diff mbox series

[v2,1/2] vfio-mdev/mtty: Simplify interrupt generation

Message ID 20190808141255.45236-2-parav@mellanox.com (mailing list archive)
State New, archived
Headers show
Series Simplify mtty driver and mdev core | expand

Commit Message

Parav Pandit Aug. 8, 2019, 2:12 p.m. UTC
While generating interrupt, mdev_state is already available for which
interrupt is generated.
Instead of doing indirect way from state->device->uuid-> to searching
state linearly in linked list on every interrupt generation,
directly use the available state.

Hence, simplify the code to use mdev_state and remove unused helper
function with that.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
---
 samples/vfio-mdev/mtty.c | 39 ++++++++-------------------------------
 1 file changed, 8 insertions(+), 31 deletions(-)

Comments

Christoph Hellwig Aug. 13, 2019, 4:39 p.m. UTC | #1
On Thu, Aug 08, 2019 at 09:12:54AM -0500, Parav Pandit wrote:
> While generating interrupt, mdev_state is already available for which
> interrupt is generated.
> Instead of doing indirect way from state->device->uuid-> to searching
> state linearly in linked list on every interrupt generation,
> directly use the available state.
> 
> Hence, simplify the code to use mdev_state and remove unused helper
> function with that.
> 
> Reviewed-by: Cornelia Huck <cohuck@redhat.com>
> Signed-off-by: Parav Pandit <parav@mellanox.com>

Looks good, the old code is rather backwards and a bad example to
copy:

Reviewed-by: Christoph Hellwig <hch@lst.de>
Alex Williamson Aug. 23, 2019, 8:48 p.m. UTC | #2
On Thu,  8 Aug 2019 09:12:54 -0500
Parav Pandit <parav@mellanox.com> wrote:

> While generating interrupt, mdev_state is already available for which
> interrupt is generated.
> Instead of doing indirect way from state->device->uuid-> to searching
> state linearly in linked list on every interrupt generation,
> directly use the available state.
> 
> Hence, simplify the code to use mdev_state and remove unused helper
> function with that.
> 
> Reviewed-by: Cornelia Huck <cohuck@redhat.com>
> Signed-off-by: Parav Pandit <parav@mellanox.com>
> ---
>  samples/vfio-mdev/mtty.c | 39 ++++++++-------------------------------
>  1 file changed, 8 insertions(+), 31 deletions(-)

Applied this commit to vfio next branch with Christoph's review for
v5.4.  As Connie has another use case for the mdev_uuid() API in
flight, I'm not applying patch 2/.  Thanks,

Alex

> diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
> index 92e770a06ea2..ce84a300a4da 100644
> --- a/samples/vfio-mdev/mtty.c
> +++ b/samples/vfio-mdev/mtty.c
> @@ -152,20 +152,9 @@ static const struct file_operations vd_fops = {
>  
>  /* function prototypes */
>  
> -static int mtty_trigger_interrupt(const guid_t *uuid);
> +static int mtty_trigger_interrupt(struct mdev_state *mdev_state);
>  
>  /* Helper functions */
> -static struct mdev_state *find_mdev_state_by_uuid(const guid_t *uuid)
> -{
> -	struct mdev_state *mds;
> -
> -	list_for_each_entry(mds, &mdev_devices_list, next) {
> -		if (guid_equal(mdev_uuid(mds->mdev), uuid))
> -			return mds;
> -	}
> -
> -	return NULL;
> -}
>  
>  static void dump_buffer(u8 *buf, uint32_t count)
>  {
> @@ -337,8 +326,7 @@ static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
>  				pr_err("Serial port %d: Fifo level trigger\n",
>  					index);
>  #endif
> -				mtty_trigger_interrupt(
> -						mdev_uuid(mdev_state->mdev));
> +				mtty_trigger_interrupt(mdev_state);
>  			}
>  		} else {
>  #if defined(DEBUG_INTR)
> @@ -352,8 +340,7 @@ static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
>  			 */
>  			if (mdev_state->s[index].uart_reg[UART_IER] &
>  								UART_IER_RLSI)
> -				mtty_trigger_interrupt(
> -						mdev_uuid(mdev_state->mdev));
> +				mtty_trigger_interrupt(mdev_state);
>  		}
>  		mutex_unlock(&mdev_state->rxtx_lock);
>  		break;
> @@ -372,8 +359,7 @@ static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
>  				pr_err("Serial port %d: IER_THRI write\n",
>  					index);
>  #endif
> -				mtty_trigger_interrupt(
> -						mdev_uuid(mdev_state->mdev));
> +				mtty_trigger_interrupt(mdev_state);
>  			}
>  
>  			mutex_unlock(&mdev_state->rxtx_lock);
> @@ -444,7 +430,7 @@ static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
>  #if defined(DEBUG_INTR)
>  			pr_err("Serial port %d: MCR_OUT2 write\n", index);
>  #endif
> -			mtty_trigger_interrupt(mdev_uuid(mdev_state->mdev));
> +			mtty_trigger_interrupt(mdev_state);
>  		}
>  
>  		if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
> @@ -452,7 +438,7 @@ static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
>  #if defined(DEBUG_INTR)
>  			pr_err("Serial port %d: MCR RTS/DTR write\n", index);
>  #endif
> -			mtty_trigger_interrupt(mdev_uuid(mdev_state->mdev));
> +			mtty_trigger_interrupt(mdev_state);
>  		}
>  		break;
>  
> @@ -503,8 +489,7 @@ static void handle_bar_read(unsigned int index, struct mdev_state *mdev_state,
>  #endif
>  			if (mdev_state->s[index].uart_reg[UART_IER] &
>  							 UART_IER_THRI)
> -				mtty_trigger_interrupt(
> -					mdev_uuid(mdev_state->mdev));
> +				mtty_trigger_interrupt(mdev_state);
>  		}
>  		mutex_unlock(&mdev_state->rxtx_lock);
>  
> @@ -1028,17 +1013,9 @@ static int mtty_set_irqs(struct mdev_device *mdev, uint32_t flags,
>  	return ret;
>  }
>  
> -static int mtty_trigger_interrupt(const guid_t *uuid)
> +static int mtty_trigger_interrupt(struct mdev_state *mdev_state)
>  {
>  	int ret = -1;
> -	struct mdev_state *mdev_state;
> -
> -	mdev_state = find_mdev_state_by_uuid(uuid);
> -
> -	if (!mdev_state) {
> -		pr_info("%s: mdev not found\n", __func__);
> -		return -EINVAL;
> -	}
>  
>  	if ((mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX) &&
>  	    (!mdev_state->msi_evtfd))
diff mbox series

Patch

diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index 92e770a06ea2..ce84a300a4da 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -152,20 +152,9 @@  static const struct file_operations vd_fops = {
 
 /* function prototypes */
 
-static int mtty_trigger_interrupt(const guid_t *uuid);
+static int mtty_trigger_interrupt(struct mdev_state *mdev_state);
 
 /* Helper functions */
-static struct mdev_state *find_mdev_state_by_uuid(const guid_t *uuid)
-{
-	struct mdev_state *mds;
-
-	list_for_each_entry(mds, &mdev_devices_list, next) {
-		if (guid_equal(mdev_uuid(mds->mdev), uuid))
-			return mds;
-	}
-
-	return NULL;
-}
 
 static void dump_buffer(u8 *buf, uint32_t count)
 {
@@ -337,8 +326,7 @@  static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
 				pr_err("Serial port %d: Fifo level trigger\n",
 					index);
 #endif
-				mtty_trigger_interrupt(
-						mdev_uuid(mdev_state->mdev));
+				mtty_trigger_interrupt(mdev_state);
 			}
 		} else {
 #if defined(DEBUG_INTR)
@@ -352,8 +340,7 @@  static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
 			 */
 			if (mdev_state->s[index].uart_reg[UART_IER] &
 								UART_IER_RLSI)
-				mtty_trigger_interrupt(
-						mdev_uuid(mdev_state->mdev));
+				mtty_trigger_interrupt(mdev_state);
 		}
 		mutex_unlock(&mdev_state->rxtx_lock);
 		break;
@@ -372,8 +359,7 @@  static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
 				pr_err("Serial port %d: IER_THRI write\n",
 					index);
 #endif
-				mtty_trigger_interrupt(
-						mdev_uuid(mdev_state->mdev));
+				mtty_trigger_interrupt(mdev_state);
 			}
 
 			mutex_unlock(&mdev_state->rxtx_lock);
@@ -444,7 +430,7 @@  static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
 #if defined(DEBUG_INTR)
 			pr_err("Serial port %d: MCR_OUT2 write\n", index);
 #endif
-			mtty_trigger_interrupt(mdev_uuid(mdev_state->mdev));
+			mtty_trigger_interrupt(mdev_state);
 		}
 
 		if ((mdev_state->s[index].uart_reg[UART_IER] & UART_IER_MSI) &&
@@ -452,7 +438,7 @@  static void handle_bar_write(unsigned int index, struct mdev_state *mdev_state,
 #if defined(DEBUG_INTR)
 			pr_err("Serial port %d: MCR RTS/DTR write\n", index);
 #endif
-			mtty_trigger_interrupt(mdev_uuid(mdev_state->mdev));
+			mtty_trigger_interrupt(mdev_state);
 		}
 		break;
 
@@ -503,8 +489,7 @@  static void handle_bar_read(unsigned int index, struct mdev_state *mdev_state,
 #endif
 			if (mdev_state->s[index].uart_reg[UART_IER] &
 							 UART_IER_THRI)
-				mtty_trigger_interrupt(
-					mdev_uuid(mdev_state->mdev));
+				mtty_trigger_interrupt(mdev_state);
 		}
 		mutex_unlock(&mdev_state->rxtx_lock);
 
@@ -1028,17 +1013,9 @@  static int mtty_set_irqs(struct mdev_device *mdev, uint32_t flags,
 	return ret;
 }
 
-static int mtty_trigger_interrupt(const guid_t *uuid)
+static int mtty_trigger_interrupt(struct mdev_state *mdev_state)
 {
 	int ret = -1;
-	struct mdev_state *mdev_state;
-
-	mdev_state = find_mdev_state_by_uuid(uuid);
-
-	if (!mdev_state) {
-		pr_info("%s: mdev not found\n", __func__);
-		return -EINVAL;
-	}
 
 	if ((mdev_state->irq_index == VFIO_PCI_MSI_IRQ_INDEX) &&
 	    (!mdev_state->msi_evtfd))