diff options
Diffstat (limited to 'src/vnet/devices/virtio/virtio_buffering.h')
| -rw-r--r-- | src/vnet/devices/virtio/virtio_buffering.h | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/src/vnet/devices/virtio/virtio_buffering.h b/src/vnet/devices/virtio/virtio_buffering.h new file mode 100644 index 00000000000..ef3d9d27652 --- /dev/null +++ b/src/vnet/devices/virtio/virtio_buffering.h @@ -0,0 +1,259 @@ +/* + *------------------------------------------------------------------ + * Copyright (c) 2020 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + *------------------------------------------------------------------ + */ + +#ifndef _VNET_DEVICES_VIRTIO_VIRTIO_BUFFERING_H_ +#define _VNET_DEVICES_VIRTIO_VIRTIO_BUFFERING_H_ + +#define VIRTIO_BUFFERING_DEFAULT_SIZE 1024 +#define VIRTIO_BUFFERING_TIMEOUT 1e-5 + +typedef struct +{ + f64 timeout_ts; + u32 *buffers; + u32 node_index; + u16 size; + u16 free_size; + u16 front; + u16 back; + u8 is_enable; +} virtio_vring_buffering_t; + +static_always_inline clib_error_t * +virtio_vring_buffering_init (virtio_vring_buffering_t ** buffering, + u32 node_index, u16 size) +{ + if (*buffering) + return clib_error_return (0, "buffering: already initialized"); + + if (!is_pow2 (size)) + return clib_error_return (0, "buffering: size must be power of 2"); + + if (size > 32768) + return clib_error_return (0, "buffering: size must be 32768 or lower"); + + if (size == 0) + size = VIRTIO_BUFFERING_DEFAULT_SIZE; + + virtio_vring_buffering_t *b_temp = 0; + b_temp = + (virtio_vring_buffering_t *) + clib_mem_alloc (sizeof (virtio_vring_buffering_t)); + if (!b_temp) + return clib_error_return (0, "buffering: memory allocation failed"); + + clib_memset (b_temp, 0, sizeof (virtio_vring_buffering_t)); + + b_temp->node_index = node_index; + b_temp->free_size = size; + b_temp->size = size; + + vec_validate_aligned (b_temp->buffers, size, CLIB_CACHE_LINE_BYTES); + b_temp->is_enable = 1; + + *buffering = b_temp; + return 0; +} + +static_always_inline void +virtio_vring_buffering_buffers_free (vlib_main_t * vm, + virtio_vring_buffering_t * buffering) +{ + u16 n_buffers = buffering->size - buffering->free_size; + if (n_buffers) + { + vlib_buffer_free_from_ring (vm, buffering->buffers, buffering->front, + buffering->size, n_buffers); + buffering->free_size += n_buffers; + } +} + +static_always_inline void +virtio_vring_buffering_free (vlib_main_t * vm, + virtio_vring_buffering_t * buffering) +{ + if (buffering) + { + virtio_vring_buffering_buffers_free (vm, buffering); + vec_free (buffering->buffers); + clib_mem_free (buffering); + } +} + +static_always_inline u8 +virtio_vring_buffering_is_enable (virtio_vring_buffering_t * buffering) +{ + if (buffering) + return buffering->is_enable; + + return 0; +} + +static_always_inline void +virtio_vring_buffering_set_is_enable (virtio_vring_buffering_t * buffering, + u8 is_enable) +{ + if (buffering) + buffering->is_enable = is_enable; +} + +static_always_inline void +virtio_vring_buffering_set_timeout (vlib_main_t * vm, + virtio_vring_buffering_t * buffering, + f64 timeout_expire) +{ + if (buffering) + buffering->timeout_ts = vlib_time_now (vm) + timeout_expire; +} + +static_always_inline u8 +virtio_vring_buffering_is_timeout (vlib_main_t * vm, + virtio_vring_buffering_t * buffering) +{ + if (buffering && (buffering->timeout_ts < vlib_time_now (vm))) + return 1; + return 0; +} + +static_always_inline u8 +virtio_vring_buffering_is_empty (virtio_vring_buffering_t * buffering) +{ + if (buffering->size == buffering->free_size) + return 1; + return 0; +} + +static_always_inline u8 +virtio_vring_buffering_is_full (virtio_vring_buffering_t * buffering) +{ + if (buffering->free_size == 0) + return 1; + return 0; +} + +static_always_inline u16 +virtio_vring_n_buffers (virtio_vring_buffering_t * buffering) +{ + return (buffering->size - buffering->free_size); +} + +static_always_inline u16 +virtio_vring_buffering_store_packets (virtio_vring_buffering_t * buffering, + u32 * bi, u16 n_store) +{ + u16 mask, n_s = 0, i = 0; + + if (!virtio_vring_buffering_is_enable (buffering) + || virtio_vring_buffering_is_full (buffering)) + return 0; + + mask = buffering->size - 1; + n_s = clib_min (n_store, buffering->free_size); + + while (i < n_s) + { + buffering->buffers[buffering->back] = bi[i]; + buffering->back = (buffering->back + 1) & mask; + buffering->free_size--; + i++; + } + return n_s; +} + +static_always_inline u32 +virtio_vring_buffering_read_from_front (virtio_vring_buffering_t * buffering) +{ + u32 bi = ~0; + u16 mask = buffering->size - 1; + if (virtio_vring_buffering_is_empty (buffering)) + return bi; + + bi = buffering->buffers[buffering->front]; + buffering->buffers[buffering->front] = ~0; + buffering->front = (buffering->front + 1) & mask; + buffering->free_size++; + return bi; +} + +static_always_inline u32 +virtio_vring_buffering_read_from_back (virtio_vring_buffering_t * buffering) +{ + u32 bi = ~0; + u16 mask = buffering->size - 1; + if (virtio_vring_buffering_is_empty (buffering)) + return bi; + + buffering->back = (buffering->back - 1) & mask; + bi = buffering->buffers[buffering->back]; + buffering->buffers[buffering->back] = ~0; + buffering->free_size++; + return bi; +} + +static_always_inline void +virtio_vring_buffering_schedule_node_on_dispatcher (vlib_main_t * vm, + virtio_vring_buffering_t * + buffering) +{ + if (buffering && virtio_vring_buffering_is_timeout (vm, buffering) + && virtio_vring_n_buffers (buffering)) + { + vlib_frame_t *f = vlib_get_frame_to_node (vm, buffering->node_index); + u32 *f_to = vlib_frame_vector_args (f); + f_to[f->n_vectors] = virtio_vring_buffering_read_from_back (buffering); + f->n_vectors++; + vlib_put_frame_to_node (vm, buffering->node_index, f); + virtio_vring_buffering_set_timeout (vm, buffering, + VIRTIO_BUFFERING_TIMEOUT); + } +} + +static_always_inline u8 * +virtio_vring_buffering_format (u8 * s, va_list * args) +{ + virtio_vring_buffering_t *buffering = + va_arg (*args, virtio_vring_buffering_t *); + u32 indent = format_get_indent (s); + + if (!buffering) + return s; + + indent += 2; + + if (buffering->is_enable) + s = format (s, "packet-buffering: enable\n"); + else + s = format (s, "packet-buffering: disable\n"); + s = + format (s, + "%Usize %u n_buffers %u front %u back %u", + format_white_space, indent, buffering->size, + virtio_vring_n_buffers (buffering), buffering->front, + buffering->back); + + return s; +} + +#endif /* _VNET_DEVICES_VIRTIO_VIRTIO_BUFFERING_H_ */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |