From: Daniel Salzman <daniel.salzman@nic.cz>
Date: Thu, 25 Jan 2024 08:56:11 +0000 (+0100)
Subject: xdp: add knot_xdp_socket_stats()
X-Git-Tag: v3.4.0~139^2~9
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ddf9b79b2cb467005cad9a63b724400a4dac26c3;p=thirdparty%2Fknot-dns.git

xdp: add knot_xdp_socket_stats()
---

diff --git a/src/libknot/xdp/xdp.c b/src/libknot/xdp/xdp.c
index fd4c88c285..e7acadf35a 100644
--- a/src/libknot/xdp/xdp.c
+++ b/src/libknot/xdp/xdp.c
@@ -537,6 +537,9 @@ void knot_xdp_recv_finish(knot_xdp_socket_t *socket, const knot_xdp_msg_t msgs[]
 	xsk_ring_prod__submit(fq, count);
 }
 
+// The number of busy frames
+#define RING_BUSY(ring) ((*(ring)->producer - *(ring)->consumer) & (ring)->mask)
+
 _public_
 void knot_xdp_socket_info(const knot_xdp_socket_t *socket, FILE *file)
 {
@@ -544,10 +547,6 @@ void knot_xdp_socket_info(const knot_xdp_socket_t *socket, FILE *file)
 		return;
 	}
 
-	// The number of busy frames
-	#define RING_BUSY(ring) \
-		((*(ring)->producer - *(ring)->consumer) & (ring)->mask)
-
 	#define RING_PRINFO(name, ring) \
 		fprintf(file, "Ring %s: size %4d, busy %4d (prod %4d, cons %4d)\n", \
 		        name, (unsigned)(ring)->size, \
@@ -567,3 +566,39 @@ void knot_xdp_socket_info(const knot_xdp_socket_t *socket, FILE *file)
 	RING_PRINFO("CQ", &socket->umem->cq);
 	fprintf(file, "TX free frames: %4d\n", tx_freef);
 }
+
+_public_
+int knot_xdp_socket_stats(knot_xdp_socket_t *socket, knot_xdp_stats_t *stats)
+{
+	if (socket == NULL || stats == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	memset(stats, 0, sizeof(*stats));
+
+	stats->if_name = socket->iface->if_name;
+	stats->if_index = socket->iface->if_index;
+	stats->if_queue = socket->iface->if_queue;
+
+	struct xdp_statistics xdp_stats;
+	socklen_t optlen = sizeof(xdp_stats);
+
+	int fd = knot_xdp_socket_fd(socket);
+	int ret = getsockopt(fd, SOL_XDP, XDP_STATISTICS, &xdp_stats, &optlen);
+	if (ret != 0) {
+		return knot_map_errno();
+	} else if (optlen != sizeof(xdp_stats)) {
+		return KNOT_EINVAL;
+	}
+
+	size_t common_size = MIN(sizeof(xdp_stats), sizeof(stats->socket));
+	memcpy(&stats->socket, &xdp_stats, common_size);
+
+	stats->rings.tx_busy = socket->umem->ring_size - socket->umem->tx_free_count;
+	stats->rings.fq_fill = RING_BUSY(&socket->umem->fq);
+	stats->rings.rx_fill = RING_BUSY(&socket->rx);
+	stats->rings.tx_fill = RING_BUSY(&socket->tx);
+	stats->rings.cq_fill = RING_BUSY(&socket->umem->cq);
+
+	return KNOT_EOK;
+}
diff --git a/src/libknot/xdp/xdp.h b/src/libknot/xdp/xdp.h
index cddb3ae572..70a5045528 100644
--- a/src/libknot/xdp/xdp.h
+++ b/src/libknot/xdp/xdp.h
@@ -1,4 +1,4 @@
-/*  Copyright (C) 2023 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+/*  Copyright (C) 2024 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -60,6 +60,44 @@ struct knot_xdp_config {
 /*! \brief Configuration of XDP socket. */
 typedef struct knot_xdp_config knot_xdp_config_t;
 
+/*! \brief Various statistics of an XDP socket (optimally kernel >=5.9). */
+typedef struct {
+	/*! Interface name. */
+	const char *if_name;
+	/*! Interface name index (derived from ifname). */
+	int if_index;
+	/*! Network card queue id. */
+	unsigned if_queue;
+	/*! Counters (xdp_statistics) retrieved from the kernel via XDP_STATISTICS. */
+	struct {
+		/*! Dropped for other reasons. */
+		uint64_t rx_dropped;
+		/*! Dropped due to invalid descriptor. */
+		uint64_t rx_invalid;
+		/*! Dropped due to invalid descriptor. */
+		uint64_t tx_invalid;
+		/*! Dropped due to rx ring being full. */
+		uint64_t rx_full;
+		/*! Failed to retrieve item from fill ring. */
+		uint64_t fq_empty;
+		/*! Failed to retrieve item from tx ring. */
+		uint64_t tx_empty;
+	} socket;
+	/*! States of rings of the XDP socket. */
+	struct {
+		/*! Busy TX buffers. */
+		uint16_t tx_busy;
+		/*! Free buffers to consume from FQ ring. */
+		uint16_t fq_fill;
+		/*! Pending buffers in TX ring. */
+		uint16_t rx_fill;
+		/*! Pending buffers in RX ring. */
+		uint16_t tx_fill;
+		/*! Pending buffers in CQ ring. */
+		uint16_t cq_fill;
+	} rings;
+} knot_xdp_stats_t;
+
 /*!
  * \brief Initialize XDP socket.
  *
@@ -195,4 +233,14 @@ void knot_xdp_recv_finish(knot_xdp_socket_t *socket, const knot_xdp_msg_t msgs[]
  */
 void knot_xdp_socket_info(const knot_xdp_socket_t *socket, FILE *file);
 
+/*!
+ * \brief Gets various statistics of the XDP socket.
+ *
+ * \param socket  XDP socket.
+ * \param stats   Output structure.
+ *
+ * \return KNOT_E*
+ */
+int knot_xdp_socket_stats(knot_xdp_socket_t *socket, knot_xdp_stats_t *stats);
+
 /*! @} */