blob: 5fac6919b957fa88a9b9cc130007671ffbc00d13 [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
Konrad Rzeszutek Wilked467e62011-09-01 09:48:27 -040035#include <xen/hvc-console.h>
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070036#include "xen-ops.h"
37#include "mmu.h"
38
Mike Travisb78936e2008-12-16 17:33:57 -080039cpumask_var_t xen_cpu_initialized_map;
Jens Axboe3b16cf82008-06-26 11:21:54 +020040
Tejun Heoc6e22f92009-10-29 22:34:13 +090041static DEFINE_PER_CPU(int, xen_resched_irq);
42static DEFINE_PER_CPU(int, xen_callfunc_irq);
43static DEFINE_PER_CPU(int, xen_callfuncsingle_irq);
44static DEFINE_PER_CPU(int, xen_debug_irq) = -1;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070045
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070046static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
Jens Axboe3b16cf82008-06-26 11:21:54 +020047static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070048
49/*
Peter Zijlstra184748c2011-04-05 17:23:39 +020050 * Reschedule call back.
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070051 */
52static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
53{
Brian Gerst1b437c82009-01-19 00:38:57 +090054 inc_irq_stat(irq_resched_count);
Peter Zijlstra184748c2011-04-05 17:23:39 +020055 scheduler_ipi();
Jeremy Fitzhardinge38bb5ab2008-05-26 23:31:16 +010056
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070057 return IRQ_HANDLED;
58}
59
Daniel Kiperb53cede2011-05-04 20:18:05 +020060static void __cpuinit cpu_bringup(void)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070061{
Srivatsa S. Bhate8c9e782012-03-22 18:29:24 +053062 int cpu;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070063
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
Konrad Rzeszutek Wilk106b4432012-03-21 13:03:45 -040078 notify_cpu_starting(cpu);
79
80 ipi_call_lock();
Rusty Russelld7d37562009-11-03 14:58:38 +103081 set_cpu_online(cpu, true);
Konrad Rzeszutek Wilk106b4432012-03-21 13:03:45 -040082 ipi_call_unlock();
83
Alex Shi2113f462012-01-13 23:53:35 +080084 this_cpu_write(cpu_state, CPU_ONLINE);
Konrad Rzeszutek Wilk106b4432012-03-21 13:03:45 -040085
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -070086 wmb();
87
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070088 /* We can take interrupts now: we're officially "up". */
89 local_irq_enable();
90
91 wmb(); /* make sure everything is out */
Alex Nixond68d82a2008-08-22 11:52:15 +010092}
93
Daniel Kiperb53cede2011-05-04 20:18:05 +020094static void __cpuinit cpu_bringup_and_idle(void)
Alex Nixond68d82a2008-08-22 11:52:15 +010095{
96 cpu_bringup();
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -070097 cpu_idle();
98}
99
100static int xen_smp_intr_init(unsigned int cpu)
101{
102 int rc;
Jeremy Fitzhardingeee523ca2008-03-17 16:37:18 -0700103 const char *resched_name, *callfunc_name, *debug_name;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700104
105 resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
106 rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
107 cpu,
108 xen_reschedule_interrupt,
109 IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
110 resched_name,
111 NULL);
112 if (rc < 0)
113 goto fail;
Tejun Heoc6e22f92009-10-29 22:34:13 +0900114 per_cpu(xen_resched_irq, cpu) = rc;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700115
116 callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
117 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
118 cpu,
119 xen_call_function_interrupt,
120 IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
121 callfunc_name,
122 NULL);
123 if (rc < 0)
124 goto fail;
Tejun Heoc6e22f92009-10-29 22:34:13 +0900125 per_cpu(xen_callfunc_irq, cpu) = rc;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700126
Jeremy Fitzhardingeee523ca2008-03-17 16:37:18 -0700127 debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
128 rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
129 IRQF_DISABLED | IRQF_PERCPU | IRQF_NOBALANCING,
130 debug_name, NULL);
131 if (rc < 0)
132 goto fail;
Tejun Heoc6e22f92009-10-29 22:34:13 +0900133 per_cpu(xen_debug_irq, cpu) = rc;
Jeremy Fitzhardingeee523ca2008-03-17 16:37:18 -0700134
Jens Axboe3b16cf82008-06-26 11:21:54 +0200135 callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
136 rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
137 cpu,
138 xen_call_function_single_interrupt,
139 IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
140 callfunc_name,
141 NULL);
142 if (rc < 0)
143 goto fail;
Tejun Heoc6e22f92009-10-29 22:34:13 +0900144 per_cpu(xen_callfuncsingle_irq, cpu) = rc;
Jens Axboe3b16cf82008-06-26 11:21:54 +0200145
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700146 return 0;
147
148 fail:
Tejun Heoc6e22f92009-10-29 22:34:13 +0900149 if (per_cpu(xen_resched_irq, cpu) >= 0)
150 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu), NULL);
151 if (per_cpu(xen_callfunc_irq, cpu) >= 0)
152 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
153 if (per_cpu(xen_debug_irq, cpu) >= 0)
154 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
155 if (per_cpu(xen_callfuncsingle_irq, cpu) >= 0)
156 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu),
157 NULL);
Jens Axboe3b16cf82008-06-26 11:21:54 +0200158
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700159 return rc;
160}
161
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700162static void __init xen_fill_possible_map(void)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700163{
164 int i, rc;
165
Stefano Stabelliniea5b8f72010-10-26 17:28:33 +0100166 if (xen_initial_domain())
167 return;
168
Mike Travise7986732008-12-16 17:33:52 -0800169 for (i = 0; i < nr_cpu_ids; i++) {
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700170 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
Jeremy Fitzhardinge4560a292008-07-08 15:06:56 -0700171 if (rc >= 0) {
172 num_processors++;
Rusty Russell4f062892009-03-13 14:49:54 +1030173 set_cpu_possible(i, true);
Jeremy Fitzhardinge4560a292008-07-08 15:06:56 -0700174 }
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700175 }
176}
177
Stefano Stabelliniea5b8f72010-10-26 17:28:33 +0100178static void __init xen_filter_cpu_maps(void)
179{
180 int i, rc;
181
182 if (!xen_initial_domain())
183 return;
184
Stefano Stabellini801fd142010-09-23 12:06:25 +0100185 num_processors = 0;
186 disabled_cpus = 0;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700187 for (i = 0; i < nr_cpu_ids; i++) {
188 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
189 if (rc >= 0) {
190 num_processors++;
191 set_cpu_possible(i, true);
Stefano Stabellini801fd142010-09-23 12:06:25 +0100192 } else {
193 set_cpu_possible(i, false);
194 set_cpu_present(i, false);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700195 }
196 }
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700197}
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700198
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700199static void __init xen_smp_prepare_boot_cpu(void)
200{
201 BUG_ON(smp_processor_id() != 0);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700202 native_smp_prepare_boot_cpu();
203
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700204 /* We've switched to the "real" per-cpu gdt, so make sure the
Jeremy Fitzhardinge60223a32007-07-17 18:37:07 -0700205 old memory can be recycled */
Jeremy Fitzhardinge38341432009-02-02 13:55:31 -0800206 make_lowmem_page_readwrite(xen_initial_gdt);
Jeremy Fitzhardinge60223a32007-07-17 18:37:07 -0700207
Stefano Stabelliniea5b8f72010-10-26 17:28:33 +0100208 xen_filter_cpu_maps();
Jeremy Fitzhardinge60223a32007-07-17 18:37:07 -0700209 xen_setup_vcpu_info_placement();
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700210}
211
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700212static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700213{
214 unsigned cpu;
Andrew Jones900cba82009-12-18 10:31:31 +0100215 unsigned int i;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700216
Konrad Rzeszutek Wilked467e62011-09-01 09:48:27 -0400217 if (skip_ioapic_setup) {
218 char *m = (max_cpus == 0) ?
219 "The nosmp parameter is incompatible with Xen; " \
220 "use Xen dom0_max_vcpus=1 parameter" :
221 "The noapic parameter is incompatible with Xen";
222
223 xen_raw_printk(m);
224 panic(m);
225 }
Jeremy Fitzhardinge2d9e1e22008-07-07 12:07:53 -0700226 xen_init_lock_cpu(0);
227
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700228 smp_store_cpu_info(0);
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700229 cpu_data(0).x86_max_cores = 1;
Andrew Jones900cba82009-12-18 10:31:31 +0100230
231 for_each_possible_cpu(i) {
232 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
233 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
234 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
235 }
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700236 set_cpu_sibling_map(0);
237
238 if (xen_smp_intr_init(0))
239 BUG();
240
Mike Travisb78936e2008-12-16 17:33:57 -0800241 if (!alloc_cpumask_var(&xen_cpu_initialized_map, GFP_KERNEL))
242 panic("could not allocate xen_cpu_initialized_map\n");
243
244 cpumask_copy(xen_cpu_initialized_map, cpumask_of(0));
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700245
246 /* Restrict the possible_map according to max_cpus. */
247 while ((num_possible_cpus() > 1) && (num_possible_cpus() > max_cpus)) {
Mike Travise7986732008-12-16 17:33:52 -0800248 for (cpu = nr_cpu_ids - 1; !cpu_possible(cpu); cpu--)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700249 continue;
Rusty Russell4f062892009-03-13 14:49:54 +1030250 set_cpu_possible(cpu, false);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700251 }
252
253 for_each_possible_cpu (cpu) {
254 struct task_struct *idle;
255
256 if (cpu == 0)
257 continue;
258
259 idle = fork_idle(cpu);
260 if (IS_ERR(idle))
261 panic("failed fork for CPU %d", cpu);
262
Rusty Russell4f062892009-03-13 14:49:54 +1030263 set_cpu_present(cpu, true);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700264 }
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700265}
266
Daniel Kiperb53cede2011-05-04 20:18:05 +0200267static int __cpuinit
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700268cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
269{
270 struct vcpu_guest_context *ctxt;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700271 struct desc_struct *gdt;
Jeremy Fitzhardinge9976b392009-02-27 09:19:26 -0800272 unsigned long gdt_mfn;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700273
Mike Travisb78936e2008-12-16 17:33:57 -0800274 if (cpumask_test_and_set_cpu(cpu, xen_cpu_initialized_map))
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700275 return 0;
276
277 ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
278 if (ctxt == NULL)
279 return -ENOMEM;
280
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700281 gdt = get_cpu_gdt_table(cpu);
282
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700283 ctxt->flags = VGCF_IN_KERNEL;
284 ctxt->user_regs.ds = __USER_DS;
285 ctxt->user_regs.es = __USER_DS;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700286 ctxt->user_regs.ss = __KERNEL_DS;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700287#ifdef CONFIG_X86_32
288 ctxt->user_regs.fs = __KERNEL_PERCPU;
Jeremy Fitzhardinge577eebe2009-08-27 12:46:35 -0700289 ctxt->user_regs.gs = __KERNEL_STACK_CANARY;
Jeremy Fitzhardinge795f99b2009-01-30 17:47:54 +0900290#else
291 ctxt->gs_base_kernel = per_cpu_offset(cpu);
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700292#endif
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700293 ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
294 ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
295
296 memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
297
298 xen_copy_trap_info(ctxt->trap_ctxt);
299
300 ctxt->ldt_ents = 0;
301
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700302 BUG_ON((unsigned long)gdt & ~PAGE_MASK);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700303
Jeremy Fitzhardinge9976b392009-02-27 09:19:26 -0800304 gdt_mfn = arbitrary_virt_to_mfn(gdt);
305 make_lowmem_page_readonly(gdt);
306 make_lowmem_page_readonly(mfn_to_virt(gdt_mfn));
307
308 ctxt->gdt_frames[0] = gdt_mfn;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700309 ctxt->gdt_ents = GDT_ENTRIES;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700310
311 ctxt->user_regs.cs = __KERNEL_CS;
H. Peter Anvinfaca6222008-01-30 13:31:02 +0100312 ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700313
314 ctxt->kernel_ss = __KERNEL_DS;
H. Peter Anvinfaca6222008-01-30 13:31:02 +0100315 ctxt->kernel_sp = idle->thread.sp0;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700316
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700317#ifdef CONFIG_X86_32
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700318 ctxt->event_callback_cs = __KERNEL_CS;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700319 ctxt->failsafe_callback_cs = __KERNEL_CS;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700320#endif
321 ctxt->event_callback_eip = (unsigned long)xen_hypervisor_callback;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700322 ctxt->failsafe_callback_eip = (unsigned long)xen_failsafe_callback;
323
324 per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir);
325 ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_mfn(swapper_pg_dir));
326
327 if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt))
328 BUG();
329
330 kfree(ctxt);
331 return 0;
332}
333
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700334static int __cpuinit xen_cpu_up(unsigned int cpu)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700335{
336 struct task_struct *idle = idle_task(cpu);
337 int rc;
338
Brian Gerstc6f5e0a2009-01-19 00:38:58 +0900339 per_cpu(current_task, cpu) = idle;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700340#ifdef CONFIG_X86_32
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700341 irq_ctx_init(cpu);
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700342#else
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700343 clear_tsk_thread_flag(idle, TIF_FORK);
Jeremy Fitzhardinge38341432009-02-02 13:55:31 -0800344 per_cpu(kernel_stack, cpu) =
345 (unsigned long)task_stack_page(idle) -
346 KERNEL_STACK_OFFSET + THREAD_SIZE;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700347#endif
Ian Campbell02889672009-11-24 09:32:48 -0800348 xen_setup_runstate_info(cpu);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700349 xen_setup_timer(cpu);
Jeremy Fitzhardinge2d9e1e22008-07-07 12:07:53 -0700350 xen_init_lock_cpu(cpu);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700351
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700352 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
353
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700354 /* make sure interrupts start blocked */
355 per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
356
357 rc = cpu_initialize_context(cpu, idle);
358 if (rc)
359 return rc;
360
361 if (num_online_cpus() == 1)
362 alternatives_smp_switch(1);
363
364 rc = xen_smp_intr_init(cpu);
365 if (rc)
366 return rc;
367
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700368 rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL);
369 BUG_ON(rc);
370
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700371 while(per_cpu(cpu_state, cpu) != CPU_ONLINE) {
Hannes Eder1207cf8e2009-03-05 20:13:57 +0100372 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700373 barrier();
374 }
375
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700376 return 0;
377}
378
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700379static void xen_smp_cpus_done(unsigned int max_cpus)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700380{
381}
382
Alex Nixon27371462008-09-08 13:43:33 +0100383#ifdef CONFIG_HOTPLUG_CPU
Alex Nixon26fd1052008-09-08 13:43:34 +0100384static int xen_cpu_disable(void)
Alex Nixond68d82a2008-08-22 11:52:15 +0100385{
386 unsigned int cpu = smp_processor_id();
387 if (cpu == 0)
388 return -EBUSY;
389
390 cpu_disable_common();
391
392 load_cr3(swapper_pg_dir);
393 return 0;
394}
395
Alex Nixon26fd1052008-09-08 13:43:34 +0100396static void xen_cpu_die(unsigned int cpu)
Alex Nixond68d82a2008-08-22 11:52:15 +0100397{
398 while (HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) {
399 current->state = TASK_UNINTERRUPTIBLE;
400 schedule_timeout(HZ/10);
401 }
Tejun Heoc6e22f92009-10-29 22:34:13 +0900402 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu), NULL);
403 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
404 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
405 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL);
Alex Nixond68d82a2008-08-22 11:52:15 +0100406 xen_uninit_lock_cpu(cpu);
407 xen_teardown_timer(cpu);
408
409 if (num_online_cpus() == 1)
410 alternatives_smp_switch(0);
411}
412
Robert P. J. Day71709242009-12-28 11:50:29 -0500413static void __cpuinit xen_play_dead(void) /* used only with HOTPLUG_CPU */
Alex Nixond68d82a2008-08-22 11:52:15 +0100414{
415 play_dead_common();
416 HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
417 cpu_bringup();
Konrad Rzeszutek Wilk41bd9562012-02-01 15:56:54 -0500418 /*
419 * Balance out the preempt calls - as we are running in cpu_idle
420 * loop which has been called at bootup from cpu_bringup_and_idle.
421 * The cpucpu_bringup_and_idle called cpu_bringup which made a
422 * preempt_disable() So this preempt_enable will balance it out.
423 */
424 preempt_enable();
Alex Nixond68d82a2008-08-22 11:52:15 +0100425}
426
Alex Nixon27371462008-09-08 13:43:33 +0100427#else /* !CONFIG_HOTPLUG_CPU */
Alex Nixon26fd1052008-09-08 13:43:34 +0100428static int xen_cpu_disable(void)
Alex Nixon27371462008-09-08 13:43:33 +0100429{
430 return -ENOSYS;
431}
432
Alex Nixon26fd1052008-09-08 13:43:34 +0100433static void xen_cpu_die(unsigned int cpu)
Alex Nixon27371462008-09-08 13:43:33 +0100434{
435 BUG();
436}
437
Alex Nixon26fd1052008-09-08 13:43:34 +0100438static void xen_play_dead(void)
Alex Nixon27371462008-09-08 13:43:33 +0100439{
440 BUG();
441}
442
443#endif
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700444static void stop_self(void *v)
445{
446 int cpu = smp_processor_id();
447
448 /* make sure we're not pinning something down */
449 load_cr3(swapper_pg_dir);
450 /* should set up a minimal gdt */
451
Ian Campbell086748e2010-08-03 14:55:14 -0700452 set_cpu_online(cpu, false);
453
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700454 HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
455 BUG();
456}
457
Alok Kataria76fac072010-10-11 14:37:08 -0700458static void xen_stop_other_cpus(int wait)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700459{
Alok Kataria76fac072010-10-11 14:37:08 -0700460 smp_call_function(stop_self, NULL, wait);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700461}
462
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700463static void xen_smp_send_reschedule(int cpu)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700464{
465 xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
466}
467
Mike Travisbcda0162008-12-16 17:33:59 -0800468static void xen_send_IPI_mask(const struct cpumask *mask,
469 enum ipi_vector vector)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700470{
471 unsigned cpu;
472
Mike Travisbcda0162008-12-16 17:33:59 -0800473 for_each_cpu_and(cpu, mask, cpu_online_mask)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700474 xen_send_IPI_one(cpu, vector);
475}
476
Mike Travisbcda0162008-12-16 17:33:59 -0800477static void xen_smp_send_call_function_ipi(const struct cpumask *mask)
Jens Axboe3b16cf82008-06-26 11:21:54 +0200478{
479 int cpu;
480
481 xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
482
483 /* Make sure other vcpus get a chance to run if they need to. */
Mike Travisbcda0162008-12-16 17:33:59 -0800484 for_each_cpu(cpu, mask) {
Jens Axboe3b16cf82008-06-26 11:21:54 +0200485 if (xen_vcpu_stolen(cpu)) {
Hannes Eder1207cf8e2009-03-05 20:13:57 +0100486 HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
Jens Axboe3b16cf82008-06-26 11:21:54 +0200487 break;
488 }
489 }
490}
491
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700492static void xen_smp_send_call_function_single_ipi(int cpu)
Jens Axboe3b16cf82008-06-26 11:21:54 +0200493{
Mike Travisbcda0162008-12-16 17:33:59 -0800494 xen_send_IPI_mask(cpumask_of(cpu),
Mike Travise7986732008-12-16 17:33:52 -0800495 XEN_CALL_FUNCTION_SINGLE_VECTOR);
Jens Axboe3b16cf82008-06-26 11:21:54 +0200496}
497
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700498static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
499{
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700500 irq_enter();
Jens Axboe3b16cf82008-06-26 11:21:54 +0200501 generic_smp_call_function_interrupt();
Brian Gerst1b437c82009-01-19 00:38:57 +0900502 inc_irq_stat(irq_call_count);
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700503 irq_exit();
504
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700505 return IRQ_HANDLED;
506}
507
Jens Axboe3b16cf82008-06-26 11:21:54 +0200508static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700509{
Jens Axboe3b16cf82008-06-26 11:21:54 +0200510 irq_enter();
511 generic_smp_call_function_single_interrupt();
Brian Gerst1b437c82009-01-19 00:38:57 +0900512 inc_irq_stat(irq_call_count);
Jens Axboe3b16cf82008-06-26 11:21:54 +0200513 irq_exit();
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700514
Jens Axboe3b16cf82008-06-26 11:21:54 +0200515 return IRQ_HANDLED;
Jeremy Fitzhardingef87e4ca2007-07-17 18:37:06 -0700516}
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700517
Daniel Kiperb53cede2011-05-04 20:18:05 +0200518static const struct smp_ops xen_smp_ops __initconst = {
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700519 .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
520 .smp_prepare_cpus = xen_smp_prepare_cpus,
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700521 .smp_cpus_done = xen_smp_cpus_done,
522
Alex Nixond68d82a2008-08-22 11:52:15 +0100523 .cpu_up = xen_cpu_up,
524 .cpu_die = xen_cpu_die,
525 .cpu_disable = xen_cpu_disable,
526 .play_dead = xen_play_dead,
527
Alok Kataria76fac072010-10-11 14:37:08 -0700528 .stop_other_cpus = xen_stop_other_cpus,
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700529 .smp_send_reschedule = xen_smp_send_reschedule,
530
531 .send_call_func_ipi = xen_smp_send_call_function_ipi,
532 .send_call_func_single_ipi = xen_smp_send_call_function_single_ipi,
533};
534
535void __init xen_smp_init(void)
536{
537 smp_ops = xen_smp_ops;
Jeremy Fitzhardingec7b75942008-07-08 15:06:43 -0700538 xen_fill_possible_map();
Jeremy Fitzhardinge2d9e1e22008-07-07 12:07:53 -0700539 xen_init_spinlocks();
Jeremy Fitzhardingea9e70622008-07-08 15:06:41 -0700540}
Stefano Stabellini99bbb3a2010-12-02 17:55:10 +0000541
542static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
543{
544 native_smp_prepare_cpus(max_cpus);
545 WARN_ON(xen_smp_intr_init(0));
546
Stefano Stabellini99bbb3a2010-12-02 17:55:10 +0000547 xen_init_lock_cpu(0);
Stefano Stabellini99bbb3a2010-12-02 17:55:10 +0000548}
549
550static int __cpuinit xen_hvm_cpu_up(unsigned int cpu)
551{
552 int rc;
553 rc = native_cpu_up(cpu);
554 WARN_ON (xen_smp_intr_init(cpu));
555 return rc;
556}
557
558static void xen_hvm_cpu_die(unsigned int cpu)
559{
560 unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu), NULL);
561 unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
562 unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
563 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL);
564 native_cpu_die(cpu);
565}
566
567void __init xen_hvm_smp_init(void)
568{
Stefano Stabellini3c05c4b2011-08-17 15:15:00 +0200569 if (!xen_have_vector_callback)
570 return;
Stefano Stabellini99bbb3a2010-12-02 17:55:10 +0000571 smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
572 smp_ops.smp_send_reschedule = xen_smp_send_reschedule;
573 smp_ops.cpu_up = xen_hvm_cpu_up;
574 smp_ops.cpu_die = xen_hvm_cpu_die;
575 smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
576 smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
577}