This commit adds support for configuring HTB in offload mode. HTB
offload eliminates the single qdisc lock in the datapath and offloads
the algorithm to the NIC. The new 'offload' parameter is added to
enable this mode:
# tc qdisc replace dev eth0 root handle 1: htb offload
Classes are created as usual, but filters should be moved to clsact for
lock-free classification (filters attached to HTB itself are not
supported in the offload mode):
# tc filter add dev eth0 egress protocol ip flower dst_port 80
action skbedit priority 1:10
Signed-off-by: Maxim Mikityanskiy <maxi...@mellanox.com>
Reviewed-by: Tariq Toukan <tar...@nvidia.com>
---
tc/q_htb.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/tc/q_htb.c b/tc/q_htb.c
index c609e974..cfc408dd 100644
--- a/tc/q_htb.c
+++ b/tc/q_htb.c
@@ -30,11 +30,12 @@
static void explain(void)
{
fprintf(stderr, "Usage: ... qdisc add ... htb [default N] [r2q N]\n"
- " [direct_qlen P]\n"
+ " [direct_qlen P] [offload]\n"
" default minor id of class to which unclassified packets are
sent {0}\n"
" r2q DRR quantums are computed as rate in Bps/r2q {10}\n"
" debug string of 16 numbers each 0-3 {0}\n\n"
" direct_qlen Limit of the direct queue {in packets}\n"
+ " offload hardware offload\n"
"... class add ... htb rate R1 [burst B1] [mpu B] [overhead
O]\n"
" [prio P] [slot S] [pslot PS]\n"
" [ceil R2] [cburst B2] [mtu MTU] [quantum
Q]\n"
@@ -68,6 +69,7 @@ static int htb_parse_opt(struct qdisc_util *qu, int argc,
};
struct rtattr *tail;
unsigned int i; char *p;
+ bool offload = false;
while (argc > 0) {
if (matches(*argv, "r2q") == 0) {
@@ -91,6 +93,8 @@ static int htb_parse_opt(struct qdisc_util *qu, int argc,
if (get_u32(&direct_qlen, *argv, 10)) {
explain1("direct_qlen"); return -1;
}
+ } else if (matches(*argv, "offload") == 0) {
+ offload = true;
} else {
fprintf(stderr, "What is \"%s\"?\n", *argv);
explain();
@@ -103,6 +107,8 @@ static int htb_parse_opt(struct qdisc_util *qu, int argc,
if (direct_qlen != ~0U)
addattr_l(n, 2024, TCA_HTB_DIRECT_QLEN,
&direct_qlen, sizeof(direct_qlen));
+ if (offload)
+ addattr(n, 2024, TCA_HTB_OFFLOAD);
addattr_nest_end(n, tail);
return 0;
}
@@ -344,6 +350,8 @@ static int htb_print_opt(struct qdisc_util *qu, FILE *f,
struct rtattr *opt)
print_uint(PRINT_ANY, "direct_qlen", " direct_qlen %u",
direct_qlen);
}
+ if (tb[TCA_HTB_OFFLOAD])
+ print_null(PRINT_ANY, "offload", " offload", NULL);
return 0;
}
--
2.25.1
