From fe3464ca8710012a247bb4586dde21b080f88514 Mon Sep 17 00:00:00 2001 From: Jianyu Zhan Date: Sat, 19 Mar 2016 21:59:19 +0800 Subject: genirq: Remove redundant NULL check of irq_desc for_each_irq_desc() macro has already skipped NULL irq_desc, don't bother to check it again. Signed-off-by: Jianyu Zhan Cc: mingo@kernel.org Cc: yhlu.kernel@gmail.com Link: http://lkml.kernel.org/r/1458395959-7046-1-git-send-email-nasa4836@gmail.com Signed-off-by: Thomas Gleixner --- kernel/irq/proc.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'kernel/irq/proc.c') diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 4e1b94726818..50a8f28be247 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -421,12 +421,8 @@ void init_irq_proc(void) /* * Create entries for all existing IRQs. */ - for_each_irq_desc(irq, desc) { - if (!desc) - continue; - + for_each_irq_desc(irq, desc) register_irq_proc(irq, desc); - } } #ifdef CONFIG_GENERIC_IRQ_SHOW -- cgit v1.2.3-70-g09d2 From ff5b706f5189fe8d2a6fd576b491b769ec1d29d3 Mon Sep 17 00:00:00 2001 From: Weongyo Jeong Date: Thu, 31 Mar 2016 12:15:03 -0700 Subject: genirq: Remove unnecessary memset() calls sprintf() and snprintf() implementation of kernel guarantees that its result is terminated with null byte if size is larger than 0. So we don't need to call memset() at all. Signed-off-by: Weongyo Jeong Link: http://lkml.kernel.org/r/1459451703-5744-1-git-send-email-weongyo.linux@gmail.com Signed-off-by: Thomas Gleixner --- kernel/irq/proc.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'kernel/irq/proc.c') diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 50a8f28be247..f30425dce9dd 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -311,7 +311,6 @@ void register_handler_proc(unsigned int irq, struct irqaction *action) !name_unique(irq, action)) return; - memset(name, 0, MAX_NAMELEN); snprintf(name, MAX_NAMELEN, "%s", action->name); /* create /proc/irq/1234/handler/ */ @@ -340,7 +339,6 @@ void register_irq_proc(unsigned int irq, struct irq_desc *desc) if (desc->dir) goto out_unlock; - memset(name, 0, MAX_NAMELEN); sprintf(name, "%d", irq); /* create /proc/irq/1234 */ @@ -386,7 +384,6 @@ void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) #endif remove_proc_entry("spurious", desc->dir); - memset(name, 0, MAX_NAMELEN); sprintf(name, "%u", irq); remove_proc_entry(name, root_irq_dir); } -- cgit v1.2.3-70-g09d2 From 9c2555835bb3d34dfac52a0be943dcc4bedd650f Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 4 Jul 2016 17:39:23 +0900 Subject: genirq: Introduce IRQD_AFFINITY_MANAGED flag Interupts marked with this flag are excluded from user space interrupt affinity changes. Contrary to the IRQ_NO_BALANCING flag, the kernel internal affinity mechanism is not blocked. This flag will be used for multi-queue device interrupts. Signed-off-by: Thomas Gleixner Cc: Christoph Hellwig Cc: linux-block@vger.kernel.org Cc: linux-pci@vger.kernel.org Cc: linux-nvme@lists.infradead.org Cc: axboe@fb.com Cc: agordeev@redhat.com Link: http://lkml.kernel.org/r/1467621574-8277-3-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner --- include/linux/irq.h | 7 +++++++ kernel/irq/internals.h | 2 ++ kernel/irq/manage.c | 21 ++++++++++++++++++--- kernel/irq/proc.c | 2 +- 4 files changed, 28 insertions(+), 4 deletions(-) (limited to 'kernel/irq/proc.c') diff --git a/include/linux/irq.h b/include/linux/irq.h index 4d758a7c604a..f6074813688d 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -197,6 +197,7 @@ struct irq_data { * IRQD_IRQ_INPROGRESS - In progress state of the interrupt * IRQD_WAKEUP_ARMED - Wakeup mode armed * IRQD_FORWARDED_TO_VCPU - The interrupt is forwarded to a VCPU + * IRQD_AFFINITY_MANAGED - Affinity is auto-managed by the kernel */ enum { IRQD_TRIGGER_MASK = 0xf, @@ -212,6 +213,7 @@ enum { IRQD_IRQ_INPROGRESS = (1 << 18), IRQD_WAKEUP_ARMED = (1 << 19), IRQD_FORWARDED_TO_VCPU = (1 << 20), + IRQD_AFFINITY_MANAGED = (1 << 21), }; #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors) @@ -305,6 +307,11 @@ static inline void irqd_clr_forwarded_to_vcpu(struct irq_data *d) __irqd_to_state(d) &= ~IRQD_FORWARDED_TO_VCPU; } +static inline bool irqd_affinity_is_managed(struct irq_data *d) +{ + return __irqd_to_state(d) & IRQD_AFFINITY_MANAGED; +} + #undef __irqd_to_state static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index 09be2c903c6d..b15aa3b617a2 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -105,6 +105,8 @@ static inline void unregister_handler_proc(unsigned int irq, struct irqaction *action) { } #endif +extern bool irq_can_set_affinity_usr(unsigned int irq); + extern int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask); extern void irq_set_thread_affinity(struct irq_desc *desc); diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index ef0bc02c3a70..30658e9827f0 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -115,12 +115,12 @@ EXPORT_SYMBOL(synchronize_irq); #ifdef CONFIG_SMP cpumask_var_t irq_default_affinity; -static int __irq_can_set_affinity(struct irq_desc *desc) +static bool __irq_can_set_affinity(struct irq_desc *desc) { if (!desc || !irqd_can_balance(&desc->irq_data) || !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity) - return 0; - return 1; + return false; + return true; } /** @@ -133,6 +133,21 @@ int irq_can_set_affinity(unsigned int irq) return __irq_can_set_affinity(irq_to_desc(irq)); } +/** + * irq_can_set_affinity_usr - Check if affinity of a irq can be set from user space + * @irq: Interrupt to check + * + * Like irq_can_set_affinity() above, but additionally checks for the + * AFFINITY_MANAGED flag. + */ +bool irq_can_set_affinity_usr(unsigned int irq) +{ + struct irq_desc *desc = irq_to_desc(irq); + + return __irq_can_set_affinity(desc) && + !irqd_affinity_is_managed(&desc->irq_data); +} + /** * irq_set_thread_affinity - Notify irq threads to adjust affinity * @desc: irq descriptor which has affitnity changed diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 4e1b94726818..40bdcdc1f700 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -96,7 +96,7 @@ static ssize_t write_irq_affinity(int type, struct file *file, cpumask_var_t new_value; int err; - if (!irq_can_set_affinity(irq) || no_irq_affinity) + if (!irq_can_set_affinity_usr(irq) || no_irq_affinity) return -EIO; if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) -- cgit v1.2.3-70-g09d2