From 8190cc572981f2f13b6ffc26c7cfa7899e5d3ccc Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Fri, 1 Jul 2022 15:00:49 -0500 Subject: irqchip/mips-gic: Only register IPI domain when SMP is enabled The MIPS GIC irqchip driver may be selected in a uniprocessor configuration, but it unconditionally registers an IPI domain. Limit the part of the driver dealing with IPIs to only be compiled when GENERIC_IRQ_IPI is enabled, which corresponds to an SMP configuration. Reported-by: kernel test robot Signed-off-by: Samuel Holland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220701200056.46555-2-samuel@sholland.org --- drivers/irqchip/Kconfig | 3 +- drivers/irqchip/irq-mips-gic.c | 80 ++++++++++++++++++++++++++++-------------- 2 files changed, 56 insertions(+), 27 deletions(-) (limited to 'drivers/irqchip') diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index 1f23a6be7d88..d26a4ff7c99f 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -322,7 +322,8 @@ config KEYSTONE_IRQ config MIPS_GIC bool - select GENERIC_IRQ_IPI + select GENERIC_IRQ_IPI if SMP + select IRQ_DOMAIN_HIERARCHY select MIPS_CM config INGENIC_IRQ diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c index ff89b36267dd..8a9efb6ae587 100644 --- a/drivers/irqchip/irq-mips-gic.c +++ b/drivers/irqchip/irq-mips-gic.c @@ -52,13 +52,15 @@ static DEFINE_PER_CPU_READ_MOSTLY(unsigned long[GIC_MAX_LONGS], pcpu_masks); static DEFINE_SPINLOCK(gic_lock); static struct irq_domain *gic_irq_domain; -static struct irq_domain *gic_ipi_domain; static int gic_shared_intrs; static unsigned int gic_cpu_pin; static unsigned int timer_cpu_pin; static struct irq_chip gic_level_irq_controller, gic_edge_irq_controller; + +#ifdef CONFIG_GENERIC_IRQ_IPI static DECLARE_BITMAP(ipi_resrv, GIC_MAX_INTRS); static DECLARE_BITMAP(ipi_available, GIC_MAX_INTRS); +#endif /* CONFIG_GENERIC_IRQ_IPI */ static struct gic_all_vpes_chip_data { u32 map; @@ -472,9 +474,11 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq, u32 map; if (hwirq >= GIC_SHARED_HWIRQ_BASE) { +#ifdef CONFIG_GENERIC_IRQ_IPI /* verify that shared irqs don't conflict with an IPI irq */ if (test_bit(GIC_HWIRQ_TO_SHARED(hwirq), ipi_resrv)) return -EBUSY; +#endif /* CONFIG_GENERIC_IRQ_IPI */ err = irq_domain_set_hwirq_and_chip(d, virq, hwirq, &gic_level_irq_controller, @@ -567,6 +571,8 @@ static const struct irq_domain_ops gic_irq_domain_ops = { .map = gic_irq_domain_map, }; +#ifdef CONFIG_GENERIC_IRQ_IPI + static int gic_ipi_domain_xlate(struct irq_domain *d, struct device_node *ctrlr, const u32 *intspec, unsigned int intsize, irq_hw_number_t *out_hwirq, @@ -670,6 +676,48 @@ static const struct irq_domain_ops gic_ipi_domain_ops = { .match = gic_ipi_domain_match, }; +static int gic_register_ipi_domain(struct device_node *node) +{ + struct irq_domain *gic_ipi_domain; + unsigned int v[2], num_ipis; + + gic_ipi_domain = irq_domain_add_hierarchy(gic_irq_domain, + IRQ_DOMAIN_FLAG_IPI_PER_CPU, + GIC_NUM_LOCAL_INTRS + gic_shared_intrs, + node, &gic_ipi_domain_ops, NULL); + if (!gic_ipi_domain) { + pr_err("Failed to add IPI domain"); + return -ENXIO; + } + + irq_domain_update_bus_token(gic_ipi_domain, DOMAIN_BUS_IPI); + + if (node && + !of_property_read_u32_array(node, "mti,reserved-ipi-vectors", v, 2)) { + bitmap_set(ipi_resrv, v[0], v[1]); + } else { + /* + * Reserve 2 interrupts per possible CPU/VP for use as IPIs, + * meeting the requirements of arch/mips SMP. + */ + num_ipis = 2 * num_possible_cpus(); + bitmap_set(ipi_resrv, gic_shared_intrs - num_ipis, num_ipis); + } + + bitmap_copy(ipi_available, ipi_resrv, GIC_MAX_INTRS); + + return 0; +} + +#else /* !CONFIG_GENERIC_IRQ_IPI */ + +static inline int gic_register_ipi_domain(struct device_node *node) +{ + return 0; +} + +#endif /* !CONFIG_GENERIC_IRQ_IPI */ + static int gic_cpu_startup(unsigned int cpu) { /* Enable or disable EIC */ @@ -688,11 +736,12 @@ static int gic_cpu_startup(unsigned int cpu) static int __init gic_of_init(struct device_node *node, struct device_node *parent) { - unsigned int cpu_vec, i, gicconfig, v[2], num_ipis; + unsigned int cpu_vec, i, gicconfig; unsigned long reserved; phys_addr_t gic_base; struct resource res; size_t gic_len; + int ret; /* Find the first available CPU vector. */ i = 0; @@ -780,30 +829,9 @@ static int __init gic_of_init(struct device_node *node, return -ENXIO; } - gic_ipi_domain = irq_domain_add_hierarchy(gic_irq_domain, - IRQ_DOMAIN_FLAG_IPI_PER_CPU, - GIC_NUM_LOCAL_INTRS + gic_shared_intrs, - node, &gic_ipi_domain_ops, NULL); - if (!gic_ipi_domain) { - pr_err("Failed to add IPI domain"); - return -ENXIO; - } - - irq_domain_update_bus_token(gic_ipi_domain, DOMAIN_BUS_IPI); - - if (node && - !of_property_read_u32_array(node, "mti,reserved-ipi-vectors", v, 2)) { - bitmap_set(ipi_resrv, v[0], v[1]); - } else { - /* - * Reserve 2 interrupts per possible CPU/VP for use as IPIs, - * meeting the requirements of arch/mips SMP. - */ - num_ipis = 2 * num_possible_cpus(); - bitmap_set(ipi_resrv, gic_shared_intrs - num_ipis, num_ipis); - } - - bitmap_copy(ipi_available, ipi_resrv, GIC_MAX_INTRS); + ret = gic_register_ipi_domain(node); + if (ret) + return ret; board_bind_eic_interrupt = &gic_bind_eic_interrupt; -- cgit v1.2.3-58-ga151 From 0f5209fee90b4544c58b4278d944425292789967 Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Fri, 1 Jul 2022 15:00:50 -0500 Subject: genirq: GENERIC_IRQ_IPI depends on SMP The generic IPI code depends on the IRQ affinity mask being allocated and initialized. This will not be the case if SMP is disabled. Fix up the remaining driver that selected GENERIC_IRQ_IPI in a non-SMP config. Reported-by: kernel test robot Signed-off-by: Samuel Holland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220701200056.46555-3-samuel@sholland.org --- drivers/irqchip/Kconfig | 2 +- kernel/irq/Kconfig | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/irqchip') diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index d26a4ff7c99f..5dd98a81efc8 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -177,7 +177,7 @@ config MADERA_IRQ config IRQ_MIPS_CPU bool select GENERIC_IRQ_CHIP - select GENERIC_IRQ_IPI if SYS_SUPPORTS_MULTITHREADING + select GENERIC_IRQ_IPI if SMP && SYS_SUPPORTS_MULTITHREADING select IRQ_DOMAIN select GENERIC_IRQ_EFFECTIVE_AFF_MASK diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 10929eda9825..fc760d064a65 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -82,6 +82,7 @@ config IRQ_FASTEOI_HIERARCHY_HANDLERS # Generic IRQ IPI support config GENERIC_IRQ_IPI bool + depends on SMP select IRQ_DOMAIN_HIERARCHY # Generic MSI interrupt support -- cgit v1.2.3-58-ga151 From 0e6c027c035507abc67b356264a12c49f58c946e Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Fri, 1 Jul 2022 15:00:51 -0500 Subject: genirq: GENERIC_IRQ_EFFECTIVE_AFF_MASK depends on SMP An IRQ's effective affinity can only be different from its configured affinity if there are multiple CPUs. Make it clear that this option is only meaningful when SMP is enabled. Most of the relevant code in irqdesc.c is already hidden behind CONFIG_SMP anyway. Signed-off-by: Samuel Holland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220701200056.46555-4-samuel@sholland.org --- arch/arm/mach-hisi/Kconfig | 2 +- drivers/irqchip/Kconfig | 14 +++++++------- kernel/irq/Kconfig | 1 + 3 files changed, 9 insertions(+), 8 deletions(-) (limited to 'drivers/irqchip') diff --git a/arch/arm/mach-hisi/Kconfig b/arch/arm/mach-hisi/Kconfig index 75cccbd3f05f..7b3440687176 100644 --- a/arch/arm/mach-hisi/Kconfig +++ b/arch/arm/mach-hisi/Kconfig @@ -40,7 +40,7 @@ config ARCH_HIP04 select HAVE_ARM_ARCH_TIMER select MCPM if SMP select MCPM_QUAD_CLUSTER if SMP - select GENERIC_IRQ_EFFECTIVE_AFF_MASK + select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP help Support for Hisilicon HiP04 SoC family diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index 5dd98a81efc8..462adac905a6 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -8,7 +8,7 @@ config IRQCHIP config ARM_GIC bool select IRQ_DOMAIN_HIERARCHY - select GENERIC_IRQ_EFFECTIVE_AFF_MASK + select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP config ARM_GIC_PM bool @@ -34,7 +34,7 @@ config ARM_GIC_V3 bool select IRQ_DOMAIN_HIERARCHY select PARTITION_PERCPU - select GENERIC_IRQ_EFFECTIVE_AFF_MASK + select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP config ARM_GIC_V3_ITS bool @@ -76,7 +76,7 @@ config ARMADA_370_XP_IRQ bool select GENERIC_IRQ_CHIP select PCI_MSI if PCI - select GENERIC_IRQ_EFFECTIVE_AFF_MASK + select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP config ALPINE_MSI bool @@ -112,7 +112,7 @@ config BCM6345_L1_IRQ bool select GENERIC_IRQ_CHIP select IRQ_DOMAIN - select GENERIC_IRQ_EFFECTIVE_AFF_MASK + select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP config BCM7038_L1_IRQ tristate "Broadcom STB 7038-style L1/L2 interrupt controller driver" @@ -120,7 +120,7 @@ config BCM7038_L1_IRQ default ARCH_BRCMSTB || BMIPS_GENERIC select GENERIC_IRQ_CHIP select IRQ_DOMAIN - select GENERIC_IRQ_EFFECTIVE_AFF_MASK + select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP config BCM7120_L2_IRQ tristate "Broadcom STB 7120-style L2 interrupt controller driver" @@ -179,7 +179,7 @@ config IRQ_MIPS_CPU select GENERIC_IRQ_CHIP select GENERIC_IRQ_IPI if SMP && SYS_SUPPORTS_MULTITHREADING select IRQ_DOMAIN - select GENERIC_IRQ_EFFECTIVE_AFF_MASK + select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP config CLPS711X_IRQCHIP bool @@ -294,7 +294,7 @@ config VERSATILE_FPGA_IRQ_NR config XTENSA_MX bool select IRQ_DOMAIN - select GENERIC_IRQ_EFFECTIVE_AFF_MASK + select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP config XILINX_INTC bool "Xilinx Interrupt Controller IP" diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index fc760d064a65..db3d174c53d4 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -24,6 +24,7 @@ config GENERIC_IRQ_SHOW_LEVEL # Supports effective affinity mask config GENERIC_IRQ_EFFECTIVE_AFF_MASK + depends on SMP bool # Support for delayed migration from interrupt context -- cgit v1.2.3-58-ga151 From 073352e951f60946452da358d64841066c3142ff Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Fri, 1 Jul 2022 15:00:54 -0500 Subject: genirq: Add and use an irq_data_update_affinity helper Some architectures and irqchip drivers modify the cpumask returned by irq_data_get_affinity_mask, usually by copying in to it. This is problematic for uniprocessor configurations, where the affinity mask should be constant, as it is known at compile time. Add and use a setter for the affinity mask, following the pattern of irq_data_update_effective_affinity. This allows the getter function to return a const cpumask pointer. Signed-off-by: Samuel Holland Reviewed-by: Oleksandr Tyshchenko # Xen bits Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220701200056.46555-7-samuel@sholland.org --- arch/alpha/kernel/irq.c | 2 +- arch/ia64/kernel/iosapic.c | 2 +- arch/ia64/kernel/irq.c | 4 ++-- arch/ia64/kernel/msi_ia64.c | 4 ++-- arch/parisc/kernel/irq.c | 2 +- drivers/irqchip/irq-bcm6345-l1.c | 4 ++-- drivers/parisc/iosapic.c | 2 +- drivers/sh/intc/chip.c | 2 +- drivers/xen/events/events_base.c | 7 ++++--- include/linux/irq.h | 6 ++++++ 10 files changed, 21 insertions(+), 14 deletions(-) (limited to 'drivers/irqchip') diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c index f6d2946edbd2..15f2effd6baf 100644 --- a/arch/alpha/kernel/irq.c +++ b/arch/alpha/kernel/irq.c @@ -60,7 +60,7 @@ int irq_select_affinity(unsigned int irq) cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0); last_cpu = cpu; - cpumask_copy(irq_data_get_affinity_mask(data), cpumask_of(cpu)); + irq_data_update_affinity(data, cpumask_of(cpu)); chip->irq_set_affinity(data, cpumask_of(cpu), false); return 0; } diff --git a/arch/ia64/kernel/iosapic.c b/arch/ia64/kernel/iosapic.c index 35adcf89035a..99300850abc1 100644 --- a/arch/ia64/kernel/iosapic.c +++ b/arch/ia64/kernel/iosapic.c @@ -834,7 +834,7 @@ iosapic_unregister_intr (unsigned int gsi) if (iosapic_intr_info[irq].count == 0) { #ifdef CONFIG_SMP /* Clear affinity */ - cpumask_setall(irq_get_affinity_mask(irq)); + irq_data_update_affinity(irq_get_irq_data(irq), cpu_all_mask); #endif /* Clear the interrupt information */ iosapic_intr_info[irq].dest = 0; diff --git a/arch/ia64/kernel/irq.c b/arch/ia64/kernel/irq.c index ecef17c7c35b..275b9ea58c64 100644 --- a/arch/ia64/kernel/irq.c +++ b/arch/ia64/kernel/irq.c @@ -57,8 +57,8 @@ static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 }; void set_irq_affinity_info (unsigned int irq, int hwid, int redir) { if (irq < NR_IRQS) { - cpumask_copy(irq_get_affinity_mask(irq), - cpumask_of(cpu_logical_id(hwid))); + irq_data_update_affinity(irq_get_irq_data(irq), + cpumask_of(cpu_logical_id(hwid))); irq_redir[irq] = (char) (redir & 0xff); } } diff --git a/arch/ia64/kernel/msi_ia64.c b/arch/ia64/kernel/msi_ia64.c index df5c28f252e3..025e5133c860 100644 --- a/arch/ia64/kernel/msi_ia64.c +++ b/arch/ia64/kernel/msi_ia64.c @@ -37,7 +37,7 @@ static int ia64_set_msi_irq_affinity(struct irq_data *idata, msg.data = data; pci_write_msi_msg(irq, &msg); - cpumask_copy(irq_data_get_affinity_mask(idata), cpumask_of(cpu)); + irq_data_update_affinity(idata, cpumask_of(cpu)); return 0; } @@ -132,7 +132,7 @@ static int dmar_msi_set_affinity(struct irq_data *data, msg.address_lo |= MSI_ADDR_DEST_ID_CPU(cpu_physical_id(cpu)); dmar_msi_write(irq, &msg); - cpumask_copy(irq_data_get_affinity_mask(data), mask); + irq_data_update_affinity(data, mask); return 0; } diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c index 0fe2d79fb123..5ebb1771b4ab 100644 --- a/arch/parisc/kernel/irq.c +++ b/arch/parisc/kernel/irq.c @@ -315,7 +315,7 @@ unsigned long txn_affinity_addr(unsigned int irq, int cpu) { #ifdef CONFIG_SMP struct irq_data *d = irq_get_irq_data(irq); - cpumask_copy(irq_data_get_affinity_mask(d), cpumask_of(cpu)); + irq_data_update_affinity(d, cpumask_of(cpu)); #endif return per_cpu(cpu_data, cpu).txn_addr; diff --git a/drivers/irqchip/irq-bcm6345-l1.c b/drivers/irqchip/irq-bcm6345-l1.c index 142a7431745f..6899e37810a8 100644 --- a/drivers/irqchip/irq-bcm6345-l1.c +++ b/drivers/irqchip/irq-bcm6345-l1.c @@ -216,11 +216,11 @@ static int bcm6345_l1_set_affinity(struct irq_data *d, enabled = intc->cpus[old_cpu]->enable_cache[word] & mask; if (enabled) __bcm6345_l1_mask(d); - cpumask_copy(irq_data_get_affinity_mask(d), dest); + irq_data_update_affinity(d, dest); if (enabled) __bcm6345_l1_unmask(d); } else { - cpumask_copy(irq_data_get_affinity_mask(d), dest); + irq_data_update_affinity(d, dest); } raw_spin_unlock_irqrestore(&intc->lock, flags); diff --git a/drivers/parisc/iosapic.c b/drivers/parisc/iosapic.c index 8a3b0c3a1e92..3a8c98615634 100644 --- a/drivers/parisc/iosapic.c +++ b/drivers/parisc/iosapic.c @@ -677,7 +677,7 @@ static int iosapic_set_affinity_irq(struct irq_data *d, if (dest_cpu < 0) return -1; - cpumask_copy(irq_data_get_affinity_mask(d), cpumask_of(dest_cpu)); + irq_data_update_affinity(d, cpumask_of(dest_cpu)); vi->txn_addr = txn_affinity_addr(d->irq, dest_cpu); spin_lock_irqsave(&iosapic_lock, flags); diff --git a/drivers/sh/intc/chip.c b/drivers/sh/intc/chip.c index 358df7510186..828d81e02b37 100644 --- a/drivers/sh/intc/chip.c +++ b/drivers/sh/intc/chip.c @@ -72,7 +72,7 @@ static int intc_set_affinity(struct irq_data *data, if (!cpumask_intersects(cpumask, cpu_online_mask)) return -1; - cpumask_copy(irq_data_get_affinity_mask(data), cpumask); + irq_data_update_affinity(data, cpumask); return IRQ_SET_MASK_OK_NOCOPY; } diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 46d9295d9a6e..5e8321f43cbd 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -528,9 +528,10 @@ static void bind_evtchn_to_cpu(evtchn_port_t evtchn, unsigned int cpu, BUG_ON(irq == -1); if (IS_ENABLED(CONFIG_SMP) && force_affinity) { - cpumask_copy(irq_get_affinity_mask(irq), cpumask_of(cpu)); - cpumask_copy(irq_get_effective_affinity_mask(irq), - cpumask_of(cpu)); + struct irq_data *data = irq_get_irq_data(irq); + + irq_data_update_affinity(data, cpumask_of(cpu)); + irq_data_update_effective_affinity(data, cpumask_of(cpu)); } xen_evtchn_port_bind_to_cpu(evtchn, cpu, info->cpu); diff --git a/include/linux/irq.h b/include/linux/irq.h index 69ee4e2f36ce..adcfebceb777 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -884,6 +884,12 @@ static inline struct cpumask *irq_data_get_affinity_mask(struct irq_data *d) return d->common->affinity; } +static inline void irq_data_update_affinity(struct irq_data *d, + const struct cpumask *m) +{ + cpumask_copy(d->common->affinity, m); +} + static inline struct cpumask *irq_get_affinity_mask(int irq) { struct irq_data *d = irq_get_irq_data(irq); -- cgit v1.2.3-58-ga151 From de078949218242d57f791b63fac87cdb09cb0424 Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Fri, 1 Jul 2022 15:24:39 -0500 Subject: irqchip/sifive-plic: Make better use of the effective affinity mask The PLIC driver already updates the effective affinity mask in its .irq_set_affinity callback. Take advantage of that information to only touch bits (and take spinlocks) for the specific relevant hart contexts. First, make sure the effective affinity mask is set before IRQ startup. Then, since this mask already takes priv->lmask into account, checking that mask later is no longer needed (and handler->present is equivalent to the bit being set in priv->lmask). Finally, when (un)masking or changing affinity, only clear/set the enable bits in the specific old/new context(s). The cpumask operations in plic_irq_unmask() are not needed because they duplicate the code in plic_set_affinity(). Signed-off-by: Samuel Holland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220701202440.59059-2-samuel@sholland.org --- drivers/irqchip/Kconfig | 1 + drivers/irqchip/irq-sifive-plic.c | 27 +++++++++------------------ 2 files changed, 10 insertions(+), 18 deletions(-) (limited to 'drivers/irqchip') diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index 462adac905a6..ea7b7485327c 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -531,6 +531,7 @@ config SIFIVE_PLIC bool "SiFive Platform-Level Interrupt Controller" depends on RISCV select IRQ_DOMAIN_HIERARCHY + select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP help This enables support for the PLIC chip found in SiFive (and potentially other) RISC-V systems. The PLIC controls devices diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c index b3a36dca7f1b..46595e607b0e 100644 --- a/drivers/irqchip/irq-sifive-plic.c +++ b/drivers/irqchip/irq-sifive-plic.c @@ -114,31 +114,18 @@ static inline void plic_irq_toggle(const struct cpumask *mask, for_each_cpu(cpu, mask) { struct plic_handler *handler = per_cpu_ptr(&plic_handlers, cpu); - if (handler->present && - cpumask_test_cpu(cpu, &handler->priv->lmask)) - plic_toggle(handler, d->hwirq, enable); + plic_toggle(handler, d->hwirq, enable); } } static void plic_irq_unmask(struct irq_data *d) { - struct cpumask amask; - unsigned int cpu; - struct plic_priv *priv = irq_data_get_irq_chip_data(d); - - cpumask_and(&amask, &priv->lmask, cpu_online_mask); - cpu = cpumask_any_and(irq_data_get_affinity_mask(d), - &amask); - if (WARN_ON_ONCE(cpu >= nr_cpu_ids)) - return; - plic_irq_toggle(cpumask_of(cpu), d, 1); + plic_irq_toggle(irq_data_get_effective_affinity_mask(d), d, 1); } static void plic_irq_mask(struct irq_data *d) { - struct plic_priv *priv = irq_data_get_irq_chip_data(d); - - plic_irq_toggle(&priv->lmask, d, 0); + plic_irq_toggle(irq_data_get_effective_affinity_mask(d), d, 0); } #ifdef CONFIG_SMP @@ -159,11 +146,13 @@ static int plic_set_affinity(struct irq_data *d, if (cpu >= nr_cpu_ids) return -EINVAL; - plic_irq_toggle(&priv->lmask, d, 0); - plic_irq_toggle(cpumask_of(cpu), d, !irqd_irq_masked(d)); + plic_irq_mask(d); irq_data_update_effective_affinity(d, cpumask_of(cpu)); + if (!irqd_irq_masked(d)) + plic_irq_unmask(d); + return IRQ_SET_MASK_OK_DONE; } #endif @@ -190,6 +179,7 @@ static struct irq_chip plic_edge_chip = { .irq_set_affinity = plic_set_affinity, #endif .irq_set_type = plic_irq_set_type, + .flags = IRQCHIP_AFFINITY_PRE_STARTUP, }; static struct irq_chip plic_chip = { @@ -201,6 +191,7 @@ static struct irq_chip plic_chip = { .irq_set_affinity = plic_set_affinity, #endif .irq_set_type = plic_irq_set_type, + .flags = IRQCHIP_AFFINITY_PRE_STARTUP, }; static int plic_irq_set_type(struct irq_data *d, unsigned int type) -- cgit v1.2.3-58-ga151 From a1706a1c5062e0908528170f853601ed53f428c8 Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Fri, 1 Jul 2022 15:24:40 -0500 Subject: irqchip/sifive-plic: Separate the enable and mask operations The PLIC has two per-IRQ checks before sending an IRQ to a hart context. First, it checks that the IRQ's priority is nonzero. Then, it checks that the enable bit is set for that combination of IRQ and context. Currently, the PLIC driver sets both the priority value and the enable bit in its (un)mask operations. However, modifying the enable bit is problematic for two reasons: 1) The enable bits are packed, so changes are not atomic and require taking a spinlock. 2) The following requirement from the PLIC spec, which explains the racy (un)mask operations in plic_irq_eoi(): If the completion ID does not match an interrupt source that is currently enabled for the target, the completion is silently ignored. Both of these problems are solved by using the priority value to mask IRQs. Each IRQ has a separate priority register, so writing the priority value is atomic. And since the enable bit remains set while an IRQ is masked, the EOI operation works normally. The enable bits are still used to control the IRQ's affinity. Signed-off-by: Samuel Holland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220701202440.59059-3-samuel@sholland.org --- drivers/irqchip/irq-sifive-plic.c | 55 ++++++++++++++++++++++++--------------- 1 file changed, 34 insertions(+), 21 deletions(-) (limited to 'drivers/irqchip') diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c index 46595e607b0e..ba4938188570 100644 --- a/drivers/irqchip/irq-sifive-plic.c +++ b/drivers/irqchip/irq-sifive-plic.c @@ -108,9 +108,7 @@ static inline void plic_irq_toggle(const struct cpumask *mask, struct irq_data *d, int enable) { int cpu; - struct plic_priv *priv = irq_data_get_irq_chip_data(d); - writel(enable, priv->regs + PRIORITY_BASE + d->hwirq * PRIORITY_PER_ID); for_each_cpu(cpu, mask) { struct plic_handler *handler = per_cpu_ptr(&plic_handlers, cpu); @@ -118,16 +116,37 @@ static inline void plic_irq_toggle(const struct cpumask *mask, } } -static void plic_irq_unmask(struct irq_data *d) +static void plic_irq_enable(struct irq_data *d) { plic_irq_toggle(irq_data_get_effective_affinity_mask(d), d, 1); } -static void plic_irq_mask(struct irq_data *d) +static void plic_irq_disable(struct irq_data *d) { plic_irq_toggle(irq_data_get_effective_affinity_mask(d), d, 0); } +static void plic_irq_unmask(struct irq_data *d) +{ + struct plic_priv *priv = irq_data_get_irq_chip_data(d); + + writel(1, priv->regs + PRIORITY_BASE + d->hwirq * PRIORITY_PER_ID); +} + +static void plic_irq_mask(struct irq_data *d) +{ + struct plic_priv *priv = irq_data_get_irq_chip_data(d); + + writel(0, priv->regs + PRIORITY_BASE + d->hwirq * PRIORITY_PER_ID); +} + +static void plic_irq_eoi(struct irq_data *d) +{ + struct plic_handler *handler = this_cpu_ptr(&plic_handlers); + + writel(d->hwirq, handler->hart_base + CONTEXT_CLAIM); +} + #ifdef CONFIG_SMP static int plic_set_affinity(struct irq_data *d, const struct cpumask *mask_val, bool force) @@ -146,32 +165,21 @@ static int plic_set_affinity(struct irq_data *d, if (cpu >= nr_cpu_ids) return -EINVAL; - plic_irq_mask(d); + plic_irq_disable(d); irq_data_update_effective_affinity(d, cpumask_of(cpu)); - if (!irqd_irq_masked(d)) - plic_irq_unmask(d); + if (!irqd_irq_disabled(d)) + plic_irq_enable(d); return IRQ_SET_MASK_OK_DONE; } #endif -static void plic_irq_eoi(struct irq_data *d) -{ - struct plic_handler *handler = this_cpu_ptr(&plic_handlers); - - if (irqd_irq_masked(d)) { - plic_irq_unmask(d); - writel(d->hwirq, handler->hart_base + CONTEXT_CLAIM); - plic_irq_mask(d); - } else { - writel(d->hwirq, handler->hart_base + CONTEXT_CLAIM); - } -} - static struct irq_chip plic_edge_chip = { .name = "SiFive PLIC", + .irq_enable = plic_irq_enable, + .irq_disable = plic_irq_disable, .irq_ack = plic_irq_eoi, .irq_mask = plic_irq_mask, .irq_unmask = plic_irq_unmask, @@ -184,6 +192,8 @@ static struct irq_chip plic_edge_chip = { static struct irq_chip plic_chip = { .name = "SiFive PLIC", + .irq_enable = plic_irq_enable, + .irq_disable = plic_irq_disable, .irq_mask = plic_irq_mask, .irq_unmask = plic_irq_unmask, .irq_eoi = plic_irq_eoi, @@ -429,8 +439,11 @@ static int __init __plic_init(struct device_node *node, i * CONTEXT_ENABLE_SIZE; handler->priv = priv; done: - for (hwirq = 1; hwirq <= nr_irqs; hwirq++) + for (hwirq = 1; hwirq <= nr_irqs; hwirq++) { plic_toggle(handler, hwirq, 0); + writel(1, priv->regs + PRIORITY_BASE + + hwirq * PRIORITY_PER_ID); + } nr_handlers++; } -- cgit v1.2.3-58-ga151