Re: [PATCH] IRQ resource deallocation[0/2]

From: Kenji Kaneshige <kaneshige.kenji_at_jp.fujitsu.com>
Date: 2004-12-10 17:13:40
I'm attching the updated set of patches.

Andrew, could you consider applying these patches?

Thanks,
Kenji Kaneshige

Zwane Mwaikambo wrote:

> On Tue, 7 Dec 2004, Kenji Kaneshige wrote:
> 
>> I had posted the IRQ resource deallocation patch a couple of monthes
>> ago and I had incorporated all feedbacks from the mailing list
>> (http://marc.theaimsgroup.com/?l=linux-kernel&m=109688530703122&w=2).
>> But it doesn't seems to be included yet, so I would like to try again.
>> I hope my patch is included onto -mm tree since I want the patches
>> be tested by many people.
> 
> You should remove the config option and make it unconditional.
> 
> Thanks,
> 	Zwane
> 
> 


Kernel Version:	2.6.10-rc3
Depends:	none
Description:

This patch is ACPI portion of IRQ deallocation. This patch defines the
following new interface. The implementation of this interface depends
on each platform.

    o void acpi_unregister_gsi(u32 gsi)

        This is a opposite portion of acpi_register_gsi(). This has a
        responsibility for deallocating IRQ resources associated with
        the specified GSI number.

        We need to consider the case of shared interrupt. In the case
        of shared interrupt, acpi_register_gsi() is called multiple
        times for one gsi. That is, registrations and unregistrations
        can be nested.

        This function undoes the effect of one call to
        acpi_register_gsi(). If this matches the last registration,
        IRQ resources associated with the specified GSI number are
        freed.

This patch also adds the following new function.

    o void acpi_pci_irq_disable (struct pci_dev *dev)

        This function is a opposite portion of
        acpi_pci_enable_irq(). It clears the device's linux IRQ number
        and calls acpi_unregister_gsi() to deallocate IRQ resources.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>


---

 linux-2.6.10-rc3-kanesige/drivers/acpi/pci_irq.c |   52 +++++++++++++++++++++++
 linux-2.6.10-rc3-kanesige/include/linux/acpi.h   |   13 +++++
 2 files changed, 65 insertions(+)

diff -puN drivers/acpi/pci_irq.c~IRQ_deallocation_acpi drivers/acpi/pci_irq.c
--- linux-2.6.10-rc3/drivers/acpi/pci_irq.c~IRQ_deallocation_acpi	2004-12-06 19:51:50.274759676 +0900
+++ linux-2.6.10-rc3-kanesige/drivers/acpi/pci_irq.c	2004-12-06 19:54:43.254430880 +0900
@@ -407,3 +407,55 @@ acpi_pci_irq_enable (
 }
 EXPORT_SYMBOL(acpi_pci_irq_enable);
 
+
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+void
+acpi_pci_irq_disable (
+	struct pci_dev		*dev)
+{
+	u32			gsi = 0;
+	u8			pin = 0;
+	int			edge_level = ACPI_LEVEL_SENSITIVE;
+	int			active_high_low = ACPI_ACTIVE_LOW;
+
+	ACPI_FUNCTION_TRACE("acpi_pci_irq_disable");
+
+	if (!dev)
+		return_VOID;
+	
+	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
+	if (!pin)
+		return_VOID;
+	pin--;
+
+	if (!dev->bus)
+		return_VOID;
+
+	/* 
+	 * First we check the PCI IRQ routing table (PRT) for an IRQ.
+	 */
+ 	gsi = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
+				  &edge_level, &active_high_low);
+	/*
+	 * If no PRT entry was found, we'll try to derive an IRQ from the
+	 * device's parent bridge.
+	 */
+	if (!gsi)
+ 		gsi = acpi_pci_irq_derive(dev, pin,
+					  &edge_level, &active_high_low);
+	if (!gsi)
+		return_VOID;
+
+	/*
+	 * TBD: It might be worth clearing dev->irq by magic constant
+	 * (e.g. PCI_UNDEFINED_IRQ).
+	 */
+
+	printk(KERN_INFO PREFIX "PCI interrupt for device %s disabled\n",
+	       pci_name(dev));
+
+	acpi_unregister_gsi(gsi);
+
+	return_VOID;
+}
+#endif /* CONFIG_ACPI_DEALLOCATE_IRQ */
diff -puN include/linux/acpi.h~IRQ_deallocation_acpi include/linux/acpi.h
--- linux-2.6.10-rc3/include/linux/acpi.h~IRQ_deallocation_acpi	2004-12-06 19:51:50.276712814 +0900
+++ linux-2.6.10-rc3-kanesige/include/linux/acpi.h	2004-12-06 19:51:50.279642521 +0900
@@ -416,6 +416,15 @@ static inline int acpi_boot_init(void)
 unsigned int acpi_register_gsi (u32 gsi, int edge_level, int active_high_low);
 int acpi_gsi_to_irq (u32 gsi, unsigned int *irq);
 
+/*
+ * This function undoes the effect of one call to acpi_register_gsi().
+ * If this matches the last registration, any IRQ resources for gsi
+ * are freed.
+ */
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+void acpi_unregister_gsi (u32 gsi);
+#endif
+
 #ifdef CONFIG_ACPI_PCI
 
 struct acpi_prt_entry {
@@ -441,6 +450,10 @@ struct pci_dev;
 int acpi_pci_irq_enable (struct pci_dev *dev);
 void acpi_penalize_isa_irq(int irq);
 
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+void acpi_pci_irq_disable (struct pci_dev *dev);
+#endif
+
 struct acpi_pci_driver {
 	struct acpi_pci_driver *next;
 	int (*add)(acpi_handle handle);

_


Kernel Version:	2.6.10-rc3
Depends:	IRQ_deallocation_acpi.patch
Description:

This is an ia64 portion of IRQ resource deallocation. It implements
pcibios_disable_device() and acpi_unregister_gsi() for ia64.

    o acpi_unregister_gsi()

        Summary of changes for implementing this interface:

        - Add new function iosapic_unregister_intr() into
          arch/ia64/kernel/iosapic.c. This function frees an interrupt
          vector and related data structures.

        - Add new function free_irq_vector() into
          arch/ia64/kernel/irq_ia64.c. This frees an unused vector.

        - Change assign_irq_vector() to be able to support
          free_irq_vector().

    o pcibios_disable_device()

        This calls acpi_pci_irq_disable() to deallocate IRQ resources.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>


---

 linux-2.6.10-rc3-kanesige/arch/ia64/Kconfig           |    5 
 linux-2.6.10-rc3-kanesige/arch/ia64/kernel/acpi.c     |    9 +
 linux-2.6.10-rc3-kanesige/arch/ia64/kernel/iosapic.c  |   96 ++++++++++++++++--
 linux-2.6.10-rc3-kanesige/arch/ia64/kernel/irq.c      |    3 
 linux-2.6.10-rc3-kanesige/arch/ia64/kernel/irq_ia64.c |   27 ++++-
 linux-2.6.10-rc3-kanesige/arch/ia64/pci/pci.c         |    8 +
 linux-2.6.10-rc3-kanesige/include/asm-ia64/hw_irq.h   |    2 
 linux-2.6.10-rc3-kanesige/include/asm-ia64/iosapic.h  |    4 
 8 files changed, 141 insertions(+), 13 deletions(-)

diff -puN arch/ia64/Kconfig~IRQ_deallocation_ia64 arch/ia64/Kconfig
--- linux-2.6.10-rc3/arch/ia64/Kconfig~IRQ_deallocation_ia64	2004-12-06 19:58:12.000000000 +0900
+++ linux-2.6.10-rc3-kanesige/arch/ia64/Kconfig	2004-12-08 14:01:29.040576358 +0900
@@ -302,6 +302,11 @@ config IA64_PALINFO
 	  To use this option, you have to ensure that the "/proc file system
 	  support" (CONFIG_PROC_FS) is enabled, too.
 
+config ACPI_DEALLOCATE_IRQ
+	bool
+	depends on IOSAPIC && EXPERIMENTAL
+	default y
+
 source "drivers/firmware/Kconfig"
 
 source "fs/Kconfig.binfmt"
diff -puN arch/ia64/kernel/acpi.c~IRQ_deallocation_ia64 arch/ia64/kernel/acpi.c
--- linux-2.6.10-rc3/arch/ia64/kernel/acpi.c~IRQ_deallocation_ia64	2004-12-06 19:58:12.000000000 +0900
+++ linux-2.6.10-rc3-kanesige/arch/ia64/kernel/acpi.c	2004-12-06 19:58:12.000000000 +0900
@@ -517,6 +517,15 @@ acpi_register_gsi (u32 gsi, int edge_lev
 }
 EXPORT_SYMBOL(acpi_register_gsi);
 
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+void
+acpi_unregister_gsi (u32 gsi)
+{
+	iosapic_unregister_intr(gsi);
+}
+EXPORT_SYMBOL(acpi_unregister_gsi);
+#endif /* CONFIG_ACPI_DEALLOCATE_IRQ */
+
 static int __init
 acpi_parse_fadt (unsigned long phys_addr, unsigned long size)
 {
diff -puN arch/ia64/kernel/iosapic.c~IRQ_deallocation_ia64 arch/ia64/kernel/iosapic.c
--- linux-2.6.10-rc3/arch/ia64/kernel/iosapic.c~IRQ_deallocation_ia64	2004-12-06 19:58:12.000000000 +0900
+++ linux-2.6.10-rc3-kanesige/arch/ia64/kernel/iosapic.c	2004-12-06 19:58:12.000000000 +0900
@@ -111,6 +111,7 @@ static struct iosapic_intr_info {
 	unsigned char	dmode	: 3;	/* delivery mode (see iosapic.h) */
 	unsigned char 	polarity: 1;	/* interrupt polarity (see iosapic.h) */
 	unsigned char	trigger	: 1;	/* trigger mode (see iosapic.h) */
+	int		refcnt;		/* reference counter */
 } iosapic_intr_info[IA64_NUM_VECTORS];
 
 static struct iosapic {
@@ -177,7 +178,7 @@ gsi_to_irq (unsigned int gsi)
 static void
 set_rte (unsigned int vector, unsigned int dest, int mask)
 {
-	unsigned long pol, trigger, dmode, flags;
+	unsigned long pol, trigger, dmode;
 	u32 low32, high32;
 	char __iomem *addr;
 	int rte_index;
@@ -218,13 +219,9 @@ set_rte (unsigned int vector, unsigned i
 	/* dest contains both id and eid */
 	high32 = (dest << IOSAPIC_DEST_SHIFT);
 
-	spin_lock_irqsave(&iosapic_lock, flags);
-	{
-		iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
-		iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
-		iosapic_intr_info[vector].low32 = low32;
-	}
-	spin_unlock_irqrestore(&iosapic_lock, flags);
+	iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
+	iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
+	iosapic_intr_info[vector].low32 = low32;
 }
 
 static void
@@ -475,6 +472,7 @@ register_intr (unsigned int gsi, int vec
 	iosapic_intr_info[vector].addr     = iosapic_address;
 	iosapic_intr_info[vector].gsi_base = gsi_base;
 	iosapic_intr_info[vector].trigger  = trigger;
+	iosapic_intr_info[vector].refcnt++;
 
 	if (trigger == IOSAPIC_EDGE)
 		irq_type = &irq_type_iosapic_edge;
@@ -581,6 +579,7 @@ iosapic_register_intr (unsigned int gsi,
 	{
 		vector = gsi_to_vector(gsi);
 		if (vector > 0) {
+			iosapic_intr_info[vector].refcnt++;
 			spin_unlock_irqrestore(&iosapic_lock, flags);
 			return vector;
 		}
@@ -589,6 +588,8 @@ iosapic_register_intr (unsigned int gsi,
 		dest = get_target_cpu(gsi, vector);
 		register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
 			polarity, trigger);
+
+		set_rte(vector, dest, 1);
 	}
 	spin_unlock_irqrestore(&iosapic_lock, flags);
 
@@ -597,10 +598,87 @@ iosapic_register_intr (unsigned int gsi,
 	       (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
 	       cpu_logical_id(dest), dest, vector);
 
-	set_rte(vector, dest, 1);
 	return vector;
 }
 
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+void
+iosapic_unregister_intr (unsigned int gsi)
+{
+	unsigned long flags;
+	int irq, vector;
+	irq_desc_t *idesc;
+	int rte_index;
+	unsigned long trigger, polarity;
+	
+	/*
+	 * If the irq associated with the gsi is not found,
+	 * iosapic_unregister_intr() is unbalanced. We need to check
+	 * this again after getting locks.
+	 */
+	irq = gsi_to_irq(gsi);
+	if (irq < 0) {
+		printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
+		WARN_ON(1);
+		return;
+	}
+	vector = irq_to_vector(irq);
+
+	idesc = irq_descp(irq);
+	spin_lock_irqsave(&idesc->lock, flags);
+	spin_lock(&iosapic_lock);
+	{
+		rte_index = iosapic_intr_info[vector].rte_index;
+		if (rte_index < 0) {
+			spin_unlock(&iosapic_lock);
+			spin_unlock_irqrestore(&idesc->lock, flags);
+			printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
+			WARN_ON(1);
+			return;
+		}
+
+		if (--iosapic_intr_info[vector].refcnt > 0) {
+			spin_unlock(&iosapic_lock);
+			spin_unlock_irqrestore(&idesc->lock, flags);
+			return;
+		}
+
+		/*
+		 * If interrupt handlers still exist on the irq
+		 * associated with the gsi, don't unregister the
+		 * interrupt.
+		 */
+		if (idesc->action) {
+			iosapic_intr_info[vector].refcnt++;
+			spin_unlock(&iosapic_lock);
+			spin_unlock_irqrestore(&idesc->lock, flags);
+			printk(KERN_WARNING "Cannot unregister GSI. IRQ %u is still in use.\n", irq);
+			return;
+		}
+
+		/* Clear the interrupt controller descriptor. */
+		idesc->handler = &no_irq_type;
+
+		trigger  = iosapic_intr_info[vector].trigger;
+		polarity = iosapic_intr_info[vector].polarity;
+
+		/* Clear the interrupt information. */
+		memset(&iosapic_intr_info[vector], 0, sizeof(struct iosapic_intr_info));
+		iosapic_intr_info[vector].rte_index = -1;	/* mark as unused */
+	}
+	spin_unlock(&iosapic_lock);
+	spin_unlock_irqrestore(&idesc->lock, flags);
+
+	/* Free the interrupt vector */
+	free_irq_vector(vector);
+
+	printk(KERN_INFO "GSI %u (%s, %s) -> vector %d unregisterd.\n",
+	       gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
+	       (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
+	       vector);
+}
+#endif /* CONFIG_ACPI_DEALLOCATE_IRQ */
+
 /*
  * ACPI calls this when it finds an entry for a platform interrupt.
  * Note that the irq_base and IOSAPIC address must be set in iosapic_init().
diff -puN arch/ia64/kernel/irq.c~IRQ_deallocation_ia64 arch/ia64/kernel/irq.c
--- linux-2.6.10-rc3/arch/ia64/kernel/irq.c~IRQ_deallocation_ia64	2004-12-06 19:58:12.000000000 +0900
+++ linux-2.6.10-rc3-kanesige/arch/ia64/kernel/irq.c	2004-12-06 19:58:12.000000000 +0900
@@ -1030,6 +1030,9 @@ void move_irq(int irq)
 	irq_desc_t *desc = irq_descp(irq);
 	int redir = test_bit(irq, pending_irq_redir);
 
+	if (unlikely(!desc->handler->set_affinity))
+		return;
+
 	if (!cpus_empty(pending_irq_cpumask[irq])) {
 		cpus_and(tmp, pending_irq_cpumask[irq], cpu_online_map);
 		if (unlikely(!cpus_empty(tmp))) {
diff -puN arch/ia64/kernel/irq_ia64.c~IRQ_deallocation_ia64 arch/ia64/kernel/irq_ia64.c
--- linux-2.6.10-rc3/arch/ia64/kernel/irq_ia64.c~IRQ_deallocation_ia64	2004-12-06 19:58:12.000000000 +0900
+++ linux-2.6.10-rc3-kanesige/arch/ia64/kernel/irq_ia64.c	2004-12-06 19:58:12.000000000 +0900
@@ -75,15 +75,34 @@ irq_exit (void)
 	preempt_enable_no_resched();
 }
 
+static unsigned long ia64_vector_mask[BITS_TO_LONGS(IA64_NUM_DEVICE_VECTORS)];
+
 int
 assign_irq_vector (int irq)
 {
-	static int next_vector = IA64_FIRST_DEVICE_VECTOR;
-
-	if (next_vector > IA64_LAST_DEVICE_VECTOR)
+	int pos, vector;
+ again:
+	pos = find_first_zero_bit(ia64_vector_mask, IA64_NUM_DEVICE_VECTORS);
+	vector = IA64_FIRST_DEVICE_VECTOR + pos;
+	if (vector > IA64_LAST_DEVICE_VECTOR)
 		/* XXX could look for sharable vectors instead of panic'ing... */
 		panic("assign_irq_vector: out of interrupt vectors!");
-	return next_vector++;
+	if (test_and_set_bit(pos, ia64_vector_mask))
+		goto again;
+	return vector;
+}
+
+void
+free_irq_vector (int vector)
+{
+	int pos;
+
+	if (vector < IA64_FIRST_DEVICE_VECTOR || vector > IA64_LAST_DEVICE_VECTOR)
+		return;
+
+	pos = vector - IA64_FIRST_DEVICE_VECTOR;
+	if (!test_and_clear_bit(pos, ia64_vector_mask))
+		printk(KERN_WARNING "%s: double free!\n", __FUNCTION__);
 }
 
 extern unsigned int do_IRQ(unsigned long irq, struct pt_regs *regs);
diff -puN arch/ia64/pci/pci.c~IRQ_deallocation_ia64 arch/ia64/pci/pci.c
--- linux-2.6.10-rc3/arch/ia64/pci/pci.c~IRQ_deallocation_ia64	2004-12-06 19:58:12.000000000 +0900
+++ linux-2.6.10-rc3-kanesige/arch/ia64/pci/pci.c	2004-12-06 19:58:12.000000000 +0900
@@ -480,6 +480,14 @@ pcibios_enable_device (struct pci_dev *d
 	return acpi_pci_irq_enable(dev);
 }
 
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+void
+pcibios_disable_device (struct pci_dev *dev)
+{
+	acpi_pci_irq_disable(dev);
+}
+#endif /* CONFIG_ACPI_DEALLOCATE_IRQ */
+
 void
 pcibios_align_resource (void *data, struct resource *res,
 		        unsigned long size, unsigned long align)
diff -puN include/asm-ia64/hw_irq.h~IRQ_deallocation_ia64 include/asm-ia64/hw_irq.h
--- linux-2.6.10-rc3/include/asm-ia64/hw_irq.h~IRQ_deallocation_ia64	2004-12-06 19:58:12.000000000 +0900
+++ linux-2.6.10-rc3-kanesige/include/asm-ia64/hw_irq.h	2004-12-06 19:58:12.000000000 +0900
@@ -50,6 +50,7 @@ typedef u8 ia64_vector;
  */
 #define IA64_FIRST_DEVICE_VECTOR	0x30
 #define IA64_LAST_DEVICE_VECTOR		0xe7
+#define IA64_NUM_DEVICE_VECTORS		(IA64_LAST_DEVICE_VECTOR - IA64_FIRST_DEVICE_VECTOR + 1)
 
 #define IA64_MCA_RENDEZ_VECTOR		0xe8	/* MCA rendez interrupt */
 #define IA64_PERFMON_VECTOR		0xee	/* performanc monitor interrupt vector */
@@ -81,6 +82,7 @@ extern __u8 isa_irq_to_vector_map[16];
 extern struct hw_interrupt_type irq_type_ia64_lsapic;	/* CPU-internal interrupt controller */
 
 extern int assign_irq_vector (int irq);	/* allocate a free vector */
+extern void free_irq_vector (int vector);
 extern void ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect);
 extern void register_percpu_irq (ia64_vector vec, struct irqaction *action);
 
diff -puN include/asm-ia64/iosapic.h~IRQ_deallocation_ia64 include/asm-ia64/iosapic.h
--- linux-2.6.10-rc3/include/asm-ia64/iosapic.h~IRQ_deallocation_ia64	2004-12-06 19:58:12.000000000 +0900
+++ linux-2.6.10-rc3-kanesige/include/asm-ia64/iosapic.h	2004-12-06 19:58:12.000000000 +0900
@@ -78,6 +78,9 @@ extern int gsi_to_irq (unsigned int gsi)
 extern void iosapic_enable_intr (unsigned int vector);
 extern int iosapic_register_intr (unsigned int gsi, unsigned long polarity,
 				  unsigned long trigger);
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+extern void iosapic_unregister_intr (unsigned int irq);
+#endif
 extern void __init iosapic_override_isa_irq (unsigned int isa_irq, unsigned int gsi,
 				      unsigned long polarity,
 				      unsigned long trigger);
@@ -97,6 +100,7 @@ extern void __init map_iosapic_to_node (
 #define iosapic_system_init(pcat_compat)			do { } while (0)
 #define iosapic_init(address,gsi_base)				do { } while (0)
 #define iosapic_register_intr(gsi,polarity,trigger)		(gsi)
+#define iosapic_unregister_intr(irq)				do { } while (0)
 #define iosapic_override_isa_irq(isa_irq,gsi,polarity,trigger)	do { } while (0)
 #define iosapic_register_platform_intr(type,gsi,pmi,eid,id, \
 	polarity,trigger)					(gsi)

_


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Received on Fri Dec 10 01:15:54 2004

This archive was generated by hypermail 2.1.8 : 2005-08-02 09:20:33 EST