diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/irq/affinity.c | 121 | ||||
| -rw-r--r-- | kernel/irq/chip.c | 66 | ||||
| -rw-r--r-- | kernel/irq/debugfs.c | 8 | ||||
| -rw-r--r-- | kernel/irq/handle.c | 2 | ||||
| -rw-r--r-- | kernel/irq/internals.h | 10 | ||||
| -rw-r--r-- | kernel/irq/irqdesc.c | 42 | ||||
| -rw-r--r-- | kernel/irq/irqdomain.c | 16 | ||||
| -rw-r--r-- | kernel/irq/manage.c | 406 | ||||
| -rw-r--r-- | kernel/kthread.c | 8 | ||||
| -rw-r--r-- | kernel/softirq.c | 3 |
10 files changed, 617 insertions, 65 deletions
diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c index 45b68b4ea48b..f18cd5aa33e8 100644 --- a/kernel/irq/affinity.c +++ b/kernel/irq/affinity.c @@ -9,7 +9,7 @@ #include <linux/cpu.h> static void irq_spread_init_one(struct cpumask *irqmsk, struct cpumask *nmsk, - int cpus_per_vec) + unsigned int cpus_per_vec) { const struct cpumask *siblmsk; int cpu, sibl; @@ -95,15 +95,17 @@ static int get_nodes_in_cpumask(cpumask_var_t *node_to_cpumask, } static int __irq_build_affinity_masks(const struct irq_affinity *affd, - int startvec, int numvecs, int firstvec, + unsigned int startvec, + unsigned int numvecs, + unsigned int firstvec, cpumask_var_t *node_to_cpumask, const struct cpumask *cpu_mask, struct cpumask *nmsk, struct irq_affinity_desc *masks) { - int n, nodes, cpus_per_vec, extra_vecs, done = 0; - int last_affv = firstvec + numvecs; - int curvec = startvec; + unsigned int n, nodes, cpus_per_vec, extra_vecs, done = 0; + unsigned int last_affv = firstvec + numvecs; + unsigned int curvec = startvec; nodemask_t nodemsk = NODE_MASK_NONE; if (!cpumask_weight(cpu_mask)) @@ -117,18 +119,16 @@ static int __irq_build_affinity_masks(const struct irq_affinity *affd, */ if (numvecs <= nodes) { for_each_node_mask(n, nodemsk) { - cpumask_or(&masks[curvec].mask, - &masks[curvec].mask, - node_to_cpumask[n]); + cpumask_or(&masks[curvec].mask, &masks[curvec].mask, + node_to_cpumask[n]); if (++curvec == last_affv) curvec = firstvec; } - done = numvecs; - goto out; + return numvecs; } for_each_node_mask(n, nodemsk) { - int ncpus, v, vecs_to_assign, vecs_per_node; + unsigned int ncpus, v, vecs_to_assign, vecs_per_node; /* Spread the vectors per node */ vecs_per_node = (numvecs - (curvec - firstvec)) / nodes; @@ -163,8 +163,6 @@ static int __irq_build_affinity_masks(const struct irq_affinity *affd, curvec = firstvec; --nodes; } - -out: return done; } @@ -174,19 +172,24 @@ out: * 2) spread other possible CPUs on these vectors */ static int irq_build_affinity_masks(const struct irq_affinity *affd, - int startvec, int numvecs, int firstvec, - cpumask_var_t *node_to_cpumask, + unsigned int startvec, unsigned int numvecs, + unsigned int firstvec, struct irq_affinity_desc *masks) { - int curvec = startvec, nr_present, nr_others; - int ret = -ENOMEM; + unsigned int curvec = startvec, nr_present, nr_others; + cpumask_var_t *node_to_cpumask; cpumask_var_t nmsk, npresmsk; + int ret = -ENOMEM; if (!zalloc_cpumask_var(&nmsk, GFP_KERNEL)) return ret; if (!zalloc_cpumask_var(&npresmsk, GFP_KERNEL)) - goto fail; + goto fail_nmsk; + + node_to_cpumask = alloc_node_to_cpumask(); + if (!node_to_cpumask) + goto fail_npresmsk; ret = 0; /* Stabilize the cpumasks */ @@ -217,13 +220,22 @@ static int irq_build_affinity_masks(const struct irq_affinity *affd, if (nr_present < numvecs) WARN_ON(nr_present + nr_others < numvecs); + free_node_to_cpumask(node_to_cpumask); + + fail_npresmsk: free_cpumask_var(npresmsk); - fail: + fail_nmsk: free_cpumask_var(nmsk); return ret; } +static void default_calc_sets(struct irq_affinity *affd, unsigned int affvecs) +{ + affd->nr_sets = 1; + affd->set_size[0] = affvecs; +} + /** * irq_create_affinity_masks - Create affinity masks for multiqueue spreading * @nvecs: The total number of vectors @@ -232,50 +244,62 @@ static int irq_build_affinity_masks(const struct irq_affinity *affd, * Returns the irq_affinity_desc pointer or NULL if allocation failed. */ struct irq_affinity_desc * -irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) +irq_create_affinity_masks(unsigned int nvecs, struct irq_affinity *affd) { - int affvecs = nvecs - affd->pre_vectors - affd->post_vectors; - int curvec, usedvecs; - cpumask_var_t *node_to_cpumask; + unsigned int affvecs, curvec, usedvecs, i; struct irq_affinity_desc *masks = NULL; - int i, nr_sets; /* - * If there aren't any vectors left after applying the pre/post - * vectors don't bother with assigning affinity. + * Determine the number of vectors which need interrupt affinities + * assigned. If the pre/post request exhausts the available vectors + * then nothing to do here except for invoking the calc_sets() + * callback so the device driver can adjust to the situation. If there + * is only a single vector, then managing the queue is pointless as + * well. */ - if (nvecs == affd->pre_vectors + affd->post_vectors) + if (nvecs > 1 && nvecs > affd->pre_vectors + affd->post_vectors) + affvecs = nvecs - affd->pre_vectors - affd->post_vectors; + else + affvecs = 0; + + /* + * Simple invocations do not provide a calc_sets() callback. Install + * the generic one. + */ + if (!affd->calc_sets) + affd->calc_sets = default_calc_sets; + + /* Recalculate the sets */ + affd->calc_sets(affd, affvecs); + + if (WARN_ON_ONCE(affd->nr_sets > IRQ_AFFINITY_MAX_SETS)) return NULL; - node_to_cpumask = alloc_node_to_cpumask(); - if (!node_to_cpumask) + /* Nothing to assign? */ + if (!affvecs) return NULL; masks = kcalloc(nvecs, sizeof(*masks), GFP_KERNEL); if (!masks) - goto outnodemsk; + return NULL; /* Fill out vectors at the beginning that don't need affinity */ for (curvec = 0; curvec < affd->pre_vectors; curvec++) cpumask_copy(&masks[curvec].mask, irq_default_affinity); + /* * Spread on present CPUs starting from affd->pre_vectors. If we * have multiple sets, build each sets affinity mask separately. */ - nr_sets = affd->nr_sets; - if (!nr_sets) - nr_sets = 1; - - for (i = 0, usedvecs = 0; i < nr_sets; i++) { - int this_vecs = affd->sets ? affd->sets[i] : affvecs; + for (i = 0, usedvecs = 0; i < affd->nr_sets; i++) { + unsigned int this_vecs = affd->set_size[i]; int ret; ret = irq_build_affinity_masks(affd, curvec, this_vecs, - curvec, node_to_cpumask, masks); + curvec, masks); if (ret) { kfree(masks); - masks = NULL; - goto outnodemsk; + return NULL; } curvec += this_vecs; usedvecs += this_vecs; @@ -293,8 +317,6 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) for (i = affd->pre_vectors; i < nvecs - affd->post_vectors; i++) masks[i].is_managed = 1; -outnodemsk: - free_node_to_cpumask(node_to_cpumask); return masks; } @@ -304,25 +326,22 @@ outnodemsk: * @maxvec: The maximum number of vectors available * @affd: Description of the affinity requirements */ -int irq_calc_affinity_vectors(int minvec, int maxvec, const struct irq_affinity *affd) +unsigned int irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec, + const struct irq_affinity *affd) { - int resv = affd->pre_vectors + affd->post_vectors; - int vecs = maxvec - resv; - int set_vecs; + unsigned int resv = affd->pre_vectors + affd->post_vectors; + unsigned int set_vecs; if (resv > minvec) return 0; - if (affd->nr_sets) { - int i; - - for (i = 0, set_vecs = 0; i < affd->nr_sets; i++) - set_vecs += affd->sets[i]; + if (affd->calc_sets) { + set_vecs = maxvec - resv; } else { get_online_cpus(); set_vecs = cpumask_weight(cpu_possible_mask); put_online_cpus(); } - return resv + min(set_vecs, vecs); + return resv + min(set_vecs, maxvec - resv); } diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 34e969069488..99b7dd6982a4 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -730,6 +730,37 @@ out: EXPORT_SYMBOL_GPL(handle_fasteoi_irq); /** + * handle_fasteoi_nmi - irq handler for NMI interrupt lines + * @desc: the interrupt description structure for this irq + * + * A simple NMI-safe handler, considering the restrictions + * from request_nmi. + * + * Only a single callback will be issued to the chip: an ->eoi() + * call when the interrupt has been serviced. This enables support + * for modern forms of interrupt handlers, which handle the flow + * details in hardware, transparently. + */ +void handle_fasteoi_nmi(struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + struct irqaction *action = desc->action; + unsigned int irq = irq_desc_get_irq(desc); + irqreturn_t res; + + trace_irq_handler_entry(irq, action); + /* + * NMIs cannot be shared, there is only one action. + */ + res = action->handler(irq, action->dev_id); + trace_irq_handler_exit(irq, action, res); + + if (chip->irq_eoi) + chip->irq_eoi(&desc->irq_data); +} +EXPORT_SYMBOL_GPL(handle_fasteoi_nmi); + +/** * handle_edge_irq - edge type IRQ handler * @desc: the interrupt description structure for this irq * @@ -855,7 +886,11 @@ void handle_percpu_irq(struct irq_desc *desc) { struct irq_chip *chip = irq_desc_get_chip(desc); - kstat_incr_irqs_this_cpu(desc); + /* + * PER CPU interrupts are not serialized. Do not touch + * desc->tot_count. + */ + __kstat_incr_irqs_this_cpu(desc); if (chip->irq_ack) chip->irq_ack(&desc->irq_data); @@ -884,7 +919,11 @@ void handle_percpu_devid_irq(struct irq_desc *desc) unsigned int irq = irq_desc_get_irq(desc); irqreturn_t res; - kstat_incr_irqs_this_cpu(desc); + /* + * PER CPU interrupts are not serialized. Do not touch + * desc->tot_count. + */ + __kstat_incr_irqs_this_cpu(desc); if (chip->irq_ack) chip->irq_ack(&desc->irq_data); @@ -908,6 +947,29 @@ void handle_percpu_devid_irq(struct irq_desc *desc) chip->irq_eoi(&desc->irq_data); } +/** + * handle_percpu_devid_fasteoi_nmi - Per CPU local NMI handler with per cpu + * dev ids + * @desc: the interrupt description structure for this irq + * + * Similar to handle_fasteoi_nmi, but handling the dev_id cookie + * as a percpu pointer. + */ +void handle_percpu_devid_fasteoi_nmi(struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + struct irqaction *action = desc->action; + unsigned int irq = irq_desc_get_irq(desc); + irqreturn_t res; + + trace_irq_handler_entry(irq, action); + res = action->handler(irq, raw_cpu_ptr(action->percpu_dev_id)); + trace_irq_handler_exit(irq, action, res); + + if (chip->irq_eoi) + chip->irq_eoi(&desc->irq_data); +} + static void __irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle, int is_chained, const char *name) diff --git a/kernel/irq/debugfs.c b/kernel/irq/debugfs.c index 6f636136cccc..516c00a5e867 100644 --- a/kernel/irq/debugfs.c +++ b/kernel/irq/debugfs.c @@ -56,6 +56,7 @@ static const struct irq_bit_descr irqchip_flags[] = { BIT_MASK_DESCR(IRQCHIP_ONESHOT_SAFE), BIT_MASK_DESCR(IRQCHIP_EOI_THREADED), BIT_MASK_DESCR(IRQCHIP_SUPPORTS_LEVEL_MSI), + BIT_MASK_DESCR(IRQCHIP_SUPPORTS_NMI), }; static void @@ -140,6 +141,7 @@ static const struct irq_bit_descr irqdesc_istates[] = { BIT_MASK_DESCR(IRQS_WAITING), BIT_MASK_DESCR(IRQS_PENDING), BIT_MASK_DESCR(IRQS_SUSPENDED), + BIT_MASK_DESCR(IRQS_NMI), }; @@ -203,8 +205,8 @@ static ssize_t irq_debug_write(struct file *file, const char __user *user_buf, chip_bus_lock(desc); raw_spin_lock_irqsave(&desc->lock, flags); - if (irq_settings_is_level(desc)) { - /* Can't do level, sorry */ + if (irq_settings_is_level(desc) || desc->istate & IRQS_NMI) { + /* Can't do level nor NMIs, sorry */ err = -EINVAL; } else { desc->istate |= IRQS_PENDING; @@ -256,8 +258,6 @@ static int __init irq_debugfs_init(void) int irq; root_dir = debugfs_create_dir("irq", NULL); - if (!root_dir) - return -ENOMEM; irq_domain_debugfs_init(root_dir); diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c index 38554bc35375..6df5ddfdb0f8 100644 --- a/kernel/irq/handle.c +++ b/kernel/irq/handle.c @@ -166,7 +166,7 @@ irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc, unsigned int *flags __irq_wake_thread(desc, action); - /* Fall through to add to randomness */ + /* Fall through - to add to randomness */ case IRQ_HANDLED: *flags |= action->flags; break; diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index ca6afa267070..70c3053bc1f6 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -49,6 +49,7 @@ enum { * IRQS_WAITING - irq is waiting * IRQS_PENDING - irq is pending and replayed later * IRQS_SUSPENDED - irq is suspended + * IRQS_NMI - irq line is used to deliver NMIs */ enum { IRQS_AUTODETECT = 0x00000001, @@ -60,6 +61,7 @@ enum { IRQS_PENDING = 0x00000200, IRQS_SUSPENDED = 0x00000800, IRQS_TIMINGS = 0x00001000, + IRQS_NMI = 0x00002000, }; #include "debug.h" @@ -242,12 +244,18 @@ static inline void irq_state_set_masked(struct irq_desc *desc) #undef __irqd_to_state -static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc) +static inline void __kstat_incr_irqs_this_cpu(struct irq_desc *desc) { __this_cpu_inc(*desc->kstat_irqs); __this_cpu_inc(kstat.irqs_sum); } +static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc) +{ + __kstat_incr_irqs_this_cpu(desc); + desc->tot_count++; +} + static inline int irq_desc_get_node(struct irq_desc *desc) { return irq_common_data_get_node(&desc->irq_common_data); diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index ef8ad36cadcf..13539e12cd80 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -119,6 +119,7 @@ static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node, desc->depth = 1; desc->irq_count = 0; desc->irqs_unhandled = 0; + desc->tot_count = 0; desc->name = NULL; desc->owner = owner; for_each_possible_cpu(cpu) @@ -669,6 +670,41 @@ int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq, set_irq_regs(old_regs); return ret; } + +#ifdef CONFIG_IRQ_DOMAIN +/** + * handle_domain_nmi - Invoke the handler for a HW irq belonging to a domain + * @domain: The domain where to perform the lookup + * @hwirq: The HW irq number to convert to a logical one + * @regs: Register file coming from the low-level handling code + * + * Returns: 0 on success, or -EINVAL if conversion has failed + */ +int handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq, + struct pt_regs *regs) +{ + struct pt_regs *old_regs = set_irq_regs(regs); + unsigned int irq; + int ret = 0; + + nmi_enter(); + + irq = irq_find_mapping(domain, hwirq); + + /* + * ack_bad_irq is not NMI-safe, just report + * an invalid interrupt. + */ + if (likely(irq)) + generic_handle_irq(irq); + else + ret = -EINVAL; + + nmi_exit(); + set_irq_regs(old_regs); + return ret; +} +#endif #endif /* Dynamic interrupt handling */ @@ -919,11 +955,15 @@ unsigned int kstat_irqs_cpu(unsigned int irq, int cpu) unsigned int kstat_irqs(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); - int cpu; unsigned int sum = 0; + int cpu; if (!desc || !desc->kstat_irqs) return 0; + if (!irq_settings_is_per_cpu_devid(desc) && + !irq_settings_is_per_cpu(desc)) + return desc->tot_count; + for_each_possible_cpu(cpu) sum += *per_cpu_ptr(desc->kstat_irqs, cpu); return sum; diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 8b0be4bd6565..3bf9793d8825 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -458,6 +458,20 @@ void irq_set_default_host(struct irq_domain *domain) } EXPORT_SYMBOL_GPL(irq_set_default_host); +/** + * irq_get_default_host() - Retrieve the "default" irq domain + * + * Returns: the default domain, if any. + * + * Modern code should never use this. This should only be used on + * systems that cannot implement a firmware->fwnode mapping (which + * both DT and ACPI provide). + */ +struct irq_domain *irq_get_default_host(void) +{ + return irq_default_domain; +} + static void irq_domain_clear_mapping(struct irq_domain *domain, irq_hw_number_t hwirq) { @@ -1749,8 +1763,6 @@ void __init irq_domain_debugfs_init(struct dentry *root) struct irq_domain *d; domain_dir = debugfs_create_dir("domains", root); - if (!domain_dir) - return; debugfs_create_file("default", 0444, domain_dir, NULL, &irq_domain_debug_fops); diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 84b54a17b95d..9ec34a2a6638 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -341,7 +341,7 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify) /* The release function is promised process context */ might_sleep(); - if (!desc) + if (!desc || desc->istate & IRQS_NMI) return -EINVAL; /* Complete initialisation of *notify */ @@ -553,6 +553,21 @@ bool disable_hardirq(unsigned int irq) } EXPORT_SYMBOL_GPL(disable_hardirq); +/** + * disable_nmi_nosync - disable an nmi without waiting + * @irq: Interrupt to disable + * + * Disable the selected interrupt line. Disables and enables are + * nested. + * The interrupt to disable must have been requested through request_nmi. + * Unlike disable_nmi(), this function does not ensure existing + * instances of the IRQ handler have completed before returning. + */ +void disable_nmi_nosync(unsigned int irq) +{ + disable_irq_nosync(irq); +} + void __enable_irq(struct irq_desc *desc) { switch (desc->depth) { @@ -609,6 +624,20 @@ out: } EXPORT_SYMBOL(enable_irq); +/** + * enable_nmi - enable handling of an nmi + * @irq: Interrupt to enable + * + * The interrupt to enable must have been requested through request_nmi. + * Undoes the effect of one call to disable_nmi(). If this + * matches the last disable, processing of interrupts on this + * IRQ line is re-enabled. + */ +void enable_nmi(unsigned int irq) +{ + enable_irq(irq); +} + static int set_irq_wake_real(unsigned int irq, unsigned int on) { struct irq_desc *desc = irq_to_desc(irq); @@ -644,6 +673,12 @@ int irq_set_irq_wake(unsigned int irq, unsigned int on) if (!desc) return -EINVAL; + /* Don't use NMIs as wake up interrupts please */ + if (desc->istate & IRQS_NMI) { + ret = -EINVAL; + goto out_unlock; + } + /* wakeup-capable irqs can be shared between drivers that * don't need to have the same sleep mode behaviors. */ @@ -666,6 +701,8 @@ int irq_set_irq_wake(unsigned int irq, unsigned int on) irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE); } } + +out_unlock: irq_put_desc_busunlock(desc, flags); return ret; } @@ -726,6 +763,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned long flags) case IRQ_SET_MASK_OK_DONE: irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK); irqd_set(&desc->irq_data, flags); + /* fall through */ case IRQ_SET_MASK_OK_NOCOPY: flags = irqd_get_trigger_type(&desc->irq_data); @@ -1128,6 +1166,39 @@ static void irq_release_resources(struct irq_desc *desc) c->irq_release_resources(d); } +static bool irq_supports_nmi(struct irq_desc *desc) +{ + struct irq_data *d = irq_desc_get_irq_data(desc); + +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY + /* Only IRQs directly managed by the root irqchip can be set as NMI */ + if (d->parent_data) + return false; +#endif + /* Don't support NMIs for chips behind a slow bus */ + if (d->chip->irq_bus_lock || d->chip->irq_bus_sync_unlock) + return false; + + return d->chip->flags & IRQCHIP_SUPPORTS_NMI; +} + +static int irq_nmi_setup(struct irq_desc *desc) +{ + struct irq_data *d = irq_desc_get_irq_data(desc); + struct irq_chip *c = d->chip; + + return c->irq_nmi_setup ? c->irq_nmi_setup(d) : -EINVAL; +} + +static void irq_nmi_teardown(struct irq_desc *desc) +{ + struct irq_data *d = irq_desc_get_irq_data(desc); + struct irq_chip *c = d->chip; + + if (c->irq_nmi_teardown) + c->irq_nmi_teardown(d); +} + static int setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary) { @@ -1302,9 +1373,17 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) * fields must have IRQF_SHARED set and the bits which * set the trigger type must match. Also all must * agree on ONESHOT. + * Interrupt lines used for NMIs cannot be shared. */ unsigned int oldtype; + if (desc->istate & IRQS_NMI) { + pr_err("Invalid attempt to share NMI for %s (irq %d) on irqchip %s.\n", + new->name, irq, desc->irq_data.chip->name); + ret = -EINVAL; + goto out_unlock; + } + /* * If nobody did set the configuration before, inherit * the one provided by the requester. @@ -1756,6 +1835,59 @@ const void *free_irq(unsigned int irq, void *dev_id) } EXPORT_SYMBOL(free_irq); +/* This function must be called with desc->lock held */ +static const void *__cleanup_nmi(unsigned int irq, struct irq_desc *desc) +{ + const char *devname = NULL; + + desc->istate &= ~IRQS_NMI; + + if (!WARN_ON(desc->action == NULL)) { + irq_pm_remove_action(desc, desc->action); + devname = desc->action->name; + unregister_handler_proc(irq, desc->action); + + kfree(desc->action); + desc->action = NULL; + } + + irq_settings_clr_disable_unlazy(desc); + irq_shutdown(desc); + + irq_release_resources(desc); + + irq_chip_pm_put(&desc->irq_data); + module_put(desc->owner); + + return devname; +} + +const void *free_nmi(unsigned int irq, void *dev_id) +{ + struct irq_desc *desc = irq_to_desc(irq); + unsigned long flags; + const void *devname; + + if (!desc || WARN_ON(!(desc->istate & IRQS_NMI))) + return NULL; + + if (WARN_ON(irq_settings_is_per_cpu_devid(desc))) + return NULL; + + /* NMI still enabled */ + if (WARN_ON(desc->depth == 0)) + disable_nmi_nosync(irq); + + raw_spin_lock_irqsave(&desc->lock, flags); + + irq_nmi_teardown(desc); + devname = __cleanup_nmi(irq, desc); + + raw_spin_unlock_irqrestore(&desc->lock, flags); + + return devname; +} + /** * request_threaded_irq - allocate an interrupt line * @irq: Interrupt line to allocate @@ -1925,6 +2057,101 @@ int request_any_context_irq(unsigned int irq, irq_handler_t handler, } EXPORT_SYMBOL_GPL(request_any_context_irq); +/** + * request_nmi - allocate an interrupt line for NMI delivery + * @irq: Interrupt line to allocate + * @handler: Function to be called when the IRQ occurs. + * Threaded handler for threaded interrupts. + * @irqflags: Interrupt type flags + * @name: An ascii name for the claiming device + * @dev_id: A cookie passed back to the handler function + * + * This call allocates interrupt resources and enables the + * interrupt line and IRQ handling. It sets up the IRQ line + * to be handled as an NMI. + * + * An interrupt line delivering NMIs cannot be shared and IRQ handling + * cannot be threaded. + * + * Interrupt lines requested for NMI delivering must produce per cpu + * interrupts and have auto enabling setting disabled. + * + * Dev_id must be globally unique. Normally the address of the + * device data structure is used as the cookie. Since the handler + * receives this value it makes sense to use it. + * + * If the interrupt line cannot be used to deliver NMIs, function + * will fail and return a negative value. + */ +int request_nmi(unsigned int irq, irq_handler_t handler, + unsigned long irqflags, const char *name, void *dev_id) +{ + struct irqaction *action; + struct irq_desc *desc; + unsigned long flags; + int retval; + + if (irq == IRQ_NOTCONNECTED) + return -ENOTCONN; + + /* NMI cannot be shared, used for Polling */ + if (irqflags & (IRQF_SHARED | IRQF_COND_SUSPEND | IRQF_IRQPOLL)) + return -EINVAL; + + if (!(irqflags & IRQF_PERCPU)) + return -EINVAL; + + if (!handler) + return -EINVAL; + + desc = irq_to_desc(irq); + + if (!desc || irq_settings_can_autoenable(desc) || + !irq_settings_can_request(desc) || + WARN_ON(irq_settings_is_per_cpu_devid(desc)) || + !irq_supports_nmi(desc)) + return -EINVAL; + + action = kzalloc(sizeof(struct irqaction), GFP_KERNEL); + if (!action) + return -ENOMEM; + + action->handler = handler; + action->flags = irqflags | IRQF_NO_THREAD | IRQF_NOBALANCING; + action->name = name; + action->dev_id = dev_id; + + retval = irq_chip_pm_get(&desc->irq_data); + if (retval < 0) + goto err_out; + + retval = __setup_irq(irq, desc, action); + if (retval) + goto err_irq_setup; + + raw_spin_lock_irqsave(&desc->lock, flags); + + /* Setup NMI state */ + desc->istate |= IRQS_NMI; + retval = irq_nmi_setup(desc); + if (retval) { + __cleanup_nmi(irq, desc); + raw_spin_unlock_irqrestore(&desc->lock, flags); + return -EINVAL; + } + + raw_spin_unlock_irqrestore(&desc->lock, flags); + + return 0; + +err_irq_setup: + irq_chip_pm_put(&desc->irq_data); +err_out: + kfree(action); + + return retval; +} + void enable_percpu_irq(unsigned int irq, unsigned int type) { unsigned int cpu = smp_processor_id(); @@ -1959,6 +2186,11 @@ out: } EXPORT_SYMBOL_GPL(enable_percpu_irq); +void enable_percpu_nmi(unsigned int irq, unsigned int type) +{ + enable_percpu_irq(irq, type); +} + /** * irq_percpu_is_enabled - Check whether the per cpu irq is enabled * @irq: Linux irq number to check for @@ -1998,6 +2230,11 @@ void disable_percpu_irq(unsigned int irq) } EXPORT_SYMBOL_GPL(disable_percpu_irq); +void disable_percpu_nmi(unsigned int irq) +{ + disable_percpu_irq(irq); +} + /* * Internal function to unregister a percpu irqaction. */ @@ -2029,6 +2266,8 @@ static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_ /* Found it - now remove it from the list of entries: */ desc->action = NULL; + desc->istate &= ~IRQS_NMI; + raw_spin_unlock_irqrestore(&desc->lock, flags); unregister_handler_proc(irq, action); @@ -2082,6 +2321,19 @@ void free_percpu_irq(unsigned int irq, void __percpu *dev_id) } EXPORT_SYMBOL_GPL(free_percpu_irq); +void free_percpu_nmi(unsigned int irq, void __percpu *dev_id) +{ + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc || !irq_settings_is_per_cpu_devid(desc)) + return; + + if (WARN_ON(!(desc->istate & IRQS_NMI))) + return; + + kfree(__free_percpu_irq(irq, dev_id)); +} + /** * setup_percpu_irq - setup a per-cpu interrupt * @irq: Interrupt line to setup @@ -2172,6 +2424,158 @@ int __request_percpu_irq(unsigned int irq, irq_handler_t handler, EXPORT_SYMBOL_GPL(__request_percpu_irq); /** + * request_percpu_nmi - allocate a percpu interrupt line for NMI delivery + * @irq: Interrupt line to allocate + * @handler: Function to be called when the IRQ occurs. + * @name: An ascii name for the claiming device + * @dev_id: A percpu cookie passed back to the handler function + * + * This call allocates interrupt resources for a per CPU NMI. Per CPU NMIs + * have to be setup on each CPU by calling prepare_percpu_nmi() before + * being enabled on the same CPU by using enable_percpu_nmi(). + * + * Dev_id must be globally unique. It is a per-cpu variable, and + * the handler gets called with the interrupted CPU's instance of + * that variable. + * + * Interrupt lines requested for NMI delivering should have auto enabling + * setting disabled. + * + * If the interrupt line cannot be used to deliver NMIs, function + * will fail returning a negative value. + */ +int request_percpu_nmi(unsigned int irq, irq_handler_t handler, + const char *name, void __percpu *dev_id) +{ + struct irqaction *action; + struct irq_desc *desc; + unsigned long flags; + int retval; + + if (!handler) + return -EINVAL; + + desc = irq_to_desc(irq); + + if (!desc || !irq_settings_can_request(desc) || + !irq_settings_is_per_cpu_devid(desc) || + irq_settings_can_autoenable(desc) || + !irq_supports_nmi(desc)) + return -EINVAL; + + /* The line cannot already be NMI */ + if (desc->istate & IRQS_NMI) + return -EINVAL; + + action = kzalloc(sizeof(struct irqaction), GFP_KERNEL); + if (!action) + return -ENOMEM; + + action->handler = handler; + action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND | IRQF_NO_THREAD + | IRQF_NOBALANCING; + action->name = name; + action->percpu_dev_id = dev_id; + + retval = irq_chip_pm_get(&desc->irq_data); + if (retval < 0) + goto err_out; + + retval = __setup_irq(irq, desc, action); + if (retval) + goto err_irq_setup; + + raw_spin_lock_irqsave(&desc->lock, flags); + desc->istate |= IRQS_NMI; + raw_spin_unlock_irqrestore(&desc->lock, flags); + + return 0; + +err_irq_setup: + irq_chip_pm_put(&desc->irq_data); +err_out: + kfree(action); + + return retval; +} + +/** + * prepare_percpu_nmi - performs CPU local setup for NMI delivery + * @irq: Interrupt line to prepare for NMI delivery + * + * This call prepares an interrupt line to deliver NMI on the current CPU, + * before that interrupt line gets enabled with enable_percpu_nmi(). + * + * As a CPU local operation, this should be called from non-preemptible + * context. + * + * If the interrupt line cannot be used to deliver NMIs, function + * will fail returning a negative value. + */ +int prepare_percpu_nmi(unsigned int irq) +{ + unsigned long flags; + struct irq_desc *desc; + int ret = 0; + + WARN_ON(preemptible()); + + desc = irq_get_desc_lock(irq, &flags, + IRQ_GET_DESC_CHECK_PERCPU); + if (!desc) + return -EINVAL; + + if (WARN(!(desc->istate & IRQS_NMI), + KERN_ERR "prepare_percpu_nmi called for a non-NMI interrupt: irq %u\n", + irq)) { + ret = -EINVAL; + goto out; + } + + ret = irq_nmi_setup(desc); + if (ret) { + pr_err("Failed to setup NMI delivery: irq %u\n", irq); + goto out; + } + +out: + irq_put_desc_unlock(desc, flags); + return ret; +} + +/** + * teardown_percpu_nmi - undoes NMI setup of IRQ line + * @irq: Interrupt line from which CPU local NMI configuration should be + * removed + * + * This call undoes the setup done by prepare_percpu_nmi(). + * + * IRQ line should not be enabled for the current CPU. + * + * As a CPU local operation, this should be called from non-preemptible + * context. + */ +void teardown_percpu_nmi(unsigned int irq) +{ + unsigned long flags; + struct irq_desc *desc; + + WARN_ON(preemptible()); + + desc = irq_get_desc_lock(irq, &flags, + IRQ_GET_DESC_CHECK_PERCPU); + if (!desc) + return; + + if (WARN_ON(!(desc->istate & IRQS_NMI))) + goto out; + + irq_nmi_teardown(desc); +out: + irq_put_desc_unlock(desc, flags); +} + +/** * irq_get_irqchip_state - returns the irqchip state of a interrupt. * @irq: Interrupt line that is forwarded to a VM * @which: One of IRQCHIP_STATE_* the caller wants to know about diff --git a/kernel/kthread.c b/kernel/kthread.c index 087d18d771b5..65234c89d85b 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -101,6 +101,12 @@ bool kthread_should_stop(void) } EXPORT_SYMBOL(kthread_should_stop); +bool __kthread_should_park(struct task_struct *k) +{ + return test_bit(KTHREAD_SHOULD_PARK, &to_kthread(k)->flags); +} +EXPORT_SYMBOL_GPL(__kthread_should_park); + /** * kthread_should_park - should this kthread park now? * @@ -114,7 +120,7 @@ EXPORT_SYMBOL(kthread_should_stop); */ bool kthread_should_park(void) { - return test_bit(KTHREAD_SHOULD_PARK, &to_kthread(current)->flags); + return __kthread_should_park(current); } EXPORT_SYMBOL_GPL(kthread_should_park); diff --git a/kernel/softirq.c b/kernel/softirq.c index d28813306b2c..10277429ed84 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -89,7 +89,8 @@ static bool ksoftirqd_running(unsigned long pending) if (pending & SOFTIRQ_NOW_MASK) return false; - return tsk && (tsk->state == TASK_RUNNING); + return tsk && (tsk->state == TASK_RUNNING) && + !__kthread_should_park(tsk); } /* |