From a648eb3a3f79e9736a59b28783700c2c691db419 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 10 Dec 2024 11:34:14 +0100 Subject: genirq: Provide IRQCHIP_MOVE_DEFERRED The logic of GENERIC_PENDING_IRQ is backwards for historical reasons. Most interrupt controllers allow to move the interrupt from arbitrary contexts. If GENERIC_PENDING_IRQ is enabled by an architecture to support a chip, which requires the affinity change to happen in interrupt context, all other chips have to be marked with IRQF_MOVE_PCNTXT. That's tedious and there is no real good reason for the extra flags in the irq descriptor and the irq data status fields. In fact the decision whether interrupts can be moved in arbitrary context or not is a property of the interrupt chip. To simplify adoption for RISC-V provide a new mechanism which is enabled via a config switch and allows to add a flag to irq_chip::flags to request that interrupt affinity changes are deferred. Setting the top level chip of an interrupt evaluates the flag and maps it into the existing logic. The config switch and the various PCNTXT flags are temporary until x86 is converted over to this scheme. This intermediate step also allows trivial backporting of the mechanism to plug the affinity change race of various RISC-V interrupt controllers. Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20241210103335.500314436@linutronix.de --- kernel/irq/chip.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'kernel/irq/chip.c') diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 271e9139de77..7989da287d4c 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -47,6 +47,13 @@ int irq_set_chip(unsigned int irq, const struct irq_chip *chip) return -EINVAL; desc->irq_data.chip = (struct irq_chip *)(chip ?: &no_irq_chip); + + if (IS_ENABLED(CONFIG_GENERIC_PENDING_IRQ_CHIPFLAGS) && chip) { + if (chip->flags & IRQCHIP_MOVE_DEFERRED) + irqd_clear(&desc->irq_data, IRQD_MOVE_PCNTXT); + else + irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT); + } irq_put_desc_unlock(desc, flags); /* * For !CONFIG_SPARSE_IRQ make the irq show up in @@ -1114,16 +1121,21 @@ void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set) trigger = irqd_get_trigger_type(&desc->irq_data); irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU | - IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT); + IRQD_TRIGGER_MASK | IRQD_LEVEL); if (irq_settings_has_no_balance_set(desc)) irqd_set(&desc->irq_data, IRQD_NO_BALANCING); if (irq_settings_is_per_cpu(desc)) irqd_set(&desc->irq_data, IRQD_PER_CPU); - if (irq_settings_can_move_pcntxt(desc)) - irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT); if (irq_settings_is_level(desc)) irqd_set(&desc->irq_data, IRQD_LEVEL); + /* Keep this around until x86 is converted over */ + if (!IS_ENABLED(CONFIG_GENERIC_PENDING_IRQ_CHIPFLAGS)) { + irqd_clear(&desc->irq_data, IRQD_MOVE_PCNTXT); + if (irq_settings_can_move_pcntxt(desc)) + irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT); + } + tmp = irq_settings_get_trigger_mask(desc); if (tmp != IRQ_TYPE_NONE) trigger = tmp; -- cgit v1.2.3 From f94a18249b7f9131f3ca8eacf07f21050747ebd7 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 10 Dec 2024 11:34:17 +0100 Subject: genirq: Remove IRQ_MOVE_PCNTXT and related code Now that x86 is converted over to use the IRQCHIP_MOVE_DEFERRED flags, remove IRQ*_MOVE_PCNTXT and related code. Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20241210103335.626707225@linutronix.de --- arch/x86/Kconfig | 1 - include/linux/irq.h | 12 +----------- kernel/irq/chip.c | 14 -------------- kernel/irq/debugfs.c | 1 - kernel/irq/internals.h | 2 +- kernel/irq/settings.h | 6 ------ 6 files changed, 2 insertions(+), 34 deletions(-) (limited to 'kernel/irq/chip.c') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index df0fd72dc9c5..9d7bd0ae48c4 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -173,7 +173,6 @@ config X86 select GENERIC_IRQ_RESERVATION_MODE select GENERIC_IRQ_SHOW select GENERIC_PENDING_IRQ if SMP - select GENERIC_PENDING_IRQ_CHIPFLAGS if SMP select GENERIC_PTDUMP select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL diff --git a/include/linux/irq.h b/include/linux/irq.h index 6e021548fa0a..8daa17f0107a 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -64,7 +64,6 @@ enum irqchip_irq_state; * IRQ_NOAUTOEN - Interrupt is not automatically enabled in * request/setup_irq() * IRQ_NO_BALANCING - Interrupt cannot be balanced (affinity set) - * IRQ_MOVE_PCNTXT - Interrupt can be migrated from process context * IRQ_NESTED_THREAD - Interrupt nests into another thread * IRQ_PER_CPU_DEVID - Dev_id is a per-cpu variable * IRQ_IS_POLLED - Always polled by another interrupt. Exclude @@ -93,7 +92,6 @@ enum { IRQ_NOREQUEST = (1 << 11), IRQ_NOAUTOEN = (1 << 12), IRQ_NO_BALANCING = (1 << 13), - IRQ_MOVE_PCNTXT = (1 << 14), IRQ_NESTED_THREAD = (1 << 15), IRQ_NOTHREAD = (1 << 16), IRQ_PER_CPU_DEVID = (1 << 17), @@ -105,7 +103,7 @@ enum { #define IRQF_MODIFY_MASK \ (IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \ - IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \ + IRQ_NOAUTOEN | IRQ_LEVEL | IRQ_NO_BALANCING | \ IRQ_PER_CPU | IRQ_NESTED_THREAD | IRQ_NOTHREAD | IRQ_PER_CPU_DEVID | \ IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY | IRQ_HIDDEN) @@ -201,8 +199,6 @@ struct irq_data { * IRQD_LEVEL - Interrupt is level triggered * IRQD_WAKEUP_STATE - Interrupt is configured for wakeup * from suspend - * IRQD_MOVE_PCNTXT - Interrupt can be moved in process - * context * IRQD_IRQ_DISABLED - Disabled state of the interrupt * IRQD_IRQ_MASKED - Masked state of the interrupt * IRQD_IRQ_INPROGRESS - In progress state of the interrupt @@ -233,7 +229,6 @@ enum { IRQD_AFFINITY_SET = BIT(12), IRQD_LEVEL = BIT(13), IRQD_WAKEUP_STATE = BIT(14), - IRQD_MOVE_PCNTXT = BIT(15), IRQD_IRQ_DISABLED = BIT(16), IRQD_IRQ_MASKED = BIT(17), IRQD_IRQ_INPROGRESS = BIT(18), @@ -338,11 +333,6 @@ static inline bool irqd_is_wakeup_set(struct irq_data *d) return __irqd_to_state(d) & IRQD_WAKEUP_STATE; } -static inline bool irqd_can_move_in_process_context(struct irq_data *d) -{ - return __irqd_to_state(d) & IRQD_MOVE_PCNTXT; -} - static inline bool irqd_irq_disabled(struct irq_data *d) { return __irqd_to_state(d) & IRQD_IRQ_DISABLED; diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 7989da287d4c..c901436ebd9f 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -47,13 +47,6 @@ int irq_set_chip(unsigned int irq, const struct irq_chip *chip) return -EINVAL; desc->irq_data.chip = (struct irq_chip *)(chip ?: &no_irq_chip); - - if (IS_ENABLED(CONFIG_GENERIC_PENDING_IRQ_CHIPFLAGS) && chip) { - if (chip->flags & IRQCHIP_MOVE_DEFERRED) - irqd_clear(&desc->irq_data, IRQD_MOVE_PCNTXT); - else - irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT); - } irq_put_desc_unlock(desc, flags); /* * For !CONFIG_SPARSE_IRQ make the irq show up in @@ -1129,13 +1122,6 @@ void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set) if (irq_settings_is_level(desc)) irqd_set(&desc->irq_data, IRQD_LEVEL); - /* Keep this around until x86 is converted over */ - if (!IS_ENABLED(CONFIG_GENERIC_PENDING_IRQ_CHIPFLAGS)) { - irqd_clear(&desc->irq_data, IRQD_MOVE_PCNTXT); - if (irq_settings_can_move_pcntxt(desc)) - irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT); - } - tmp = irq_settings_get_trigger_mask(desc); if (tmp != IRQ_TYPE_NONE) trigger = tmp; diff --git a/kernel/irq/debugfs.c b/kernel/irq/debugfs.c index 975eb8d68168..ca142b9a4db3 100644 --- a/kernel/irq/debugfs.c +++ b/kernel/irq/debugfs.c @@ -109,7 +109,6 @@ static const struct irq_bit_descr irqdata_states[] = { BIT_MASK_DESCR(IRQD_NO_BALANCING), BIT_MASK_DESCR(IRQD_SINGLE_TARGET), - BIT_MASK_DESCR(IRQD_MOVE_PCNTXT), BIT_MASK_DESCR(IRQD_AFFINITY_SET), BIT_MASK_DESCR(IRQD_SETAFFINITY_PENDING), BIT_MASK_DESCR(IRQD_AFFINITY_MANAGED), diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index b61fc64c3484..a979523640d0 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -421,7 +421,7 @@ irq_init_generic_chip(struct irq_chip_generic *gc, const char *name, #ifdef CONFIG_GENERIC_PENDING_IRQ static inline bool irq_can_move_pcntxt(struct irq_data *data) { - return irqd_can_move_in_process_context(data); + return !(data->chip->flags & IRQCHIP_MOVE_DEFERRED); } static inline bool irq_move_pending(struct irq_data *data) { diff --git a/kernel/irq/settings.h b/kernel/irq/settings.h index 7b7efb1a114b..00b3bd127692 100644 --- a/kernel/irq/settings.h +++ b/kernel/irq/settings.h @@ -11,7 +11,6 @@ enum { _IRQ_NOREQUEST = IRQ_NOREQUEST, _IRQ_NOTHREAD = IRQ_NOTHREAD, _IRQ_NOAUTOEN = IRQ_NOAUTOEN, - _IRQ_MOVE_PCNTXT = IRQ_MOVE_PCNTXT, _IRQ_NO_BALANCING = IRQ_NO_BALANCING, _IRQ_NESTED_THREAD = IRQ_NESTED_THREAD, _IRQ_PER_CPU_DEVID = IRQ_PER_CPU_DEVID, @@ -142,11 +141,6 @@ static inline void irq_settings_set_noprobe(struct irq_desc *desc) desc->status_use_accessors |= _IRQ_NOPROBE; } -static inline bool irq_settings_can_move_pcntxt(struct irq_desc *desc) -{ - return desc->status_use_accessors & _IRQ_MOVE_PCNTXT; -} - static inline bool irq_settings_can_autoenable(struct irq_desc *desc) { return !(desc->status_use_accessors & _IRQ_NOAUTOEN); -- cgit v1.2.3