diff options
| -rw-r--r-- | drivers/xen/events/Makefile | 1 | ||||
| -rw-r--r-- | drivers/xen/events/events_2l.c | 348 | ||||
| -rw-r--r-- | drivers/xen/events/events_base.c | 379 | ||||
| -rw-r--r-- | drivers/xen/events/events_internal.h | 74 | ||||
| -rw-r--r-- | include/xen/events.h | 2 |
5 files changed, 442 insertions, 362 deletions
diff --git a/drivers/xen/events/Makefile b/drivers/xen/events/Makefile index f0bc6071fd84..08179fe04612 100644 --- a/drivers/xen/events/Makefile +++ b/drivers/xen/events/Makefile @@ -1,3 +1,4 @@ obj-y += events.o events-y += events_base.o +events-y += events_2l.o diff --git a/drivers/xen/events/events_2l.c b/drivers/xen/events/events_2l.c new file mode 100644 index 000000000000..a77e98d025fa --- /dev/null +++ b/drivers/xen/events/events_2l.c @@ -0,0 +1,348 @@ +/* + * Xen event channels (2-level ABI) + * + * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 + */ + +#define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt + +#include <linux/linkage.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/module.h> + +#include <asm/sync_bitops.h> +#include <asm/xen/hypercall.h> +#include <asm/xen/hypervisor.h> + +#include <xen/xen.h> +#include <xen/xen-ops.h> +#include <xen/events.h> +#include <xen/interface/xen.h> +#include <xen/interface/event_channel.h> + +#include "events_internal.h" + +/* + * Note sizeof(xen_ulong_t) can be more than sizeof(unsigned long). Be + * careful to only use bitops which allow for this (e.g + * test_bit/find_first_bit and friends but not __ffs) and to pass + * BITS_PER_EVTCHN_WORD as the bitmask length. + */ +#define BITS_PER_EVTCHN_WORD (sizeof(xen_ulong_t)*8) +/* + * Make a bitmask (i.e. unsigned long *) of a xen_ulong_t + * array. Primarily to avoid long lines (hence the terse name). + */ +#define BM(x) (unsigned long *)(x) +/* Find the first set bit in a evtchn mask */ +#define EVTCHN_FIRST_BIT(w) find_first_bit(BM(&(w)), BITS_PER_EVTCHN_WORD) + +static DEFINE_PER_CPU(xen_ulong_t [NR_EVENT_CHANNELS/BITS_PER_EVTCHN_WORD], + cpu_evtchn_mask); + +void xen_evtchn_port_bind_to_cpu(struct irq_info *info, int cpu) +{ + clear_bit(info->evtchn, BM(per_cpu(cpu_evtchn_mask, info->cpu))); + set_bit(info->evtchn, BM(per_cpu(cpu_evtchn_mask, cpu))); +} + +void clear_evtchn(int port) +{ + struct shared_info *s = HYPERVISOR_shared_info; + sync_clear_bit(port, BM(&s->evtchn_pending[0])); +} + +void set_evtchn(int port) +{ + struct shared_info *s = HYPERVISOR_shared_info; + sync_set_bit(port, BM(&s->evtchn_pending[0])); +} + +int test_evtchn(int port) +{ + struct shared_info *s = HYPERVISOR_shared_info; + return sync_test_bit(port, BM(&s->evtchn_pending[0])); +} + +int test_and_set_mask(int port) +{ + struct shared_info *s = HYPERVISOR_shared_info; + return sync_test_and_set_bit(port, BM(&s->evtchn_mask[0])); +} + +void mask_evtchn(int port) +{ + struct shared_info *s = HYPERVISOR_shared_info; + sync_set_bit(port, BM(&s->evtchn_mask[0])); +} + +void unmask_evtchn(int port) +{ + struct shared_info *s = HYPERVISOR_shared_info; + unsigned int cpu = get_cpu(); + int do_hypercall = 0, evtchn_pending = 0; + + BUG_ON(!irqs_disabled()); + + if (unlikely((cpu != cpu_from_evtchn(port)))) + do_hypercall = 1; + else { + /* + * Need to clear the mask before checking pending to + * avoid a race with an event becoming pending. + * + * EVTCHNOP_unmask will only trigger an upcall if the + * mask bit was set, so if a hypercall is needed + * remask the event. + */ + sync_clear_bit(port, BM(&s->evtchn_mask[0])); + evtchn_pending = sync_test_bit(port, BM(&s->evtchn_pending[0])); + + if (unlikely(evtchn_pending && xen_hvm_domain())) { + sync_set_bit(port, BM(&s->evtchn_mask[0])); + do_hypercall = 1; + } + } + + /* Slow path (hypercall) if this is a non-local port or if this is + * an hvm domain and an event is pending (hvm domains don't have + * their own implementation of irq_enable). */ + if (do_hypercall) { + struct evtchn_unmask unmask = { .port = port }; + (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask); + } else { + struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu); + + /* + * The following is basically the equivalent of + * 'hw_resend_irq'. Just like a real IO-APIC we 'lose + * the interrupt edge' if the channel is masked. + */ + if (evtchn_pending && + !sync_test_and_set_bit(port / BITS_PER_EVTCHN_WORD, + BM(&vcpu_info->evtchn_pending_sel))) + vcpu_info->evtchn_upcall_pending = 1; + } + + put_cpu(); +} + +static DEFINE_PER_CPU(unsigned int, current_word_idx); +static DEFINE_PER_CPU(unsigned int, current_bit_idx); + +/* + * Mask out the i least significant bits of w + */ +#define MASK_LSBS(w, i) (w & ((~((xen_ulong_t)0UL)) << i)) + +static inline xen_ulong_t active_evtchns(unsigned int cpu, + struct shared_info *sh, + unsigned int idx) +{ + return sh->evtchn_pending[idx] & + per_cpu(cpu_evtchn_mask, cpu)[idx] & + ~sh->evtchn_mask[idx]; +} + +/* + * Search the CPU's pending events bitmasks. For each one found, map + * the event number to an irq, and feed it into do_IRQ() for handling. + * + * Xen uses a two-level bitmap to speed searching. The first level is + * a bitset of words which contain pending event bits. The second + * level is a bitset of pending events themselves. + */ +void xen_evtchn_handle_events(int cpu) +{ + int irq; + xen_ulong_t pending_words; + xen_ulong_t pending_bits; + int start_word_idx, start_bit_idx; + int word_idx, bit_idx; + int i; + struct irq_desc *desc; + struct shared_info *s = HYPERVISOR_shared_info; + struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu); + + /* Timer interrupt has highest priority. */ + irq = irq_from_virq(cpu, VIRQ_TIMER); + if (irq != -1) { + unsigned int evtchn = evtchn_from_irq(irq); + word_idx = evtchn / BITS_PER_LONG; + bit_idx = evtchn % BITS_PER_LONG; + if (active_evtchns(cpu, s, word_idx) & (1ULL << bit_idx)) { + desc = irq_to_desc(irq); + if (desc) + generic_handle_irq_desc(irq, desc); + } + } + + /* + * Master flag must be cleared /before/ clearing + * selector flag. xchg_xen_ulong must contain an + * appropriate barrier. + */ + pending_words = xchg_xen_ulong(&vcpu_info->evtchn_pending_sel, 0); + + start_word_idx = __this_cpu_read(current_word_idx); + start_bit_idx = __this_cpu_read(current_bit_idx); + + word_idx = start_word_idx; + + for (i = 0; pending_words != 0; i++) { + xen_ulong_t words; + + words = MASK_LSBS(pending_words, word_idx); + + /* + * If we masked out all events, wrap to beginning. + */ + if (words == 0) { + word_idx = 0; + bit_idx = 0; + continue; + } + word_idx = EVTCHN_FIRST_BIT(words); + + pending_bits = active_evtchns(cpu, s, word_idx); + bit_idx = 0; /* usually scan entire word from start */ + /* + * We scan the starting word in two parts. + * + * 1st time: start in the middle, scanning the + * upper bits. + * + * 2nd time: scan the whole word (not just the + * parts skipped in the first pass) -- if an + * event in the previously scanned bits is + * pending again it would just be scanned on + * the next loop anyway. + */ + if (word_idx == start_word_idx) { + if (i == 0) + bit_idx = start_bit_idx; + } + + do { + xen_ulong_t bits; + int port; + + bits = MASK_LSBS(pending_bits, bit_idx); + + /* If we masked out all events, move on. */ + if (bits == 0) + break; + + bit_idx = EVTCHN_FIRST_BIT(bits); + + /* Process port. */ + port = (word_idx * BITS_PER_EVTCHN_WORD) + bit_idx; + irq = evtchn_to_irq[port]; + + if (irq != -1) { + desc = irq_to_desc(irq); + if (desc) + generic_handle_irq_desc(irq, desc); + } + + bit_idx = (bit_idx + 1) % BITS_PER_EVTCHN_WORD; + + /* Next caller starts at last processed + 1 */ + __this_cpu_write(current_word_idx, + bit_idx ? word_idx : + (word_idx+1) % BITS_PER_EVTCHN_WORD); + __this_cpu_write(current_bit_idx, bit_idx); + } while (bit_idx != 0); + + /* Scan start_l1i twice; all others once. */ + if ((word_idx != start_word_idx) || (i != 0)) + pending_words &= ~(1UL << word_idx); + + word_idx = (word_idx + 1) % BITS_PER_EVTCHN_WORD; + } +} + +irqreturn_t xen_debug_interrupt(int irq, void *dev_id) +{ + struct shared_info *sh = HYPERVISOR_shared_info; + int cpu = smp_processor_id(); + xen_ulong_t *cpu_evtchn = per_cpu(cpu_evtchn_mask, cpu); + int i; + unsigned long flags; + static DEFINE_SPINLOCK(debug_lock); + struct vcpu_info *v; + + spin_lock_irqsave(&debug_lock, flags); + + printk("\nvcpu %d\n ", cpu); + + for_each_online_cpu(i) { + int pending; + v = per_cpu(xen_vcpu, i); + pending = (get_irq_regs() && i == cpu) + ? xen_irqs_disabled(get_irq_regs()) + : v->evtchn_upcall_mask; + printk("%d: masked=%d pending=%d event_sel %0*"PRI_xen_ulong"\n ", i, + pending, v->evtchn_upcall_pending, + (int)(sizeof(v->evtchn_pending_sel)*2), + v->evtchn_pending_sel); + } + v = per_cpu(xen_vcpu, cpu); + + printk("\npending:\n "); + for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--) + printk("%0*"PRI_xen_ulong"%s", + (int)sizeof(sh->evtchn_pending[0])*2, + sh->evtchn_pending[i], + i % 8 == 0 ? "\n " : " "); + printk("\nglobal mask:\n "); + for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) + printk("%0*"PRI_xen_ulong"%s", + (int)(sizeof(sh->evtchn_mask[0])*2), + sh->evtchn_mask[i], + i % 8 == 0 ? "\n " : " "); + + printk("\nglobally unmasked:\n "); + for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) + printk("%0*"PRI_xen_ulong"%s", + (int)(sizeof(sh->evtchn_mask[0])*2), + sh->evtchn_pending[i] & ~sh->evtchn_mask[i], + i % 8 == 0 ? "\n " : " "); + + printk("\nlocal cpu%d mask:\n ", cpu); + for (i = (NR_EVENT_CHANNELS/BITS_PER_EVTCHN_WORD)-1; i >= 0; i--) + printk("%0*"PRI_xen_ulong"%s", (int)(sizeof(cpu_evtchn[0])*2), + cpu_evtchn[i], + i % 8 == 0 ? "\n " : " "); + + printk("\nlocally unmasked:\n "); + for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) { + xen_ulong_t pending = sh->evtchn_pending[i] + & ~sh->evtchn_mask[i] + & cpu_evtchn[i]; + printk("%0*"PRI_xen_ulong"%s", + (int)(sizeof(sh->evtchn_mask[0])*2), + pending, i % 8 == 0 ? "\n " : " "); + } + + printk("\npending list:\n"); + for (i = 0; i < NR_EVENT_CHANNELS; i++) { + if (sync_test_bit(i, BM(sh->evtchn_pending))) { + int word_idx = i / BITS_PER_EVTCHN_WORD; + printk(" %d: event %d -> irq %d%s%s%s\n", + cpu_from_evtchn(i), i, + evtchn_to_irq[i], + sync_test_bit(word_idx, BM(&v->evtchn_pending_sel)) + ? "" : " l2-clear", + !sync_test_bit(i, BM(sh->evtchn_mask)) + ? "" : " globally-masked", + sync_test_bit(i, BM(cpu_evtchn)) + ? "" : " locally-masked"); + } + } + + spin_unlock_irqrestore(&debug_lock, flags); + + return IRQ_HANDLED; +} diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index fec5da4ff3a0..8771b740e30f 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -59,6 +59,8 @@ #include <xen/interface/vcpu.h> #include <asm/hw_irq.h> +#include "events_internal.h" + /* * This lock protects updates to the following mapping and reference-count * arrays. The lock does not need to be acquired to read the mapping tables. @@ -73,72 +75,12 @@ static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1}; /* IRQ <-> IPI mapping */ static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1}; -/* Interrupt types. */ -enum xen_irq_type { - IRQT_UNBOUND = 0, - IRQT_PIRQ, - IRQT_VIRQ, - IRQT_IPI, - IRQT_EVTCHN -}; - -/* - * Packed IRQ information: - * type - enum xen_irq_type - * event channel - irq->event channel mapping - * cpu - cpu this event channel is bound to - * index - type-specific information: - * PIRQ - physical IRQ, GSI, flags, and owner domain - * VIRQ - virq number - * IPI - IPI vector - * EVTCHN - - */ -struct irq_info { - struct list_head list; - int refcnt; - enum xen_irq_type type; /* type */ - unsigned irq; - unsigned short evtchn; /* event channel */ - unsigned short cpu; /* cpu bound */ - - union { - unsigned short virq; - enum ipi_vector ipi; - struct { - unsigned short pirq; - unsigned short gsi; - unsigned char flags; - uint16_t domid; - } pirq; - } u; -}; -#define PIRQ_NEEDS_EOI (1 << 0) -#define PIRQ_SHAREABLE (1 << 1) - -static int *evtchn_to_irq; +int *evtchn_to_irq; #ifdef CONFIG_X86 static unsigned long *pirq_eoi_map; #endif static bool (*pirq_needs_eoi)(unsigned irq); -/* - * Note sizeof(xen_ulong_t) can be more than sizeof(unsigned long). Be - * careful to only use bitops which allow for this (e.g - * test_bit/find_first_bit and friends but not __ffs) and to pass - * BITS_PER_EVTCHN_WORD as the bitmask length. - */ -#define BITS_PER_EVTCHN_WORD (sizeof(xen_ulong_t)*8) -/* - * Make a bitmask (i.e. unsigned long *) of a xen_ulong_t - * array. Primarily to avoid long lines (hence the terse name). - */ -#define BM(x) (unsigned long *)(x) -/* Find the first set bit in a evtchn mask */ -#define EVTCHN_FIRST_BIT(w) find_first_bit(BM(&(w)), BITS_PER_EVTCHN_WORD) - -static DEFINE_PER_CPU(xen_ulong_t [NR_EVENT_CHANNELS/BITS_PER_EVTCHN_WORD], - cpu_evtchn_mask); - /* Xen will never allocate port zero for any purpose. */ #define VALID_EVTCHN(chn) ((chn) != 0) @@ -149,7 +91,7 @@ static void enable_dynirq(struct irq_data *data); static void disable_dynirq(struct irq_data *data); /* Get info for IRQ */ -static struct irq_info *info_for_irq(unsigned irq) +struct irq_info *info_for_irq(unsigned irq) { return irq_get_handler_data(irq); } @@ -230,7 +172,7 @@ static void xen_irq_info_pirq_init(unsigned irq, /* * Accessors for packed IRQ information. */ -static unsigned int evtchn_from_irq(unsigned irq) +unsigned int evtchn_from_irq(unsigned irq) { if (unlikely(WARN(irq < 0 || irq >= nr_irqs, "Invalid irq %d!\n", irq))) return 0; @@ -244,6 +186,11 @@ unsigned irq_from_evtchn(unsigned int evtchn) } EXPORT_SYMBOL_GPL(irq_from_evtchn); +int irq_from_virq(unsigned int cpu, unsigned int virq) +{ + return per_cpu(virq_to_irq, cpu)[virq]; +} + static enum ipi_vector ipi_from_irq(unsigned irq) { struct irq_info *info = info_for_irq(irq); @@ -279,12 +226,12 @@ static enum xen_irq_type type_from_irq(unsigned irq) return info_for_irq(irq)->type; } -static unsigned cpu_from_irq(unsigned irq) +unsigned cpu_from_irq(unsigned irq) { return info_for_irq(irq)->cpu; } -static unsigned int cpu_from_evtchn(unsigned int evtchn) +unsigned int cpu_from_evtchn(unsigned int evtchn) { int irq = evtchn_to_irq[evtchn]; unsigned ret = 0; @@ -310,55 +257,21 @@ static bool pirq_needs_eoi_flag(unsigned irq) return info->u.pirq.flags & PIRQ_NEEDS_EOI; } -static inline xen_ulong_t active_evtchns(unsigned int cpu, - struct shared_info *sh, - unsigned int idx) -{ - return sh->evtchn_pending[idx] & - per_cpu(cpu_evtchn_mask, cpu)[idx] & - ~sh->evtchn_mask[idx]; -} - static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu) { int irq = evtchn_to_irq[chn]; + struct irq_info *info = info_for_irq(irq); BUG_ON(irq == -1); #ifdef CONFIG_SMP cpumask_copy(irq_to_desc(irq)->irq_data.affinity, cpumask_of(cpu)); #endif - clear_bit(chn, BM(per_cpu(cpu_evtchn_mask, cpu_from_irq(irq)))); - set_bit(chn, BM(per_cpu(cpu_evtchn_mask, cpu))); + xen_evtchn_port_bind_to_cpu(info, cpu); - info_for_irq(irq)->cpu = cpu; -} - -static inline void clear_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - sync_clear_bit(port, BM(&s->evtchn_pending[0])); -} - -static inline void set_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - sync_set_bit(port, BM(&s->evtchn_pending[0])); -} - -static inline int test_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - return sync_test_bit(port, BM(&s->evtchn_pending[0])); -} - -static inline int test_and_set_mask(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - return sync_test_and_set_bit(port, BM(&s->evtchn_mask[0])); + info->cpu = cpu; } - /** * notify_remote_via_irq - send event to remote end of event channel via irq * @irq: irq of event channel to send event to @@ -376,63 +289,6 @@ void notify_remote_via_irq(int irq) } EXPORT_SYMBOL_GPL(notify_remote_via_irq); -static void mask_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - sync_set_bit(port, BM(&s->evtchn_mask[0])); -} - -static void unmask_evtchn(int port) -{ - struct shared_info *s = HYPERVISOR_shared_info; - unsigned int cpu = get_cpu(); - int do_hypercall = 0, evtchn_pending = 0; - - BUG_ON(!irqs_disabled()); - - if (unlikely((cpu != cpu_from_evtchn(port)))) - do_hypercall = 1; - else { - /* - * Need to clear the mask before checking pending to - * avoid a race with an event becoming pending. - * - * EVTCHNOP_unmask will only trigger an upcall if the - * mask bit was set, so if a hypercall is needed - * remask the event. - */ - sync_clear_bit(port, BM(&s->evtchn_mask[0])); - evtchn_pending = sync_test_bit(port, BM(&s->evtchn_pending[0])); - - if (unlikely(evtchn_pending && xen_hvm_domain())) { - sync_set_bit(port, BM(&s->evtchn_mask[0])); - do_hypercall = 1; - } - } - - /* Slow path (hypercall) if this is a non-local port or if this is - * an hvm domain and an event is pending (hvm domains don't have - * their own implementation of irq_enable). */ - if (do_hypercall) { - struct evtchn_unmask unmask = { .port = port }; - (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask); - } else { - struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu); - - /* - * The following is basically the equivalent of - * 'hw_resend_irq'. Just like a real IO-APIC we 'lose - * the interrupt edge' if the channel is masked. - */ - if (evtchn_pending && - !sync_test_and_set_bit(port / BITS_PER_EVTCHN_WORD, - BM(&vcpu_info->evtchn_pending_sel))) - vcpu_info->evtchn_upcall_pending = 1; - } - - put_cpu(); -} - static void xen_irq_init(unsigned irq) { struct irq_info *info; @@ -1216,222 +1072,21 @@ void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector) notify_remote_via_irq(irq); } -irqreturn_t xen_debug_interrupt(int irq, void *dev_id) -{ - struct shared_info *sh = HYPERVISOR_shared_info; - int cpu = smp_processor_id(); - xen_ulong_t *cpu_evtchn = per_cpu(cpu_evtchn_mask, cpu); - int i; - unsigned long flags; - static DEFINE_SPINLOCK(debug_lock); - struct vcpu_info *v; - - spin_lock_irqsave(&debug_lock, flags); - - printk("\nvcpu %d\n ", cpu); - - for_each_online_cpu(i) { - int pending; - v = per_cpu(xen_vcpu, i); - pending = (get_irq_regs() && i == cpu) - ? xen_irqs_disabled(get_irq_regs()) - : v->evtchn_upcall_mask; - printk("%d: masked=%d pending=%d event_sel %0*"PRI_xen_ulong"\n ", i, - pending, v->evtchn_upcall_pending, - (int)(sizeof(v->evtchn_pending_sel)*2), - v->evtchn_pending_sel); - } - v = per_cpu(xen_vcpu, cpu); - - printk("\npending:\n "); - for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--) - printk("%0*"PRI_xen_ulong"%s", - (int)sizeof(sh->evtchn_pending[0])*2, - sh->evtchn_pending[i], - i % 8 == 0 ? "\n " : " "); - printk("\nglobal mask:\n "); - for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) - printk("%0*"PRI_xen_ulong"%s", - (int)(sizeof(sh->evtchn_mask[0])*2), - sh->evtchn_mask[i], - i % 8 == 0 ? "\n " : " "); - - printk("\nglobally unmasked:\n "); - for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) - printk("%0*"PRI_xen_ulong"%s", - (int)(sizeof(sh->evtchn_mask[0])*2), - sh->evtchn_pending[i] & ~sh->evtchn_mask[i], - i % 8 == 0 ? "\n " : " "); - - printk("\nlocal cpu%d mask:\n ", cpu); - for (i = (NR_EVENT_CHANNELS/BITS_PER_EVTCHN_WORD)-1; i >= 0; i--) - printk("%0*"PRI_xen_ulong"%s", (int)(sizeof(cpu_evtchn[0])*2), - cpu_evtchn[i], - i % 8 == 0 ? "\n " : " "); - - printk("\nlocally unmasked:\n "); - for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) { - xen_ulong_t pending = sh->evtchn_pending[i] - & ~sh->evtchn_mask[i] - & cpu_evtchn[i]; - printk("%0*"PRI_xen_ulong"%s", - (int)(sizeof(sh->evtchn_mask[0])*2), - pending, i % 8 == 0 ? "\n " : " "); - } - - printk("\npending list:\n"); - for (i = 0; i < NR_EVENT_CHANNELS; i++) { - if (sync_test_bit(i, BM(sh->evtchn_pending))) { - int word_idx = i / BITS_PER_EVTCHN_WORD; - printk(" %d: event %d -> irq %d%s%s%s\n", - cpu_from_evtchn(i), i, - evtchn_to_irq[i], - sync_test_bit(word_idx, BM(&v->evtchn_pending_sel)) - ? "" : " l2-clear", - !sync_test_bit(i, BM(sh->evtchn_mask)) - ? "" : " globally-masked", - sync_test_bit(i, BM(cpu_evtchn)) - ? "" : " locally-masked"); - } - } - - spin_unlock_irqrestore(&debug_lock, flags); - - return IRQ_HANDLED; -} - static DEFINE_PER_CPU(unsigned, xed_nesting_count); -static DEFINE_PER_CPU(unsigned int, current_word_idx); -static DEFINE_PER_CPU(unsigned int, current_bit_idx); -/* - * Mask out the i least significant bits of w - */ -#define MASK_LSBS(w, i) (w & ((~((xen_ulong_t)0UL)) << i)) - -/* - * Search the CPUs pending events bitmasks. For each one found, map - * the event number to an irq, and feed it into do_IRQ() for - * handling. - * - * Xen uses a two-level bitmap to speed searching. The first level is - * a bitset of words which contain pending event bits. The second - * level is a bitset of pending events themselves. - */ static void __xen_evtchn_do_upcall(void) { - int start_word_idx, start_bit_idx; - int word_idx, bit_idx; - int i, irq; - int cpu = get_cpu(); - struct shared_info *s = HYPERVISOR_shared_info; struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu); + int cpu = get_cpu(); unsigned count; do { - xen_ulong_t pending_words; - xen_ulong_t pending_bits; - struct irq_desc *desc; - vcpu_info->evtchn_upcall_pending = 0; if (__this_cpu_inc_return(xed_nesting_count) - 1) goto out; - /* - * Master flag must be cleared /before/ clearing - * selector flag. xchg_xen_ulong must contain an - * appropriate barrier. - */ - if ((irq = per_cpu(virq_to_irq, cpu)[VIRQ_TIMER]) != -1) { - int evtchn = evtchn_from_irq(irq); - word_idx = evtchn / BITS_PER_LONG; - pending_bits = evtchn % BITS_PER_LONG; - if (active_evtchns(cpu, s, word_idx) & (1ULL << pending_bits)) { - desc = irq_to_desc(irq); - if (desc) - generic_handle_irq_desc(irq, desc); - } - } - - pending_words = xchg_xen_ulong(&vcpu_info->evtchn_pending_sel, 0); - - start_word_idx = __this_cpu_read(current_word_idx); - start_bit_idx = __this_cpu_read(current_bit_idx); - - word_idx = start_word_idx; - - for (i = 0; pending_words != 0; i++) { - xen_ulong_t words; - - words = MASK_LSBS(pending_words, word_idx); - - /* - * If we masked out all events, wrap to beginning. - */ - if (words == 0) { - word_idx = 0; - bit_idx = 0; - continue; - } - word_idx = EVTCHN_FIRST_BIT(words); - - pending_bits = active_evtchns(cpu, s, word_idx); - bit_idx = 0; /* usually scan entire word from start */ - /* - * We scan the starting word in two parts. - * - * 1st time: start in the middle, scanning the - * upper bits. - * - * 2nd time: scan the whole word (not just the - * parts skipped in the first pass) -- if an - * event in the previously scanned bits is - * pending again it would just be scanned on - * the next loop anyway. - */ - if (word_idx == start_word_idx) { - if (i == 0) - bit_idx = start_bit_idx; - } - - do { - xen_ulong_t bits; - int port; - - bits = MASK_LSBS(pending_bits, bit_idx); - - /* If we masked out all events, move on. */ - if (bits == 0) - break; - - bit_idx = EVTCHN_FIRST_BIT(bits); - - /* Process port. */ - port = (word_idx * BITS_PER_EVTCHN_WORD) + bit_idx; - irq = evtchn_to_irq[port]; - - if (irq != -1) { - desc = irq_to_desc(irq); - if (desc) - generic_handle_irq_desc(irq, desc); - } - - bit_idx = (bit_idx + 1) % BITS_PER_EVTCHN_WORD; - - /* Next caller starts at last processed + 1 */ - __this_cpu_write(current_word_idx, - bit_idx ? word_idx : - (word_idx+1) % BITS_PER_EVTCHN_WORD); - __this_cpu_write(current_bit_idx, bit_idx); - } while (bit_idx != 0); - - /* Scan start_l1i twice; all others once. */ - if ((word_idx != start_word_idx) || (i != 0)) - pending_words &= ~(1UL << word_idx); - - word_idx = (word_idx + 1) % BITS_PER_EVTCHN_WORD; - } + xen_evtchn_handle_events(cpu); BUG_ON(!irqs_disabled()); diff --git a/drivers/xen/events/events_internal.h b/drivers/xen/events/events_internal.h new file mode 100644 index 000000000000..79ac70bbbd26 --- /dev/null +++ b/drivers/xen/events/events_internal.h @@ -0,0 +1,74 @@ +/* + * Xen Event Channels (internal header) + * + * Copyright (C) 2013 Citrix Systems R&D Ltd. + * + * This source code is licensed under the GNU General Public License, + * Version 2 or later. See the file COPYING for more details. + */ +#ifndef __EVENTS_INTERNAL_H__ +#define __EVENTS_INTERNAL_H__ + +/* Interrupt types. */ +enum xen_irq_type { + IRQT_UNBOUND = 0, + IRQT_PIRQ, + IRQT_VIRQ, + IRQT_IPI, + IRQT_EVTCHN +}; + +/* + * Packed IRQ information: + * type - enum xen_irq_type + * event channel - irq->event channel mapping + * cpu - cpu this event channel is bound to + * index - type-specific information: + * PIRQ - vector, with MSB being "needs EIO", or physical IRQ of the HVM + * guest, or GSI (real passthrough IRQ) of the device. + * VIRQ - virq number + * IPI - IPI vector + * EVTCHN - + */ +struct irq_info { + struct list_head list; + int refcnt; + enum xen_irq_type type; /* type */ + unsigned irq; + unsigned short evtchn; /* event channel */ + unsigned short cpu; /* cpu bound */ + + union { + unsigned short virq; + enum ipi_vector ipi; + struct { + unsigned short pirq; + unsigned short gsi; + unsigned char vector; + unsigned char flags; + uint16_t domid; + } pirq; + } u; +}; + +#define PIRQ_NEEDS_EOI (1 << 0) +#define PIRQ_SHAREABLE (1 << 1) + +extern int *evtchn_to_irq; + +struct irq_info *info_for_irq(unsigned irq); +unsigned cpu_from_irq(unsigned irq); +unsigned cpu_from_evtchn(unsigned int evtchn); + +void xen_evtchn_port_bind_to_cpu(struct irq_info *info, int cpu); + +void clear_evtchn(int port); +void set_evtchn(int port); +int test_evtchn(int port); +int test_and_set_mask(int port); +void mask_evtchn(int port); +void unmask_evtchn(int port); + +void xen_evtchn_handle_events(int cpu); + +#endif /* #ifndef __EVENTS_INTERNAL_H__ */ diff --git a/include/xen/events.h b/include/xen/events.h index c9ea10ee2273..32ae0f263749 100644 --- a/include/xen/events.h +++ b/include/xen/events.h @@ -73,6 +73,8 @@ void xen_poll_irq_timeout(int irq, u64 timeout); /* Determine the IRQ which is bound to an event channel */ unsigned irq_from_evtchn(unsigned int evtchn); +int irq_from_virq(unsigned int cpu, unsigned int virq); +unsigned int evtchn_from_irq(unsigned irq); /* Xen HVM evtchn vector callback */ void xen_hvm_callback_vector(void); |
