[linux-block.git] / arch / x86 / xen / smp.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/smp.h>
#include <linux/cpu.h>
#include <linux/slab.h>
#include <linux/cpumask.h>
#include <linux/percpu.h>

#include <xen/events.h>

#include <xen/hvc-console.h>
#include "xen-ops.h"
#include "smp.h"

static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 };
static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 };
static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 };
static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 };

static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);

/*
 * Reschedule call back.
 */
static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
{
	inc_irq_stat(irq_resched_count);
	scheduler_ipi();

	return IRQ_HANDLED;
}

void xen_smp_intr_free(unsigned int cpu)
{
	if (per_cpu(xen_resched_irq, cpu).irq >= 0) {
		unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL);
		per_cpu(xen_resched_irq, cpu).irq = -1;
		kfree(per_cpu(xen_resched_irq, cpu).name);
		per_cpu(xen_resched_irq, cpu).name = NULL;
	}
	if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) {
		unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL);
		per_cpu(xen_callfunc_irq, cpu).irq = -1;
		kfree(per_cpu(xen_callfunc_irq, cpu).name);
		per_cpu(xen_callfunc_irq, cpu).name = NULL;
	}
	if (per_cpu(xen_debug_irq, cpu).irq >= 0) {
		unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL);
		per_cpu(xen_debug_irq, cpu).irq = -1;
		kfree(per_cpu(xen_debug_irq, cpu).name);
		per_cpu(xen_debug_irq, cpu).name = NULL;
	}
	if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) {
		unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq,
				       NULL);
		per_cpu(xen_callfuncsingle_irq, cpu).irq = -1;
		kfree(per_cpu(xen_callfuncsingle_irq, cpu).name);
		per_cpu(xen_callfuncsingle_irq, cpu).name = NULL;
	}
}

int xen_smp_intr_init(unsigned int cpu)
{
	int rc;
	char *resched_name, *callfunc_name, *debug_name;

	resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
	rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
				    cpu,
				    xen_reschedule_interrupt,
				    IRQF_PERCPU|IRQF_NOBALANCING,
				    resched_name,
				    NULL);
	if (rc < 0)
		goto fail;
	per_cpu(xen_resched_irq, cpu).irq = rc;
	per_cpu(xen_resched_irq, cpu).name = resched_name;

	callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
	rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
				    cpu,
				    xen_call_function_interrupt,
				    IRQF_PERCPU|IRQF_NOBALANCING,
				    callfunc_name,
				    NULL);
	if (rc < 0)
		goto fail;
	per_cpu(xen_callfunc_irq, cpu).irq = rc;
	per_cpu(xen_callfunc_irq, cpu).name = callfunc_name;

	debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
	rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
				     IRQF_PERCPU | IRQF_NOBALANCING,
				     debug_name, NULL);
	if (rc < 0)
		goto fail;
	per_cpu(xen_debug_irq, cpu).irq = rc;
	per_cpu(xen_debug_irq, cpu).name = debug_name;

	callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
	rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
				    cpu,
				    xen_call_function_single_interrupt,
				    IRQF_PERCPU|IRQF_NOBALANCING,
				    callfunc_name,
				    NULL);
	if (rc < 0)
		goto fail;
	per_cpu(xen_callfuncsingle_irq, cpu).irq = rc;
	per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name;

	return 0;

 fail:
	xen_smp_intr_free(cpu);
	return rc;
}

void __init xen_smp_cpus_done(unsigned int max_cpus)
{
	int cpu, rc, count = 0;

	if (xen_hvm_domain())
		native_smp_cpus_done(max_cpus);

	if (xen_have_vcpu_info_placement)
		return;

	for_each_online_cpu(cpu) {
		if (xen_vcpu_nr(cpu) < MAX_VIRT_CPUS)
			continue;

		rc = cpu_down(cpu);

		if (rc == 0) {
			/*
			 * Reset vcpu_info so this cpu cannot be onlined again.
			 */
			xen_vcpu_info_reset(cpu);
			count++;
		} else {
			pr_warn("%s: failed to bring CPU %d down, error %d\n",
				__func__, cpu, rc);
		}
	}
	WARN(count, "%s: brought %d CPUs offline\n", __func__, count);
}

void xen_smp_send_reschedule(int cpu)
{
	xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
}

static void __xen_send_IPI_mask(const struct cpumask *mask,
			      int vector)
{
	unsigned cpu;

	for_each_cpu_and(cpu, mask, cpu_online_mask)
		xen_send_IPI_one(cpu, vector);
}

void xen_smp_send_call_function_ipi(const struct cpumask *mask)
{
	int cpu;

	__xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);

	/* Make sure other vcpus get a chance to run if they need to. */
	for_each_cpu(cpu, mask) {
		if (xen_vcpu_stolen(cpu)) {
			HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
			break;
		}
	}
}

void xen_smp_send_call_function_single_ipi(int cpu)
{
	__xen_send_IPI_mask(cpumask_of(cpu),
			  XEN_CALL_FUNCTION_SINGLE_VECTOR);
}

static inline int xen_map_vector(int vector)
{
	int xen_vector;

	switch (vector) {
	case RESCHEDULE_VECTOR:
		xen_vector = XEN_RESCHEDULE_VECTOR;
		break;
	case CALL_FUNCTION_VECTOR:
		xen_vector = XEN_CALL_FUNCTION_VECTOR;
		break;
	case CALL_FUNCTION_SINGLE_VECTOR:
		xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
		break;
	case IRQ_WORK_VECTOR:
		xen_vector = XEN_IRQ_WORK_VECTOR;
		break;
#ifdef CONFIG_X86_64
	case NMI_VECTOR:
	case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */
		xen_vector = XEN_NMI_VECTOR;
		break;
#endif
	default:
		xen_vector = -1;
		printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
			vector);
	}

	return xen_vector;
}

void xen_send_IPI_mask(const struct cpumask *mask,
			      int vector)
{
	int xen_vector = xen_map_vector(vector);

	if (xen_vector >= 0)
		__xen_send_IPI_mask(mask, xen_vector);
}

void xen_send_IPI_all(int vector)
{
	int xen_vector = xen_map_vector(vector);

	if (xen_vector >= 0)
		__xen_send_IPI_mask(cpu_online_mask, xen_vector);
}

void xen_send_IPI_self(int vector)
{
	int xen_vector = xen_map_vector(vector);

	if (xen_vector >= 0)
		xen_send_IPI_one(smp_processor_id(), xen_vector);
}

void xen_send_IPI_mask_allbutself(const struct cpumask *mask,
				int vector)
{
	unsigned cpu;
	unsigned int this_cpu = smp_processor_id();
	int xen_vector = xen_map_vector(vector);

	if (!(num_online_cpus() > 1) || (xen_vector < 0))
		return;

	for_each_cpu_and(cpu, mask, cpu_online_mask) {
		if (this_cpu == cpu)
			continue;

		xen_send_IPI_one(cpu, xen_vector);
	}
}

void xen_send_IPI_allbutself(int vector)
{
	xen_send_IPI_mask_allbutself(cpu_online_mask, vector);
}

static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
{
	irq_enter();
	generic_smp_call_function_interrupt();
	inc_irq_stat(irq_call_count);
	irq_exit();

	return IRQ_HANDLED;
}

static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
{
	irq_enter();
	generic_smp_call_function_single_interrupt();
	inc_irq_stat(irq_call_count);
	irq_exit();

	return IRQ_HANDLED;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
f87e4cac	2	#include <linux/smp.h>
ae039001	3	#include <linux/cpu.h>
83b96794 VK	4	#include <linux/slab.h>
	5	#include <linux/cpumask.h>
	6	#include <linux/percpu.h>
f87e4cac	7
f87e4cac JF	8	#include <xen/events.h>
f87e4cac JF	9
ed467e69	10	#include <xen/hvc-console.h>
f87e4cac	11	#include "xen-ops.h"
a2ef5dc2	12	#include "smp.h"
f87e4cac	13
ee336e10 KRW	14	static DEFINE_PER_CPU(struct xen_common_irq, xen_resched_irq) = { .irq = -1 };
	15	static DEFINE_PER_CPU(struct xen_common_irq, xen_callfunc_irq) = { .irq = -1 };
	16	static DEFINE_PER_CPU(struct xen_common_irq, xen_callfuncsingle_irq) = { .irq = -1 };
9547689f	17	static DEFINE_PER_CPU(struct xen_common_irq, xen_debug_irq) = { .irq = -1 };
f87e4cac JF	18
f87e4cac JF	19	static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
3b16cf87	20	static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
f87e4cac JF	21
f87e4cac JF	22	/*
184748cc	23	* Reschedule call back.
f87e4cac JF	24	*/
	25	static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
	26	{
1b437c8c	27	inc_irq_stat(irq_resched_count);
184748cc	28	scheduler_ipi();
38bb5ab4	29
f87e4cac JF	30	return IRQ_HANDLED;
	31	}
	32
5fc509bc	33	void xen_smp_intr_free(unsigned int cpu)
53b94fdc	34	{
ee336e10	35	if (per_cpu(xen_resched_irq, cpu).irq >= 0) {
9547689f	36	unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu).irq, NULL);
ee336e10	37	per_cpu(xen_resched_irq, cpu).irq = -1;
b85fffec KRW	38	kfree(per_cpu(xen_resched_irq, cpu).name);
b85fffec KRW	39	per_cpu(xen_resched_irq, cpu).name = NULL;
ee336e10 KRW	40	}
ee336e10 KRW	41	if (per_cpu(xen_callfunc_irq, cpu).irq >= 0) {
9547689f	42	unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu).irq, NULL);
ee336e10	43	per_cpu(xen_callfunc_irq, cpu).irq = -1;
b85fffec KRW	44	kfree(per_cpu(xen_callfunc_irq, cpu).name);
b85fffec KRW	45	per_cpu(xen_callfunc_irq, cpu).name = NULL;
ee336e10 KRW	46	}
ee336e10 KRW	47	if (per_cpu(xen_debug_irq, cpu).irq >= 0) {
9547689f	48	unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu).irq, NULL);
ee336e10	49	per_cpu(xen_debug_irq, cpu).irq = -1;
b85fffec KRW	50	kfree(per_cpu(xen_debug_irq, cpu).name);
b85fffec KRW	51	per_cpu(xen_debug_irq, cpu).name = NULL;
ee336e10 KRW	52	}
ee336e10 KRW	53	if (per_cpu(xen_callfuncsingle_irq, cpu).irq >= 0) {
9547689f	54	unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu).irq,
53b94fdc	55	NULL);
ee336e10	56	per_cpu(xen_callfuncsingle_irq, cpu).irq = -1;
b85fffec KRW	57	kfree(per_cpu(xen_callfuncsingle_irq, cpu).name);
b85fffec KRW	58	per_cpu(xen_callfuncsingle_irq, cpu).name = NULL;
ee336e10	59	}
04e95761	60	}
53b94fdc	61
5fc509bc	62	int xen_smp_intr_init(unsigned int cpu)
f87e4cac JF	63	{
f87e4cac JF	64	int rc;
04e95761	65	char resched_name, callfunc_name, *debug_name;
f87e4cac JF	66
	67	resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
	68	rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
	69	cpu,
	70	xen_reschedule_interrupt,
9d71cee6	71	IRQF_PERCPU\|IRQF_NOBALANCING,
f87e4cac JF	72	resched_name,
	73	NULL);
	74	if (rc < 0)
	75	goto fail;
9547689f	76	per_cpu(xen_resched_irq, cpu).irq = rc;
b85fffec	77	per_cpu(xen_resched_irq, cpu).name = resched_name;
f87e4cac JF	78
	79	callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
	80	rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
	81	cpu,
	82	xen_call_function_interrupt,
9d71cee6	83	IRQF_PERCPU\|IRQF_NOBALANCING,
f87e4cac JF	84	callfunc_name,
	85	NULL);
	86	if (rc < 0)
	87	goto fail;
9547689f	88	per_cpu(xen_callfunc_irq, cpu).irq = rc;
b85fffec	89	per_cpu(xen_callfunc_irq, cpu).name = callfunc_name;
f87e4cac	90
ee523ca1 JF	91	debug_name = kasprintf(GFP_KERNEL, "debug%d", cpu);
ee523ca1 JF	92	rc = bind_virq_to_irqhandler(VIRQ_DEBUG, cpu, xen_debug_interrupt,
9d71cee6	93	IRQF_PERCPU \| IRQF_NOBALANCING,
ee523ca1 JF	94	debug_name, NULL);
	95	if (rc < 0)
	96	goto fail;
9547689f	97	per_cpu(xen_debug_irq, cpu).irq = rc;
b85fffec	98	per_cpu(xen_debug_irq, cpu).name = debug_name;
ee523ca1	99
3b16cf87 JA	100	callfunc_name = kasprintf(GFP_KERNEL, "callfuncsingle%d", cpu);
	101	rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_SINGLE_VECTOR,
	102	cpu,
	103	xen_call_function_single_interrupt,
9d71cee6	104	IRQF_PERCPU\|IRQF_NOBALANCING,
3b16cf87 JA	105	callfunc_name,
	106	NULL);
	107	if (rc < 0)
	108	goto fail;
9547689f	109	per_cpu(xen_callfuncsingle_irq, cpu).irq = rc;
b85fffec	110	per_cpu(xen_callfuncsingle_irq, cpu).name = callfunc_name;
3b16cf87	111
04e95761 VK	112	return 0;
	113
	114	fail:
	115	xen_smp_intr_free(cpu);
	116	return rc;
	117	}
	118
ae039001 AA	119	void __init xen_smp_cpus_done(unsigned int max_cpus)
	120	{
	121	int cpu, rc, count = 0;
	122
	123	if (xen_hvm_domain())
	124	native_smp_cpus_done(max_cpus);
	125
	126	if (xen_have_vcpu_info_placement)
	127	return;
	128
	129	for_each_online_cpu(cpu) {
	130	if (xen_vcpu_nr(cpu) < MAX_VIRT_CPUS)
	131	continue;
	132
	133	rc = cpu_down(cpu);
	134
	135	if (rc == 0) {
	136	/*
	137	* Reset vcpu_info so this cpu cannot be onlined again.
	138	*/
	139	xen_vcpu_info_reset(cpu);
	140	count++;
	141	} else {
	142	pr_warn("%s: failed to bring CPU %d down, error %d\n",
	143	__func__, cpu, rc);
	144	}
	145	}
	146	WARN(count, "%s: brought %d CPUs offline\n", __func__, count);
	147	}
	148
a52482d9	149	void xen_smp_send_reschedule(int cpu)
f87e4cac JF	150	{
	151	xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
	152	}
	153
f447d56d BG	154	static void __xen_send_IPI_mask(const struct cpumask *mask,
f447d56d BG	155	int vector)
f87e4cac JF	156	{
	157	unsigned cpu;
	158
bcda016e	159	for_each_cpu_and(cpu, mask, cpu_online_mask)
f87e4cac JF	160	xen_send_IPI_one(cpu, vector);
	161	}
	162
a52482d9	163	void xen_smp_send_call_function_ipi(const struct cpumask *mask)
3b16cf87 JA	164	{
	165	int cpu;
	166
f447d56d	167	__xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
3b16cf87 JA	168
3b16cf87 JA	169	/* Make sure other vcpus get a chance to run if they need to. */
bcda016e	170	for_each_cpu(cpu, mask) {
3b16cf87	171	if (xen_vcpu_stolen(cpu)) {
1207cf8e	172	HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
3b16cf87 JA	173	break;
	174	}
	175	}
	176	}
	177
a52482d9	178	void xen_smp_send_call_function_single_ipi(int cpu)
3b16cf87	179	{
f447d56d	180	__xen_send_IPI_mask(cpumask_of(cpu),
e7986739	181	XEN_CALL_FUNCTION_SINGLE_VECTOR);
3b16cf87 JA	182	}
3b16cf87 JA	183
f447d56d BG	184	static inline int xen_map_vector(int vector)
	185	{
	186	int xen_vector;
	187
	188	switch (vector) {
	189	case RESCHEDULE_VECTOR:
	190	xen_vector = XEN_RESCHEDULE_VECTOR;
	191	break;
	192	case CALL_FUNCTION_VECTOR:
	193	xen_vector = XEN_CALL_FUNCTION_VECTOR;
	194	break;
	195	case CALL_FUNCTION_SINGLE_VECTOR:
	196	xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
	197	break;
1ff2b0c3 LM	198	case IRQ_WORK_VECTOR:
	199	xen_vector = XEN_IRQ_WORK_VECTOR;
	200	break;
6efa20e4 KRW	201	#ifdef CONFIG_X86_64
	202	case NMI_VECTOR:
	203	case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */
	204	xen_vector = XEN_NMI_VECTOR;
	205	break;
	206	#endif
f447d56d BG	207	default:
	208	xen_vector = -1;
	209	printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
	210	vector);
	211	}
	212
	213	return xen_vector;
	214	}
	215
	216	void xen_send_IPI_mask(const struct cpumask *mask,
	217	int vector)
	218	{
	219	int xen_vector = xen_map_vector(vector);
	220
	221	if (xen_vector >= 0)
	222	__xen_send_IPI_mask(mask, xen_vector);
	223	}
	224
	225	void xen_send_IPI_all(int vector)
	226	{
	227	int xen_vector = xen_map_vector(vector);
	228
	229	if (xen_vector >= 0)
	230	__xen_send_IPI_mask(cpu_online_mask, xen_vector);
	231	}
	232
	233	void xen_send_IPI_self(int vector)
	234	{
	235	int xen_vector = xen_map_vector(vector);
	236
	237	if (xen_vector >= 0)
	238	xen_send_IPI_one(smp_processor_id(), xen_vector);
	239	}
	240
	241	void xen_send_IPI_mask_allbutself(const struct cpumask *mask,
	242	int vector)
	243	{
	244	unsigned cpu;
	245	unsigned int this_cpu = smp_processor_id();
1db01b49	246	int xen_vector = xen_map_vector(vector);
f447d56d	247
1db01b49	248	if (!(num_online_cpus() > 1) \|\| (xen_vector < 0))
f447d56d BG	249	return;
	250
	251	for_each_cpu_and(cpu, mask, cpu_online_mask) {
	252	if (this_cpu == cpu)
	253	continue;
	254
1db01b49	255	xen_send_IPI_one(cpu, xen_vector);
f447d56d BG	256	}
	257	}
	258
	259	void xen_send_IPI_allbutself(int vector)
	260	{
1db01b49	261	xen_send_IPI_mask_allbutself(cpu_online_mask, vector);
f447d56d BG	262	}
f447d56d BG	263
f87e4cac JF	264	static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
f87e4cac JF	265	{
f87e4cac	266	irq_enter();
3b16cf87	267	generic_smp_call_function_interrupt();
1b437c8c	268	inc_irq_stat(irq_call_count);
f87e4cac JF	269	irq_exit();
f87e4cac JF	270
f87e4cac JF	271	return IRQ_HANDLED;
	272	}
	273
3b16cf87	274	static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
f87e4cac	275	{
3b16cf87 JA	276	irq_enter();
3b16cf87 JA	277	generic_smp_call_function_single_interrupt();
1b437c8c	278	inc_irq_stat(irq_call_count);
3b16cf87	279	irq_exit();
f87e4cac	280
3b16cf87	281	return IRQ_HANDLED;
f87e4cac	282	}