From fbbd5009e6ed1201731b1727762070c1a988e67d Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Mon, 14 Oct 2013 10:15:49 +0200 Subject: evtchn: refactor low-level event channel port ops Use functions for the low-level event channel port operations (set/clear pending, unmask, is_pending and is_masked). Group these functions into a struct evtchn_port_op so they can be replaced by alternate implementations (for different ABIs) on a per-domain basis. Signed-off-by: David Vrabel Reviewed-by: Jan Beulich Acked-by: Keir Fraser --- xen/arch/x86/irq.c | 11 +++--- xen/common/Makefile | 1 + xen/common/event_2l.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++ xen/common/event_channel.c | 87 ++++++++++++++++------------------------ xen/common/schedule.c | 3 +- xen/include/xen/event.h | 45 +++++++++++++++++++++ xen/include/xen/sched.h | 4 ++ 7 files changed, 189 insertions(+), 61 deletions(-) create mode 100644 xen/common/event_2l.c diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c index 7f547ff0b6..53fe9e32de 100644 --- a/xen/arch/x86/irq.c +++ b/xen/arch/x86/irq.c @@ -1474,7 +1474,7 @@ int pirq_guest_unmask(struct domain *d) { pirq = pirqs[i]->pirq; if ( pirqs[i]->masked && - !test_bit(pirqs[i]->evtchn, &shared_info(d, evtchn_mask)) ) + !evtchn_port_is_masked(d, evtchn_from_port(d, pirqs[i]->evtchn)) ) pirq_guest_eoi(pirqs[i]); } } while ( ++pirq < d->nr_pirqs && n == ARRAY_SIZE(pirqs) ); @@ -2222,6 +2222,7 @@ static void dump_irqs(unsigned char key) int i, irq, pirq; struct irq_desc *desc; irq_guest_action_t *action; + struct evtchn *evtchn; struct domain *d; const struct pirq *info; unsigned long flags; @@ -2262,13 +2263,11 @@ static void dump_irqs(unsigned char key) d = action->guest[i]; pirq = domain_irq_to_pirq(d, irq); info = pirq_info(d, pirq); + evtchn = evtchn_from_port(d, info->evtchn); printk("%u:%3d(%c%c%c)", d->domain_id, pirq, - (test_bit(info->evtchn, - &shared_info(d, evtchn_pending)) ? - 'P' : '-'), - (test_bit(info->evtchn, &shared_info(d, evtchn_mask)) ? - 'M' : '-'), + (evtchn_port_is_pending(d, evtchn) ? 'P' : '-'), + (evtchn_port_is_masked(d, evtchn) ? 'M' : '-'), (info->masked ? 'M' : '-')); if ( i != action->nr_guests ) printk(","); diff --git a/xen/common/Makefile b/xen/common/Makefile index fcb4a84e7c..f6c473a44a 100644 --- a/xen/common/Makefile +++ b/xen/common/Makefile @@ -5,6 +5,7 @@ obj-y += cpupool.o obj-$(HAS_DEVICE_TREE) += device_tree.o obj-y += domctl.o obj-y += domain.o +obj-y += event_2l.o obj-y += event_channel.o obj-y += grant_table.o obj-y += irq.o diff --git a/xen/common/event_2l.c b/xen/common/event_2l.c new file mode 100644 index 0000000000..7b28942933 --- /dev/null +++ b/xen/common/event_2l.c @@ -0,0 +1,99 @@ +/* + * Event channel port operations. + * + * Copyright (c) 2003-2006, K A Fraser. + * + * This source code is licensed under the GNU General Public License, + * Version 2 or later. See the file COPYING for more details. + */ + +#include +#include +#include +#include +#include +#include + +static void evtchn_2l_set_pending(struct vcpu *v, struct evtchn *evtchn) +{ + struct domain *d = v->domain; + unsigned int port = evtchn->port; + + /* + * The following bit operations must happen in strict order. + * NB. On x86, the atomic bit operations also act as memory barriers. + * There is therefore sufficiently strict ordering for this architecture -- + * others may require explicit memory barriers. + */ + + if ( test_and_set_bit(port, &shared_info(d, evtchn_pending)) ) + return; + + if ( !test_bit (port, &shared_info(d, evtchn_mask)) && + !test_and_set_bit(port / BITS_PER_EVTCHN_WORD(d), + &vcpu_info(v, evtchn_pending_sel)) ) + { + vcpu_mark_events_pending(v); + } + + evtchn_check_pollers(d, port); +} + +static void evtchn_2l_clear_pending(struct domain *d, struct evtchn *evtchn) +{ + clear_bit(evtchn->port, &shared_info(d, evtchn_pending)); +} + +static void evtchn_2l_unmask(struct domain *d, struct evtchn *evtchn) +{ + struct vcpu *v = d->vcpu[evtchn->notify_vcpu_id]; + unsigned int port = evtchn->port; + + /* + * These operations must happen in strict order. Based on + * evtchn_2l_set_pending() above. + */ + if ( test_and_clear_bit(port, &shared_info(d, evtchn_mask)) && + test_bit (port, &shared_info(d, evtchn_pending)) && + !test_and_set_bit (port / BITS_PER_EVTCHN_WORD(d), + &vcpu_info(v, evtchn_pending_sel)) ) + { + vcpu_mark_events_pending(v); + } +} + +static bool_t evtchn_2l_is_pending(struct domain *d, + const struct evtchn *evtchn) +{ + return test_bit(evtchn->port, &shared_info(d, evtchn_pending)); +} + +static bool_t evtchn_2l_is_masked(struct domain *d, + const struct evtchn *evtchn) +{ + return test_bit(evtchn->port, &shared_info(d, evtchn_mask)); +} + +static const struct evtchn_port_ops evtchn_port_ops_2l = +{ + .set_pending = evtchn_2l_set_pending, + .clear_pending = evtchn_2l_clear_pending, + .unmask = evtchn_2l_unmask, + .is_pending = evtchn_2l_is_pending, + .is_masked = evtchn_2l_is_masked, +}; + +void evtchn_2l_init(struct domain *d) +{ + d->evtchn_port_ops = &evtchn_port_ops_2l; +} + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * tab-width: 4 + * indent-tabs-mode: nil + * End: + */ diff --git a/xen/common/event_channel.c b/xen/common/event_channel.c index 64c976b20a..7290a21dc0 100644 --- a/xen/common/event_channel.c +++ b/xen/common/event_channel.c @@ -150,6 +150,7 @@ static int get_free_port(struct domain *d) xfree(chn); return -ENOMEM; } + chn[i].port = port + i; } bucket_from_port(d, port) = chn; @@ -530,7 +531,7 @@ static long __evtchn_close(struct domain *d1, int port1) } /* Clear pending event to avoid unexpected behavior on re-bind. */ - clear_bit(port1, &shared_info(d1, evtchn_pending)); + evtchn_port_clear_pending(d1, chn1); /* Reset binding to vcpu0 when the channel is freed. */ chn1->state = ECS_FREE; @@ -615,43 +616,7 @@ out: static void evtchn_set_pending(struct vcpu *v, int port) { - struct domain *d = v->domain; - int vcpuid; - - /* - * The following bit operations must happen in strict order. - * NB. On x86, the atomic bit operations also act as memory barriers. - * There is therefore sufficiently strict ordering for this architecture -- - * others may require explicit memory barriers. - */ - - if ( test_and_set_bit(port, &shared_info(d, evtchn_pending)) ) - return; - - if ( !test_bit (port, &shared_info(d, evtchn_mask)) && - !test_and_set_bit(port / BITS_PER_EVTCHN_WORD(d), - &vcpu_info(v, evtchn_pending_sel)) ) - { - vcpu_mark_events_pending(v); - } - - /* Check if some VCPU might be polling for this event. */ - if ( likely(bitmap_empty(d->poll_mask, d->max_vcpus)) ) - return; - - /* Wake any interested (or potentially interested) pollers. */ - for ( vcpuid = find_first_bit(d->poll_mask, d->max_vcpus); - vcpuid < d->max_vcpus; - vcpuid = find_next_bit(d->poll_mask, d->max_vcpus, vcpuid+1) ) - { - v = d->vcpu[vcpuid]; - if ( ((v->poll_evtchn <= 0) || (v->poll_evtchn == port)) && - test_and_clear_bit(vcpuid, d->poll_mask) ) - { - v->poll_evtchn = 0; - vcpu_unblock(v); - } - } + evtchn_port_set_pending(v, evtchn_from_port(v->domain, port)); } int guest_enabled_event(struct vcpu *v, uint32_t virq) @@ -920,26 +885,15 @@ long evtchn_bind_vcpu(unsigned int port, unsigned int vcpu_id) int evtchn_unmask(unsigned int port) { struct domain *d = current->domain; - struct vcpu *v; + struct evtchn *evtchn; ASSERT(spin_is_locked(&d->event_lock)); if ( unlikely(!port_is_valid(d, port)) ) return -EINVAL; - v = d->vcpu[evtchn_from_port(d, port)->notify_vcpu_id]; - - /* - * These operations must happen in strict order. Based on - * include/xen/event.h:evtchn_set_pending(). - */ - if ( test_and_clear_bit(port, &shared_info(d, evtchn_mask)) && - test_bit (port, &shared_info(d, evtchn_pending)) && - !test_and_set_bit (port / BITS_PER_EVTCHN_WORD(d), - &vcpu_info(v, evtchn_pending_sel)) ) - { - vcpu_mark_events_pending(v); - } + evtchn = evtchn_from_port(d, port); + evtchn_port_unmask(d, evtchn); return 0; } @@ -1170,9 +1124,34 @@ void notify_via_xen_event_channel(struct domain *ld, int lport) spin_unlock(&ld->event_lock); } +void evtchn_check_pollers(struct domain *d, unsigned int port) +{ + struct vcpu *v; + unsigned int vcpuid; + + /* Check if some VCPU might be polling for this event. */ + if ( likely(bitmap_empty(d->poll_mask, d->max_vcpus)) ) + return; + + /* Wake any interested (or potentially interested) pollers. */ + for ( vcpuid = find_first_bit(d->poll_mask, d->max_vcpus); + vcpuid < d->max_vcpus; + vcpuid = find_next_bit(d->poll_mask, d->max_vcpus, vcpuid+1) ) + { + v = d->vcpu[vcpuid]; + if ( ((v->poll_evtchn <= 0) || (v->poll_evtchn == port)) && + test_and_clear_bit(vcpuid, d->poll_mask) ) + { + v->poll_evtchn = 0; + vcpu_unblock(v); + } + } +} int evtchn_init(struct domain *d) { + evtchn_2l_init(d); + spin_lock_init(&d->event_lock); if ( get_free_port(d) != 0 ) return -EINVAL; @@ -1270,8 +1249,8 @@ static void domain_dump_evtchn_info(struct domain *d) printk(" %4u [%d/%d]: s=%d n=%d x=%d", port, - !!test_bit(port, &shared_info(d, evtchn_pending)), - !!test_bit(port, &shared_info(d, evtchn_mask)), + !!evtchn_port_is_pending(d, chn), + !!evtchn_port_is_masked(d, chn), chn->state, chn->notify_vcpu_id, chn->xen_consumer); switch ( chn->state ) diff --git a/xen/common/schedule.c b/xen/common/schedule.c index af3abc2f16..b8e4cb4417 100644 --- a/xen/common/schedule.c +++ b/xen/common/schedule.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include @@ -759,7 +760,7 @@ static long do_poll(struct sched_poll *sched_poll) goto out; rc = 0; - if ( test_bit(port, &shared_info(d, evtchn_pending)) ) + if ( evtchn_port_is_pending(d, evtchn_from_port(d, port)) ) goto out; } diff --git a/xen/include/xen/event.h b/xen/include/xen/event.h index 6f6016285d..30c59c9979 100644 --- a/xen/include/xen/event.h +++ b/xen/include/xen/event.h @@ -102,4 +102,49 @@ void notify_via_xen_event_channel(struct domain *ld, int lport); smp_mb(); /* set blocked status /then/ caller does his work */ \ } while ( 0 ) +void evtchn_check_pollers(struct domain *d, unsigned int port); + +void evtchn_2l_init(struct domain *d); + +/* + * Low-level event channel port ops. + */ +struct evtchn_port_ops { + void (*set_pending)(struct vcpu *v, struct evtchn *evtchn); + void (*clear_pending)(struct domain *d, struct evtchn *evtchn); + void (*unmask)(struct domain *d, struct evtchn *evtchn); + bool_t (*is_pending)(struct domain *d, const struct evtchn *evtchn); + bool_t (*is_masked)(struct domain *d, const struct evtchn *evtchn); +}; + +static inline void evtchn_port_set_pending(struct vcpu *v, + struct evtchn *evtchn) +{ + v->domain->evtchn_port_ops->set_pending(v, evtchn); +} + +static inline void evtchn_port_clear_pending(struct domain *d, + struct evtchn *evtchn) +{ + d->evtchn_port_ops->clear_pending(d, evtchn); +} + +static inline void evtchn_port_unmask(struct domain *d, + struct evtchn *evtchn) +{ + d->evtchn_port_ops->unmask(d, evtchn); +} + +static inline bool_t evtchn_port_is_pending(struct domain *d, + const struct evtchn *evtchn) +{ + return d->evtchn_port_ops->is_pending(d, evtchn); +} + +static inline bool_t evtchn_port_is_masked(struct domain *d, + const struct evtchn *evtchn) +{ + return d->evtchn_port_ops->is_masked(d, evtchn); +} + #endif /* __XEN_EVENT_H__ */ diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h index 2e83f08dd9..7c9eca38d2 100644 --- a/xen/include/xen/sched.h +++ b/xen/include/xen/sched.h @@ -66,6 +66,7 @@ struct evtchn u8 state; /* ECS_* */ u8 xen_consumer; /* Consumer in Xen, if any? (0 = send to guest) */ u16 notify_vcpu_id; /* VCPU for local delivery notification */ + u32 port; union { struct { domid_t remote_domid; @@ -238,6 +239,8 @@ struct mem_event_per_domain struct mem_event_domain access; }; +struct evtchn_port_ops; + struct domain { domid_t domain_id; @@ -271,6 +274,7 @@ struct domain /* Event channel information. */ struct evtchn *evtchn[NR_EVTCHN_BUCKETS]; spinlock_t event_lock; + const struct evtchn_port_ops *evtchn_port_ops; struct grant_table *grant_table; -- cgit v1.2.3