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Feng Liu

2023-Mar-15 18:54 UTC

[PATCH v2 2/3] virtio_ring: Avoid using inline for small functions

Remove the inline keyword, according to kernel coding style [1], defining
inline functions is not necessary for samll functions.

It is verified with GCC 12.2.0, the generated code with/without inline
is the same. Additionally tested with kernel pktgen and iperf, and
verified the result, pps of the results are the same in the cases of
with/without inline.

[1]
https://www.kernel.org/doc/html/v6.2-rc3/process/coding-style.html#the-inline-disease

Signed-off-by: Feng Liu <feliu at nvidia.com>
Reviewed-by: Jiri Pirko <jiri at nvidia.com>
---
 drivers/virtio/virtio_ring.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 41144b5246a8..a26fab91c59f 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -233,8 +233,8 @@ static void vring_free(struct virtqueue *_vq);
 
 #define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq)
 
-static inline bool virtqueue_use_indirect(struct vring_virtqueue *vq,
-					  unsigned int total_sg)
+static bool virtqueue_use_indirect(struct vring_virtqueue *vq,
+				   unsigned int total_sg)
 {
 	/*
 	 * If the host supports indirect descriptor tables, and we have multiple
@@ -349,7 +349,7 @@ static void vring_free_queue(struct virtio_device *vdev,
size_t size,
  * making all of the arch DMA ops work on the vring device itself
  * is a mess.
  */
-static inline struct device *vring_dma_dev(const struct vring_virtqueue *vq)
+static struct device *vring_dma_dev(const struct vring_virtqueue *vq)
 {
 	return vq->dma_dev;
 }
@@ -784,7 +784,7 @@ static void detach_buf_split(struct vring_virtqueue *vq,
unsigned int head,
 	}
 }
 
-static inline bool more_used_split(const struct vring_virtqueue *vq)
+static bool more_used_split(const struct vring_virtqueue *vq)
 {
 	return vq->last_used_idx != virtio16_to_cpu(vq->vq.vdev,
 			vq->split.vring.used->idx);
@@ -1172,12 +1172,12 @@ static int virtqueue_resize_split(struct virtqueue *_vq,
u32 num)
 /*
  * Packed ring specific functions - *_packed().
  */
-static inline bool packed_used_wrap_counter(u16 last_used_idx)
+static bool packed_used_wrap_counter(u16 last_used_idx)
 {
 	return !!(last_used_idx & (1 << VRING_PACKED_EVENT_F_WRAP_CTR));
 }
 
-static inline u16 packed_last_used(u16 last_used_idx)
+static u16 packed_last_used(u16 last_used_idx)
 {
 	return last_used_idx & ~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR));
 }
@@ -1612,7 +1612,7 @@ static inline bool is_used_desc_packed(const struct
vring_virtqueue *vq,
 	return avail == used && used == used_wrap_counter;
 }
 
-static inline bool more_used_packed(const struct vring_virtqueue *vq)
+static bool more_used_packed(const struct vring_virtqueue *vq)
 {
 	u16 last_used;
 	u16 last_used_idx;
-- 
2.34.1

Jason Wang

2023-Mar-17 03:16 UTC

head link

[PATCH v2 2/3] virtio_ring: Avoid using inline for small functions

On Thu, Mar 16, 2023 at 2:55?AM Feng Liu <feliu at nvidia.com>
wrote:>
> Remove the inline keyword, according to kernel coding style [1], defining
> inline functions is not necessary for samll functions.
>
> It is verified with GCC 12.2.0, the generated code with/without inline
> is the same. Additionally tested with kernel pktgen and iperf, and
> verified the result, pps of the results are the same in the cases of
> with/without inline.
>
> [1]
>
https://www.kernel.org/doc/html/v6.2-rc3/process/coding-style.html#the-inline-disease
>
> Signed-off-by: Feng Liu <feliu at nvidia.com>
> Reviewed-by: Jiri Pirko <jiri at nvidia.com>
Acked-by: Jason Wang <jasowang at redhat.com>

Thanks
> ---
>  drivers/virtio/virtio_ring.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 41144b5246a8..a26fab91c59f 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -233,8 +233,8 @@ static void vring_free(struct virtqueue *_vq);
>
>  #define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq)
>
> -static inline bool virtqueue_use_indirect(struct vring_virtqueue *vq,
> -                                         unsigned int total_sg)
> +static bool virtqueue_use_indirect(struct vring_virtqueue *vq,
> +                                  unsigned int total_sg)
>  {
>         /*
>          * If the host supports indirect descriptor tables, and we have
multiple
> @@ -349,7 +349,7 @@ static void vring_free_queue(struct virtio_device
*vdev, size_t size,
>   * making all of the arch DMA ops work on the vring device itself
>   * is a mess.
>   */
> -static inline struct device *vring_dma_dev(const struct vring_virtqueue
*vq)
> +static struct device *vring_dma_dev(const struct vring_virtqueue *vq)
>  {
>         return vq->dma_dev;
>  }
> @@ -784,7 +784,7 @@ static void detach_buf_split(struct vring_virtqueue
*vq, unsigned int head,
>         }
>  }
>
> -static inline bool more_used_split(const struct vring_virtqueue *vq)
> +static bool more_used_split(const struct vring_virtqueue *vq)
>  {
>         return vq->last_used_idx != virtio16_to_cpu(vq->vq.vdev,
>                         vq->split.vring.used->idx);
> @@ -1172,12 +1172,12 @@ static int virtqueue_resize_split(struct virtqueue
*_vq, u32 num)
>  /*
>   * Packed ring specific functions - *_packed().
>   */
> -static inline bool packed_used_wrap_counter(u16 last_used_idx)
> +static bool packed_used_wrap_counter(u16 last_used_idx)
>  {
>         return !!(last_used_idx & (1 <<
VRING_PACKED_EVENT_F_WRAP_CTR));
>  }
>
> -static inline u16 packed_last_used(u16 last_used_idx)
> +static u16 packed_last_used(u16 last_used_idx)
>  {
>         return last_used_idx & ~(-(1 <<
VRING_PACKED_EVENT_F_WRAP_CTR));
>  }
> @@ -1612,7 +1612,7 @@ static inline bool is_used_desc_packed(const struct
vring_virtqueue *vq,
>         return avail == used && used == used_wrap_counter;
>  }
>
> -static inline bool more_used_packed(const struct vring_virtqueue *vq)
> +static bool more_used_packed(const struct vring_virtqueue *vq)
>  {
>         u16 last_used;
>         u16 last_used_idx;
> --
> 2.34.1
>

David Edmondson

2023-Mar-17 09:16 UTC

head link

[PATCH v2 2/3] virtio_ring: Avoid using inline for small functions

Feng Liu <feliu at nvidia.com> writes:
> Remove the inline keyword, according to kernel coding style [1], defining
> inline functions is not necessary for samll functions.
>
> It is verified with GCC 12.2.0, the generated code with/without inline
> is the same. Additionally tested with kernel pktgen and iperf, and
> verified the result, pps of the results are the same in the cases of
> with/without inline.
>
> [1]
>
https://www.kernel.org/doc/html/v6.2-rc3/process/coding-style.html#the-inline-disease
>
> Signed-off-by: Feng Liu <feliu at nvidia.com>
> Reviewed-by: Jiri Pirko <jiri at nvidia.com>
Reviewed-by: David Edmondson <david.edmondson at oracle.com>
> ---
>  drivers/virtio/virtio_ring.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 41144b5246a8..a26fab91c59f 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -233,8 +233,8 @@ static void vring_free(struct virtqueue *_vq);
>  
>  #define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq)
>  
> -static inline bool virtqueue_use_indirect(struct vring_virtqueue *vq,
> -					  unsigned int total_sg)
> +static bool virtqueue_use_indirect(struct vring_virtqueue *vq,
> +				   unsigned int total_sg)
>  {
>  	/*
>  	 * If the host supports indirect descriptor tables, and we have multiple
> @@ -349,7 +349,7 @@ static void vring_free_queue(struct virtio_device
*vdev, size_t size,
>   * making all of the arch DMA ops work on the vring device itself
>   * is a mess.
>   */
> -static inline struct device *vring_dma_dev(const struct vring_virtqueue
*vq)
> +static struct device *vring_dma_dev(const struct vring_virtqueue *vq)
>  {
>  	return vq->dma_dev;
>  }
> @@ -784,7 +784,7 @@ static void detach_buf_split(struct vring_virtqueue
*vq, unsigned int head,
>  	}
>  }
>  
> -static inline bool more_used_split(const struct vring_virtqueue *vq)
> +static bool more_used_split(const struct vring_virtqueue *vq)
>  {
>  	return vq->last_used_idx != virtio16_to_cpu(vq->vq.vdev,
>  			vq->split.vring.used->idx);
> @@ -1172,12 +1172,12 @@ static int virtqueue_resize_split(struct virtqueue
*_vq, u32 num)
>  /*
>   * Packed ring specific functions - *_packed().
>   */
> -static inline bool packed_used_wrap_counter(u16 last_used_idx)
> +static bool packed_used_wrap_counter(u16 last_used_idx)
>  {
>  	return !!(last_used_idx & (1 <<
VRING_PACKED_EVENT_F_WRAP_CTR));
>  }
>  
> -static inline u16 packed_last_used(u16 last_used_idx)
> +static u16 packed_last_used(u16 last_used_idx)
>  {
>  	return last_used_idx & ~(-(1 <<
VRING_PACKED_EVENT_F_WRAP_CTR));
>  }
> @@ -1612,7 +1612,7 @@ static inline bool is_used_desc_packed(const struct
vring_virtqueue *vq,
>  	return avail == used && used == used_wrap_counter;
>  }
>  
> -static inline bool more_used_packed(const struct vring_virtqueue *vq)
> +static bool more_used_packed(const struct vring_virtqueue *vq)
>  {
>  	u16 last_used;
>  	u16 last_used_idx;
> -- 
> 2.34.1-- 
But are you safe Miss Gradenko?

Linux Virtualization - Mar 2023 - [PATCH v2 2/3] virtio_ring: Avoid using inline for small functions

[PATCH v2 2/3] virtio_ring: Avoid using inline for small functions

[PATCH v2 2/3] virtio_ring: Avoid using inline for small functions

[PATCH v2 2/3] virtio_ring: Avoid using inline for small functions