.h>
  7#include <linux/spinlock.h>
  8#include <linux/kernel_stat.h>
  9#include <linux/mc146818rtc.h>
 10#include <linux/cache.h>
 11#include <linux/cpu.h>
 12#include <linux/module.h>
 13
 14#include <asm/smp.h>
 15#include <asm/mtrr.h>
 16#include <asm/tlbflush.h>
 17#include <asm/mmu_context.h>
 18#include <asm/apic.h>
 19#include <asm/proto.h>
 20#include <asm/ipi.h>
 21
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 22void default_send_IPI_mask_sequence_phys(const struct cpumask *mask, int vector)
 23{
 24	unsigned long query_cpu;
 25	unsigned long flags;
 26
 27	/*
 28	 * Hack. The clustered APIC addressing mode doesn't allow us to send
 29	 * to an arbitrary mask, so I do a unicast to each CPU instead.
 30	 * - mbligh
 31	 */
 32	local_irq_save(flags);
 33	for_each_cpu(query_cpu, mask) {
 34		__default_send_IPI_dest_field(per_cpu(x86_cpu_to_apicid,
 35				query_cpu), vector, APIC_DEST_PHYSICAL);
 36	}
 37	local_irq_restore(flags);
 38}
 39
 40void default_send_IPI_mask_allbutself_phys(const struct cpumask *mask,
 41						 int vector)
 42{
 43	unsigned int this_cpu = smp_processor_id();
 44	unsigned int query_cpu;
 45	unsigned long flags;
 46
 47	/* See Hack comment above */
 48
 49	local_irq_save(flags);
 50	for_each_cpu(query_cpu, mask) {
 51		if (query_cpu == this_cpu)
 52			continue;
 53		__default_send_IPI_dest_field(per_cpu(x86_cpu_to_apicid,
 54				 query_cpu), vector, APIC_DEST_PHYSICAL);
 55	}
 56	local_irq_restore(flags);
 57}
 58
 
 
 
 
 
 
 
 
 59#ifdef CONFIG_X86_32
 60
 61void default_send_IPI_mask_sequence_logical(const struct cpumask *mask,
 62						 int vector)
 63{
 64	unsigned long flags;
 65	unsigned int query_cpu;
 66
 67	/*
 68	 * Hack. The clustered APIC addressing mode doesn't allow us to send
 69	 * to an arbitrary mask, so I do a unicasts to each CPU instead. This
 70	 * should be modified to do 1 message per cluster ID - mbligh
 71	 */
 72
 73	local_irq_save(flags);
 74	for_each_cpu(query_cpu, mask)
 75		__default_send_IPI_dest_field(
 76			early_per_cpu(x86_cpu_to_logical_apicid, query_cpu),
 77			vector, apic->dest_logical);
 78	local_irq_restore(flags);
 79}
 80
 81void default_send_IPI_mask_allbutself_logical(const struct cpumask *mask,
 82						 int vector)
 83{
 84	unsigned long flags;
 85	unsigned int query_cpu;
 86	unsigned int this_cpu = smp_processor_id();
 87
 88	/* See Hack comment above */
 89
 90	local_irq_save(flags);
 91	for_each_cpu(query_cpu, mask) {
 92		if (query_cpu == this_cpu)
 93			continue;
 94		__default_send_IPI_dest_field(
 95			early_per_cpu(x86_cpu_to_logical_apicid, query_cpu),
 96			vector, apic->dest_logical);
 97		}
 98	local_irq_restore(flags);
 99}
100
101/*
102 * This is only used on smaller machines.
103 */
104void default_send_IPI_mask_logical(const struct cpumask *cpumask, int vector)
105{
106	unsigned long mask = cpumask_bits(cpumask)[0];
107	unsigned long flags;
108
109	if (WARN_ONCE(!mask, "empty IPI mask"))
110		return;
111
112	local_irq_save(flags);
113	WARN_ON(mask & ~cpumask_bits(cpu_online_mask)[0]);
114	__default_send_IPI_dest_field(mask, vector, apic->dest_logical);
115	local_irq_restore(flags);
116}
117
118void default_send_IPI_allbutself(int vector)
119{
120	/*
121	 * if there are no other CPUs in the system then we get an APIC send
122	 * error if we try to broadcast, thus avoid sending IPIs in this case.
123	 */
124	if (!(num_online_cpus() > 1))
125		return;
126
127	__default_local_send_IPI_allbutself(vector);
128}
129
130void default_send_IPI_all(int vector)
131{
132	__default_local_send_IPI_all(vector);
133}
134
135void default_send_IPI_self(int vector)
136{
137	__default_send_IPI_shortcut(APIC_DEST_SELF, vector, apic->dest_logical);
138}
139
140/* must come after the send_IPI functions above for inlining */
141static int convert_apicid_to_cpu(int apic_id)
142{
143	int i;
144
145	for_each_possible_cpu(i) {
146		if (per_cpu(x86_cpu_to_apicid, i) == apic_id)
147			return i;
148	}
149	return -1;
150}
151
152int safe_smp_processor_id(void)
153{
154	int apicid, cpuid;
155
156	if (!cpu_has_apic)
157		return 0;
158
159	apicid = hard_smp_processor_id();
160	if (apicid == BAD_APICID)
161		return 0;
162
163	cpuid = convert_apicid_to_cpu(apicid);
164
165	return cpuid >= 0 ? cpuid : 0;
166}
167#endif