[PATCH char-misc-next v3 4/8] misc: mic: add threaded irq support in host driver
From: Sudeep Dutt
Date: Fri Jul 11 2014 - 17:07:40 EST
From: Siva Yerramreddy <yshivakrishna@xxxxxxxxx>
Convert mic_request_irq to mic_request_threaded_irq to support threaded
irq for virtual devices on mic bus.
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx>
Reviewed-by: Nikhil Rao <nikhil.rao@xxxxxxxxx>
Reviewed-by: Sudeep Dutt <sudeep.dutt@xxxxxxxxx>
Signed-off-by: Siva Yerramreddy <yshivakrishna@xxxxxxxxx>
---
drivers/misc/mic/host/mic_intr.c | 121 ++++++++++++++++++++++---------------
drivers/misc/mic/host/mic_intr.h | 24 +++++---
drivers/misc/mic/host/mic_main.c | 5 +-
drivers/misc/mic/host/mic_virtio.c | 6 +-
4 files changed, 96 insertions(+), 60 deletions(-)
diff --git a/drivers/misc/mic/host/mic_intr.c b/drivers/misc/mic/host/mic_intr.c
index dbc5afd..d686f28 100644
--- a/drivers/misc/mic/host/mic_intr.c
+++ b/drivers/misc/mic/host/mic_intr.c
@@ -24,28 +24,29 @@
#include "../common/mic_dev.h"
#include "mic_device.h"
-/*
- * mic_invoke_callback - Invoke callback functions registered for
- * the corresponding source id.
- *
- * @mdev: pointer to the mic_device instance
- * @idx: The interrupt source id.
- *
- * Returns none.
- */
-static inline void mic_invoke_callback(struct mic_device *mdev, int idx)
+static irqreturn_t mic_thread_fn(int irq, void *dev)
{
+ struct mic_device *mdev = dev;
+ struct mic_intr_info *intr_info = mdev->intr_info;
+ struct mic_irq_info *irq_info = &mdev->irq_info;
struct mic_intr_cb *intr_cb;
struct pci_dev *pdev = container_of(mdev->sdev->parent,
- struct pci_dev, dev);
+ struct pci_dev, dev);
+ int i;
- spin_lock(&mdev->irq_info.mic_intr_lock);
- list_for_each_entry(intr_cb, &mdev->irq_info.cb_list[idx], list)
- if (intr_cb->func)
- intr_cb->func(pdev->irq, intr_cb->data);
- spin_unlock(&mdev->irq_info.mic_intr_lock);
+ spin_lock(&irq_info->mic_thread_lock);
+ for (i = intr_info->intr_start_idx[MIC_INTR_DB];
+ i < intr_info->intr_len[MIC_INTR_DB]; i++)
+ if (test_and_clear_bit(i, &irq_info->mask)) {
+ list_for_each_entry(intr_cb, &irq_info->cb_list[i],
+ list)
+ if (intr_cb->thread_fn)
+ intr_cb->thread_fn(pdev->irq,
+ intr_cb->data);
+ }
+ spin_unlock(&irq_info->mic_thread_lock);
+ return IRQ_HANDLED;
}
-
/**
* mic_interrupt - Generic interrupt handler for
* MSI and INTx based interrupts.
@@ -53,7 +54,11 @@ static inline void mic_invoke_callback(struct mic_device *mdev, int idx)
static irqreturn_t mic_interrupt(int irq, void *dev)
{
struct mic_device *mdev = dev;
- struct mic_intr_info *info = mdev->intr_info;
+ struct mic_intr_info *intr_info = mdev->intr_info;
+ struct mic_irq_info *irq_info = &mdev->irq_info;
+ struct mic_intr_cb *intr_cb;
+ struct pci_dev *pdev = container_of(mdev->sdev->parent,
+ struct pci_dev, dev);
u32 mask;
int i;
@@ -61,12 +66,19 @@ static irqreturn_t mic_interrupt(int irq, void *dev)
if (!mask)
return IRQ_NONE;
- for (i = info->intr_start_idx[MIC_INTR_DB];
- i < info->intr_len[MIC_INTR_DB]; i++)
- if (mask & BIT(i))
- mic_invoke_callback(mdev, i);
-
- return IRQ_HANDLED;
+ spin_lock(&irq_info->mic_intr_lock);
+ for (i = intr_info->intr_start_idx[MIC_INTR_DB];
+ i < intr_info->intr_len[MIC_INTR_DB]; i++)
+ if (mask & BIT(i)) {
+ list_for_each_entry(intr_cb, &irq_info->cb_list[i],
+ list)
+ if (intr_cb->handler)
+ intr_cb->handler(pdev->irq,
+ intr_cb->data);
+ set_bit(i, &irq_info->mask);
+ }
+ spin_unlock(&irq_info->mic_intr_lock);
+ return IRQ_WAKE_THREAD;
}
/* Return the interrupt offset from the index. Index is 0 based. */
@@ -99,14 +111,15 @@ static struct msix_entry *mic_get_available_vector(struct mic_device *mdev)
*
* @mdev: pointer to the mic_device instance
* @idx: The source id to be registered.
- * @func: The function to be called when the source id receives
+ * @handler: The function to be called when the source id receives
* the interrupt.
+ * @thread_fn: thread fn. corresponding to the handler
* @data: Private data of the requester.
* Return the callback structure that was registered or an
* appropriate error on failure.
*/
static struct mic_intr_cb *mic_register_intr_callback(struct mic_device *mdev,
- u8 idx, irqreturn_t (*func) (int irq, void *dev),
+ u8 idx, irq_handler_t handler, irq_handler_t thread_fn,
void *data)
{
struct mic_intr_cb *intr_cb;
@@ -117,7 +130,8 @@ static struct mic_intr_cb *mic_register_intr_callback(struct mic_device *mdev,
if (!intr_cb)
return ERR_PTR(-ENOMEM);
- intr_cb->func = func;
+ intr_cb->handler = handler;
+ intr_cb->thread_fn = thread_fn;
intr_cb->data = data;
intr_cb->cb_id = ida_simple_get(&mdev->irq_info.cb_ida,
0, 0, GFP_KERNEL);
@@ -126,9 +140,11 @@ static struct mic_intr_cb *mic_register_intr_callback(struct mic_device *mdev,
goto ida_fail;
}
+ spin_lock(&mdev->irq_info.mic_thread_lock);
spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
list_add_tail(&intr_cb->list, &mdev->irq_info.cb_list[idx]);
spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
+ spin_unlock(&mdev->irq_info.mic_thread_lock);
return intr_cb;
ida_fail:
@@ -152,8 +168,9 @@ static u8 mic_unregister_intr_callback(struct mic_device *mdev, u32 idx)
unsigned long flags;
int i;
+ spin_lock(&mdev->irq_info.mic_thread_lock);
+ spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
for (i = 0; i < MIC_NUM_OFFSETS; i++) {
- spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
list_for_each_safe(pos, tmp, &mdev->irq_info.cb_list[i]) {
intr_cb = list_entry(pos, struct mic_intr_cb, list);
if (intr_cb->cb_id == idx) {
@@ -163,11 +180,13 @@ static u8 mic_unregister_intr_callback(struct mic_device *mdev, u32 idx)
kfree(intr_cb);
spin_unlock_irqrestore(
&mdev->irq_info.mic_intr_lock, flags);
+ spin_unlock(&mdev->irq_info.mic_thread_lock);
return i;
}
}
- spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
}
+ spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
+ spin_unlock(&mdev->irq_info.mic_thread_lock);
return MIC_NUM_OFFSETS;
}
@@ -242,6 +261,7 @@ static int mic_setup_callbacks(struct mic_device *mdev)
INIT_LIST_HEAD(&mdev->irq_info.cb_list[i]);
ida_init(&mdev->irq_info.cb_ida);
spin_lock_init(&mdev->irq_info.mic_intr_lock);
+ spin_lock_init(&mdev->irq_info.mic_thread_lock);
return 0;
}
@@ -258,14 +278,12 @@ static void mic_release_callbacks(struct mic_device *mdev)
struct mic_intr_cb *intr_cb;
int i;
+ spin_lock(&mdev->irq_info.mic_thread_lock);
+ spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
for (i = 0; i < MIC_NUM_OFFSETS; i++) {
- spin_lock_irqsave(&mdev->irq_info.mic_intr_lock, flags);
- if (list_empty(&mdev->irq_info.cb_list[i])) {
- spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock,
- flags);
+ if (list_empty(&mdev->irq_info.cb_list[i]))
break;
- }
list_for_each_safe(pos, tmp, &mdev->irq_info.cb_list[i]) {
intr_cb = list_entry(pos, struct mic_intr_cb, list);
@@ -274,8 +292,9 @@ static void mic_release_callbacks(struct mic_device *mdev)
intr_cb->cb_id);
kfree(intr_cb);
}
- spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
}
+ spin_unlock_irqrestore(&mdev->irq_info.mic_intr_lock, flags);
+ spin_unlock(&mdev->irq_info.mic_thread_lock);
ida_destroy(&mdev->irq_info.cb_ida);
kfree(mdev->irq_info.cb_list);
}
@@ -313,7 +332,8 @@ static int mic_setup_msi(struct mic_device *mdev, struct pci_dev *pdev)
goto err_nomem2;
}
- rc = request_irq(pdev->irq, mic_interrupt, 0 , "mic-msi", mdev);
+ rc = request_threaded_irq(pdev->irq, mic_interrupt, mic_thread_fn,
+ 0, "mic-msi", mdev);
if (rc) {
dev_err(&pdev->dev, "Error allocating MSI interrupt\n");
goto err_irq_req_fail;
@@ -353,8 +373,8 @@ static int mic_setup_intx(struct mic_device *mdev, struct pci_dev *pdev)
goto err_nomem;
}
- rc = request_irq(pdev->irq, mic_interrupt,
- IRQF_SHARED, "mic-intx", mdev);
+ rc = request_threaded_irq(pdev->irq, mic_interrupt, mic_thread_fn,
+ IRQF_SHARED, "mic-intx", mdev);
if (rc)
goto err;
@@ -391,13 +411,14 @@ int mic_next_db(struct mic_device *mdev)
#define MK_COOKIE(x, y) ((x) | (y) << COOKIE_ID_SHIFT)
/**
- * mic_request_irq - request an irq. mic_mutex needs
+ * mic_request_threaded_irq - request an irq. mic_mutex needs
* to be held before calling this function.
*
* @mdev: pointer to mic_device instance
- * @func: The callback function that handles the interrupt.
+ * @handler: The callback function that handles the interrupt.
* The function needs to call ack_interrupts
* (mdev->ops->ack_interrupt(mdev)) when handling the interrupts.
+ * @thread_fn: thread fn required by request_threaded_irq.
* @name: The ASCII name of the callee requesting the irq.
* @data: private data that is returned back when calling the
* function handler.
@@ -412,10 +433,11 @@ int mic_next_db(struct mic_device *mdev)
* error code.
*
*/
-struct mic_irq *mic_request_irq(struct mic_device *mdev,
- irqreturn_t (*func)(int irq, void *dev),
- const char *name, void *data, int intr_src,
- enum mic_intr_type type)
+struct mic_irq *
+mic_request_threaded_irq(struct mic_device *mdev,
+ irq_handler_t handler, irq_handler_t thread_fn,
+ const char *name, void *data, int intr_src,
+ enum mic_intr_type type)
{
u16 offset;
int rc = 0;
@@ -444,7 +466,8 @@ struct mic_irq *mic_request_irq(struct mic_device *mdev,
goto err;
}
- rc = request_irq(msix->vector, func, 0, name, data);
+ rc = request_threaded_irq(msix->vector, handler, thread_fn,
+ 0, name, data);
if (rc) {
dev_dbg(mdev->sdev->parent,
"request irq failed rc = %d\n", rc);
@@ -458,8 +481,8 @@ struct mic_irq *mic_request_irq(struct mic_device *mdev,
dev_dbg(mdev->sdev->parent, "irq: %d assigned for src: %d\n",
msix->vector, intr_src);
} else {
- intr_cb = mic_register_intr_callback(mdev,
- offset, func, data);
+ intr_cb = mic_register_intr_callback(mdev, offset, handler,
+ thread_fn, data);
if (IS_ERR(intr_cb)) {
dev_err(mdev->sdev->parent,
"No available callback entries for use\n");
@@ -487,9 +510,9 @@ err:
* needs to be held before calling this function.
*
* @mdev: pointer to mic_device instance
- * @cookie: cookie obtained during a successful call to mic_request_irq
+ * @cookie: cookie obtained during a successful call to mic_request_threaded_irq
* @data: private data specified by the calling function during the
- * mic_request_irq
+ * mic_request_threaded_irq
*
* returns: none.
*/
diff --git a/drivers/misc/mic/host/mic_intr.h b/drivers/misc/mic/host/mic_intr.h
index 6091aa9..b1334dd 100644
--- a/drivers/misc/mic/host/mic_intr.h
+++ b/drivers/misc/mic/host/mic_intr.h
@@ -21,6 +21,8 @@
#ifndef _MIC_INTR_H_
#define _MIC_INTR_H_
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
/*
* The minimum number of msix vectors required for normal operation.
* 3 for virtio network, console and block devices.
@@ -68,7 +70,11 @@ struct mic_intr_info {
* @num_vectors: The number of MSI/MSI-x vectors that have been allocated.
* @cb_ida: callback ID allocator to track the callbacks registered.
* @mic_intr_lock: spinlock to protect the interrupt callback list.
+ * @mic_thread_lock: spinlock to protect the thread callback list.
+ * This lock is used to protect against thread_fn while
+ * mic_intr_lock is used to protect against interrupt handler.
* @cb_list: Array of callback lists one for each source.
+ * @mask: Mask used by the main thread fn to call the underlying thread fns.
*/
struct mic_irq_info {
int next_avail_src;
@@ -77,19 +83,23 @@ struct mic_irq_info {
u16 num_vectors;
struct ida cb_ida;
spinlock_t mic_intr_lock;
+ spinlock_t mic_thread_lock;
struct list_head *cb_list;
+ unsigned long mask;
};
/**
* struct mic_intr_cb - Interrupt callback structure.
*
- * @func: The callback function
+ * @handler: The callback function
+ * @thread_fn: The thread_fn.
* @data: Private data of the requester.
* @cb_id: The callback id. Identifies this callback.
* @list: list head pointing to the next callback structure.
*/
struct mic_intr_cb {
- irqreturn_t (*func) (int irq, void *data);
+ irq_handler_t handler;
+ irq_handler_t thread_fn;
void *data;
int cb_id;
struct list_head list;
@@ -124,11 +134,11 @@ struct mic_hw_intr_ops {
};
int mic_next_db(struct mic_device *mdev);
-struct mic_irq *mic_request_irq(struct mic_device *mdev,
- irqreturn_t (*func)(int irq, void *data),
- const char *name, void *data, int intr_src,
- enum mic_intr_type type);
-
+struct mic_irq *
+mic_request_threaded_irq(struct mic_device *mdev,
+ irq_handler_t handler, irq_handler_t thread_fn,
+ const char *name, void *data, int intr_src,
+ enum mic_intr_type type);
void mic_free_irq(struct mic_device *mdev,
struct mic_irq *cookie, void *data);
int mic_setup_interrupts(struct mic_device *mdev, struct pci_dev *pdev);
diff --git a/drivers/misc/mic/host/mic_main.c b/drivers/misc/mic/host/mic_main.c
index c04a021..fdc9c13 100644
--- a/drivers/misc/mic/host/mic_main.c
+++ b/drivers/misc/mic/host/mic_main.c
@@ -389,8 +389,9 @@ static int mic_probe(struct pci_dev *pdev,
mutex_lock(&mdev->mic_mutex);
mdev->shutdown_db = mic_next_db(mdev);
- mdev->shutdown_cookie = mic_request_irq(mdev, mic_shutdown_db,
- "shutdown-interrupt", mdev, mdev->shutdown_db, MIC_INTR_DB);
+ mdev->shutdown_cookie = mic_request_threaded_irq(mdev, mic_shutdown_db,
+ NULL, "shutdown-interrupt", mdev,
+ mdev->shutdown_db, MIC_INTR_DB);
if (IS_ERR(mdev->shutdown_cookie)) {
rc = PTR_ERR(mdev->shutdown_cookie);
mutex_unlock(&mdev->mic_mutex);
diff --git a/drivers/misc/mic/host/mic_virtio.c b/drivers/misc/mic/host/mic_virtio.c
index 7e1ef0e..aba3e83 100644
--- a/drivers/misc/mic/host/mic_virtio.c
+++ b/drivers/misc/mic/host/mic_virtio.c
@@ -594,8 +594,10 @@ int mic_virtio_add_device(struct mic_vdev *mvdev,
snprintf(irqname, sizeof(irqname), "mic%dvirtio%d", mdev->id,
mvdev->virtio_id);
mvdev->virtio_db = mic_next_db(mdev);
- mvdev->virtio_cookie = mic_request_irq(mdev, mic_virtio_intr_handler,
- irqname, mvdev, mvdev->virtio_db, MIC_INTR_DB);
+ mvdev->virtio_cookie = mic_request_threaded_irq(mdev,
+ mic_virtio_intr_handler,
+ NULL, irqname, mvdev,
+ mvdev->virtio_db, MIC_INTR_DB);
if (IS_ERR(mvdev->virtio_cookie)) {
ret = PTR_ERR(mvdev->virtio_cookie);
dev_dbg(mdev->sdev->parent, "request irq failed\n");
--
1.8.2.1
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