tc: fq: add support for JSON output

Enable proper JSON output for the FQ Qdisc.
Use the "KEY VALUE" format for oneline output of statistics instead of
"VALUE KEY", and remove unnecessary commas from the output.
Use sprint_size() to print size values in fq_print_opt().
Use sprint_time64() to print time values in fq_print_xstats().
Also, update the man page to reflect the changes in the output format.

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>

2 files changed, 83 insertions, 39 deletions

diff --git a/man/man8/tc-fq.8 b/man/man8/tc-fq.8
index 1febe62bb..27385aaed 100644
--- a/man/man8/tc-fq.8
+++ b/man/man8/tc-fq.8
@@ -90,15 +90,15 @@ Experienced. This is useful for DCTCP-style congestion control algorithms that
 require marking at very shallow queueing thresholds.
 
 .SH EXAMPLES
-#tc qdisc add dev eth0 root est 1sec 4sec fq ce_threshold 4ms
+#tc qdisc add dev eth0 root fq ce_threshold 4ms
 .br
-#tc -s -d qdisc sh dev eth0
+#tc -s -d qdisc show dev eth0
 .br
-qdisc fq 800e: root refcnt 9 limit 10000p flow_limit 1000p buckets 1024 orphan_mask 1023 quantum 3028 initial_quantum 15140 low_rate_threshold 550Kbit refill_delay 40.0ms ce_threshold 4.0ms
- Sent 533368436185 bytes 352296695 pkt (dropped 0, overlimits 0 requeues 1339864)
- rate 39220Mbit 3238202pps backlog 12417828b 358p requeues 1339864
-  1052 flows (852 inactive, 0 throttled)
-  112 gc, 0 highprio, 212 throttled, 21501 ns latency, 470241 ce_mark
+qdisc fq 8001: dev eth0 root refcnt 2 limit 10000p flow_limit 100p buckets 1024 orphan_mask 1023 quantum 3028b initial_quantum 15140b low_rate_threshold 550Kbit refill_delay 40.0ms ce_threshold 4.0ms
+ Sent 72149092 bytes 48062 pkt (dropped 2176, overlimits 0 requeues 0)
+ backlog 1937920b 1280p requeues 0
+  flows 34 (inactive 17 throttled 0)
+  gc 0 highprio 0 throttled 0 ce_mark 47622 flows_plimit 2176
 .br
 .SH SEE ALSO
 .BR tc (8),
diff --git a/tc/q_fq.c b/tc/q_fq.c
index caf232ec4..44d8a7e03 100644
--- a/tc/q_fq.c
+++ b/tc/q_fq.c
@@ -265,71 +265,94 @@ static int fq_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
 	if (tb[TCA_FQ_PLIMIT] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_PLIMIT]) >= sizeof(__u32)) {
 		plimit = rta_getattr_u32(tb[TCA_FQ_PLIMIT]);
-		fprintf(f, "limit %up ", plimit);
+		print_uint(PRINT_ANY, "limit", "limit %up ", plimit);
 	}
 	if (tb[TCA_FQ_FLOW_PLIMIT] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_FLOW_PLIMIT]) >= sizeof(__u32)) {
 		flow_plimit = rta_getattr_u32(tb[TCA_FQ_FLOW_PLIMIT]);
-		fprintf(f, "flow_limit %up ", flow_plimit);
+		print_uint(PRINT_ANY, "flow_limit", "flow_limit %up ",
+			   flow_plimit);
 	}
 	if (tb[TCA_FQ_BUCKETS_LOG] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_BUCKETS_LOG]) >= sizeof(__u32)) {
 		buckets_log = rta_getattr_u32(tb[TCA_FQ_BUCKETS_LOG]);
-		fprintf(f, "buckets %u ", 1U << buckets_log);
+		print_uint(PRINT_ANY, "buckets", "buckets %u ",
+			   1U << buckets_log);
 	}
 	if (tb[TCA_FQ_ORPHAN_MASK] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_ORPHAN_MASK]) >= sizeof(__u32)) {
 		orphan_mask = rta_getattr_u32(tb[TCA_FQ_ORPHAN_MASK]);
-		fprintf(f, "orphan_mask %u ", orphan_mask);
+		print_uint(PRINT_ANY, "orphan_mask", "orphan_mask %u ",
+			   orphan_mask);
 	}
 	if (tb[TCA_FQ_RATE_ENABLE] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_RATE_ENABLE]) >= sizeof(int)) {
 		pacing = rta_getattr_u32(tb[TCA_FQ_RATE_ENABLE]);
 		if (pacing == 0)
-			fprintf(f, "nopacing ");
+			print_bool(PRINT_ANY, "pacing", "nopacing ", false);
 	}
 	if (tb[TCA_FQ_QUANTUM] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_QUANTUM]) >= sizeof(__u32)) {
 		quantum = rta_getattr_u32(tb[TCA_FQ_QUANTUM]);
-		fprintf(f, "quantum %u ", quantum);
+		print_uint(PRINT_JSON, "quantum", NULL, quantum);
+		print_string(PRINT_FP, NULL, "quantum %s ",
+			     sprint_size(quantum, b1));
 	}
 	if (tb[TCA_FQ_INITIAL_QUANTUM] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_INITIAL_QUANTUM]) >= sizeof(__u32)) {
 		quantum = rta_getattr_u32(tb[TCA_FQ_INITIAL_QUANTUM]);
-		fprintf(f, "initial_quantum %u ", quantum);
+		print_uint(PRINT_JSON, "initial_quantum", NULL, quantum);
+		print_string(PRINT_FP, NULL, "initial_quantum %s ",
+			     sprint_size(quantum, b1));
 	}
 	if (tb[TCA_FQ_FLOW_MAX_RATE] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_FLOW_MAX_RATE]) >= sizeof(__u32)) {
 		rate = rta_getattr_u32(tb[TCA_FQ_FLOW_MAX_RATE]);
 
-		if (rate != ~0U)
-			fprintf(f, "maxrate %s ", sprint_rate(rate, b1));
+		if (rate != ~0U) {
+			print_uint(PRINT_JSON, "maxrate", NULL, rate);
+			print_string(PRINT_FP, NULL, "maxrate %s ",
+				     sprint_rate(rate, b1));
+		}
 	}
 	if (tb[TCA_FQ_FLOW_DEFAULT_RATE] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_FLOW_DEFAULT_RATE]) >= sizeof(__u32)) {
 		rate = rta_getattr_u32(tb[TCA_FQ_FLOW_DEFAULT_RATE]);
 
-		if (rate != 0)
-			fprintf(f, "defrate %s ", sprint_rate(rate, b1));
+		if (rate != 0) {
+			print_uint(PRINT_JSON, "defrate", NULL, rate);
+			print_string(PRINT_FP, NULL, "defrate %s ",
+				     sprint_rate(rate, b1));
+		}
 	}
 	if (tb[TCA_FQ_LOW_RATE_THRESHOLD] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_LOW_RATE_THRESHOLD]) >= sizeof(__u32)) {
 		rate = rta_getattr_u32(tb[TCA_FQ_LOW_RATE_THRESHOLD]);
 
-		if (rate != 0)
-			fprintf(f, "low_rate_threshold %s ", sprint_rate(rate, b1));
+		if (rate != 0) {
+			print_uint(PRINT_JSON, "low_rate_threshold", NULL,
+				   rate);
+			print_string(PRINT_FP, NULL, "low_rate_threshold %s ",
+				     sprint_rate(rate, b1));
+		}
 	}
 	if (tb[TCA_FQ_FLOW_REFILL_DELAY] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_FLOW_REFILL_DELAY]) >= sizeof(__u32)) {
 		refill_delay = rta_getattr_u32(tb[TCA_FQ_FLOW_REFILL_DELAY]);
-		fprintf(f, "refill_delay %s ", sprint_time(refill_delay, b1));
+		print_uint(PRINT_JSON, "refill_delay", NULL, refill_delay);
+		print_string(PRINT_FP, NULL, "refill_delay %s ",
+			     sprint_time(refill_delay, b1));
 	}
 
 	if (tb[TCA_FQ_CE_THRESHOLD] &&
 	    RTA_PAYLOAD(tb[TCA_FQ_CE_THRESHOLD]) >= sizeof(__u32)) {
 		ce_threshold = rta_getattr_u32(tb[TCA_FQ_CE_THRESHOLD]);
-		if (ce_threshold != ~0U)
-			fprintf(f, "ce_threshold %s ", sprint_time(ce_threshold, b1));
+		if (ce_threshold != ~0U) {
+			print_uint(PRINT_JSON, "ce_threshold", NULL,
+				   ce_threshold);
+			print_string(PRINT_FP, NULL, "ce_threshold %s ",
+				     sprint_time(ce_threshold, b1));
+		}
 	}
 
 	return 0;
@@ -340,6 +363,8 @@ static int fq_print_xstats(struct qdisc_util *qu, FILE *f,
 {
 	struct tc_fq_qd_stats *st, _st;
 
+	SPRINT_BUF(b1);
+
 	if (xstats == NULL)
 		return 0;
 
@@ -348,32 +373,51 @@ static int fq_print_xstats(struct qdisc_util *qu, FILE *f,
 
 	st = &_st;
 
-	fprintf(f, "  %u flows (%u inactive, %u throttled)",
-		st->flows, st->inactive_flows, st->throttled_flows);
+	print_uint(PRINT_ANY, "flows", "  flows %u", st->flows);
+	print_uint(PRINT_ANY, "inactive", " (inactive %u", st->inactive_flows);
+	print_uint(PRINT_ANY, "throttled", " throttled %u)",
+		   st->throttled_flows);
 
-	if (st->time_next_delayed_flow > 0)
-		fprintf(f, ", next packet delay %llu ns", st->time_next_delayed_flow);
+	if (st->time_next_delayed_flow > 0) {
+		print_lluint(PRINT_JSON, "next_packet_delay", NULL,
+			     st->time_next_delayed_flow);
+		print_string(PRINT_FP, NULL, " next_packet_delay %s",
+			     sprint_time64(st->time_next_delayed_flow, b1));
+	}
 
-	fprintf(f, "\n  %llu gc, %llu highprio",
-		st->gc_flows, st->highprio_packets);
+	print_nl();
+	print_lluint(PRINT_ANY, "gc", "  gc %llu", st->gc_flows);
+	print_lluint(PRINT_ANY, "highprio", " highprio %llu",
+		     st->highprio_packets);
 
 	if (st->tcp_retrans)
-		fprintf(f, ", %llu retrans", st->tcp_retrans);
+		print_lluint(PRINT_ANY, "retrans", " retrans %llu",
+			     st->tcp_retrans);
 
-	fprintf(f, ", %llu throttled", st->throttled);
+	print_lluint(PRINT_ANY, "throttled", " throttled %llu", st->throttled);
 
-	if (st->unthrottle_latency_ns)
-		fprintf(f, ", %u ns latency", st->unthrottle_latency_ns);
+	if (st->unthrottle_latency_ns) {
+		print_uint(PRINT_JSON, "latency", NULL,
+			   st->unthrottle_latency_ns);
+		print_string(PRINT_FP, NULL, " latency %s",
+			     sprint_time64(st->unthrottle_latency_ns, b1));
+	}
 
 	if (st->ce_mark)
-		fprintf(f, ", %llu ce_mark", st->ce_mark);
+		print_lluint(PRINT_ANY, "ce_mark", " ce_mark %llu",
+			     st->ce_mark);
 
 	if (st->flows_plimit)
-		fprintf(f, ", %llu flows_plimit", st->flows_plimit);
-
-	if (st->pkts_too_long || st->allocation_errors)
-		fprintf(f, "\n  %llu too long pkts, %llu alloc errors\n",
-			st->pkts_too_long, st->allocation_errors);
+		print_lluint(PRINT_ANY, "flows_plimit", " flows_plimit %llu",
+			     st->flows_plimit);
+
+	if (st->pkts_too_long || st->allocation_errors) {
+		print_nl();
+		print_lluint(PRINT_ANY, "pkts_too_long",
+			     "  pkts_too_long %llu", st->pkts_too_long);
+		print_lluint(PRINT_ANY, "alloc_errors", " alloc_erros %llu",
+			     st->allocation_errors);
+	}
 
 	return 0;
 }