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

2019-08-23 Thread Alex Williamson
On Thu,  8 Aug 2019 09:12:54 -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 
> Signed-off-by: Parav Pandit 
> ---
>  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, _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(_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(_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(_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 

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

2019-08-13 Thread Christoph Hellwig
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 
> Signed-off-by: Parav Pandit 

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

Reviewed-by: Christoph Hellwig 


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

2019-08-08 Thread Parav Pandit
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 
Signed-off-by: Parav Pandit 
---
 samples/vfio-mdev/mtty.c | 39 ---
 1 file changed, 8 insertions(+), 31 deletions(-)

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, _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(_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(_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(_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))
-- 
2.21.0.777.g83232e3864