Messages in this thread | | | From | Bartosz Golaszewski <> | Date | Tue, 11 Dec 2018 16:39:48 +0100 | Subject | Re: [PATCH] irq/irq_sim: store multiple interrupt offsets in a bitmap |
| |
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
| |