/*
* nsim.c - skeleton vpp engine plug-in
*
* Copyright (c) <current-year> <your-organization>
* 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.
*/
#include <vlib/vlib.h>
#include <vnet/vnet.h>
#include <vnet/pg/pg.h>
#include <vppinfra/error.h>
#include <nsim/nsim.h>
typedef struct
{
f64 expired;
u32 tx_sw_if_index;
} nsim_tx_trace_t;
#ifndef CLIB_MARCH_VARIANT
/* packet trace format function */
static u8 *
format_nsim_tx_trace (u8 * s, va_list * args)
{
CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
nsim_tx_trace_t *t = va_arg (*args, nsim_tx_trace_t *);
s = format (s, "NSIM: tx at %.6f sw_if_index %d",
t->expired, t->tx_sw_if_index);
return s;
}
#endif /* CLIB_MARCH_VARIANT */
#define foreach_nsim_tx_error \
_(TX, "Packets transmitted") \
_(DROPPED, "No buffer drops")
typedef enum
{
#define _(sym,str) NSIM_TX_ERROR_##sym,
foreach_nsim_tx_error
#undef _
NSIM_N_ERROR,
} nsim_tx_error_t;
#ifndef CLIB_MARCH_VARIANT
static char *nsim_tx_error_strings[] = {
#define _(sym,string) string,
foreach_nsim_tx_error
#undef _
};
#endif /* CLIB_MARCH_VARIANT */
typedef enum
{
NSIM_NEXT_DROP,
NSIM_N_NEXT,
} nsim_next_t;
always_inline uword
nsim_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
vlib_frame_t * f, int is_trace)
{
nsim_main_t *nsm = &nsim_main;
u32 my_thread_index = vm->thread_index;
u32 *my_buffer_cache = nsm->buffer_indices_by_thread[my_thread_index];
nsim_wheel_t *wp = nsm->wheel_by_thread[my_thread_index];
f64 now = vlib_time_now (vm);
uword n_rx_packets = 0;
vlib_buffer_t *b0;
u32 bi0, next0;
vlib_buffer_free_list_t *fl;
u32 *to_next;
u32 next_index;
u32 n_left_to_next;
nsim_wheel_entry_t *ep;
/* Nothing on the scheduler wheel? */
if (wp->cursize == 0)
return 0;
/* First entry on the wheel isn't expired? */
ep = wp->entries + wp->head;
if (ep->tx_time > now)
return n_rx_packets;
/*
* We use per-thread buffer caches, so we need the freelist to
* initialize them...
*/
fl = vlib_buffer_get_free_list (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
next_index = node->cached_next_index;
while (wp->cursize)
{
/* Be aware: this is not the usual coding pattern */
vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
while (n_left_to_next > 0 && ep->tx_time <= now)
{
/* Out of local buffer cache? */
if (PREDICT_FALSE (_vec_len (my_buffer_cache) == 0))
{
u32 n =
vlib_buffer_alloc (vm, my_buffer_cache, VLIB_FRAME_SIZE);
_vec_len (my_buffer_cache) = n;
/* Ugh, drop the rest of the expired entries */
if (n == 0)
{
u32 drops = 0;
while (ep->tx_time <= now && wp->cursize)
{
wp->head++;
if (wp->head == wp->wheel_size)
wp->head = 0;
ep = wp->entries + wp->head;
wp->cursize--;
drops++;
}
/* Count the drops */
vlib_node_increment_counter (vm, node->node_index,
NSIM_TX_ERROR_DROPPED, drops);
/* Ship any pkts we already processed */
vlib_put_next_frame (vm, node, next_index, n_left_to_next);
return n_rx_packets + drops;
}
}
/* Allocate a buffer */
bi0 = my_buffer_cache[_vec_len (my_buffer_cache) - 1];
_vec_len (my_buffer_cache) -= 1;
to_next[0] = bi0;
to_next += 1;
n_left_to_next -= 1;
b0 = vlib_get_buffer (vm, bi0);
/* Initialize the buffer */
vlib_buffer_init_for_free_list (b0, fl);
b0->current_data = 0;
b0->current_length = ep->current_length;
/* Copy data from the ring */
clib_memcpy (b0->data, ep->data, ep->current_length);
b0->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
vnet_buffer (b0)->sw_if_index[VLIB_TX] = ep->tx_sw_if_index;
vnet_buffer (b0)->sw_if_index[VLIB_RX] =
(ep->tx_sw_if_index == nsm->sw_if_index0) ? nsm->sw_if_index1 :
nsm->sw_if_index0;
next0 = (ep->tx_sw_if_index == nsm->sw_if_index0) ?
nsm->output_next_index0 : nsm->output_next_index1;
/* verify speculative enqueue, maybe switch current next frame */
vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
to_next, n_left_to_next,
bi0, next0);
/* Advance to the next ring entry */
wp->head++;
if (wp->head == wp->wheel_size)
wp->head = 0;
wp->cursize--;
ep = wp->entries + wp->head;
n_rx_packets++;
/* Out of ring entries? */
if (PREDICT_FALSE (wp->cursize == 0))
break;
}
vlib_put_next_frame (vm, node, next_index, n_left_to_next);
/* If the current entry hasn't expired, we're done */
if (ep->tx_time > now)
break;
}
return n_rx_packets;
}
VLIB_NODE_FN (nsim_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
vlib_frame_t * frame)
{
if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
return nsim_input_inline (vm, node, frame, 1 /* is_trace */ );
else
return nsim_input_inline (vm, node, frame, 0 /* is_trace */ );
}
/* *INDENT-OFF* */
#ifndef CLIB_MARCH_VARIANT
VLIB_REGISTER_NODE (nsim_input_node) =
{
.type = VLIB_NODE_TYPE_INPUT,
.name = "nsim-wheel",
/* Will be enabled if/when the feature is configured */
.state = VLIB_NODE_STATE_DISABLED,
.format_trace = format_nsim_tx_trace,
.n_errors = NSIM_N_ERROR,
.error_strings = nsim_tx_error_strings,
};
#endif /* CLIB_MARCH_VARIANT */
/* *INDENT-ON* */
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/
