[PATCH v2 11/26] genirq: Split __irq_reserve_irqs from irq_alloc_descs

Yinghai Lu
2013-02-08T19:28:53Z

irq_alloc_descs and irq_reserve_irqs are almost the same.
Separate code out to __irq_reserved_irqs, and other two reuse
__irq_reserve_irqs.

And will use __irq_reserve_irqs for coming ioapic hotplug support.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
include/linux/irq.h | 1 +
kernel/irq/irqdesc.c | 54 +++++++++++++++++++++++++++++---------------------
2 files changed, 32 insertions(+), 23 deletions(-)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index bc4e066..4e0fcbb 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -600,6 +600,7 @@ int __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,

void irq_free_descs(unsigned int irq, unsigned int cnt);
int irq_reserve_irqs(unsigned int from, unsigned int cnt);
+int __irq_reserve_irqs(int irq, unsigned int from, unsigned int cnt);

static inline void irq_free_desc(unsigned int irq)
{
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 192a302..3b9fb92 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -340,18 +340,15 @@ void irq_free_descs(unsigned int from, unsigned int cnt)
EXPORT_SYMBOL_GPL(irq_free_descs);

/**
- * irq_alloc_descs - allocate and initialize a range of irq descriptors
- * @irq: Allocate for specific irq number if irq >= 0
+ * __irq_reserve_descs - reserve and initialize a range of irq descriptors
+ * @irq: Reserve for specific irq number if irq >= 0
* @from: Start the search from this irq number
- * @cnt: Number of consecutive irqs to allocate.
- * @node: Preferred node on which the irq descriptor should be allocated
- * @owner: Owning module (can be NULL)
+ * @cnt: Number of consecutive irqs to reserve.
*
* Returns the first irq number or error code
*/
int __ref
-__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
- struct module *owner)
+__irq_reserve_irqs(int irq, unsigned int from, unsigned int cnt)
{
int start, ret;

@@ -369,7 +366,7 @@ __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
from, cnt, 0);
ret = -EEXIST;
- if (irq >=0 && start != irq)
+ if (irq >= 0 && start != irq)
goto err;

if (start + cnt > nr_irqs) {
@@ -380,12 +377,36 @@ __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,

bitmap_set(allocated_irqs, start, cnt);
mutex_unlock(&sparse_irq_lock);
- return alloc_descs(start, cnt, node, owner);
+ return start;

err:
mutex_unlock(&sparse_irq_lock);
return ret;
}
+
+/**
+ * irq_alloc_descs - allocate and initialize a range of irq descriptors
+ * @irq: Allocate for specific irq number if irq >= 0
+ * @from: Start the search from this irq number
+ * @cnt: Number of consecutive irqs to allocate.
+ * @node: Preferred node on which the irq descriptor should be allocated
+ * @owner: Owning module (can be NULL)
+ *
+ * Returns the first irq number or error code
+ */
+int __ref
+__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
+ struct module *owner)
+{
+ int start;
+
+ start = __irq_reserve_irqs(irq, from, cnt);
+
+ if (start < 0)
+ return start;
+
+ return alloc_descs(start, cnt, node, owner);
+}
EXPORT_SYMBOL_GPL(__irq_alloc_descs);

/**
@@ -397,20 +418,7 @@ EXPORT_SYMBOL_GPL(__irq_alloc_descs);
*/
int irq_reserve_irqs(unsigned int from, unsigned int cnt)
{
- unsigned int start;
- int ret = 0;
-
- if (!cnt || (from + cnt) > nr_irqs)
- return -EINVAL;
-
- mutex_lock(&sparse_irq_lock);
- start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
- if (start == from)
- bitmap_set(allocated_irqs, start, cnt);
- else
- ret = -EEXIST;
- mutex_unlock(&sparse_irq_lock);
- return ret;
+ return __irq_reserve_irqs(from, from, cnt);
}

/**
--
1.7.10.4