From 1e1b09472ead5ababb8d007a05b0bf37eb633129 Mon Sep 17 00:00:00 2001
From: Adam Drescher <adam.r.drescher@gmail.com>
Date: Tue, 27 Aug 2019 15:13:07 +0000
Subject: [PATCH] programmable_rss: split out single queue case into separate
 function

Currently, the single queue case still prints all of the configured
queues for the NIC, even though only one is active. Instead of mucking
around with poll_stats() and the indirection map for multiple cases,
just split the single queue case off into a separate function. This
reuses the indirection map as a map to keep track of its stats
(purely out of convenience).
---
 programmable_rss/rss_user.c | 55 +++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/programmable_rss/rss_user.c b/programmable_rss/rss_user.c
index a278a41..04c1d5a 100644
--- a/programmable_rss/rss_user.c
+++ b/programmable_rss/rss_user.c
@@ -53,6 +53,46 @@ static int get_interface_rx_channels(int ifindex)
 	return cmd.combined_count + cmd.rx_count;
 }
 
+static int poll_stats_single_queue(int indirect_map_fd, int queue, int poll_secs)
+{
+	struct indirect_queue indirect_lookup;
+	int value = 0, prev = 0;
+	struct timespec t1, t2;
+	double time_taken;
+	long queue_rate;
+	int i = 0;
+
+	/* use thousand separators in printf */
+	setlocale(LC_NUMERIC, "en_US");
+
+	clock_gettime(CLOCK_MONOTONIC_RAW, &t1);
+
+	while (true) {
+		printf("-------------------------------------------------\n\n");
+		if (bpf_map_lookup_elem(indirect_map_fd,
+					&i, &indirect_lookup) != 0) {
+			printf("Err lookup failed\n");
+			return 0;
+		}
+
+		value = indirect_lookup.packet_cnt;
+
+		/* calc sample period to allow rate to be obtained */
+		clock_gettime(CLOCK_MONOTONIC_RAW, &t2);
+		time_taken = (t2.tv_sec + 1.0e-9 * t2.tv_nsec) -
+			     (t1.tv_sec + 1.0e-9 * t1.tv_nsec);
+
+		queue_rate = (value - prev) / time_taken;
+		printf("RSS Queue %d: %'ld\n", queue, queue_rate);
+		prev = value;
+		value = 0;
+
+		t1 = t2;
+		usleep(poll_secs * 1000 * 1000);
+	}
+}
+
+
 static int poll_stats(int indirect_map_fd, int queues_enabled, int poll_secs)
 {
 	struct indirect_queue indirect_lookup;
@@ -231,6 +271,21 @@ int main(int argc, char **argv)
 		return -1;
 	}
 
+	/* use indirection map for stats in the single queue case */
+	if (mapctrl.select_mode == QUEUE_STATIC) {
+		indirect_rec.queue_num = mapctrl.queue_static;
+		i = 0;
+
+		if (bpf_map_update_elem(indirect_map_fd, &i, &indirect_rec,
+					BPF_ANY) != 0) {
+			printf("Err: Map update failed\n");
+			return -1;
+		}
+
+		poll_stats_single_queue(indirect_map_fd, mapctrl.queue_static, 1);
+		return 0;
+	}
+
 	/* fill ctrl map with hash mode queues */
 	key = 0;
 	if (bpf_map_update_elem(ctrl_map_fd, &key, &mapctrl, BPF_ANY) != 0) {