diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/irq/Kconfig | 11 | ||||
| -rw-r--r-- | kernel/irq/Makefile | 1 | ||||
| -rw-r--r-- | kernel/irq/chip.c | 72 | ||||
| -rw-r--r-- | kernel/irq/internals.h | 6 | ||||
| -rw-r--r-- | kernel/irq/irq_test.c | 229 | ||||
| -rw-r--r-- | kernel/irq/pm.c | 16 | ||||
| -rw-r--r-- | kernel/irq/spurious.c | 37 |
7 files changed, 313 insertions, 59 deletions
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 3f02a0e45254..1da5e9d9da71 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -144,6 +144,17 @@ config GENERIC_IRQ_DEBUGFS config GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD bool +config IRQ_KUNIT_TEST + bool "KUnit tests for IRQ management APIs" if !KUNIT_ALL_TESTS + depends on KUNIT=y + default KUNIT_ALL_TESTS + imply SMP + help + This option enables KUnit tests for the IRQ subsystem API. These are + only for development and testing, not for regular kernel use cases. + + If unsure, say N. + endmenu config GENERIC_IRQ_MULTI_HANDLER diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile index c0f44c06d69d..6ab3a4055667 100644 --- a/kernel/irq/Makefile +++ b/kernel/irq/Makefile @@ -19,3 +19,4 @@ obj-$(CONFIG_GENERIC_IRQ_IPI_MUX) += ipi-mux.o obj-$(CONFIG_SMP) += affinity.o obj-$(CONFIG_GENERIC_IRQ_DEBUGFS) += debugfs.o obj-$(CONFIG_GENERIC_IRQ_MATRIX_ALLOCATOR) += matrix.o +obj-$(CONFIG_IRQ_KUNIT_TEST) += irq_test.o diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 2b274007e8ba..624106e886ad 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -457,22 +457,33 @@ void unmask_threaded_irq(struct irq_desc *desc) unmask_irq(desc); } -static bool irq_check_poll(struct irq_desc *desc) -{ - if (!(desc->istate & IRQS_POLL_INPROGRESS)) - return false; - return irq_wait_for_poll(desc); +/* Busy wait until INPROGRESS is cleared */ +static bool irq_wait_on_inprogress(struct irq_desc *desc) +{ + if (IS_ENABLED(CONFIG_SMP)) { + do { + raw_spin_unlock(&desc->lock); + while (irqd_irq_inprogress(&desc->irq_data)) + cpu_relax(); + raw_spin_lock(&desc->lock); + } while (irqd_irq_inprogress(&desc->irq_data)); + + /* Might have been disabled in meantime */ + return !irqd_irq_disabled(&desc->irq_data) && desc->action; + } + return false; } static bool irq_can_handle_pm(struct irq_desc *desc) { - unsigned int mask = IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED; + struct irq_data *irqd = &desc->irq_data; + const struct cpumask *aff; /* * If the interrupt is not in progress and is not an armed * wakeup interrupt, proceed. */ - if (!irqd_has_set(&desc->irq_data, mask)) + if (!irqd_has_set(irqd, IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED)) return true; /* @@ -480,13 +491,54 @@ static bool irq_can_handle_pm(struct irq_desc *desc) * and suspended, disable it and notify the pm core about the * event. */ - if (irq_pm_check_wakeup(desc)) + if (unlikely(irqd_has_set(irqd, IRQD_WAKEUP_ARMED))) { + irq_pm_handle_wakeup(desc); + return false; + } + + /* Check whether the interrupt is polled on another CPU */ + if (unlikely(desc->istate & IRQS_POLL_INPROGRESS)) { + if (WARN_ONCE(irq_poll_cpu == smp_processor_id(), + "irq poll in progress on cpu %d for irq %d\n", + smp_processor_id(), desc->irq_data.irq)) + return false; + return irq_wait_on_inprogress(desc); + } + + /* The below works only for single target interrupts */ + if (!IS_ENABLED(CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK) || + !irqd_is_single_target(irqd) || desc->handle_irq != handle_edge_irq) return false; /* - * Handle a potential concurrent poll on a different core. + * If the interrupt affinity was moved to this CPU and the + * interrupt is currently handled on the previous target CPU, then + * busy wait for INPROGRESS to be cleared. Otherwise for edge type + * interrupts the handler might get stuck on the previous target: + * + * CPU 0 CPU 1 (new target) + * handle_edge_irq() + * repeat: + * handle_event() handle_edge_irq() + * if (INPROGESS) { + * set(PENDING); + * mask(); + * return; + * } + * if (PENDING) { + * clear(PENDING); + * unmask(); + * goto repeat; + * } + * + * This happens when the device raises interrupts with a high rate + * and always before handle_event() completes and the CPU0 handler + * can clear INPROGRESS. This has been observed in virtual machines. */ - return irq_check_poll(desc); + aff = irq_data_get_effective_affinity_mask(irqd); + if (cpumask_first(aff) != smp_processor_id()) + return false; + return irq_wait_on_inprogress(desc); } static inline bool irq_can_handle_actions(struct irq_desc *desc) diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index aebfe225c9a6..0164ca48da59 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -20,6 +20,7 @@ #define istate core_internal_state__do_not_mess_with_it extern bool noirqdebug; +extern int irq_poll_cpu; extern struct irqaction chained_action; @@ -112,7 +113,6 @@ irqreturn_t handle_irq_event(struct irq_desc *desc); int check_irq_resend(struct irq_desc *desc, bool inject); void clear_irq_resend(struct irq_desc *desc); void irq_resend_init(struct irq_desc *desc); -bool irq_wait_for_poll(struct irq_desc *desc); void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action); void wake_threads_waitq(struct irq_desc *desc); @@ -277,11 +277,11 @@ static inline bool irq_is_nmi(struct irq_desc *desc) } #ifdef CONFIG_PM_SLEEP -bool irq_pm_check_wakeup(struct irq_desc *desc); +void irq_pm_handle_wakeup(struct irq_desc *desc); void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action); void irq_pm_remove_action(struct irq_desc *desc, struct irqaction *action); #else -static inline bool irq_pm_check_wakeup(struct irq_desc *desc) { return false; } +static inline void irq_pm_handle_wakeup(struct irq_desc *desc) { } static inline void irq_pm_install_action(struct irq_desc *desc, struct irqaction *action) { } static inline void diff --git a/kernel/irq/irq_test.c b/kernel/irq/irq_test.c new file mode 100644 index 000000000000..5161b56a12f9 --- /dev/null +++ b/kernel/irq/irq_test.c @@ -0,0 +1,229 @@ +// SPDX-License-Identifier: LGPL-2.1+ + +#include <linux/cpu.h> +#include <linux/cpumask.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqdesc.h> +#include <linux/irqdomain.h> +#include <linux/nodemask.h> +#include <kunit/test.h> + +#include "internals.h" + +static irqreturn_t noop_handler(int irq, void *data) +{ + return IRQ_HANDLED; +} + +static void noop(struct irq_data *data) { } +static unsigned int noop_ret(struct irq_data *data) { return 0; } + +static int noop_affinity(struct irq_data *data, const struct cpumask *dest, + bool force) +{ + irq_data_update_effective_affinity(data, dest); + + return 0; +} + +static struct irq_chip fake_irq_chip = { + .name = "fake", + .irq_startup = noop_ret, + .irq_shutdown = noop, + .irq_enable = noop, + .irq_disable = noop, + .irq_ack = noop, + .irq_mask = noop, + .irq_unmask = noop, + .irq_set_affinity = noop_affinity, + .flags = IRQCHIP_SKIP_SET_WAKE, +}; + +static void irq_disable_depth_test(struct kunit *test) +{ + struct irq_desc *desc; + int virq, ret; + + virq = irq_domain_alloc_descs(-1, 1, 0, NUMA_NO_NODE, NULL); + KUNIT_ASSERT_GE(test, virq, 0); + + irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq); + + desc = irq_to_desc(virq); + KUNIT_ASSERT_PTR_NE(test, desc, NULL); + + ret = request_irq(virq, noop_handler, 0, "test_irq", NULL); + KUNIT_EXPECT_EQ(test, ret, 0); + + KUNIT_EXPECT_EQ(test, desc->depth, 0); + + disable_irq(virq); + KUNIT_EXPECT_EQ(test, desc->depth, 1); + + enable_irq(virq); + KUNIT_EXPECT_EQ(test, desc->depth, 0); + + free_irq(virq, NULL); +} + +static void irq_free_disabled_test(struct kunit *test) +{ + struct irq_desc *desc; + int virq, ret; + + virq = irq_domain_alloc_descs(-1, 1, 0, NUMA_NO_NODE, NULL); + KUNIT_ASSERT_GE(test, virq, 0); + + irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq); + + desc = irq_to_desc(virq); + KUNIT_ASSERT_PTR_NE(test, desc, NULL); + + ret = request_irq(virq, noop_handler, 0, "test_irq", NULL); + KUNIT_EXPECT_EQ(test, ret, 0); + + KUNIT_EXPECT_EQ(test, desc->depth, 0); + + disable_irq(virq); + KUNIT_EXPECT_EQ(test, desc->depth, 1); + + free_irq(virq, NULL); + KUNIT_EXPECT_GE(test, desc->depth, 1); + + ret = request_irq(virq, noop_handler, 0, "test_irq", NULL); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, desc->depth, 0); + + free_irq(virq, NULL); +} + +static void irq_shutdown_depth_test(struct kunit *test) +{ + struct irq_desc *desc; + struct irq_data *data; + int virq, ret; + struct irq_affinity_desc affinity = { + .is_managed = 1, + .mask = CPU_MASK_ALL, + }; + + if (!IS_ENABLED(CONFIG_SMP)) + kunit_skip(test, "requires CONFIG_SMP for managed shutdown"); + + virq = irq_domain_alloc_descs(-1, 1, 0, NUMA_NO_NODE, &affinity); + KUNIT_ASSERT_GE(test, virq, 0); + + irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq); + + desc = irq_to_desc(virq); + KUNIT_ASSERT_PTR_NE(test, desc, NULL); + + data = irq_desc_get_irq_data(desc); + KUNIT_ASSERT_PTR_NE(test, data, NULL); + + ret = request_irq(virq, noop_handler, 0, "test_irq", NULL); + KUNIT_EXPECT_EQ(test, ret, 0); + + KUNIT_EXPECT_TRUE(test, irqd_is_activated(data)); + KUNIT_EXPECT_TRUE(test, irqd_is_started(data)); + KUNIT_EXPECT_TRUE(test, irqd_affinity_is_managed(data)); + + KUNIT_EXPECT_EQ(test, desc->depth, 0); + + disable_irq(virq); + KUNIT_EXPECT_EQ(test, desc->depth, 1); + + irq_shutdown_and_deactivate(desc); + + KUNIT_EXPECT_FALSE(test, irqd_is_activated(data)); + KUNIT_EXPECT_FALSE(test, irqd_is_started(data)); + + KUNIT_EXPECT_EQ(test, irq_activate(desc), 0); +#ifdef CONFIG_SMP + irq_startup_managed(desc); +#endif + + KUNIT_EXPECT_EQ(test, desc->depth, 1); + + enable_irq(virq); + KUNIT_EXPECT_EQ(test, desc->depth, 0); + + free_irq(virq, NULL); +} + +static void irq_cpuhotplug_test(struct kunit *test) +{ + struct irq_desc *desc; + struct irq_data *data; + int virq, ret; + struct irq_affinity_desc affinity = { + .is_managed = 1, + }; + + if (!IS_ENABLED(CONFIG_SMP)) + kunit_skip(test, "requires CONFIG_SMP for CPU hotplug"); + if (!get_cpu_device(1)) + kunit_skip(test, "requires more than 1 CPU for CPU hotplug"); + if (!cpu_is_hotpluggable(1)) + kunit_skip(test, "CPU 1 must be hotpluggable"); + + cpumask_copy(&affinity.mask, cpumask_of(1)); + + virq = irq_domain_alloc_descs(-1, 1, 0, NUMA_NO_NODE, &affinity); + KUNIT_ASSERT_GE(test, virq, 0); + + irq_set_chip_and_handler(virq, &fake_irq_chip, handle_simple_irq); + + desc = irq_to_desc(virq); + KUNIT_ASSERT_PTR_NE(test, desc, NULL); + + data = irq_desc_get_irq_data(desc); + KUNIT_ASSERT_PTR_NE(test, data, NULL); + + ret = request_irq(virq, noop_handler, 0, "test_irq", NULL); + KUNIT_EXPECT_EQ(test, ret, 0); + + KUNIT_EXPECT_TRUE(test, irqd_is_activated(data)); + KUNIT_EXPECT_TRUE(test, irqd_is_started(data)); + KUNIT_EXPECT_TRUE(test, irqd_affinity_is_managed(data)); + + KUNIT_EXPECT_EQ(test, desc->depth, 0); + + disable_irq(virq); + KUNIT_EXPECT_EQ(test, desc->depth, 1); + + KUNIT_EXPECT_EQ(test, remove_cpu(1), 0); + KUNIT_EXPECT_FALSE(test, irqd_is_activated(data)); + KUNIT_EXPECT_FALSE(test, irqd_is_started(data)); + KUNIT_EXPECT_GE(test, desc->depth, 1); + KUNIT_EXPECT_EQ(test, add_cpu(1), 0); + + KUNIT_EXPECT_FALSE(test, irqd_is_activated(data)); + KUNIT_EXPECT_FALSE(test, irqd_is_started(data)); + KUNIT_EXPECT_EQ(test, desc->depth, 1); + + enable_irq(virq); + KUNIT_EXPECT_TRUE(test, irqd_is_activated(data)); + KUNIT_EXPECT_TRUE(test, irqd_is_started(data)); + KUNIT_EXPECT_EQ(test, desc->depth, 0); + + free_irq(virq, NULL); +} + +static struct kunit_case irq_test_cases[] = { + KUNIT_CASE(irq_disable_depth_test), + KUNIT_CASE(irq_free_disabled_test), + KUNIT_CASE(irq_shutdown_depth_test), + KUNIT_CASE(irq_cpuhotplug_test), + {} +}; + +static struct kunit_suite irq_test_suite = { + .name = "irq_test_cases", + .test_cases = irq_test_cases, +}; + +kunit_test_suite(irq_test_suite); +MODULE_DESCRIPTION("IRQ unit test suite"); +MODULE_LICENSE("GPL"); diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c index 445912d51033..f7394729cedc 100644 --- a/kernel/irq/pm.c +++ b/kernel/irq/pm.c @@ -13,17 +13,13 @@ #include "internals.h" -bool irq_pm_check_wakeup(struct irq_desc *desc) +void irq_pm_handle_wakeup(struct irq_desc *desc) { - if (irqd_is_wakeup_armed(&desc->irq_data)) { - irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED); - desc->istate |= IRQS_SUSPENDED | IRQS_PENDING; - desc->depth++; - irq_disable(desc); - pm_system_irq_wakeup(irq_desc_get_irq(desc)); - return true; - } - return false; + irqd_clear(&desc->irq_data, IRQD_WAKEUP_ARMED); + desc->istate |= IRQS_SUSPENDED | IRQS_PENDING; + desc->depth++; + irq_disable(desc); + pm_system_irq_wakeup(irq_desc_get_irq(desc)); } /* diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c index 8f26982e7300..73280ccb74b0 100644 --- a/kernel/irq/spurious.c +++ b/kernel/irq/spurious.c @@ -19,45 +19,10 @@ static int irqfixup __read_mostly; #define POLL_SPURIOUS_IRQ_INTERVAL (HZ/10) static void poll_spurious_irqs(struct timer_list *unused); static DEFINE_TIMER(poll_spurious_irq_timer, poll_spurious_irqs); -static int irq_poll_cpu; +int irq_poll_cpu; static atomic_t irq_poll_active; /* - * We wait here for a poller to finish. - * - * If the poll runs on this CPU, then we yell loudly and return - * false. That will leave the interrupt line disabled in the worst - * case, but it should never happen. - * - * We wait until the poller is done and then recheck disabled and - * action (about to be disabled). Only if it's still active, we return - * true and let the handler run. - */ -bool irq_wait_for_poll(struct irq_desc *desc) -{ - lockdep_assert_held(&desc->lock); - - if (WARN_ONCE(irq_poll_cpu == smp_processor_id(), - "irq poll in progress on cpu %d for irq %d\n", - smp_processor_id(), desc->irq_data.irq)) - return false; - -#ifdef CONFIG_SMP - do { - raw_spin_unlock(&desc->lock); - while (irqd_irq_inprogress(&desc->irq_data)) - cpu_relax(); - raw_spin_lock(&desc->lock); - } while (irqd_irq_inprogress(&desc->irq_data)); - /* Might have been disabled in meantime */ - return !irqd_irq_disabled(&desc->irq_data) && desc->action; -#else - return false; -#endif -} - - -/* * Recovery handler for misrouted interrupts. */ static bool try_one_irq(struct irq_desc *desc, bool force) |