/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright(c) 2018 Red Hat Corp.
 */

#include <stdarg.h>
#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <errno.h>
#include <stdint.h>
#include <unistd.h>
#include <inttypes.h>

#include <sys/queue.h>
#include <sys/stat.h>

#include <rte_common.h>
#include <rte_log.h>
#include <rte_debug.h>
#include <rte_cycles.h>
#include <rte_memory.h>
#include <rte_launch.h>
#include <rte_eal.h>
#include <rte_per_lcore.h>
#include <rte_lcore.h>
#include <rte_memcpy.h>
#include <rte_mempool.h>
#include <rte_mbuf.h>
#include <rte_ethdev.h>
#include <rte_flow.h>
#include <rte_malloc.h>

#include "testpmd.h"

struct noisy_config {
	struct rte_ring *f;
	uint64_t prev_time;
	char *vnf_mem;
	bool do_buffering;
	bool do_flush;
	bool do_sim;
};

struct noisy_config *noisy_cfg[RTE_MAX_ETHPORTS];

static inline void
do_write(char *vnf_mem)
{
	uint64_t i = rte_rand();
	uint64_t w = rte_rand();

	vnf_mem[i % ((noisy_lkup_mem_sz * 1024 * 1024) /
			RTE_CACHE_LINE_SIZE)] = w;
}

static inline void
do_read(char *vnf_mem)
{
	uint64_t i = rte_rand();
	uint64_t r;

	r = vnf_mem[i % ((noisy_lkup_mem_sz * 1024 * 1024) /
			RTE_CACHE_LINE_SIZE)];
	r++;
}

static inline void
do_readwrite(char *vnf_mem)
{
	do_read(vnf_mem);
	do_write(vnf_mem);
}

/*
 * Simulate route lookups as defined by commandline parameters
 */
static void
sim_memory_lookups(struct noisy_config *ncf, uint16_t nb_pkts)
{
	uint16_t i, j;

	if (!ncf->do_sim)
		return;

	for (i = 0; i < nb_pkts; i++) {
		for (j = 0; j < noisy_lkup_num_writes; j++)
			do_write(ncf->vnf_mem);
		for (j = 0; j < noisy_lkup_num_reads; j++)
			do_read(ncf->vnf_mem);
		for (j = 0; j < noisy_lkup_num_reads_writes; j++)
			do_readwrite(ncf->vnf_mem);
	}
}

static uint16_t
do_retry(uint16_t nb_rx, uint16_t nb_tx, struct rte_mbuf **pkts,
	 struct fwd_stream *fs)
{
	uint32_t retry = 0;

	while (nb_tx < nb_rx && retry++ < burst_tx_retry_num) {
		rte_delay_us(burst_tx_delay_time);
		nb_tx += rte_eth_tx_burst(fs->tx_port, fs->tx_queue,
				&pkts[nb_tx], nb_rx - nb_tx);
	}

	return nb_tx;
}

static uint32_t
drop_pkts(struct rte_mbuf **pkts, uint16_t nb_rx, uint16_t nb_tx)
{
	if (nb_tx < nb_rx) {
		do {
			rte_pktmbuf_free(pkts[nb_tx]);
		} while (++nb_tx < nb_rx);
	}

	return nb_rx - nb_tx;
}

/*
 * Forwarding of packets in noisy VNF mode.  Forward packets but perform
 * memory operations first as specified on cmdline.
 *
 * Depending on which commandline parameters are specified we have
 * different cases to handle:
 *
 * 1. No FIFO size was given, so we don't do buffering of incoming
 *    packets.  This case is pretty much what iofwd does but in this case
 *    we also do simulation of memory accesses (depending on which
 *    parameters were specified for it).
 * 2. User wants do buffer packets in a FIFO and sent out overflowing
 *    packets.
 * 3. User wants a FIFO and specifies a time in ms to flush all packets
 *    out of the FIFO
 * 4. Cases 2 and 3 combined
 */
static void
pkt_burst_noisy_vnf(struct fwd_stream *fs)
{
	const uint64_t freq_khz = rte_get_timer_hz() / 1000;
	struct noisy_config *ncf = noisy_cfg[fs->rx_port];
	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
	struct rte_mbuf *tmp_pkts[MAX_PKT_BURST];
	uint16_t nb_deqd = 0;
	uint16_t nb_rx = 0;
	uint16_t nb_tx = 0;
	uint16_t nb_enqd;
	unsigned int fifo_free;
	uint64_t delta_ms;
	bool needs_flush = false;
	uint64_t now;

	nb_rx = rte_eth_rx_burst(fs->rx_port, fs->rx_queue,
			pkts_burst, nb_pkt_per_burst);
	if (unlikely(nb_rx == 0))
		goto flush;
	fs->rx_packets += nb_rx;

	if (!ncf->do_buffering) {
		sim_memory_lookups(ncf, nb_rx);
		nb_tx = rte_eth_tx_burst(fs->tx_port, fs->tx_queue,
				pkts_burst, nb_rx);
		if (unlikely(nb_tx < nb_rx) && fs->retry_enabled)
			nb_tx += do_retry(nb_rx, nb_tx, pkts_burst, fs);
		fs->tx_packets += nb_tx;
		fs->fwd_dropped += drop_pkts(pkts_burst, nb_rx, nb_tx);
		return;
	}

	fifo_free = rte_ring_free_count(ncf->f);
	if (fifo_free >= nb_rx) {
		nb_enqd = rte_ring_enqueue_burst(ncf->f,
				(void **) pkts_burst, nb_rx, NULL);
		if (nb_enqd < nb_rx)
			fs->fwd_dropped += drop_pkts(pkts_burst,
						     nb_rx, nb_enqd);
	} else {
		nb_deqd = rte_ring_dequeue_burst(ncf->f,
				(void **) tmp_pkts, nb_rx, NULL);
		nb_enqd = rte_ring_enqueue_burst(ncf->f,
				(void **) pkts_burst, nb_deqd, NULL);
		if (nb_deqd > 0) {
			nb_tx = rte_eth_tx_burst(fs->tx_port,
					fs->tx_queue, tmp_pkts,
					nb_deqd);
			if (unlikely(nb_tx < nb_rx) && fs->retry_enabled)
				nb_tx += do_retry(nb_rx, nb_tx, tmp_pkts, fs);
			fs->fwd_dropped += drop_pkts(tmp_pkts, nb_deqd, nb_tx);
		}
	}

	sim_memory_lookups(ncf, nb_enqd);

flush:
	if (ncf->do_flush) {
		if (!ncf->prev_time)
			now = ncf->prev_time = rte_get_timer_cycles();
		else
			now = rte_get_timer_cycles();
		delta_ms = (now - ncf->prev_time) / freq_khz;
		needs_flush = delta_ms >= noisy_tx_sw_buf_flush_time &&
				noisy_tx_sw_buf_flush_time > 0 && !nb_tx;
	}
	while (needs_flush && !rte_ring_empty(ncf->f)) {
		unsigned int sent;
		nb_deqd = rte_ring_dequeue_burst(ncf->f, (void **)tmp_pkts,
				MAX_PKT_BURST, NULL);
		sent = rte_eth_tx_burst(fs->tx_port, fs->tx_queue,
					 tmp_pkts, nb_deqd);
		if (unlikely(sent < nb_deqd) && fs->retry_enabled)
			nb_tx += do_retry(nb_rx, nb_tx, tmp_pkts, fs);
		fs->fwd_dropped += drop_pkts(tmp_pkts, nb_deqd, sent);
		ncf->prev_time = rte_get_timer_cycles();
	}
}

#define NOISY_STRSIZE 256
#define NOISY_RING "noisy_ring_%d\n"

static void
noisy_fwd_end(portid_t pi)
{
	rte_ring_free(noisy_cfg[pi]->f);
	rte_free(noisy_cfg[pi]->vnf_mem);
	rte_free(noisy_cfg[pi]);
}

static void
noisy_fwd_begin(portid_t pi)
{
	struct noisy_config *n;
	char name[NOISY_STRSIZE];

	noisy_cfg[pi] = rte_zmalloc("testpmd noisy fifo and timers",
				sizeof(struct noisy_config),
				RTE_CACHE_LINE_SIZE);
	if (noisy_cfg[pi] == NULL) {
		rte_exit(EXIT_FAILURE,
			 "rte_zmalloc(%d) struct noisy_config) failed\n",
			 (int) pi);
	}
	n = noisy_cfg[pi];
	n->do_buffering = noisy_tx_sw_bufsz > 0;
	n->do_sim = noisy_lkup_num_writes + noisy_lkup_num_reads +
		    noisy_lkup_num_reads_writes;
	n->do_flush = noisy_tx_sw_buf_flush_time > 0;

	if (n->do_buffering) {
		snprintf(name, NOISY_STRSIZE, NOISY_RING, pi);
		n->f = rte_ring_create(name, noisy_tx_sw_bufsz,
				rte_socket_id(), 0);
		if (!n->f)
			rte_exit(EXIT_FAILURE,
				 "rte_ring_create(%d), size %d) failed\n",
				 (int) pi,
				 noisy_tx_sw_bufsz);
	}
	if (noisy_lkup_mem_sz > 0) {
		n->vnf_mem = (char *) rte_zmalloc("vnf sim memory",
				 noisy_lkup_mem_sz * 1024 * 1024,
				 RTE_CACHE_LINE_SIZE);
		if (!n->vnf_mem)
			rte_exit(EXIT_FAILURE,
			   "rte_zmalloc(%" PRIu64 ") for vnf memory) failed\n",
			   noisy_lkup_mem_sz);
	} else if (n->do_sim) {
		rte_exit(EXIT_FAILURE,
			 "--noisy-lkup-memory-size must be > 0\n");
	}
}

struct fwd_engine noisy_vnf_engine = {
	.fwd_mode_name  = "noisy",
	.port_fwd_begin = noisy_fwd_begin,
	.port_fwd_end   = noisy_fwd_end,
	.packet_fwd     = pkt_burst_noisy_vnf,
};