Commit 7beb290c authored by Juergen Gross's avatar Juergen Gross
Browse files

xen/events: use a common cpu hotplug hook for event channels 



Today only fifo event channels have a cpu hotplug callback. In order
to prepare for more percpu (de)init work move that callback into
events_base.c and add percpu_init() and percpu_deinit() hooks to
struct evtchn_ops.

This is part of XSA-332.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
Reviewed-by: default avatarJan Beulich <jbeulich@suse.com>
Reviewed-by: default avatarWei Liu <wl@xen.org>
parent c44b849c

drivers/xen/events/events_base.c

+25 −0
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@ 
#include <linux/irqnr.h>

#include <linux/pci.h>

#include <linux/spinlock.h>

#include <linux/cpuhotplug.h>



#ifdef CONFIG_X86

#include <asm/desc.h>
@@ -1830,6 +1831,26 @@ static inline void xen_alloc_callback_vector(void) {} 
static bool fifo_events = true;

module_param(fifo_events, bool, 0);



static int xen_evtchn_cpu_prepare(unsigned int cpu)

{

	int ret = 0;



	if (evtchn_ops->percpu_init)

		ret = evtchn_ops->percpu_init(cpu);



	return ret;

}



static int xen_evtchn_cpu_dead(unsigned int cpu)

{

	int ret = 0;



	if (evtchn_ops->percpu_deinit)

		ret = evtchn_ops->percpu_deinit(cpu);



	return ret;

}



void __init xen_init_IRQ(void)

{

	int ret = -EINVAL;
@@ -1840,6 +1861,10 @@ void __init xen_init_IRQ(void) 
	if (ret < 0)

		xen_evtchn_2l_init();



	cpuhp_setup_state_nocalls(CPUHP_XEN_EVTCHN_PREPARE,

				  "xen/evtchn:prepare",

				  xen_evtchn_cpu_prepare, xen_evtchn_cpu_dead);



	evtchn_to_irq = kcalloc(EVTCHN_ROW(xen_evtchn_max_channels()),

				sizeof(*evtchn_to_irq), GFP_KERNEL);

	BUG_ON(!evtchn_to_irq);

drivers/xen/events/events_fifo.c

+19 −21
Original line number Diff line number Diff line
@@ -385,21 +385,6 @@ static void evtchn_fifo_resume(void) 
	event_array_pages = 0;

}



static const struct evtchn_ops evtchn_ops_fifo = {

	.max_channels      = evtchn_fifo_max_channels,

	.nr_channels       = evtchn_fifo_nr_channels,

	.setup             = evtchn_fifo_setup,

	.bind_to_cpu       = evtchn_fifo_bind_to_cpu,

	.clear_pending     = evtchn_fifo_clear_pending,

	.set_pending       = evtchn_fifo_set_pending,

	.is_pending        = evtchn_fifo_is_pending,

	.test_and_set_mask = evtchn_fifo_test_and_set_mask,

	.mask              = evtchn_fifo_mask,

	.unmask            = evtchn_fifo_unmask,

	.handle_events     = evtchn_fifo_handle_events,

	.resume            = evtchn_fifo_resume,

};



static int evtchn_fifo_alloc_control_block(unsigned cpu)

{

	void *control_block = NULL;
@@ -422,19 +407,36 @@ static int evtchn_fifo_alloc_control_block(unsigned cpu) 
	return ret;

}



static int xen_evtchn_cpu_prepare(unsigned int cpu)

static int evtchn_fifo_percpu_init(unsigned int cpu)

{

	if (!per_cpu(cpu_control_block, cpu))

		return evtchn_fifo_alloc_control_block(cpu);

	return 0;

}



static int xen_evtchn_cpu_dead(unsigned int cpu)

static int evtchn_fifo_percpu_deinit(unsigned int cpu)

{

	__evtchn_fifo_handle_events(cpu, true);

	return 0;

}



static const struct evtchn_ops evtchn_ops_fifo = {

	.max_channels      = evtchn_fifo_max_channels,

	.nr_channels       = evtchn_fifo_nr_channels,

	.setup             = evtchn_fifo_setup,

	.bind_to_cpu       = evtchn_fifo_bind_to_cpu,

	.clear_pending     = evtchn_fifo_clear_pending,

	.set_pending       = evtchn_fifo_set_pending,

	.is_pending        = evtchn_fifo_is_pending,

	.test_and_set_mask = evtchn_fifo_test_and_set_mask,

	.mask              = evtchn_fifo_mask,

	.unmask            = evtchn_fifo_unmask,

	.handle_events     = evtchn_fifo_handle_events,

	.resume            = evtchn_fifo_resume,

	.percpu_init       = evtchn_fifo_percpu_init,

	.percpu_deinit     = evtchn_fifo_percpu_deinit,

};



int __init xen_evtchn_fifo_init(void)

{

	int cpu = smp_processor_id();
@@ -448,9 +450,5 @@ int __init xen_evtchn_fifo_init(void) 


	evtchn_ops = &evtchn_ops_fifo;



	cpuhp_setup_state_nocalls(CPUHP_XEN_EVTCHN_PREPARE,

				  "xen/evtchn:prepare",

				  xen_evtchn_cpu_prepare, xen_evtchn_cpu_dead);



	return ret;

}

drivers/xen/events/events_internal.h

+3 −0
Original line number Diff line number Diff line
@@ -69,6 +69,9 @@ struct evtchn_ops { 


	void (*handle_events)(unsigned cpu);

	void (*resume)(void);



	int (*percpu_init)(unsigned int cpu);

	int (*percpu_deinit)(unsigned int cpu);

};



extern const struct evtchn_ops *evtchn_ops;

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