From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [PATCH v2 2/9] irq/irq_sim: use irq domain Date: Mon, 11 Feb 2019 22:26:14 +0000 Message-ID: <20190211222610.42e9189b@why.wild-wind.fr.eu.org> References: <20190129084411.30495-1-brgl@bgdev.pl> <20190129084411.30495-3-brgl@bgdev.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190129084411.30495-3-brgl@bgdev.pl> Sender: linux-kernel-owner@vger.kernel.org To: Bartosz Golaszewski Cc: Linus Walleij , Thomas Gleixner , Uwe =?UTF-8?B?S2xlaW5lLUvDtm5pZw==?= , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski List-Id: linux-gpio@vger.kernel.org On Tue, 29 Jan 2019 09:44:04 +0100 Bartosz Golaszewski wrote: > From: Bartosz Golaszewski > > Delegate the offset to virq number mapping to the provided framework > instead of handling it locally. Use the legacy domain as we want to > preallocate the irq descriptors. Why? > > Signed-off-by: Bartosz Golaszewski > --- > include/linux/irq_sim.h | 6 +-- > kernel/irq/irq_sim.c | 94 +++++++++++++++++++++++++++++------------ > 2 files changed, 71 insertions(+), 29 deletions(-) > > diff --git a/include/linux/irq_sim.h b/include/linux/irq_sim.h > index eda132c22b57..b96c2f752320 100644 > --- a/include/linux/irq_sim.h > +++ b/include/linux/irq_sim.h > @@ -8,6 +8,7 @@ > > #include > #include > +#include > #include > > /* > @@ -21,16 +22,15 @@ struct irq_sim_work_ctx { > }; > > struct irq_sim_irq_ctx { > - int irqnum; > bool enabled; > }; > > struct irq_sim { > struct irq_chip chip; > + struct irq_domain *domain; > struct irq_sim_work_ctx work_ctx; > - int irq_base; > + int virq_base; > unsigned int irq_count; > - struct irq_sim_irq_ctx *irqs; > }; > > int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs); > diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c > index b732e4e2e45b..2bcdbab1bc5a 100644 > --- a/kernel/irq/irq_sim.c > +++ b/kernel/irq/irq_sim.c > @@ -44,6 +44,43 @@ static void irq_sim_handle_irq(struct irq_work *work) > } > } > > +static int irq_sim_domain_map(struct irq_domain *domain, > + unsigned int virq, irq_hw_number_t hw) > +{ > + struct irq_sim *sim = domain->host_data; > + struct irq_sim_irq_ctx *ctx; > + > + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); > + if (!ctx) > + return -ENOMEM; > + > + irq_set_chip(virq, &sim->chip); > + irq_set_chip_data(virq, ctx); > + irq_set_handler(virq, handle_simple_irq); Consider using modern APIs such as irq_domain_set_info(). > + irq_modify_status(virq, IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE); Where is this requirement coming from? > + > + return 0; > +} > + > +static void irq_sim_domain_free(struct irq_domain *domain, > + unsigned int virq, unsigned int num_irqs) > +{ > + struct irq_sim_irq_ctx *ctx; > + struct irq_data *irq; > + int i; > + > + for (i = 0; i < num_irqs; i++) { > + irq = irq_domain_get_irq_data(domain, virq + i); > + ctx = irq_data_get_irq_chip_data(irq); > + kfree(ctx); > + } > +} > + > +static const struct irq_domain_ops irq_sim_domain_ops = { > + .map = irq_sim_domain_map, > + .free = irq_sim_domain_free, The intended use of the v2 API is to have alloc and free as a pair, and no map. So please choose which version of the API you're using here. The safest bet would be to move what you do on map into alloc. > +}; > + > /** > * irq_sim_init - Initialize the interrupt simulator: allocate a range of > * dummy interrupts. > @@ -56,16 +93,15 @@ static void irq_sim_handle_irq(struct irq_work *work) > */ > int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs) > { > - int i; > - > - sim->irqs = kmalloc_array(num_irqs, sizeof(*sim->irqs), GFP_KERNEL); > - if (!sim->irqs) > + sim->virq_base = irq_alloc_descs(-1, 0, num_irqs, 0); > + if (sim->virq_base < 0) > + return sim->virq_base; > + > + sim->domain = irq_domain_add_legacy(NULL, num_irqs, sim->virq_base, > + 0, &irq_sim_domain_ops, sim); Why do you need a legacy domain? As far as I can tell, this is new code, hence it has no legacy. > + if (!sim->domain) { > + irq_free_descs(sim->virq_base, num_irqs); > return -ENOMEM; > - > - sim->irq_base = irq_alloc_descs(-1, 0, num_irqs, 0); > - if (sim->irq_base < 0) { > - kfree(sim->irqs); > - return sim->irq_base; > } > > sim->chip.name = "irq_sim"; > @@ -74,25 +110,15 @@ int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs) > > 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); > + irq_domain_remove(sim->domain); > + irq_free_descs(sim->virq_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; > - irq_set_chip(sim->irq_base + i, &sim->chip); > - irq_set_chip_data(sim->irq_base + i, &sim->irqs[i]); > - irq_set_handler(sim->irq_base + i, &handle_simple_irq); > - irq_modify_status(sim->irq_base + i, > - IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE); > - } > - > init_irq_work(&sim->work_ctx.work, irq_sim_handle_irq); > sim->irq_count = num_irqs; > > - return sim->irq_base; > + return sim->virq_base; > } > EXPORT_SYMBOL_GPL(irq_sim_init); > > @@ -106,8 +132,8 @@ 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); > + irq_domain_free_irqs(sim->virq_base, sim->irq_count); > + irq_domain_remove(sim->domain); > } > EXPORT_SYMBOL_GPL(irq_sim_fini); > > @@ -151,6 +177,20 @@ int devm_irq_sim_init(struct device *dev, struct irq_sim *sim, > } > EXPORT_SYMBOL_GPL(devm_irq_sim_init); > > +static struct irq_sim_irq_ctx * > +irq_sim_get_ctx(struct irq_sim *sim, unsigned int offset) > +{ > + struct irq_sim_irq_ctx *ctx; > + struct irq_data *irq; > + int virq; > + > + virq = irq_find_mapping(sim->domain, offset); > + irq = irq_domain_get_irq_data(sim->domain, virq); > + ctx = irq_data_get_irq_chip_data(irq); > + > + return ctx; > +} > + > /** > * irq_sim_fire - Enqueue an interrupt. > * > @@ -159,7 +199,9 @@ EXPORT_SYMBOL_GPL(devm_irq_sim_init); > */ > void irq_sim_fire(struct irq_sim *sim, unsigned int offset) > { > - if (sim->irqs[offset].enabled) { > + struct irq_sim_irq_ctx *ctx = irq_sim_get_ctx(sim, offset); > + > + if (ctx->enabled) { > set_bit(offset, sim->work_ctx.pending); > irq_work_queue(&sim->work_ctx.work); > } > @@ -175,6 +217,6 @@ EXPORT_SYMBOL_GPL(irq_sim_fire); > */ > int irq_sim_irqnum(struct irq_sim *sim, unsigned int offset) > { > - return sim->irqs[offset].irqnum; > + return irq_find_mapping(sim->domain, offset); > } > EXPORT_SYMBOL_GPL(irq_sim_irqnum); Thanks, M. -- Without deviation from the norm, progress is not possible.