Thread-safe ARP / ND throttling
Change-Id: I810d834c407bd404d5f0544cdec0674f0bb92d31
Signed-off-by: Dave Barach <dave@barachs.net>
Signed-off-by: Dave Barach <dbarach@cisco.com>
diff --git a/src/vnet/ip/ip4.h b/src/vnet/ip/ip4.h
index fcef559..e3cbe27 100644
--- a/src/vnet/ip/ip4.h
+++ b/src/vnet/ip/ip4.h
@@ -154,8 +154,16 @@
/** The memory heap for the mtries */
void *mtrie_mheap;
+
+ /** ARP throttling */
+ uword **arp_throttle_bitmaps;
+ u32 *arp_throttle_seeds;
+ f64 *arp_throttle_last_seed_change_time;
+
} ip4_main_t;
+#define ARP_THROTTLE_BITS (512)
+
/** Global ip4 main structure. */
extern ip4_main_t ip4_main;
diff --git a/src/vnet/ip/ip4_forward.c b/src/vnet/ip/ip4_forward.c
index 8d4aead..11bcf3a 100644
--- a/src/vnet/ip/ip4_forward.c
+++ b/src/vnet/ip/ip4_forward.c
@@ -1722,29 +1722,23 @@
ip_lookup_main_t *lm = &im->lookup_main;
u32 *from, *to_next_drop;
uword n_left_from, n_left_to_next_drop, next_index;
- static f64 time_last_seed_change = -1e100;
- static u32 hash_seeds[3];
- static uword hash_bitmap[256 / BITS (uword)];
+ u32 thread_index = vm->thread_index;
+ u32 seed;
f64 time_now;
if (node->flags & VLIB_NODE_FLAG_TRACE)
ip4_forward_next_trace (vm, node, frame, VLIB_TX);
time_now = vlib_time_now (vm);
- if (time_now - time_last_seed_change > 1e-3)
+ if (time_now - im->arp_throttle_last_seed_change_time[thread_index] > 1e-3)
{
- uword i;
- u32 *r = clib_random_buffer_get_data (&vm->random_buffer,
- sizeof (hash_seeds));
- for (i = 0; i < ARRAY_LEN (hash_seeds); i++)
- hash_seeds[i] = r[i];
+ (void) random_u32 (&im->arp_throttle_seeds[thread_index]);
+ memset (im->arp_throttle_bitmaps[thread_index], 0,
+ ARP_THROTTLE_BITS / BITS (u8));
- /* Mark all hash keys as been no-seen before. */
- for (i = 0; i < ARRAY_LEN (hash_bitmap); i++)
- hash_bitmap[i] = 0;
-
- time_last_seed_change = time_now;
+ im->arp_throttle_last_seed_change_time[thread_index] = time_now;
}
+ seed = im->arp_throttle_seeds[thread_index];
from = vlib_frame_vector_args (frame);
n_left_from = frame->n_vectors;
@@ -1759,11 +1753,11 @@
while (n_left_from > 0 && n_left_to_next_drop > 0)
{
- u32 pi0, adj_index0, a0, b0, c0, m0, sw_if_index0, drop0;
+ u32 pi0, adj_index0, r0, w0, sw_if_index0, drop0;
+ uword m0;
ip_adjacency_t *adj0;
vlib_buffer_t *p0;
ip4_header_t *ip0;
- uword bm0;
pi0 = from[0];
@@ -1773,39 +1767,30 @@
adj0 = adj_get (adj_index0);
ip0 = vlib_buffer_get_current (p0);
- a0 = hash_seeds[0];
- b0 = hash_seeds[1];
- c0 = hash_seeds[2];
-
sw_if_index0 = adj0->rewrite_header.sw_if_index;
vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
- if (is_glean)
+ if (PREDICT_TRUE (is_glean))
{
/*
* this is the Glean case, so we are ARPing for the
* packet's destination
*/
- a0 ^= ip0->dst_address.data_u32;
+ r0 = ip0->dst_address.data_u32;
}
else
{
- a0 ^= adj0->sub_type.nbr.next_hop.ip4.data_u32;
+ r0 = adj0->sub_type.nbr.next_hop.ip4.data_u32;
}
- b0 ^= sw_if_index0;
- hash_v3_mix32 (a0, b0, c0);
- hash_v3_finalize32 (a0, b0, c0);
+ r0 ^= seed;
+ /* Select bit number */
+ r0 &= ARP_THROTTLE_BITS - 1;
+ w0 = r0 / BITS (uword);
+ m0 = (uword) 1 << (r0 % BITS (uword));
- c0 &= BITS (hash_bitmap) - 1;
- m0 = (uword) 1 << (c0 % BITS (uword));
- c0 = c0 / BITS (uword);
-
- bm0 = hash_bitmap[c0];
- drop0 = (bm0 & m0) != 0;
-
- /* Mark it as seen. */
- hash_bitmap[c0] = bm0 | m0;
+ drop0 = (im->arp_throttle_bitmaps[thread_index][w0] & m0) != 0;
+ im->arp_throttle_bitmaps[thread_index][w0] |= m0;
from += 1;
n_left_from -= 1;
diff --git a/src/vnet/ip/ip4_input.c b/src/vnet/ip/ip4_input.c
index 971445c..d11d558 100644
--- a/src/vnet/ip/ip4_input.c
+++ b/src/vnet/ip/ip4_input.c
@@ -383,6 +383,28 @@
}
VLIB_INIT_FUNCTION (ip4_init);
+
+static clib_error_t *
+ip4_main_loop_enter (vlib_main_t * vm)
+{
+ ip4_main_t *im = &ip4_main;
+ vlib_thread_main_t *tm = &vlib_thread_main;
+ u32 n_vlib_mains = tm->n_vlib_mains;
+ int i;
+
+
+ vec_validate (im->arp_throttle_bitmaps, n_vlib_mains);
+ vec_validate (im->arp_throttle_seeds, n_vlib_mains);
+ vec_validate (im->arp_throttle_last_seed_change_time, n_vlib_mains);
+
+ for (i = 0; i < n_vlib_mains; i++)
+ vec_validate (im->arp_throttle_bitmaps[i],
+ (ARP_THROTTLE_BITS / BITS (uword)) - 1);
+ return 0;
+}
+
+VLIB_MAIN_LOOP_ENTER_FUNCTION (ip4_main_loop_enter);
+
#endif
/*
diff --git a/src/vnet/ip/ip6.h b/src/vnet/ip/ip6.h
index 8b1516c..a6feec5 100644
--- a/src/vnet/ip/ip6.h
+++ b/src/vnet/ip/ip6.h
@@ -219,8 +219,16 @@
/* HBH processing enabled? */
u8 hbh_enabled;
+
+ /** ND throttling */
+ uword **nd_throttle_bitmaps;
+ u64 *nd_throttle_seeds;
+ f64 *nd_throttle_last_seed_change_time;
+
} ip6_main_t;
+#define ND_THROTTLE_BITS 512
+
/* Global ip6 main structure. */
extern ip6_main_t ip6_main;
diff --git a/src/vnet/ip/ip6_input.c b/src/vnet/ip/ip6_input.c
index 6a7669d..977d270 100644
--- a/src/vnet/ip/ip6_input.c
+++ b/src/vnet/ip/ip6_input.c
@@ -246,8 +246,10 @@
};
/* *INDENT-ON* */
-VLIB_NODE_FUNCTION_MULTIARCH (ip6_input_node, ip6_input)
- static clib_error_t *ip6_init (vlib_main_t * vm)
+VLIB_NODE_FUNCTION_MULTIARCH (ip6_input_node, ip6_input);
+
+static clib_error_t *
+ip6_init (vlib_main_t * vm)
{
ethernet_register_input_type (vm, ETHERNET_TYPE_IP6, ip6_input_node.index);
ppp_register_input_protocol (vm, PPP_PROTOCOL_ip6, ip6_input_node.index);
@@ -270,6 +272,26 @@
VLIB_INIT_FUNCTION (ip6_init);
+static clib_error_t *
+ip6_main_loop_enter (vlib_main_t * vm)
+{
+ ip6_main_t *im = &ip6_main;
+ vlib_thread_main_t *tm = &vlib_thread_main;
+ u32 n_vlib_mains = tm->n_vlib_mains;
+ int i;
+
+ vec_validate (im->nd_throttle_bitmaps, n_vlib_mains);
+ vec_validate (im->nd_throttle_seeds, n_vlib_mains);
+ vec_validate (im->nd_throttle_last_seed_change_time, n_vlib_mains);
+
+ for (i = 0; i < n_vlib_mains; i++)
+ vec_validate (im->nd_throttle_bitmaps[i],
+ (ND_THROTTLE_BITS / BITS (uword)) - 1);
+ return 0;
+}
+
+VLIB_MAIN_LOOP_ENTER_FUNCTION (ip6_main_loop_enter);
+
/*
* fd.io coding-style-patch-verification: ON
*
diff --git a/src/vnet/ip/ip6_neighbor.c b/src/vnet/ip/ip6_neighbor.c
index 6227ed6..fff8174 100644
--- a/src/vnet/ip/ip6_neighbor.c
+++ b/src/vnet/ip/ip6_neighbor.c
@@ -3165,10 +3165,9 @@
ip_lookup_main_t *lm = &im->lookup_main;
u32 *from, *to_next_drop;
uword n_left_from, n_left_to_next_drop;
- static f64 time_last_seed_change = -1e100;
- static u32 hash_seeds[3];
- static uword hash_bitmap[256 / BITS (uword)];
f64 time_now;
+ u64 seed;
+ u32 thread_index = vm->thread_index;
int bogus_length;
ip6_neighbor_main_t *nm = &ip6_neighbor_main;
@@ -3176,20 +3175,15 @@
ip6_forward_next_trace (vm, node, frame, VLIB_TX);
time_now = vlib_time_now (vm);
- if (time_now - time_last_seed_change > 1e-3)
+ if (time_now - im->nd_throttle_last_seed_change_time[thread_index] > 1e-3)
{
- uword i;
- u32 *r = clib_random_buffer_get_data (&vm->random_buffer,
- sizeof (hash_seeds));
- for (i = 0; i < ARRAY_LEN (hash_seeds); i++)
- hash_seeds[i] = r[i];
+ (void) random_u64 (&im->nd_throttle_seeds[thread_index]);
+ memset (im->nd_throttle_bitmaps[thread_index], 0,
+ ND_THROTTLE_BITS / BITS (u8));
- /* Mark all hash keys as been not-seen before. */
- for (i = 0; i < ARRAY_LEN (hash_bitmap); i++)
- hash_bitmap[i] = 0;
-
- time_last_seed_change = time_now;
+ im->nd_throttle_last_seed_change_time[thread_index] = time_now;
}
+ seed = im->nd_throttle_seeds[thread_index];
from = vlib_frame_vector_args (frame);
n_left_from = frame->n_vectors;
@@ -3203,8 +3197,9 @@
{
vlib_buffer_t *p0;
ip6_header_t *ip0;
- u32 pi0, adj_index0, a0, b0, c0, m0, sw_if_index0, drop0;
- uword bm0;
+ u32 pi0, adj_index0, w0, sw_if_index0, drop0;
+ u64 r0;
+ uword m0;
ip_adjacency_t *adj0;
vnet_hw_interface_t *hw_if0;
ip6_radv_t *radv_info;
@@ -3228,33 +3223,21 @@
adj0->sub_type.nbr.next_hop.ip6.as_u64[1];
}
- a0 = hash_seeds[0];
- b0 = hash_seeds[1];
- c0 = hash_seeds[2];
-
sw_if_index0 = adj0->rewrite_header.sw_if_index;
vnet_buffer (p0)->sw_if_index[VLIB_TX] = sw_if_index0;
- a0 ^= sw_if_index0;
- b0 ^= ip0->dst_address.as_u32[0];
- c0 ^= ip0->dst_address.as_u32[1];
+ /* Compute the ND throttle bitmap hash */
+ r0 = ip0->dst_address.as_u64[0] ^ ip0->dst_address.as_u64[1] ^ seed;
- hash_v3_mix32 (a0, b0, c0);
+ /* Find the word and bit */
+ r0 &= ND_THROTTLE_BITS - 1;
+ w0 = r0 / BITS (uword);
+ m0 = (uword) 1 << (r0 % BITS (uword));
- b0 ^= ip0->dst_address.as_u32[2];
- c0 ^= ip0->dst_address.as_u32[3];
-
- hash_v3_finalize32 (a0, b0, c0);
-
- c0 &= BITS (hash_bitmap) - 1;
- c0 = c0 / BITS (uword);
- m0 = (uword) 1 << (c0 % BITS (uword));
-
- bm0 = hash_bitmap[c0];
- drop0 = (bm0 & m0) != 0;
-
- /* Mark it as seen. */
- hash_bitmap[c0] = bm0 | m0;
+ /* If the bit is set, drop the ND request */
+ drop0 = (im->nd_throttle_bitmaps[thread_index][w0] & m0) != 0;
+ /* (unconditionally) mark the bit "inuse" */
+ im->nd_throttle_bitmaps[thread_index][w0] |= m0;
from += 1;
n_left_from -= 1;