From: Juergen Gross jgross@suse.com
commit 7beb290caa2adb0a399e735a1e175db9aae0523a upstream.
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: Juergen Gross jgross@suse.com Reviewed-by: Jan Beulich jbeulich@suse.com Reviewed-by: Wei Liu wl@xen.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/xen/events/events_base.c | 25 +++++++++++++++++++++ drivers/xen/events/events_fifo.c | 40 ++++++++++++++++------------------- drivers/xen/events/events_internal.h | 3 ++ 3 files changed, 47 insertions(+), 21 deletions(-)
--- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -33,6 +33,7 @@ #include <linux/irqnr.h> #include <linux/pci.h> #include <linux/spinlock.h> +#include <linux/cpuhotplug.h>
#ifdef CONFIG_X86 #include <asm/desc.h> @@ -1833,6 +1834,26 @@ void xen_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; @@ -1843,6 +1864,10 @@ 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); --- a/drivers/xen/events/events_fifo.c +++ b/drivers/xen/events/events_fifo.c @@ -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_blo 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; } --- a/drivers/xen/events/events_internal.h +++ b/drivers/xen/events/events_internal.h @@ -71,6 +71,9 @@ 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;