irq/irq_sim: try to improve the API
Subsystems (5)
v4 cover irq/irq_sim: try to improve the API
From: Bartosz Golaszewski <[email protected]>
The interrupt simulator API exposes a lot of custom data structures and functions and doesn't reuse the interfaces already exposed by the irq subsystem. This series tries to address it.
First, we make irq_domain_reset_irq_data() available to non-V2 domain API users - that'll be used in the subsequent patch. Next we overhaul the public interfaces - we hide all specific data structures and instead rely on the irq_domain struct and virtual interrupt numberspace.
The end effect is that we limit the interrupt simulator API to three functions (plus one device managed variant) and zero new structures.
v1: https://lkml.org/lkml/2019/8/12/558
v1 -> v2:
- instead of just making the new data structures opaque for users, remove them entirely in favor of irq_domain
- call irq_set_handler() & irq_domain_reset_irq_data() when unmapping the simulated interrupt
- fix a memory leak in error path
- make it possible to use irq_find_matching_fwnode() with the simulator domain
- correctly use irq_create_mapping() and irq_find_mapping(): only use the former at init-time and the latter at interrupt-time
v2 -> v3:
- drop the controverial changes to irq_domain code and only leave the changes to irq_sim and its users with the plan to revisit the former at a later time
v3 -> v4:
- add the Ack from Jonathan
- remove redundant parts of patch 1/2
Bartosz Golaszewski (2):
irq: make irq_domain_reset_irq_data() available even for non-V2 users irq/irq_sim: simplify the API
drivers/gpio/gpio-mockup.c | 47 ++++-- drivers/iio/dummy/iio_dummy_evgen.c | 32 ++-- include/linux/irq_sim.h | 34 ++--- include/linux/irqdomain.h | 2 +- kernel/irq/Kconfig | 1 + kernel/irq/irq_sim.c | 225 +++++++++++++++++----------- kernel/irq/irqdomain.c | 24 +-- 7 files changed, 215 insertions(+), 150 deletions(-)
Signature · 1 line
2.25.0
PATCH v4 1/2 irq: make irq_domain_reset_irq_data() available even for non-V2 users
From: Bartosz Golaszewski <[email protected]>
irq_domain_reset_irq_data() doesn't modify the parent data, so it can be made available even if irq domain hierarchy is not being built. We'll subsequently use it in irq_sim code.
--- include/linux/irqdomain.h | 2 +- kernel/irq/irqdomain.c | 24 ++++++++++++------------ 2 files changed, 13 insertions(+), 13 deletions(-)
include/linux/irqdomain.h +1 -1
@@ -450,6 +450,7 @@ extern void irq_domain_set_info(struct irq_domain *domain, unsigned int virq, irq_hw_number_t hwirq, struct irq_chip *chip, void *chip_data, irq_flow_handler_t handler, void *handler_data, const char *handler_name); +extern void irq_domain_reset_irq_data (struct irq_data *irq_data);#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY extern struct irq_domain *irq_domain_create_hierarchy(struct irq_domain *parent, unsigned int flags, unsigned int size,
@@ -491,7 +492,6 @@ extern int irq_domain_set_hwirq_and_chip(struct irq_domain *domain,irq_hw_number_t hwirq, struct irq_chip *chip, void *chip_data); -extern void irq_domain_reset_irq_data (struct irq_data *irq_data);extern void irq_domain_free_irqs_common (struct irq_domain *domain,unsigned int virq,unsigned int nr_irqs);
kernel/irq/irqdomain.c +12 -12
@@ -1047,6 +1047,18 @@ int irq_domain_alloc_descs(int virq, unsigned int cnt, irq_hw_number_t hwirq,return virq; } +/** +* irq_domain_reset_irq_data - Clear hwirq, chip and chip_data in @irq_data +* @irq_data: The pointer to irq_data +*/ +void irq_domain_reset_irq_data (struct irq_data *irq_data) +{ + irq_data->hwirq =0 ; + irq_data->chip = &no_irq_chip; + irq_data->chip_data =NULL ; +} +EXPORT_SYMBOL_GPL (irq_domain_reset_irq_data); +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY /** * irq_domain_create_hierarchy - Add a irqdomain into the hierarchy
@@ -1247,18 +1259,6 @@ void irq_domain_set_info(struct irq_domain *domain, unsigned int virq, }EXPORT_SYMBOL (irq_domain_set_info); -/** -* irq_domain_reset_irq_data - Clear hwirq, chip and chip_data in @irq_data -* @irq_data: The pointer to irq_data -*/ -void irq_domain_reset_irq_data (struct irq_data *irq_data) -{ - irq_data->hwirq =0 ; - irq_data->chip = &no_irq_chip; - irq_data->chip_data =NULL ; -} -EXPORT_SYMBOL_GPL (irq_domain_reset_irq_data); -/** * irq_domain_free_irqs_common - Clear irq_data and free the parent * @domain: Interrupt domain to match
Signature · 1 line
2.25.0
Re: [PATCH v4 1/2] irq: make irq_domain_reset_irq_data() available even for non-V2 users
Quoted 7 lines · Bartosz Golaszewski
From: Bartosz Golaszewski <[email protected]>
irq_domain_reset_irq_data()doesn't modify the parent data, so it can be made available even if irq domain hierarchy is not being built. We'll subsequently use it inirq_simcode.Signed-off-by Bartosz Golaszewski <[email protected]>
Makes sense to me.
Yours,
Linus Walleij
PATCH v4 2/2 irq/irq_sim: simplify the API
In reply to Bartosz GolaszewskiFrom: Bartosz Golaszewski <[email protected]>
The interrupt simulator API exposes a lot of custom data structures and functions and doesn't reuse the interfaces already exposed by the irq subsystem. This patch tries to address it.
We hide all the simulator-related data structures from users and instead rely on the well-known irq domain. When creating the interrupt simulator the user receives a pointer to a newly created irq_domain and can use it to create mappings for simulated interrupts.
It is also possible to pass a handle to fwnode when creating the simulator domain and retrieve it using irq_find_matching_fwnode().
The irq_sim_fire() function now only takes the virtual interrupt number as argument - there's no need anymore to pass it any data structure linked to the simulator.
We modify the two modules that use the simulator at the same time as adding these changes in order to reduce the intermediate bloat that would result when trying to migrate the drivers in separate patches.
--- drivers/gpio/gpio-mockup.c | 47 ++++-- drivers/iio/dummy/iio_dummy_evgen.c | 32 ++-- include/linux/irq_sim.h | 34 ++--- kernel/irq/Kconfig | 1 + kernel/irq/irq_sim.c | 225 +++++++++++++++++----------- 5 files changed, 202 insertions(+), 137 deletions(-)
drivers/gpio/gpio-mockup.c +37 -10
@@ -14,6 +14,7 @@#include <linux/interrupt.h> #include <linux/irq.h> #include <linux/irq_sim.h> +#include <linux/irqdomain.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/property.h>
@@ -48,7 +49,7 @@ struct gpio_mockup_line_status {struct gpio_mockup_chip {struct gpio_chip gc;struct gpio_mockup_line_status *lines; -struct irq_sim irqsim; +struct irq_domain *irq_sim_domain;struct dentry *dbg_dir;struct mutex lock; };
@@ -144,14 +145,12 @@ static void gpio_mockup_set_multiple(struct gpio_chip *gc,static int gpio_mockup_apply_pull (struct gpio_mockup_chip *chip,unsigned int offset,int value) { +int curr, irq, irq_type, ret =0 ;struct gpio_desc *desc;struct gpio_chip *gc; -struct irq_sim *sim; -int curr, irq, irq_type; gc = &chip->gc; desc = &gc->gpiodev->descs[offset]; - sim = &chip->irqsim;mutex_lock (&chip->lock);
@@ -161,14 +160,24 @@ static int gpio_mockup_apply_pull(struct gpio_mockup_chip *chip,if (curr == value) goto out; - irq =irq_sim_irqnum (sim, offset); + irq =irq_find_mapping (chip->irq_sim_domain, offset); +if (!irq) +/* +* This is fine - it just means, nobody is listening +* for interrupts on this line, otherwise +* irq_create_mapping() would have been called from +* the to_irq() callback. +*/ + goto set_value; + irq_type =irq_get_trigger_type (irq);if ((value ==1 && (irq_type &IRQ_TYPE_EDGE_RISING )) || (value ==0 && (irq_type &IRQ_TYPE_EDGE_FALLING ))) -irq_sim_fire (sim, offset); +irq_sim_fire (irq); } +set_value:/* Change the value unless we're actively driving the line. */ if (!test_bit (FLAG_REQUESTED , &desc->flags) || !test_bit (FLAG_IS_OUT , &desc->flags))
@@ -177,7 +186,7 @@ static int gpio_mockup_apply_pull(struct gpio_mockup_chip *chip, out: chip->lines[offset].pull = value;mutex_unlock (&chip->lock); -return 0 ; +return ret; } static int gpio_mockup_set_config(struct gpio_chip *gc,
@@ -236,7 +245,7 @@ static int gpio_mockup_to_irq(struct gpio_chip *gc, unsigned int offset) {struct gpio_mockup_chip *chip =gpiochip_get_data (gc); -return irq_sim_irqnum (&chip->irqsim, offset); +return irq_create_mapping (chip->irq_sim_domain, offset); }static void gpio_mockup_free (struct gpio_chip *gc,unsigned int offset)
@@ -389,6 +398,19 @@ static int gpio_mockup_name_lines(struct device *dev,return 0 ; } +static void gpio_mockup_dispose_mappings (void *data) +{ +struct gpio_mockup_chip *chip = data; +struct gpio_chip *gc = &chip->gc; +int i, irq; + +for (i =0 ; i < gc->ngpio; i++) { + irq =irq_find_mapping (chip->irq_sim_domain, i); +if (irq) +irq_dispose_mapping (irq); + } +} +static int gpio_mockup_probe (struct platform_device *pdev) {struct gpio_mockup_chip *chip;
@@ -456,8 +478,13 @@ static int gpio_mockup_probe(struct platform_device *pdev)return rv; } - rv =devm_irq_sim_init (dev, &chip->irqsim, gc->ngpio); -if (rv <0 ) + chip->irq_sim_domain =devm_irq_domain_create_sim (dev,NULL , + gc->ngpio); +if (IS_ERR (chip->irq_sim_domain)) +return PTR_ERR (chip->irq_sim_domain); + + rv =devm_add_action_or_reset (dev, gpio_mockup_dispose_mappings, chip); +if (rv)return rv; rv =devm_gpiochip_add_data (dev, &chip->gc, chip);
drivers/iio/dummy/iio_dummy_evgen.c +18 -14
@@ -37,8 +37,7 @@ struct iio_dummy_eventgen {struct iio_dummy_regs regs[IIO_EVENTGEN_NO ];struct mutex lock;bool inuse[IIO_EVENTGEN_NO ]; -struct irq_sim irq_sim; -int base; +struct irq_domain *irq_sim_domain; };/* We can only ever have one instance of this 'device' */
@@ -46,19 +45,17 @@ static struct iio_dummy_eventgen *iio_evgen;static int iio_dummy_evgen_create (void ) { -int ret; - iio_evgen =kzalloc (sizeof (*iio_evgen),GFP_KERNEL );if (!iio_evgen)return -ENOMEM ; - ret =irq_sim_init (&iio_evgen->irq_sim,IIO_EVENTGEN_NO ); -if (ret <0 ) { + iio_evgen->irq_sim_domain =irq_domain_create_sim (NULL , +IIO_EVENTGEN_NO ); +if (IS_ERR (iio_evgen->irq_sim_domain)) {kfree (iio_evgen); -return ret; +return PTR_ERR (iio_evgen->irq_sim_domain); } - iio_evgen->base =irq_sim_irqnum (&iio_evgen->irq_sim,0 );mutex_init (&iio_evgen->lock);return 0 ;
@@ -80,7 +77,7 @@ int iio_dummy_evgen_get_irq(void)mutex_lock (&iio_evgen->lock);for (i =0 ; i <IIO_EVENTGEN_NO ; i++) {if (!iio_evgen->inuse[i]) { - ret =irq_sim_irqnum (&iio_evgen->irq_sim, i); + ret =irq_create_mapping (iio_evgen->irq_sim_domain, i); iio_evgen->inuse[i] = true;break ; }
@@ -101,21 +98,27 @@ EXPORT_SYMBOL_GPL(iio_dummy_evgen_get_irq);*/ void iio_dummy_evgen_release_irq (int irq) { +struct irq_data *irqd =irq_get_irq_data (irq); +mutex_lock (&iio_evgen->lock); - iio_evgen->inuse[irq - iio_evgen->base] = false; + iio_evgen->inuse[irqd_to_hwirq (irqd)] = false; +irq_dispose_mapping (irq);mutex_unlock (&iio_evgen->lock); }EXPORT_SYMBOL_GPL (iio_dummy_evgen_release_irq);struct iio_dummy_regs *iio_dummy_evgen_get_regs (int irq) { -return &iio_evgen->regs[irq - iio_evgen->base]; +struct irq_data *irqd =irq_get_irq_data (irq); + +return &iio_evgen->regs[irqd_to_hwirq (irqd)]; + }EXPORT_SYMBOL_GPL (iio_dummy_evgen_get_regs);static void iio_dummy_evgen_free (void ) { -irq_sim_fini (&iio_evgen->irq_sim); +irq_domain_remove_sim (iio_evgen->irq_sim_domain);kfree (iio_evgen); }
@@ -131,7 +134,7 @@ static ssize_t iio_evgen_poke(struct device *dev, {struct iio_dev_attr *this_attr =to_iio_dev_attr (attr);unsigned long event; -int ret; +int ret, irq; ret =kstrtoul (buf,10 , &event);if (ret)
@@ -140,7 +143,8 @@ static ssize_t iio_evgen_poke(struct device *dev, iio_evgen->regs[this_attr->address].reg_id = this_attr->address; iio_evgen->regs[this_attr->address].reg_data = event; -irq_sim_fire (&iio_evgen->irq_sim, this_attr->address); + irq =irq_find_mapping (iio_evgen->irq_sim_domain, this_attr->address); +irq_sim_fire (irq);return len; }
include/linux/irq_sim.h +10 -24
@@ -1,41 +1,27 @@/* SPDX-License-Identifier: GPL-2.0+ */ /* * Copyright (C) 2017-2018 Bartosz Golaszewski <[email protected]> +* Copyright (C) 2020 Bartosz Golaszewski <[email protected]> */ #ifndef _LINUX_IRQ_SIM_H#define _LINUX_IRQ_SIM_H -#include <linux/irq_work.h> #include <linux/device.h> +#include <linux/fwnode.h> +#include <linux/irqdomain.h> /* * Provides a framework for allocating simulated interrupts which can be * requested like normal irqs and enqueued from process context. */ -struct irq_sim_work_ctx { -struct irq_work work; -unsigned long *pending; -}; - -struct irq_sim_irq_ctx { -int irqnum; -bool enabled; -}; - -struct irq_sim { -struct irq_sim_work_ctx work_ctx; -int irq_base; -unsigned int irq_count; -struct irq_sim_irq_ctx *irqs; -}; - -int irq_sim_init (struct irq_sim *sim,unsigned int num_irqs); -int devm_irq_sim_init (struct device *dev,struct irq_sim *sim, -unsigned int num_irqs); -void irq_sim_fini (struct irq_sim *sim); -void irq_sim_fire (struct irq_sim *sim,unsigned int offset); -int irq_sim_irqnum (struct irq_sim *sim,unsigned int offset); +struct irq_domain *irq_domain_create_sim (struct fwnode_handle *fwnode, +unsigned int num_irqs); +struct irq_domain *devm_irq_domain_create_sim (struct device *dev, +struct fwnode_handle *fwnode, +unsigned int num_irqs); +void irq_domain_remove_sim (struct irq_domain *domain); +void irq_sim_fire (int virq);#endif /* _LINUX_IRQ_SIM_H */
kernel/irq/Kconfig +1 -0
@@ -72,6 +72,7 @@ config IRQ_DOMAIN config IRQ_SIM bool select IRQ_WORK + select IRQ_DOMAIN # Support for hierarchical irq domains config IRQ_DOMAIN_HIERARCHY
kernel/irq/irq_sim.c +136 -89
298 lines not on this page · raw message
Signature · 1 line
2.25.0
Re: [PATCH v4 2/2] irq/irq_sim: simplify the API
Quoted 18 lines · Bartosz Golaszewski
From: Bartosz Golaszewski <[email protected]>
The interrupt simulator API exposes a lot of custom data structures and functions and doesn't reuse the interfaces already exposed by the irq subsystem. This patch tries to address it.
We hide all the simulator-related data structures from users and instead rely on the well-known irq domain. When creating the interrupt simulator the user receives a pointer to a newly created
irq_domainand can use it to create mappings for simulated interrupts.It is also possible to pass a handle to fwnode when creating the simulator domain and retrieve it using
irq_find_matching_fwnode().The
irq_sim_fire()function now only takes the virtual interrupt number as argument - there's no need anymore to pass it any data structure linked to the simulator.
Quoted 6 lines
We modify the two modules that use the simulator at the same time as adding these changes in order to reduce the intermediate bloat that would result when trying to migrate the drivers in separate patches.
Signed-off-by Bartosz Golaszewski <[email protected]>
Yours,
Linus Walleij
Re: [PATCH v4 2/2] irq/irq_sim: simplify the API
In reply to Bartosz GolaszewskiBartosz,
Quoted 31 lines · Bartosz Golaszewski
From: Bartosz Golaszewski <[email protected]>
The interrupt simulator API exposes a lot of custom data structures and functions and doesn't reuse the interfaces already exposed by the irq subsystem. This patch tries to address it.
We hide all the simulator-related data structures from users and instead rely on the well-known irq domain. When creating the interrupt simulator the user receives a pointer to a newly created
irq_domainand can use it to create mappings for simulated interrupts.It is also possible to pass a handle to fwnode when creating the simulator domain and retrieve it using
irq_find_matching_fwnode().The
irq_sim_fire()function now only takes the virtual interrupt number as argument - there's no need anymore to pass it any data structure linked to the simulator.We modify the two modules that use the simulator at the same time as adding these changes in order to reduce the intermediate bloat that would result when trying to migrate the drivers in separate patches.
Signed-off-by Bartosz Golaszewski <[email protected]>--- drivers/gpio/gpio-mockup.c | 47 ++++-- drivers/iio/dummy/iio_dummy_evgen.c | 32 ++-- include/linux/irq_sim.h | 34 ++--- kernel/irq/Kconfig | 1 + kernel/irq/irq_sim.c | 225 +++++++++++++++++----------- 5 files changed, 202 insertions(+), 137 deletions(-)
[...]
Quoted 37 lines
/**
*irq_sim_fire- Enqueue an interrupt.
*
- * @sim: The interrupt simulator object.
- * @offset: Offset of the simulated interrupt which should be
fired.
+ * @virq: Virtual interrupt number to fire. It must be
associated with
+ * an existing interrupt simulator.
*/kernel/irq/irq_sim.c +8
-11-void irq_sim_fire (struct irq_sim *sim,unsigned int offset) +void irq_sim_fire (int virq) { -if (sim->irqs[offset].enabled) { -set_bit (offset, sim->work_ctx.pending); -irq_work_queue (&sim->work_ctx.work); +struct irq_sim_irq_ctx *irq_ctx; +struct irq_data *irqd; + + irqd =irq_get_irq_data (virq); +if (!irqd) { +pr_warn_ratelimited ("%s: invalid irq number\n" , __func__); +return ; } -} -EXPORT_SYMBOL_GPL (irq_sim_fire); -/** -* irq_sim_irqnum - Get the allocated number of a dummy interrupt. -* -* @sim: The interrupt simulator object. -* @offset: Offset of the simulated interrupt for which to retrieve
- * the number.
- */kernel/irq/irq_sim.c +0
-2-int irq_sim_irqnum (struct irq_sim *sim,unsigned int offset) -{
kernel/irq/irq_sim.c static void irq_sim_handle_irq(struct irq_work *work) · line 241
Quoted 10 lines
kernel/irq/irq_sim.c +7
-2-return sim->irqs[offset].irqnum; + irq_ctx =irq_data_get_irq_chip_data (irqd); + +if (irq_ctx->enabled) { +set_bit (irqd_to_hwirq (irqd), irq_ctx->work_ctx->pending); +irq_work_queue (&irq_ctx->work_ctx->work); + } } -EXPORT_SYMBOL_GPL (irq_sim_irqnum); +EXPORT_SYMBOL_GPL (irq_sim_fire);
Rather than using an ad-hoc API to queue an interrupt, why don't you actually implement the interface that already exists for this at the irqchip level (irq_set_irqchip_state, which allows the pending state to be set)?
Thanks,
M.
Signature · 1 line
Jazz is not dead. It just smells funny...
Re: [PATCH v4 2/2] irq/irq_sim: simplify the API
wt., 12 maj 2020 o 17:37 Marc Zyngier <[email protected]> napisał(a):
Quoted 11 lines
Quoted 11 lines
- */
kernel/irq/irq_sim.c +6
-3-int irq_sim_irqnum (struct irq_sim *sim,unsigned int offset) -{ -return sim->irqs[offset].irqnum; + irq_ctx =irq_data_get_irq_chip_data (irqd); + +if (irq_ctx->enabled) { +set_bit (irqd_to_hwirq (irqd), irq_ctx->work_ctx->pending); +irq_work_queue (&irq_ctx->work_ctx->work); + }
Quoted 9 lines
kernel/irq/irq_sim.c static void irq_sim_handle_irq(struct irq_work *work) · line 241
Quoted 3 lines
}
kernel/irq/irq_sim.c +1
-1-EXPORT_SYMBOL_GPL (irq_sim_irqnum); +EXPORT_SYMBOL_GPL (irq_sim_fire);Rather than using an ad-hoc API to queue an interrupt, why don't you actually implement the interface that already exists for this at the irqchip level (
irq_set_irqchip_state, which allows the pending state to be set)?
Yes, this is great, thanks for bringing this to my attention. I can drop another function from the API.
Bart
czw., 30 kwi 2020 o 16:30 Bartosz Golaszewski <[email protected]> napisał(a):
Quoted 7 lines
From: Bartosz Golaszewski <[email protected]>
The interrupt simulator API exposes a lot of custom data structures and functions and doesn't reuse the interfaces already exposed by the irq subsystem. This series tries to address it.
Quoted 8 lines
First, we make
irq_domain_reset_irq_data()available to non-V2 domain API users - that'll be used in the subsequent patch. Next we overhaul the public interfaces - we hide all specific data structures and instead rely on theirq_domainstruct and virtual interrupt numberspace.The end effect is that we limit the interrupt simulator API to three functions (plus one device managed variant) and zero new structures.
Hi Thomas, Marc,
I've been posting this for many weeks now without any major changes and I dropped all controversial changes. Any chance of getting at least this part in for v5.8?
Bartosz