From 07557ccb8c83f315e409ddee181e9ffbf87c6ad1 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 13 Sep 2017 23:29:05 +0200 Subject: [PATCH] genirq/msi: Capture device name for debugfs For debugging the allocation of unused or potentially leaked interrupt descriptor it's helpful to have some information about the site which allocated them. In case of MSI this is simple because the caller hands the device struct pointer into the domain allocation function. Duplicate the device name and show it in the debugfs entry of the interrupt descriptor. Signed-off-by: Thomas Gleixner Tested-by: Juergen Gross Tested-by: Yu Chen Acked-by: Juergen Gross Cc: Boris Ostrovsky Cc: Tony Luck Cc: Marc Zyngier Cc: Alok Kataria Cc: Joerg Roedel Cc: "Rafael J. Wysocki" Cc: Steven Rostedt Cc: Christoph Hellwig Cc: Peter Zijlstra Cc: Borislav Petkov Cc: Paolo Bonzini Cc: Rui Zhang Cc: "K. Y. Srinivasan" Cc: Arjan van de Ven Cc: Dan Williams Cc: Len Brown Link: https://lkml.kernel.org/r/20170913213152.433038426@linutronix.de --- include/linux/irqdesc.h | 1 + kernel/irq/debugfs.c | 10 ++++++++++ kernel/irq/internals.h | 5 +++++ kernel/irq/msi.c | 6 +++++- 4 files changed, 21 insertions(+), 1 deletion(-) diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h index 3e90a094798d..b55b113c049b 100644 --- a/include/linux/irqdesc.h +++ b/include/linux/irqdesc.h @@ -93,6 +93,7 @@ struct irq_desc { #endif #ifdef CONFIG_GENERIC_IRQ_DEBUGFS struct dentry *debugfs_file; + const char *dev_name; #endif #ifdef CONFIG_SPARSE_IRQ struct rcu_head rcu; diff --git a/kernel/irq/debugfs.c b/kernel/irq/debugfs.c index c3fdb36dec30..b7d1023b9b22 100644 --- a/kernel/irq/debugfs.c +++ b/kernel/irq/debugfs.c @@ -149,6 +149,7 @@ static int irq_debug_show(struct seq_file *m, void *p) raw_spin_lock_irq(&desc->lock); data = irq_desc_get_irq_data(desc); seq_printf(m, "handler: %pf\n", desc->handle_irq); + seq_printf(m, "device: %s\n", desc->dev_name); seq_printf(m, "status: 0x%08x\n", desc->status_use_accessors); irq_debug_show_bits(m, 0, desc->status_use_accessors, irqdesc_states, ARRAY_SIZE(irqdesc_states)); @@ -226,6 +227,15 @@ static const struct file_operations dfs_irq_ops = { .release = single_release, }; +void irq_debugfs_copy_devname(int irq, struct device *dev) +{ + struct irq_desc *desc = irq_to_desc(irq); + const char *name = dev_name(dev); + + if (name) + desc->dev_name = kstrdup(name, GFP_KERNEL); +} + void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc) { char name [10]; diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index a4aa39009f0d..cfaec2669093 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -443,7 +443,9 @@ void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc); static inline void irq_remove_debugfs_entry(struct irq_desc *desc) { debugfs_remove(desc->debugfs_file); + kfree(desc->dev_name); } +void irq_debugfs_copy_devname(int irq, struct device *dev); # ifdef CONFIG_IRQ_DOMAIN void irq_domain_debugfs_init(struct dentry *root); # else @@ -458,4 +460,7 @@ static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d) static inline void irq_remove_debugfs_entry(struct irq_desc *d) { } +static inline void irq_debugfs_copy_devname(int irq, struct device *dev) +{ +} #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */ diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index 3fa4bd59f569..94ecc0293844 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -16,6 +16,8 @@ #include #include +#include "internals.h" + /** * alloc_msi_entry - Allocate an initialize msi_entry * @dev: Pointer to the device for which this is allocated @@ -373,8 +375,10 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, return ret; } - for (i = 0; i < desc->nvec_used; i++) + for (i = 0; i < desc->nvec_used; i++) { irq_set_msi_desc_off(virq, i, desc); + irq_debugfs_copy_devname(virq + i, dev); + } } if (ops->msi_finish) -- 2.11.0