blob: 834dfeb54e310b297b6f180a70deee67752b9f68 [file] [log] [blame]
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -07001/*
2 * Xen SMP support
3 *
4 * This file implements the Xen versions of smp_ops. SMP under Xen is
5 * very straightforward. Bringing a CPU up is simply a matter of
6 * loading its initial context and setting it running.
7 *
8 * IPIs are handled through the Xen event mechanism.
9 *
10 * Because virtual CPUs can be scheduled onto any real CPU, there's no
11 * useful topology information for the kernel to make use of. As a
12 * result, all CPUs are treated as if they're single-core and
13 * single-threaded.
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070014 */
15#include <linux/sched.h>
16#include <linux/err.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090017#include <linux/slab.h>
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070018#include <linux/smp.h>
19
20#include <asm/paravirt.h>
21#include <asm/desc.h>
22#include <asm/pgtable.h>
23#include <asm/cpu.h>
24
25#include <xen/interface/xen.h>
26#include <xen/interface/vcpu.h>
27
28#include <asm/xen/interface.h>
29#include <asm/xen/hypercall.h>
30
Stefano Stabelliniea5b8f72010-10-26 17:28:33 +010031#include <xen/xen.h>
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070032#include <xen/page.h>
33#include <xen/events.h>
34
35#include "xen-ops.h"
36#include "mmu.h"
37
Mike Travisb78936e2008-12-16 17:33:57 -080038cpumask_var_t xen_cpu_initialized_map;
Jens Axboe3b16cf82008-06-26 11:21:54 +020039
Tejun Heoc6e22f92009-10-29 22:34:13 +090040static DEFINE_PER_CPU(int, xen_resched_irq);
41static DEFINE_PER_CPU(int, xen_callfunc_irq);
42static DEFINE_PER_CPU(int, xen_callfuncsingle_irq);
43static DEFINE_PER_CPU(int, xen_debug_irq) = -1;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070044
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070045static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
Jens Axboe3b16cf82008-06-26 11:21:54 +020046static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070047
48/*
49 * Reschedule call back. Nothing to do,
50 * all the work is done automatically when
51 * we return from the interrupt.
52 */
53static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
54{
Brian Gerst1b437c82009-01-19 00:38:57 +090055 inc_irq_stat(irq_resched_count);
Jeremy Fitzhardinge38bb5ab2008-05-26 23:31:16 +010056
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070057 return IRQ_HANDLED;
58}
59
Alex Nixond68d82a2008-08-22 11:52:15 +010060static __cpuinit void cpu_bringup(void)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070061{
62 int cpu = smp_processor_id();
63
64 cpu_init();
Alex Nixond68d82a2008-08-22 11:52:15 +010065 touch_softlockup_watchdog();
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -070066 preempt_disable();
67
Jeremy Fitzhardingee2a81ba2008-03-17 16:37:17 -070068 xen_enable_sysenter();
Jeremy Fitzhardinge6fcac6d2008-07-08 15:07:14 -070069 xen_enable_syscall();
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070070
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -070071 cpu = smp_processor_id();
72 smp_store_cpu_info(cpu);
73 cpu_data(cpu).x86_max_cores = 1;
74 set_cpu_sibling_map(cpu);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070075
76 xen_setup_cpu_clockevents();
77
Rusty Russelld7d37562009-11-03 14:58:38 +103078 set_cpu_online(cpu, true);
Ingo Molnar6dbde352009-01-15 22:15:53 +090079 percpu_write(cpu_state, CPU_ONLINE);
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -070080 wmb();
81
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070082 /* We can take interrupts now: we're officially "up". */
83 local_irq_enable();
84
85 wmb(); /* make sure everything is out */
Alex Nixond68d82a2008-08-22 11:52:15 +010086}
87
88static __cpuinit void cpu_bringup_and_idle(void)
89{
90 cpu_bringup();
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070091 cpu_idle();
92}
93
94static int xen_smp_intr_init(unsigned int cpu)
95{
96 int rc;
Jeremy Fitzhardingeee523ca2008-03-17 16:37:18 -070097 const char *resched_name, *callfunc_name, *debug_name;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070098
99 resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
100 rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
101 cpu,
102 xen_reschedule_interrupt,
103 IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
104 resched_name,
105 NULL);
106 if (rc < 0)
107 goto fail;
Tejun Heoc6e22f92009-10-29 22:34:13 +0900108 per_cpu(xen_resched_irq, cpu) = rc;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700109
110 callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
111 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
112 cpu,
113 xen_call_function_interrupt,
114 IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
115 callfunc_name,
116 NULL);
117 if (rc < 0)
118 goto fail;
Tejun Heoc6e22f92009-10-29 22:34:13 +0900119 per_cpu(xen_callfunc_irq, cpu) = rc;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700120
Jeremy Fitzhardingeee523ca2008-03-17 16:37:18 -0700121 debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
122 rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
123 IRQF_DISABLED | IRQF_PERCPU | IRQF_NOBALANCING,
124 debug_name, NULL);
125 if (rc < 0)
126 goto fail;
Tejun Heoc6e22f92009-10-29 22:34:13 +0900127 per_cpu(xen_debug_irq, cpu) = rc;
Jeremy Fitzhardingeee523ca2008-03-17 16:37:18 -0700128
Jens Axboe3b16cf82008-06-26 11:21:54 +0200129 callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
130 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
131 cpu,
132 xen_call_function_single_interrupt,
133 IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
134 callfunc_name,
135 NULL);
136 if (rc < 0)
137 goto fail;
Tejun Heoc6e22f92009-10-29 22:34:13 +0900138 per_cpu(xen_callfuncsingle_irq, cpu) = rc;
Jens Axboe3b16cf82008-06-26 11:21:54 +0200139
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700140 return 0;
141
142 fail:
Tejun Heoc6e22f92009-10-29 22:34:13 +0900143 if (per_cpu(xen_resched_irq, cpu) >= 0)
144 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu), NULL);
145 if (per_cpu(xen_callfunc_irq, cpu) >= 0)
146 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
147 if (per_cpu(xen_debug_irq, cpu) >= 0)
148 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
149 if (per_cpu(xen_callfuncsingle_irq, cpu) >= 0)
150 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu),
151 NULL);
Jens Axboe3b16cf82008-06-26 11:21:54 +0200152
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700153 return rc;
154}
155
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700156static void __init xen_fill_possible_map(void)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700157{
158 int i, rc;
159
Stefano Stabelliniea5b8f72010-10-26 17:28:33 +0100160 if (xen_initial_domain())
161 return;
162
163 for (i = 0; i < nr_cpu_ids; i++) {
164 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
165 if (rc >= 0) {
166 num_processors++;
167 set_cpu_possible(i, true);
168 }
169 }
170}
171
172static void __init xen_filter_cpu_maps(void)
173{
174 int i, rc;
175
176 if (!xen_initial_domain())
177 return;
178
Stefano Stabellini801fd142010-09-23 12:06:25 +0100179 num_processors = 0;
180 disabled_cpus = 0;
Mike Travise7986732008-12-16 17:33:52 -0800181 for (i = 0; i < nr_cpu_ids; i++) {
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700182 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
Jeremy Fitzhardinge4560a292008-07-08 15:06:56 -0700183 if (rc >= 0) {
184 num_processors++;
Rusty Russell4f062892009-03-13 14:49:54 +1030185 set_cpu_possible(i, true);
Stefano Stabellini801fd142010-09-23 12:06:25 +0100186 } else {
187 set_cpu_possible(i, false);
188 set_cpu_present(i, false);
Jeremy Fitzhardinge4560a292008-07-08 15:06:56 -0700189 }
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700190 }
191}
192
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700193static void __init xen_smp_prepare_boot_cpu(void)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700194{
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700195 BUG_ON(smp_processor_id() != 0);
196 native_smp_prepare_boot_cpu();
197
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700198 /* We've switched to the "real" per-cpu gdt, so make sure the
199 old memory can be recycled */
Jeremy Fitzhardinge38341432009-02-02 13:55:31 -0800200 make_lowmem_page_readwrite(xen_initial_gdt);
Jeremy Fitzhardinge60223a32007-07-17 18:37:07 -0700201
Stefano Stabelliniea5b8f72010-10-26 17:28:33 +0100202 xen_filter_cpu_maps();
Jeremy Fitzhardinge60223a32007-07-17 18:37:07 -0700203 xen_setup_vcpu_info_placement();
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700204}
205
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700206static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700207{
208 unsigned cpu;
209
Jeremy Fitzhardinge2d9e1e22008-07-07 12:07:53 -0700210 xen_init_lock_cpu(0);
211
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700212 smp_store_cpu_info(0);
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700213 cpu_data(0).x86_max_cores = 1;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700214 set_cpu_sibling_map(0);
215
216 if (xen_smp_intr_init(0))
217 BUG();
218
Mike Travisb78936e2008-12-16 17:33:57 -0800219 if (!alloc_cpumask_var(&xen_cpu_initialized_map, GFP_KERNEL))
220 panic("could not allocate xen_cpu_initialized_map\n");
221
222 cpumask_copy(xen_cpu_initialized_map, cpumask_of(0));
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700223
224 /* Restrict the possible_map according to max_cpus. */
225 while ((num_possible_cpus() > 1) && (num_possible_cpus() > max_cpus)) {
Mike Travise7986732008-12-16 17:33:52 -0800226 for (cpu = nr_cpu_ids - 1; !cpu_possible(cpu); cpu--)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700227 continue;
Rusty Russell4f062892009-03-13 14:49:54 +1030228 set_cpu_possible(cpu, false);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700229 }
230
231 for_each_possible_cpu (cpu) {
232 struct task_struct *idle;
233
234 if (cpu == 0)
235 continue;
236
237 idle = fork_idle(cpu);
238 if (IS_ERR(idle))
239 panic("failed fork for CPU %d", cpu);
240
Rusty Russell4f062892009-03-13 14:49:54 +1030241 set_cpu_present(cpu, true);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700242 }
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700243}
244
245static __cpuinit int
246cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
247{
248 struct vcpu_guest_context *ctxt;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700249 struct desc_struct *gdt;
Jeremy Fitzhardinge9976b392009-02-27 09:19:26 -0800250 unsigned long gdt_mfn;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700251
Mike Travisb78936e2008-12-16 17:33:57 -0800252 if (cpumask_test_and_set_cpu(cpu, xen_cpu_initialized_map))
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700253 return 0;
254
255 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
256 if (ctxt == NULL)
257 return -ENOMEM;
258
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700259 gdt = get_cpu_gdt_table(cpu);
260
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700261 ctxt->flags = VGCF_IN_KERNEL;
262 ctxt->user_regs.ds = __USER_DS;
263 ctxt->user_regs.es = __USER_DS;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700264 ctxt->user_regs.ss = __KERNEL_DS;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700265#ifdef CONFIG_X86_32
266 ctxt->user_regs.fs = __KERNEL_PERCPU;
Jeremy Fitzhardinge577eebe2009-08-27 12:46:35 -0700267 ctxt->user_regs.gs = __KERNEL_STACK_CANARY;
Jeremy Fitzhardinge795f99b2009-01-30 17:47:54 +0900268#else
269 ctxt->gs_base_kernel = per_cpu_offset(cpu);
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700270#endif
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700271 ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
272 ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
273
274 memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
275
276 xen_copy_trap_info(ctxt->trap_ctxt);
277
278 ctxt->ldt_ents = 0;
279
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700280 BUG_ON((unsigned long)gdt & ~PAGE_MASK);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700281
Jeremy Fitzhardinge9976b392009-02-27 09:19:26 -0800282 gdt_mfn = arbitrary_virt_to_mfn(gdt);
283 make_lowmem_page_readonly(gdt);
284 make_lowmem_page_readonly(mfn_to_virt(gdt_mfn));
285
286 ctxt->gdt_frames[0] = gdt_mfn;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700287 ctxt->gdt_ents = GDT_ENTRIES;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700288
289 ctxt->user_regs.cs = __KERNEL_CS;
H. Peter Anvinfaca6222008-01-30 13:31:02 +0100290 ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700291
292 ctxt->kernel_ss = __KERNEL_DS;
H. Peter Anvinfaca6222008-01-30 13:31:02 +0100293 ctxt->kernel_sp = idle->thread.sp0;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700294
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700295#ifdef CONFIG_X86_32
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700296 ctxt->event_callback_cs = __KERNEL_CS;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700297 ctxt->failsafe_callback_cs = __KERNEL_CS;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700298#endif
299 ctxt->event_callback_eip = (unsigned long)xen_hypervisor_callback;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700300 ctxt->failsafe_callback_eip = (unsigned long)xen_failsafe_callback;
301
302 per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir);
303 ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_mfn(swapper_pg_dir));
304
305 if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt))
306 BUG();
307
308 kfree(ctxt);
309 return 0;
310}
311
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700312static int __cpuinit xen_cpu_up(unsigned int cpu)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700313{
314 struct task_struct *idle = idle_task(cpu);
315 int rc;
316
Brian Gerstc6f5e0a2009-01-19 00:38:58 +0900317 per_cpu(current_task, cpu) = idle;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700318#ifdef CONFIG_X86_32
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700319 irq_ctx_init(cpu);
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700320#else
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700321 clear_tsk_thread_flag(idle, TIF_FORK);
Jeremy Fitzhardinge38341432009-02-02 13:55:31 -0800322 per_cpu(kernel_stack, cpu) =
323 (unsigned long)task_stack_page(idle) -
324 KERNEL_STACK_OFFSET + THREAD_SIZE;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700325#endif
Ian Campbell02889672009-11-24 09:32:48 -0800326 xen_setup_runstate_info(cpu);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700327 xen_setup_timer(cpu);
Jeremy Fitzhardinge2d9e1e22008-07-07 12:07:53 -0700328 xen_init_lock_cpu(cpu);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700329
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700330 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
331
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700332 /* make sure interrupts start blocked */
333 per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
334
335 rc = cpu_initialize_context(cpu, idle);
336 if (rc)
337 return rc;
338
339 if (num_online_cpus() == 1)
340 alternatives_smp_switch(1);
341
342 rc = xen_smp_intr_init(cpu);
343 if (rc)
344 return rc;
345
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700346 rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL);
347 BUG_ON(rc);
348
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700349 while(per_cpu(cpu_state, cpu) != CPU_ONLINE) {
Hannes Eder1207cf8e2009-03-05 20:13:57 +0100350 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700351 barrier();
352 }
353
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700354 return 0;
355}
356
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700357static void xen_smp_cpus_done(unsigned int max_cpus)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700358{
359}
360
Alex Nixon27371462008-09-08 13:43:33 +0100361#ifdef CONFIG_HOTPLUG_CPU
Alex Nixon26fd1052008-09-08 13:43:34 +0100362static int xen_cpu_disable(void)
Alex Nixond68d82a2008-08-22 11:52:15 +0100363{
364 unsigned int cpu = smp_processor_id();
365 if (cpu == 0)
366 return -EBUSY;
367
368 cpu_disable_common();
369
370 load_cr3(swapper_pg_dir);
371 return 0;
372}
373
Alex Nixon26fd1052008-09-08 13:43:34 +0100374static void xen_cpu_die(unsigned int cpu)
Alex Nixond68d82a2008-08-22 11:52:15 +0100375{
376 while (HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) {
377 current->state = TASK_UNINTERRUPTIBLE;
378 schedule_timeout(HZ/10);
379 }
Tejun Heoc6e22f92009-10-29 22:34:13 +0900380 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu), NULL);
381 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
382 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
383 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL);
Alex Nixond68d82a2008-08-22 11:52:15 +0100384 xen_uninit_lock_cpu(cpu);
385 xen_teardown_timer(cpu);
386
387 if (num_online_cpus() == 1)
388 alternatives_smp_switch(0);
389}
390
Robert P. J. Day71709242009-12-28 11:50:29 -0500391static void __cpuinit xen_play_dead(void) /* used only with HOTPLUG_CPU */
Alex Nixond68d82a2008-08-22 11:52:15 +0100392{
393 play_dead_common();
394 HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
395 cpu_bringup();
396}
397
Alex Nixon27371462008-09-08 13:43:33 +0100398#else /* !CONFIG_HOTPLUG_CPU */
Alex Nixon26fd1052008-09-08 13:43:34 +0100399static int xen_cpu_disable(void)
Alex Nixon27371462008-09-08 13:43:33 +0100400{
401 return -ENOSYS;
402}
403
Alex Nixon26fd1052008-09-08 13:43:34 +0100404static void xen_cpu_die(unsigned int cpu)
Alex Nixon27371462008-09-08 13:43:33 +0100405{
406 BUG();
407}
408
Alex Nixon26fd1052008-09-08 13:43:34 +0100409static void xen_play_dead(void)
Alex Nixon27371462008-09-08 13:43:33 +0100410{
411 BUG();
412}
413
414#endif
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700415static void stop_self(void *v)
416{
417 int cpu = smp_processor_id();
418
419 /* make sure we're not pinning something down */
420 load_cr3(swapper_pg_dir);
421 /* should set up a minimal gdt */
422
Ian Campbell086748e2010-08-03 14:55:14 -0700423 set_cpu_online(cpu, false);
424
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700425 HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
426 BUG();
427}
428
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700429static void xen_smp_send_stop(void)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700430{
Jens Axboe8691e5a2008-06-06 11:18:06 +0200431 smp_call_function(stop_self, NULL, 0);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700432}
433
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700434static void xen_smp_send_reschedule(int cpu)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700435{
436 xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
437}
438
Mike Travisbcda0162008-12-16 17:33:59 -0800439static void xen_send_IPI_mask(const struct cpumask *mask,
440 enum ipi_vector vector)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700441{
442 unsigned cpu;
443
Mike Travisbcda0162008-12-16 17:33:59 -0800444 for_each_cpu_and(cpu, mask, cpu_online_mask)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700445 xen_send_IPI_one(cpu, vector);
446}
447
Mike Travisbcda0162008-12-16 17:33:59 -0800448static void xen_smp_send_call_function_ipi(const struct cpumask *mask)
Jens Axboe3b16cf82008-06-26 11:21:54 +0200449{
450 int cpu;
451
452 xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
453
454 /* Make sure other vcpus get a chance to run if they need to. */
Mike Travisbcda0162008-12-16 17:33:59 -0800455 for_each_cpu(cpu, mask) {
Jens Axboe3b16cf82008-06-26 11:21:54 +0200456 if (xen_vcpu_stolen(cpu)) {
Hannes Eder1207cf8e2009-03-05 20:13:57 +0100457 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
Jens Axboe3b16cf82008-06-26 11:21:54 +0200458 break;
459 }
460 }
461}
462
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700463static void xen_smp_send_call_function_single_ipi(int cpu)
Jens Axboe3b16cf82008-06-26 11:21:54 +0200464{
Mike Travisbcda0162008-12-16 17:33:59 -0800465 xen_send_IPI_mask(cpumask_of(cpu),
Mike Travise7986732008-12-16 17:33:52 -0800466 XEN_CALL_FUNCTION_SINGLE_VECTOR);
Jens Axboe3b16cf82008-06-26 11:21:54 +0200467}
468
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700469static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
470{
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700471 irq_enter();
Jens Axboe3b16cf82008-06-26 11:21:54 +0200472 generic_smp_call_function_interrupt();
Brian Gerst1b437c82009-01-19 00:38:57 +0900473 inc_irq_stat(irq_call_count);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700474 irq_exit();
475
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700476 return IRQ_HANDLED;
477}
478
Jens Axboe3b16cf82008-06-26 11:21:54 +0200479static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700480{
Jens Axboe3b16cf82008-06-26 11:21:54 +0200481 irq_enter();
482 generic_smp_call_function_single_interrupt();
Brian Gerst1b437c82009-01-19 00:38:57 +0900483 inc_irq_stat(irq_call_count);
Jens Axboe3b16cf82008-06-26 11:21:54 +0200484 irq_exit();
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700485
Jens Axboe3b16cf82008-06-26 11:21:54 +0200486 return IRQ_HANDLED;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700487}
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700488
489static const struct smp_ops xen_smp_ops __initdata = {
490 .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
491 .smp_prepare_cpus = xen_smp_prepare_cpus,
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700492 .smp_cpus_done = xen_smp_cpus_done,
493
Alex Nixond68d82a2008-08-22 11:52:15 +0100494 .cpu_up = xen_cpu_up,
495 .cpu_die = xen_cpu_die,
496 .cpu_disable = xen_cpu_disable,
497 .play_dead = xen_play_dead,
498
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700499 .smp_send_stop = xen_smp_send_stop,
500 .smp_send_reschedule = xen_smp_send_reschedule,
501
502 .send_call_func_ipi = xen_smp_send_call_function_ipi,
503 .send_call_func_single_ipi = xen_smp_send_call_function_single_ipi,
504};
505
506void __init xen_smp_init(void)
507{
508 smp_ops = xen_smp_ops;
Stefano Stabelliniea5b8f72010-10-26 17:28:33 +0100509 xen_fill_possible_map();
Jeremy Fitzhardinge2d9e1e22008-07-07 12:07:53 -0700510 xen_init_spinlocks();
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700511}