* [PATCH] irq/irq_sim: store multiple interrupt offsets in a bitmap
@ 2018-11-09 17:21 Bartosz Golaszewski
2018-12-11 14:02 ` Bartosz Golaszewski
0 siblings, 1 reply; 4+ messages in thread
From: Bartosz Golaszewski @ 2018-11-09 17:21 UTC (permalink / raw)
To: Thomas Gleixner, Uwe Kleine-König; +Cc: linux-kernel, Bartosz Golaszewski
Two threads can try to fire the irq_sim with different offsets and will
end up fighting for the irq_work asignment. Thomas Gleixner suggested a
solution based on a bitfield where we set a bit for every offset
associated with an interrupt that should be fired and then iterate over
all set bits in the interrupt handler.
This is a slightly modified solution using a bitmap so that we don't
impose a limit on the number of interrupts one can allocate with
irq_sim.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
---
include/linux/irq_sim.h | 2 +-
kernel/irq/irq_sim.c | 23 +++++++++++++++++++++--
2 files changed, 22 insertions(+), 3 deletions(-)
diff --git a/include/linux/irq_sim.h b/include/linux/irq_sim.h
index 630a57e55db6..4500d453a63e 100644
--- a/include/linux/irq_sim.h
+++ b/include/linux/irq_sim.h
@@ -16,7 +16,7 @@
struct irq_sim_work_ctx {
struct irq_work work;
- int irq;
+ unsigned long *pending;
};
struct irq_sim_irq_ctx {
diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
index dd20d0d528d4..98a20e1594ce 100644
--- a/kernel/irq/irq_sim.c
+++ b/kernel/irq/irq_sim.c
@@ -34,9 +34,20 @@ static struct irq_chip irq_sim_irqchip = {
static void irq_sim_handle_irq(struct irq_work *work)
{
struct irq_sim_work_ctx *work_ctx;
+ unsigned int offset = 0;
+ struct irq_sim *sim;
+ int irqnum;
work_ctx = container_of(work, struct irq_sim_work_ctx, work);
- handle_simple_irq(irq_to_desc(work_ctx->irq));
+ sim = container_of(work_ctx, struct irq_sim, work_ctx);
+
+ while (!bitmap_empty(work_ctx->pending, sim->irq_count)) {
+ offset = find_next_bit(work_ctx->pending,
+ sim->irq_count, offset);
+ clear_bit(offset, work_ctx->pending);
+ irqnum = irq_sim_irqnum(sim, offset);
+ handle_simple_irq(irq_to_desc(irqnum));
+ }
}
/**
@@ -63,6 +74,13 @@ int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs)
return sim->irq_base;
}
+ sim->work_ctx.pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
+ if (!sim->work_ctx.pending) {
+ kfree(sim->irqs);
+ irq_free_descs(sim->irq_base, num_irqs);
+ return -ENOMEM;
+ }
+
for (i = 0; i < num_irqs; i++) {
sim->irqs[i].irqnum = sim->irq_base + i;
sim->irqs[i].enabled = false;
@@ -89,6 +107,7 @@ EXPORT_SYMBOL_GPL(irq_sim_init);
void irq_sim_fini(struct irq_sim *sim)
{
irq_work_sync(&sim->work_ctx.work);
+ bitmap_free(sim->work_ctx.pending);
irq_free_descs(sim->irq_base, sim->irq_count);
kfree(sim->irqs);
}
@@ -143,7 +162,7 @@ EXPORT_SYMBOL_GPL(devm_irq_sim_init);
void irq_sim_fire(struct irq_sim *sim, unsigned int offset)
{
if (sim->irqs[offset].enabled) {
- sim->work_ctx.irq = irq_sim_irqnum(sim, offset);
+ set_bit(offset, sim->work_ctx.pending);
irq_work_queue(&sim->work_ctx.work);
}
}
--
2.19.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH] irq/irq_sim: store multiple interrupt offsets in a bitmap
2018-11-09 17:21 [PATCH] irq/irq_sim: store multiple interrupt offsets in a bitmap Bartosz Golaszewski
@ 2018-12-11 14:02 ` Bartosz Golaszewski
2018-12-11 14:41 ` Marc Zyngier
0 siblings, 1 reply; 4+ messages in thread
From: Bartosz Golaszewski @ 2018-12-11 14:02 UTC (permalink / raw)
To: Thomas Gleixner, Uwe Kleine-König, Marc Zyngier
Cc: Linux Kernel Mailing List
pt., 9 lis 2018 o 18:21 Bartosz Golaszewski <brgl@bgdev.pl> napisał(a):
>
> Two threads can try to fire the irq_sim with different offsets and will
> end up fighting for the irq_work asignment. Thomas Gleixner suggested a
> solution based on a bitfield where we set a bit for every offset
> associated with an interrupt that should be fired and then iterate over
> all set bits in the interrupt handler.
>
> This is a slightly modified solution using a bitmap so that we don't
> impose a limit on the number of interrupts one can allocate with
> irq_sim.
>
> Suggested-by: Thomas Gleixner <tglx@linutronix.de>
> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
> ---
> include/linux/irq_sim.h | 2 +-
> kernel/irq/irq_sim.c | 23 +++++++++++++++++++++--
> 2 files changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/include/linux/irq_sim.h b/include/linux/irq_sim.h
> index 630a57e55db6..4500d453a63e 100644
> --- a/include/linux/irq_sim.h
> +++ b/include/linux/irq_sim.h
> @@ -16,7 +16,7 @@
>
> struct irq_sim_work_ctx {
> struct irq_work work;
> - int irq;
> + unsigned long *pending;
> };
>
> struct irq_sim_irq_ctx {
> diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
> index dd20d0d528d4..98a20e1594ce 100644
> --- a/kernel/irq/irq_sim.c
> +++ b/kernel/irq/irq_sim.c
> @@ -34,9 +34,20 @@ static struct irq_chip irq_sim_irqchip = {
> static void irq_sim_handle_irq(struct irq_work *work)
> {
> struct irq_sim_work_ctx *work_ctx;
> + unsigned int offset = 0;
> + struct irq_sim *sim;
> + int irqnum;
>
> work_ctx = container_of(work, struct irq_sim_work_ctx, work);
> - handle_simple_irq(irq_to_desc(work_ctx->irq));
> + sim = container_of(work_ctx, struct irq_sim, work_ctx);
> +
> + while (!bitmap_empty(work_ctx->pending, sim->irq_count)) {
> + offset = find_next_bit(work_ctx->pending,
> + sim->irq_count, offset);
> + clear_bit(offset, work_ctx->pending);
> + irqnum = irq_sim_irqnum(sim, offset);
> + handle_simple_irq(irq_to_desc(irqnum));
> + }
> }
>
> /**
> @@ -63,6 +74,13 @@ int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs)
> return sim->irq_base;
> }
>
> + sim->work_ctx.pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
> + if (!sim->work_ctx.pending) {
> + kfree(sim->irqs);
> + irq_free_descs(sim->irq_base, num_irqs);
> + return -ENOMEM;
> + }
> +
> for (i = 0; i < num_irqs; i++) {
> sim->irqs[i].irqnum = sim->irq_base + i;
> sim->irqs[i].enabled = false;
> @@ -89,6 +107,7 @@ EXPORT_SYMBOL_GPL(irq_sim_init);
> void irq_sim_fini(struct irq_sim *sim)
> {
> irq_work_sync(&sim->work_ctx.work);
> + bitmap_free(sim->work_ctx.pending);
> irq_free_descs(sim->irq_base, sim->irq_count);
> kfree(sim->irqs);
> }
> @@ -143,7 +162,7 @@ EXPORT_SYMBOL_GPL(devm_irq_sim_init);
> void irq_sim_fire(struct irq_sim *sim, unsigned int offset)
> {
> if (sim->irqs[offset].enabled) {
> - sim->work_ctx.irq = irq_sim_irqnum(sim, offset);
> + set_bit(offset, sim->work_ctx.pending);
> irq_work_queue(&sim->work_ctx.work);
> }
> }
> --
> 2.19.1
>
Ping and Cc'ing Marc Zyngier. Any chance of getting this in for 4.21?
Bart
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] irq/irq_sim: store multiple interrupt offsets in a bitmap
2018-12-11 14:02 ` Bartosz Golaszewski
@ 2018-12-11 14:41 ` Marc Zyngier
2018-12-11 15:39 ` Bartosz Golaszewski
0 siblings, 1 reply; 4+ messages in thread
From: Marc Zyngier @ 2018-12-11 14:41 UTC (permalink / raw)
To: Bartosz Golaszewski, Thomas Gleixner, Uwe Kleine-König
Cc: Linux Kernel Mailing List
On 11/12/2018 14:02, Bartosz Golaszewski wrote:
> pt., 9 lis 2018 o 18:21 Bartosz Golaszewski <brgl@bgdev.pl> napisał(a):
>>
>> Two threads can try to fire the irq_sim with different offsets and will
>> end up fighting for the irq_work asignment. Thomas Gleixner suggested a
>> solution based on a bitfield where we set a bit for every offset
>> associated with an interrupt that should be fired and then iterate over
>> all set bits in the interrupt handler.
>>
>> This is a slightly modified solution using a bitmap so that we don't
>> impose a limit on the number of interrupts one can allocate with
>> irq_sim.
>>
>> Suggested-by: Thomas Gleixner <tglx@linutronix.de>
>> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
>> ---
>> include/linux/irq_sim.h | 2 +-
>> kernel/irq/irq_sim.c | 23 +++++++++++++++++++++--
>> 2 files changed, 22 insertions(+), 3 deletions(-)
>>
>> diff --git a/include/linux/irq_sim.h b/include/linux/irq_sim.h
>> index 630a57e55db6..4500d453a63e 100644
>> --- a/include/linux/irq_sim.h
>> +++ b/include/linux/irq_sim.h
>> @@ -16,7 +16,7 @@
>>
>> struct irq_sim_work_ctx {
>> struct irq_work work;
>> - int irq;
>> + unsigned long *pending;
>> };
>>
>> struct irq_sim_irq_ctx {
>> diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
>> index dd20d0d528d4..98a20e1594ce 100644
>> --- a/kernel/irq/irq_sim.c
>> +++ b/kernel/irq/irq_sim.c
>> @@ -34,9 +34,20 @@ static struct irq_chip irq_sim_irqchip = {
>> static void irq_sim_handle_irq(struct irq_work *work)
>> {
>> struct irq_sim_work_ctx *work_ctx;
>> + unsigned int offset = 0;
>> + struct irq_sim *sim;
>> + int irqnum;
>>
>> work_ctx = container_of(work, struct irq_sim_work_ctx, work);
>> - handle_simple_irq(irq_to_desc(work_ctx->irq));
>> + sim = container_of(work_ctx, struct irq_sim, work_ctx);
>> +
>> + while (!bitmap_empty(work_ctx->pending, sim->irq_count)) {
>> + offset = find_next_bit(work_ctx->pending,
>> + sim->irq_count, offset);
>> + clear_bit(offset, work_ctx->pending);
>> + irqnum = irq_sim_irqnum(sim, offset);
>> + handle_simple_irq(irq_to_desc(irqnum));
>> + }
>> }
>>
>> /**
>> @@ -63,6 +74,13 @@ int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs)
>> return sim->irq_base;
>> }
>>
>> + sim->work_ctx.pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
>> + if (!sim->work_ctx.pending) {
>> + kfree(sim->irqs);
>> + irq_free_descs(sim->irq_base, num_irqs);
>> + return -ENOMEM;
>> + }
>> +
>> for (i = 0; i < num_irqs; i++) {
>> sim->irqs[i].irqnum = sim->irq_base + i;
>> sim->irqs[i].enabled = false;
>> @@ -89,6 +107,7 @@ EXPORT_SYMBOL_GPL(irq_sim_init);
>> void irq_sim_fini(struct irq_sim *sim)
>> {
>> irq_work_sync(&sim->work_ctx.work);
>> + bitmap_free(sim->work_ctx.pending);
>> irq_free_descs(sim->irq_base, sim->irq_count);
>> kfree(sim->irqs);
>> }
>> @@ -143,7 +162,7 @@ EXPORT_SYMBOL_GPL(devm_irq_sim_init);
>> void irq_sim_fire(struct irq_sim *sim, unsigned int offset)
>> {
>> if (sim->irqs[offset].enabled) {
>> - sim->work_ctx.irq = irq_sim_irqnum(sim, offset);
>> + set_bit(offset, sim->work_ctx.pending);
>> irq_work_queue(&sim->work_ctx.work);
>> }
>> }
>> --
>> 2.19.1
>>
>
> Ping and Cc'ing Marc Zyngier. Any chance of getting this in for 4.21?
Bizarrely, I can't find any trace of this patch in my Inbox. I've now
cherry-picked from https://lore.kernel.org/patchwork/patch/1009297/ .
Thanks,
M.
--
Jazz is not dead. It just smells funny...
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] irq/irq_sim: store multiple interrupt offsets in a bitmap
2018-12-11 14:41 ` Marc Zyngier
@ 2018-12-11 15:39 ` Bartosz Golaszewski
0 siblings, 0 replies; 4+ messages in thread
From: Bartosz Golaszewski @ 2018-12-11 15:39 UTC (permalink / raw)
To: Marc Zyngier
Cc: Thomas Gleixner, Uwe Kleine-König, Linux Kernel Mailing List
wt., 11 gru 2018 o 15:42 Marc Zyngier <marc.zyngier@arm.com> napisał(a):
>
> On 11/12/2018 14:02, Bartosz Golaszewski wrote:
> > pt., 9 lis 2018 o 18:21 Bartosz Golaszewski <brgl@bgdev.pl> napisał(a):
> >>
> >> Two threads can try to fire the irq_sim with different offsets and will
> >> end up fighting for the irq_work asignment. Thomas Gleixner suggested a
> >> solution based on a bitfield where we set a bit for every offset
> >> associated with an interrupt that should be fired and then iterate over
> >> all set bits in the interrupt handler.
> >>
> >> This is a slightly modified solution using a bitmap so that we don't
> >> impose a limit on the number of interrupts one can allocate with
> >> irq_sim.
> >>
> >> Suggested-by: Thomas Gleixner <tglx@linutronix.de>
> >> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
> >> ---
> >> include/linux/irq_sim.h | 2 +-
> >> kernel/irq/irq_sim.c | 23 +++++++++++++++++++++--
> >> 2 files changed, 22 insertions(+), 3 deletions(-)
> >>
> >> diff --git a/include/linux/irq_sim.h b/include/linux/irq_sim.h
> >> index 630a57e55db6..4500d453a63e 100644
> >> --- a/include/linux/irq_sim.h
> >> +++ b/include/linux/irq_sim.h
> >> @@ -16,7 +16,7 @@
> >>
> >> struct irq_sim_work_ctx {
> >> struct irq_work work;
> >> - int irq;
> >> + unsigned long *pending;
> >> };
> >>
> >> struct irq_sim_irq_ctx {
> >> diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
> >> index dd20d0d528d4..98a20e1594ce 100644
> >> --- a/kernel/irq/irq_sim.c
> >> +++ b/kernel/irq/irq_sim.c
> >> @@ -34,9 +34,20 @@ static struct irq_chip irq_sim_irqchip = {
> >> static void irq_sim_handle_irq(struct irq_work *work)
> >> {
> >> struct irq_sim_work_ctx *work_ctx;
> >> + unsigned int offset = 0;
> >> + struct irq_sim *sim;
> >> + int irqnum;
> >>
> >> work_ctx = container_of(work, struct irq_sim_work_ctx, work);
> >> - handle_simple_irq(irq_to_desc(work_ctx->irq));
> >> + sim = container_of(work_ctx, struct irq_sim, work_ctx);
> >> +
> >> + while (!bitmap_empty(work_ctx->pending, sim->irq_count)) {
> >> + offset = find_next_bit(work_ctx->pending,
> >> + sim->irq_count, offset);
> >> + clear_bit(offset, work_ctx->pending);
> >> + irqnum = irq_sim_irqnum(sim, offset);
> >> + handle_simple_irq(irq_to_desc(irqnum));
> >> + }
> >> }
> >>
> >> /**
> >> @@ -63,6 +74,13 @@ int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs)
> >> return sim->irq_base;
> >> }
> >>
> >> + sim->work_ctx.pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
> >> + if (!sim->work_ctx.pending) {
> >> + kfree(sim->irqs);
> >> + irq_free_descs(sim->irq_base, num_irqs);
> >> + return -ENOMEM;
> >> + }
> >> +
> >> for (i = 0; i < num_irqs; i++) {
> >> sim->irqs[i].irqnum = sim->irq_base + i;
> >> sim->irqs[i].enabled = false;
> >> @@ -89,6 +107,7 @@ EXPORT_SYMBOL_GPL(irq_sim_init);
> >> void irq_sim_fini(struct irq_sim *sim)
> >> {
> >> irq_work_sync(&sim->work_ctx.work);
> >> + bitmap_free(sim->work_ctx.pending);
> >> irq_free_descs(sim->irq_base, sim->irq_count);
> >> kfree(sim->irqs);
> >> }
> >> @@ -143,7 +162,7 @@ EXPORT_SYMBOL_GPL(devm_irq_sim_init);
> >> void irq_sim_fire(struct irq_sim *sim, unsigned int offset)
> >> {
> >> if (sim->irqs[offset].enabled) {
> >> - sim->work_ctx.irq = irq_sim_irqnum(sim, offset);
> >> + set_bit(offset, sim->work_ctx.pending);
> >> irq_work_queue(&sim->work_ctx.work);
> >> }
> >> }
> >> --
> >> 2.19.1
> >>
> >
> > Ping and Cc'ing Marc Zyngier. Any chance of getting this in for 4.21?
>
> Bizarrely, I can't find any trace of this patch in my Inbox. I've now
> cherry-picked from https://lore.kernel.org/patchwork/patch/1009297/ .
>
Your e-mail doesn't pop up with get_maintainer on this patch. That's
why you didn't get it initially.
Bart
^ permalink raw reply [flat|nested] 4+ messages in thread
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2018-11-09 17:21 [PATCH] irq/irq_sim: store multiple interrupt offsets in a bitmap Bartosz Golaszewski
2018-12-11 14:02 ` Bartosz Golaszewski
2018-12-11 14:41 ` Marc Zyngier
2018-12-11 15:39 ` Bartosz Golaszewski
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