diff options
| author |   Dave Barach <dave@barachs.net> | 2018-12-06 10:20:14 -0500 |
|---|---|---|
| committer |   Florin Coras <florin.coras@gmail.com> | 2018-12-06 18:28:47 +0000 |
| commit | 10c5ff143a86d15e78cb1f8625eb0ab8bf72b6ce (patch) | |
| tree | 00afabf7ca2ccd4042b2315b38fa6fb1bf5902c2 /src/plugins/nsim/node.c | |
| parent | 995ff06fb73a2d1ac8472977cf3089d763f17d33 (diff) | |
nsim: add packet loss simulation, docs
Change-Id: Ic9747541aad8148ebf7d520b525b99c4cc3961f3
Signed-off-by: Dave Barach <dave@barachs.net>
Diffstat (limited to 'src/plugins/nsim/node.c')
| -rw-r--r-- | src/plugins/nsim/node.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/src/plugins/nsim/node.c b/src/plugins/nsim/node.c index d6413778bf3..25112abe299 100644 --- a/src/plugins/nsim/node.c +++ b/src/plugins/nsim/node.c @@ -25,6 +25,7 @@ typedef struct f64 expires; u32 tx_sw_if_index; int is_drop; + int is_lost; } nsim_trace_t; #ifndef CLIB_MARCH_VARIANT @@ -38,7 +39,8 @@ format_nsim_trace (u8 * s, va_list * args) nsim_trace_t *t = va_arg (*args, nsim_trace_t *); if (t->is_drop) - s = format (s, "NSIM: ring drop"); + s = format (s, "NSIM: dropped, %s", t->is_lost ? + "simulated network loss" : "no space in ring"); else s = format (s, "NSIM: tx time %.6f sw_if_index %d", t->expires, t->tx_sw_if_index); @@ -51,7 +53,8 @@ vlib_node_registration_t nsim_node; #define foreach_nsim_error \ _(BUFFERED, "Packets buffered") \ -_(DROPPED, "Packets dropped due to lack of space") +_(DROPPED, "Packets dropped due to lack of space") \ +_(LOSS, "Network loss simulation drop packets") typedef enum { @@ -90,6 +93,7 @@ nsim_inline (vlib_main_t * vm, int is_drop0; u32 no_error = node->errors[NSIM_ERROR_BUFFERED]; u32 no_buffer_error = node->errors[NSIM_ERROR_DROPPED]; + u32 loss_error = node->errors[NSIM_ERROR_LOSS]; nsim_wheel_entry_t *ep = 0; ASSERT (wp); @@ -109,6 +113,19 @@ nsim_inline (vlib_main_t * vm, is_drop0 = 0; if (PREDICT_TRUE (wp->cursize < wp->wheel_size)) { + if (PREDICT_FALSE (nsm->drop_fraction != 0.0)) + { + /* Get a random number on the closed interval [0,1] */ + f64 rnd = random_f64 (&nsm->seed); + /* Drop the pkt? */ + if (rnd <= nsm->drop_fraction) + { + b[0]->error = loss_error; + is_drop0 = 1; + goto do_trace; + } + } + ep = wp->entries + wp->tail; wp->tail++; if (wp->tail == wp->wheel_size) @@ -130,6 +147,7 @@ nsim_inline (vlib_main_t * vm, is_drop0 = 1; } + do_trace: if (is_trace) { if (b[0]->flags & VLIB_BUFFER_IS_TRACED) @@ -137,6 +155,7 @@ nsim_inline (vlib_main_t * vm, nsim_trace_t *t = vlib_add_trace (vm, node, b[0], sizeof (*t)); t->expires = expires; t->is_drop = is_drop0; + t->is_lost = b[0]->error == loss_error; t->tx_sw_if_index = (is_drop0 == 0) ? ep->tx_sw_if_index : 0; } } |