[PATCH iproute2] fq_codel: add per queue memory limit

[Eric Dumazet]

From: Eric Dumazet <eduma...@google.com>

This patch adds support for TCA_FQ_CODEL_MEMORY_LIMIT attribute.

# tc qd replace dev eth1 root est 1sec 4sec fq_codel memory_limit 4M
..
# tc -s -d qd sh dev eth1
qdisc fq_codel 8008: root refcnt 257 limit 10240p flows 1024
 quantum 1514 target 5.0ms interval 100.0ms memory_limit 4Mb ecn
 Sent 2083566791363 bytes 1376214889 pkt (dropped 4994406, overlimits 0
requeues 21705223)
 rate 9841Mbit 812549pps backlog 3906120b 376p requeues 21705223
  maxpacket 68130 drop_overlimit 4994406 new_flow_count 28855414
  ecn_mark 0 memory_used 4190048 drop_overmemory 4994406
new_flows_len 1 old_flows_len 177

Signed-off-by: Eric Dumazet <eduma...@google.com>
---
 tc/q_fq_codel.c |   22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/tc/q_fq_codel.c b/tc/q_fq_codel.c
index 4f747eb..c0137a7 100644
--- a/tc/q_fq_codel.c
+++ b/tc/q_fq_codel.c
@@ -65,6 +65,7 @@ static int fq_codel_parse_opt(struct qdisc_util *qu, int 
argc, char **argv,
        unsigned interval = 0;
        unsigned quantum = 0;
        unsigned ce_threshold = ~0U;
+       unsigned memory = ~0U;
        int ecn = -1;
        struct rtattr *tail;
 
@@ -99,6 +100,12 @@ static int fq_codel_parse_opt(struct qdisc_util *qu, int 
argc, char **argv,
                                fprintf(stderr, "Illegal \"ce_threshold\"\n");
                                return -1;
                        }
+               } else if (strcmp(*argv, "memory_limit") == 0) {
+                       NEXT_ARG();
+                       if (get_size(&memory, *argv)) {
+                               fprintf(stderr, "Illegal \"memory_limit\"\n");
+                               return -1;
+                       }
                } else if (strcmp(*argv, "interval") == 0) {
                        NEXT_ARG();
                        if (get_time(&interval, *argv)) {
@@ -137,6 +144,10 @@ static int fq_codel_parse_opt(struct qdisc_util *qu, int 
argc, char **argv,
        if (ce_threshold != ~0U)
                addattr_l(n, 1024, TCA_FQ_CODEL_CE_THRESHOLD,
                          &ce_threshold, sizeof(ce_threshold));
+       if (memory != ~0U)
+               addattr_l(n, 1024, TCA_FQ_CODEL_MEMORY_LIMIT,
+                         &memory, sizeof(memory));
+
        tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
        return 0;
 }
@@ -151,6 +162,7 @@ static int fq_codel_print_opt(struct qdisc_util *qu, FILE 
*f, struct rtattr *opt
        unsigned ecn;
        unsigned quantum;
        unsigned ce_threshold;
+       unsigned memory_limit;
        SPRINT_BUF(b1);
 
        if (opt == NULL)
@@ -188,6 +200,12 @@ static int fq_codel_print_opt(struct qdisc_util *qu, FILE 
*f, struct rtattr *opt
                interval = rta_getattr_u32(tb[TCA_FQ_CODEL_INTERVAL]);
                fprintf(f, "interval %s ", sprint_time(interval, b1));
        }
+       if (tb[TCA_FQ_CODEL_MEMORY_LIMIT] &&
+           RTA_PAYLOAD(tb[TCA_FQ_CODEL_MEMORY_LIMIT]) >= sizeof(__u32)) {
+               memory_limit = rta_getattr_u32(tb[TCA_FQ_CODEL_MEMORY_LIMIT]);
+
+               fprintf(f, "memory_limit %s ", sprint_size(memory_limit, b1));
+       }
        if (tb[TCA_FQ_CODEL_ECN] &&
            RTA_PAYLOAD(tb[TCA_FQ_CODEL_ECN]) >= sizeof(__u32)) {
                ecn = rta_getattr_u32(tb[TCA_FQ_CODEL_ECN]);
@@ -221,6 +239,10 @@ static int fq_codel_print_xstats(struct qdisc_util *qu, 
FILE *f,
                        st->qdisc_stats.ecn_mark);
                if (st->qdisc_stats.ce_mark)
                        fprintf(f, " ce_mark %u", st->qdisc_stats.ce_mark);
+               if (st->qdisc_stats.memory_usage)
+                       fprintf(f, " memory_used %u", 
st->qdisc_stats.memory_usage);
+               if (st->qdisc_stats.drop_overmemory)
+                       fprintf(f, " drop_overmemory %u", 
st->qdisc_stats.drop_overmemory);
                fprintf(f, "\n  new_flows_len %u old_flows_len %u",
                        st->qdisc_stats.new_flows_len,
                        st->qdisc_stats.old_flows_len);