[PATCH 1/5] irq: remove not need bootmem code

[PATCH 1/5] irq: remove not need bootmem code

[Yinghai Lu]

mem_init is moved early already.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 kernel/irq/handle.c |   14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

Index: linux-2.6/kernel/irq/handle.c
===================================================================
--- linux-2.6.orig/kernel/irq/handle.c
+++ linux-2.6/kernel/irq/handle.c
@@ -19,7 +19,6 @@
 #include <linux/kernel_stat.h>
 #include <linux/rculist.h>
 #include <linux/hash.h>
-#include <linux/bootmem.h>
 #include <trace/events/irq.h>
 
 #include "internals.h"
@@ -87,12 +86,8 @@ void __ref init_kstat_irqs(struct irq_de
 {
 	void *ptr;
 
-	if (slab_is_available())
-		ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs),
-				   GFP_ATOMIC, node);
-	else
-		ptr = alloc_bootmem_node(NODE_DATA(node),
-				nr * sizeof(*desc->kstat_irqs));
+	ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs),
+			   GFP_ATOMIC, node);
 
 	/*
 	 * don't overwite if can not get new one
@@ -219,10 +214,7 @@ struct irq_desc * __ref irq_to_desc_allo
 	if (desc)
 		goto out_unlock;
 
-	if (slab_is_available())
-		desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
-	else
-		desc = alloc_bootmem_node(NODE_DATA(node), sizeof(*desc));
+	desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
 
 	printk(KERN_DEBUG "  alloc irq_desc for %d on node %d\n", irq, node);
 	if (!desc) {

[PATCH 2/5] radix: move radix init early

[Yinghai Lu]

prepare to use it in early_irq_init()

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 init/main.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6/init/main.c
===================================================================
--- linux-2.6.orig/init/main.c
+++ linux-2.6/init/main.c
@@ -584,6 +584,7 @@ asmlinkage void __init start_kernel(void
 		local_irq_disable();
 	}
 	rcu_init();
+	radix_tree_init();
 	/* init some links before init_ISA_irqs() */
 	early_irq_init();
 	init_IRQ();
@@ -659,7 +660,6 @@ asmlinkage void __init start_kernel(void
 	key_init();
 	security_init();
 	vfs_caches_init(totalram_pages);
-	radix_tree_init();
 	signals_init();
 	/* rootfs populating might need page-writeback */
 	page_writeback_init();

[PATCH 3/5] sparseirq: change irq_desc_ptrs to static

[Yinghai Lu]

add replace_irq_desc()

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 kernel/irq/handle.c       |    8 +++++++-
 kernel/irq/internals.h    |    6 +-----
 kernel/irq/numa_migrate.c |    4 ++--
 3 files changed, 10 insertions(+), 8 deletions(-)

Index: linux-2.6/kernel/irq/handle.c
===================================================================
--- linux-2.6.orig/kernel/irq/handle.c
+++ linux-2.6/kernel/irq/handle.c
@@ -127,7 +127,7 @@ static void init_one_irq_desc(int irq, s
  */
 DEFINE_RAW_SPINLOCK(sparse_irq_lock);
 
-struct irq_desc **irq_desc_ptrs __read_mostly;
+static struct irq_desc **irq_desc_ptrs __read_mostly;
 
 static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = {
 	[0 ... NR_IRQS_LEGACY-1] = {
@@ -192,6 +192,12 @@ struct irq_desc *irq_to_desc(unsigned in
 	return NULL;
 }
 
+void replace_irq_desc(unsigned int irq, struct irq_desc *desc)
+{
+	if (irq_desc_ptrs && irq < nr_irqs)
+		irq_desc_ptrs[irq] = desc;
+}
+
 struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node)
 {
 	struct irq_desc *desc;
Index: linux-2.6/kernel/irq/internals.h
===================================================================
--- linux-2.6.orig/kernel/irq/internals.h
+++ linux-2.6/kernel/irq/internals.h
@@ -21,11 +21,7 @@ extern void clear_kstat_irqs(struct irq_
 extern raw_spinlock_t sparse_irq_lock;
 
 #ifdef CONFIG_SPARSE_IRQ
-/* irq_desc_ptrs allocated at boot time */
-extern struct irq_desc **irq_desc_ptrs;
-#else
-/* irq_desc_ptrs is a fixed size array */
-extern struct irq_desc *irq_desc_ptrs[NR_IRQS];
+void replace_irq_desc(unsigned int irq, struct irq_desc *desc);
 #endif
 
 #ifdef CONFIG_PROC_FS
Index: linux-2.6/kernel/irq/numa_migrate.c
===================================================================
--- linux-2.6.orig/kernel/irq/numa_migrate.c
+++ linux-2.6/kernel/irq/numa_migrate.c
@@ -70,7 +70,7 @@ static struct irq_desc *__real_move_irq_
 	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
 
 	/* We have to check it to avoid races with another CPU */
-	desc = irq_desc_ptrs[irq];
+	desc = irq_to_desc(irq);
 
 	if (desc && old_desc != desc)
 		goto out_unlock;
@@ -90,7 +90,7 @@ static struct irq_desc *__real_move_irq_
 		goto out_unlock;
 	}
 
-	irq_desc_ptrs[irq] = desc;
+	replace_irq_desc(irq, desc);
 	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);
 
 	/* free the old one */

[PATCH -v2 4/5] sparseirq: use radix_tree instead of ptrs array

[Yinghai Lu]

use radix_tree irq_desc_tree instead of irq_desc_ptrs.

-v2: according to Eric and cyrill to use radix_tree_lookup_slot and radix_tree_replace_slot

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 kernel/irq/handle.c |   50 +++++++++++++++++++++++++-------------------------
 1 file changed, 25 insertions(+), 25 deletions(-)

Index: linux-2.6/kernel/irq/handle.c
===================================================================
--- linux-2.6.orig/kernel/irq/handle.c
+++ linux-2.6/kernel/irq/handle.c
@@ -19,6 +19,7 @@
 #include <linux/kernel_stat.h>
 #include <linux/rculist.h>
 #include <linux/hash.h>
+#include <linux/radix-tree.h>
 #include <trace/events/irq.h>
 
 #include "internals.h"
@@ -127,7 +128,26 @@ static void init_one_irq_desc(int irq, s
  */
 DEFINE_RAW_SPINLOCK(sparse_irq_lock);
 
-static struct irq_desc **irq_desc_ptrs __read_mostly;
+static RADIX_TREE(irq_desc_tree, GFP_ATOMIC);
+
+static void set_irq_desc(unsigned int irq, struct irq_desc *desc)
+{
+	radix_tree_insert(&irq_desc_tree, irq, desc);
+}
+
+struct irq_desc *irq_to_desc(unsigned int irq)
+{
+	return radix_tree_lookup(&irq_desc_tree, irq);
+}
+
+void replace_irq_desc(unsigned int irq, struct irq_desc *desc)
+{
+	void **ptr;
+
+	ptr = radix_tree_lookup_slot(&irq_desc_tree, irq);
+	if (ptr)
+		radix_tree_replace_slot(ptr, desc);
+}
 
 static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = {
 	[0 ... NR_IRQS_LEGACY-1] = {
@@ -159,9 +179,6 @@ int __init early_irq_init(void)
 	legacy_count = ARRAY_SIZE(irq_desc_legacy);
 	node = first_online_node;
 
-	/* allocate irq_desc_ptrs array based on nr_irqs */
-	irq_desc_ptrs = kcalloc(nr_irqs, sizeof(void *), GFP_NOWAIT);
-
 	/* allocate based on nr_cpu_ids */
 	kstat_irqs_legacy = kzalloc_node(NR_IRQS_LEGACY * nr_cpu_ids *
 					  sizeof(int), GFP_NOWAIT, node);
@@ -175,29 +192,12 @@ int __init early_irq_init(void)
 		lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
 		alloc_desc_masks(&desc[i], node, true);
 		init_desc_masks(&desc[i]);
-		irq_desc_ptrs[i] = desc + i;
+		set_irq_desc(i, &desc[i]);
 	}
 
-	for (i = legacy_count; i < nr_irqs; i++)
-		irq_desc_ptrs[i] = NULL;
-
 	return arch_early_irq_init();
 }
 
-struct irq_desc *irq_to_desc(unsigned int irq)
-{
-	if (irq_desc_ptrs && irq < nr_irqs)
-		return irq_desc_ptrs[irq];
-
-	return NULL;
-}
-
-void replace_irq_desc(unsigned int irq, struct irq_desc *desc)
-{
-	if (irq_desc_ptrs && irq < nr_irqs)
-		irq_desc_ptrs[irq] = desc;
-}
-
 struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node)
 {
 	struct irq_desc *desc;
@@ -209,14 +209,14 @@ struct irq_desc * __ref irq_to_desc_allo
 		return NULL;
 	}
 
-	desc = irq_desc_ptrs[irq];
+	desc = irq_to_desc(irq);
 	if (desc)
 		return desc;
 
 	raw_spin_lock_irqsave(&sparse_irq_lock, flags);
 
 	/* We have to check it to avoid races with another CPU */
-	desc = irq_desc_ptrs[irq];
+	desc = irq_to_desc(irq);
 	if (desc)
 		goto out_unlock;
 
@@ -229,7 +229,7 @@ struct irq_desc * __ref irq_to_desc_allo
 	}
 	init_one_irq_desc(irq, desc, node);
 
-	irq_desc_ptrs[irq] = desc;
+	set_irq_desc(irq, desc);
 
 out_unlock:
 	raw_spin_unlock_irqrestore(&sparse_irq_lock, flags);

[PATCH 5/5] x86: remove arch_probe_nr_irqs

[Yinghai Lu]

so keep nr_irqs == NR_IRQS

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 arch/x86/kernel/apic/io_apic.c |   22 ----------------------
 1 file changed, 22 deletions(-)

Index: linux-2.6/arch/x86/kernel/apic/io_apic.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/apic/io_apic.c
+++ linux-2.6/arch/x86/kernel/apic/io_apic.c
@@ -3835,28 +3835,6 @@ void __init probe_nr_irqs_gsi(void)
 	printk(KERN_DEBUG "nr_irqs_gsi: %d\n", nr_irqs_gsi);
 }
 
-#ifdef CONFIG_SPARSE_IRQ
-int __init arch_probe_nr_irqs(void)
-{
-	int nr;
-
-	if (nr_irqs > (NR_VECTORS * nr_cpu_ids))
-		nr_irqs = NR_VECTORS * nr_cpu_ids;
-
-	nr = nr_irqs_gsi + 8 * nr_cpu_ids;
-#if defined(CONFIG_PCI_MSI) || defined(CONFIG_HT_IRQ)
-	/*
-	 * for MSI and HT dyn irq
-	 */
-	nr += nr_irqs_gsi * 64;
-#endif
-	if (nr < nr_irqs)
-		nr_irqs = nr;
-
-	return 0;
-}
-#endif
-
 static int __io_apic_set_pci_routing(struct device *dev, int irq,
 				struct io_apic_irq_attr *irq_attr)
 {

[PATCH 2/5] radix: move radix init early

[Yinghai Lu]

prepare to use it in early_irq_init()

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 init/main.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6/init/main.c
===================================================================
--- linux-2.6.orig/init/main.c
+++ linux-2.6/init/main.c
@@ -584,6 +584,7 @@ asmlinkage void __init start_kernel(void
 		local_irq_disable();
 	}
 	rcu_init();
+	radix_tree_init();
 	/* init some links before init_ISA_irqs() */
 	early_irq_init();
 	init_IRQ();
@@ -659,7 +660,6 @@ asmlinkage void __init start_kernel(void
 	key_init();
 	security_init();
 	vfs_caches_init(totalram_pages);
-	radix_tree_init();
 	signals_init();
 	/* rootfs populating might need page-writeback */
 	page_writeback_init();