Added support for IMIX through config and command line

In Prox configuration IMIX can be specified using the following syntax:
imix=pkt_size,pkt_size... Up to 127 different pkt sizes can be specified.

Through command line, the following syntax can be used
imix core_id task_id pkt_size,pkt_size... Up to 127 packet sizes can be specified.

When IMIX is enabled, PROX will loop through the list of packet sizes.

PROX supports two different submodes to handle pcap files.
In the 1st submode (default, no submode specified), timestamps from
the pcap file are ignored. In this submode IMIX is supported as well and each
packets in the pcap file will be generated with all IMIX sizes.

In the second submode, called pcap in gen mode, packets are generated at
the timestamp specified in the pcap file. This submode does not support IMIX.

Change-Id: I53cbf1378a5364254285b81e6848350d98561184
Signed-off-by: Xavier Simonart <xavier.simonart@intel.com>

1 files changed, 274 insertions, 121 deletions

diff --git a/VNFs/DPPD-PROX/handle_gen.c b/VNFs/DPPD-PROX/handle_gen.c
index 3bcb231f..1546dce7 100644
--- a/VNFs/DPPD-PROX/handle_gen.c
+++ b/VNFs/DPPD-PROX/handle_gen.c
@@ -22,6 +22,7 @@
 #include <rte_byteorder.h>
 #include <rte_ether.h>
 #include <rte_hash_crc.h>
+#include <rte_malloc.h>
 
 #include "prox_shared.h"
 #include "random.h"
@@ -56,6 +57,12 @@ struct pkt_template {
 
 #define IP4(x) x & 0xff, (x >> 8) & 0xff, (x >> 16) & 0xff, x >> 24
 
+#define DO_PANIC	1
+#define DO_NOT_PANIC	0
+
+#define FROM_PCAP	1
+#define NOT_FROM_PCAP	0
+
 #define TASK_OVERWRITE_SRC_MAC_WITH_PORT_MAC 1
 
 static void pkt_template_init_mbuf(struct pkt_template *pkt_template, struct rte_mbuf *mbuf, uint8_t *pkt)
@@ -78,6 +85,7 @@ struct task_gen_pcap {
 	uint32_t n_pkts;
 	uint64_t last_tsc;
 	uint64_t *proto_tsc;
+	uint32_t socket_id;
 };
 
 struct task_gen {
@@ -91,6 +99,7 @@ struct task_gen {
 	uint64_t new_rate_bps;
 	uint64_t pkt_queue_index;
 	uint32_t n_pkts; /* number of packets in pcap */
+	uint32_t orig_n_pkts; /* number of packets in pcap */
 	uint32_t pkt_idx; /* current packet from pcap */
 	uint32_t pkt_count; /* how many pakets to generate */
 	uint32_t max_frame_size;
@@ -100,6 +109,7 @@ struct task_gen {
 	uint16_t accur_pos;
 	uint16_t sig_pos;
 	uint32_t sig;
+	uint32_t socket_id;
 	uint8_t generator_id;
 	uint8_t n_rands; /* number of randoms */
 	uint8_t min_bulk_size;
@@ -121,6 +131,9 @@ struct task_gen {
 	uint8_t cksum_offload;
 	struct prox_port_cfg *port;
 	uint64_t *bytes_to_tsc;
+	uint32_t imix_pkt_sizes[MAX_IMIX_PKTS];
+	uint32_t imix_nb_pkts;
+	uint32_t new_imix_nb_pkts;
 } __rte_cache_aligned;
 
 static inline uint8_t ipv4_get_hdr_len(prox_rte_ipv4_hdr *ip)
@@ -266,7 +279,7 @@ static inline uint64_t bytes_to_tsc(struct task_gen *task, uint32_t bytes)
 
 static uint32_t task_gen_next_pkt_idx(const struct task_gen *task, uint32_t pkt_idx)
 {
-	return pkt_idx + 1 == task->n_pkts? 0 : pkt_idx + 1;
+	return pkt_idx + 1 >= task->n_pkts? 0 : pkt_idx + 1;
 }
 
 static uint32_t task_gen_offset_pkt_idx(const struct task_gen *task, uint32_t offset)
@@ -541,10 +554,196 @@ static void task_gen_build_packets(struct task_gen *task, struct rte_mbuf **mbuf
 	}
 }
 
+static int task_gen_allocate_templates(struct task_gen *task, uint32_t orig_nb_pkts, uint32_t nb_pkts, int do_panic, int pcap)
+{
+	size_t mem_size = nb_pkts * sizeof(*task->pkt_template);
+	size_t orig_mem_size = orig_nb_pkts * sizeof(*task->pkt_template);
+	task->pkt_template = prox_zmalloc(mem_size, task->socket_id);
+	task->pkt_template_orig = prox_zmalloc(orig_mem_size, task->socket_id);
+
+	if (task->pkt_template == NULL || task->pkt_template_orig == NULL) {
+		plog_err_or_panic(do_panic, "Failed to allocate %lu bytes (in huge pages) for %s\n", mem_size, pcap ? "pcap file":"packet template");
+		return -1;
+	}
+
+	for (size_t i = 0; i < orig_nb_pkts; i++) {
+		task->pkt_template_orig[i].buf = prox_zmalloc(task->max_frame_size, task->socket_id);
+		if (task->pkt_template_orig[i].buf == NULL) {
+			plog_err_or_panic(do_panic, "Failed to allocate %u bytes (in huge pages) for %s\n", task->max_frame_size, pcap ? "packet from pcap": "packet");
+			return -1;
+		}
+	}
+	for (size_t i = 0; i < nb_pkts; i++) {
+		task->pkt_template[i].buf = prox_zmalloc(task->max_frame_size, task->socket_id);
+		if (task->pkt_template[i].buf == NULL) {
+			plog_err_or_panic(do_panic, "Failed to allocate %u bytes (in huge pages) for %s\n", task->max_frame_size, pcap ? "packet from pcap": "packet");
+			return -1;
+		}
+	}
+	return 0;
+}
+
+static int task_gen_reallocate_templates(struct task_gen *task, uint32_t nb_pkts, int do_panic)
+{
+	// Need to free up bufs allocated in previous (longer) imix
+	for (size_t i = nb_pkts; i < task->n_pkts; i++) {
+		if (task->pkt_template[i].buf) {
+			rte_free(task->pkt_template[i].buf);
+			task->pkt_template[i].buf = NULL;
+		}
+	}
+
+	size_t mem_size = nb_pkts * sizeof(*task->pkt_template);
+	struct pkt_template *ptr;
+	// re-allocate memory for new pkt_template (this might allocate additional memory or free up some...)
+	if ((ptr = rte_realloc_socket(task->pkt_template, mem_size, RTE_CACHE_LINE_SIZE, task->socket_id)) != NULL) {
+		task->pkt_template = ptr;
+	} else {
+		plog_err_or_panic(do_panic, "Failed to allocate %lu bytes (in huge pages) for packet template for IMIX\n", mem_size);
+		return -1;
+	}
+
+	// Need to allocate bufs for new template but no need to reallocate for existing ones
+	for (size_t i = task->n_pkts; i < nb_pkts; ++i) {
+		task->pkt_template[i].buf = prox_zmalloc(task->max_frame_size, task->socket_id);
+		if (task->pkt_template[i].buf == NULL) {
+			plog_err_or_panic(do_panic, "Failed to allocate %u bytes (in huge pages) for packet %zd in IMIX\n", task->max_frame_size, i);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+static int check_pkt_size(struct task_gen *task, uint32_t pkt_size, int do_panic)
+{
+	const uint16_t min_len = sizeof(prox_rte_ether_hdr) + sizeof(prox_rte_ipv4_hdr);
+	const uint16_t max_len = task->max_frame_size;
+
+	if (do_panic) {
+		PROX_PANIC(pkt_size == 0, "Invalid packet size length (no packet defined?)\n");
+		PROX_PANIC(pkt_size > max_len, "pkt_size out of range (must be <= %u)\n", max_len);
+		PROX_PANIC(pkt_size < min_len, "pkt_size out of range (must be >= %u)\n", min_len);
+		return 0;
+	} else {
+		if (pkt_size == 0) {
+			plog_err("Invalid packet size length (no packet defined?)\n");
+			return -1;
+		}
+		if (pkt_size > max_len) {
+			if (pkt_size >  PROX_RTE_ETHER_MAX_LEN + 2 * PROX_VLAN_TAG_SIZE - 4)
+				plog_err("pkt_size too high and jumbo frames disabled\n");
+			else
+				plog_err("pkt_size out of range (must be <= (mtu=%u))\n", max_len);
+			return -1;
+		}
+		if (pkt_size < min_len) {
+			plog_err("pkt_size out of range (must be >= %u)\n", min_len);
+			return -1;
+		}
+		return 0;
+	}
+}
+
+static int check_fields_in_bounds(struct task_gen *task, uint32_t pkt_size, int do_panic)
+{
+	if (task->lat_enabled) {
+		uint32_t pos_beg = task->lat_pos;
+		uint32_t pos_end = task->lat_pos + 3U;
+
+		if (do_panic)
+			PROX_PANIC(pkt_size <= pos_end, "Writing latency at %u-%u, but packet size is %u bytes\n",
+			   pos_beg, pos_end, pkt_size);
+		else if (pkt_size <= pos_end) {
+			plog_err("Writing latency at %u-%u, but packet size is %u bytes\n", pos_beg, pos_end, pkt_size);
+			return -1;
+		}
+	}
+	if (task->packet_id_pos) {
+		uint32_t pos_beg = task->packet_id_pos;
+		uint32_t pos_end = task->packet_id_pos + 4U;
+
+		if (do_panic)
+			PROX_PANIC(pkt_size <= pos_end, "Writing packet at %u-%u, but packet size is %u bytes\n",
+			   pos_beg, pos_end, pkt_size);
+		else if (pkt_size <= pos_end) {
+			plog_err("Writing packet at %u-%u, but packet size is %u bytes\n", pos_beg, pos_end, pkt_size);
+			return -1;
+		}
+	}
+	if (task->accur_pos) {
+		uint32_t pos_beg = task->accur_pos;
+		uint32_t pos_end = task->accur_pos + 3U;
+
+		if (do_panic)
+			PROX_PANIC(pkt_size <= pos_end, "Writing accuracy at %u-%u, but packet size is %u bytes\n",
+			   pos_beg, pos_end, pkt_size);
+		else if (pkt_size <= pos_end) {
+			plog_err("Writing accuracy at %u-%u, but packet size is %u bytes\n", pos_beg, pos_end, pkt_size);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+static int task_gen_set_eth_ip_udp_sizes(struct task_gen *task, uint32_t n_orig_pkts, uint32_t nb_pkt_sizes, uint32_t *pkt_sizes)
+{
+	size_t k;
+	uint32_t l4_len;
+	prox_rte_ipv4_hdr *ip;
+	struct pkt_template *template;
+
+	for (size_t j = 0; j < nb_pkt_sizes; ++j) {
+		for (size_t i = 0; i < n_orig_pkts; ++i) {
+			k = j * n_orig_pkts + i;
+			template = &task->pkt_template[k];
+			template->len = pkt_sizes[j];
+       			rte_memcpy(template->buf, task->pkt_template_orig[i].buf, pkt_sizes[j]);
+			parse_l2_l3_len(template->buf, &template->l2_len, &template->l3_len, template->len);
+			if (template->l2_len == 0)
+				continue;
+			ip = (prox_rte_ipv4_hdr *)(template->buf + template->l2_len);
+			ip->total_length = rte_bswap16(pkt_sizes[j] - template->l2_len);
+			l4_len = pkt_sizes[j] - template->l2_len - template->l3_len;
+			ip->hdr_checksum = 0;
+			prox_ip_cksum_sw(ip);
+
+			if (ip->next_proto_id == IPPROTO_UDP) {
+				prox_rte_udp_hdr *udp = (prox_rte_udp_hdr *)(((uint8_t *)ip) + template->l3_len);
+				udp->dgram_len = rte_bswap16(l4_len);
+				prox_udp_cksum_sw(udp, l4_len, ip->src_addr, ip->dst_addr);
+			} else if (ip->next_proto_id == IPPROTO_TCP) {
+				prox_rte_tcp_hdr *tcp = (prox_rte_tcp_hdr *)(((uint8_t *)ip) + template->l3_len);
+				prox_tcp_cksum_sw(tcp, l4_len, ip->src_addr, ip->dst_addr);
+			}
+		}
+	}
+	return 0;
+}
+
+static int task_gen_apply_imix(struct task_gen *task, int do_panic)
+{
+	struct pkt_template *ptr;
+	int rc;
+	task->imix_nb_pkts = task->new_imix_nb_pkts;
+	uint32_t n_pkts = task->imix_nb_pkts * task->orig_n_pkts;
+
+	if ((n_pkts != task->n_pkts) && ((rc = task_gen_reallocate_templates(task, n_pkts, do_panic)) < 0))
+		return rc;
+
+	task->n_pkts = n_pkts;
+	if (task->pkt_idx >= n_pkts)
+		task->pkt_idx = 0;
+	task_gen_set_eth_ip_udp_sizes(task, task->orig_n_pkts, task->imix_nb_pkts, task->imix_pkt_sizes);
+	return 0;
+}
+
 static void task_gen_update_config(struct task_gen *task)
 {
 	if (task->token_time.cfg.bpp != task->new_rate_bps)
 		task_gen_reset_token_time(task);
+	if (task->new_imix_nb_pkts)
+		task_gen_apply_imix(task, DO_NOT_PANIC);
+	task->new_imix_nb_pkts = 0;
 }
 
 static inline void build_value(struct task_gen *task, uint32_t mask, int bit_pos, uint32_t val, uint32_t fixed_bits)
@@ -759,33 +958,6 @@ static int pcap_read_pkts(pcap_t *handle, const char *file_name, uint32_t n_pkts
 	return 0;
 }
 
-static int check_pkt_size(struct task_gen *task, uint32_t pkt_size, int do_panic)
-{
-	const uint16_t min_len = sizeof(prox_rte_ether_hdr) + sizeof(prox_rte_ipv4_hdr);
-	const uint16_t max_len = task->max_frame_size;
-
-	if (do_panic) {
-		PROX_PANIC(pkt_size == 0, "Invalid packet size length (no packet defined?)\n");
-		PROX_PANIC(pkt_size > max_len, "pkt_size out of range (must be <= %u)\n", max_len);
-		PROX_PANIC(pkt_size < min_len, "pkt_size out of range (must be >= %u)\n", min_len);
-		return 0;
-	} else {
-		if (pkt_size == 0) {
-			plog_err("Invalid packet size length (no packet defined?)\n");
-			return -1;
-		}
-		if (pkt_size > max_len) {
-			plog_err("pkt_size out of range (must be <= %u)\n", max_len);
-			return -1;
-		}
-		if (pkt_size < min_len) {
-			plog_err("pkt_size out of range (must be >= %u)\n", min_len);
-			return -1;
-		}
-		return 0;
-	}
-}
-
 static int check_all_pkt_size(struct task_gen *task, int do_panic)
 {
 	int rc;
@@ -796,43 +968,12 @@ static int check_all_pkt_size(struct task_gen *task, int do_panic)
 	return 0;
 }
 
-static int check_fields_in_bounds(struct task_gen *task, uint32_t pkt_size, int do_panic)
+static int check_all_fields_in_bounds(struct task_gen *task, int do_panic)
 {
-	if (task->lat_enabled) {
-		uint32_t pos_beg = task->lat_pos;
-		uint32_t pos_end = task->lat_pos + 3U;
-
-		if (do_panic)
-			PROX_PANIC(pkt_size <= pos_end, "Writing latency at %u-%u, but packet size is %u bytes\n",
-			   pos_beg, pos_end, pkt_size);
-		else if (pkt_size <= pos_end) {
-			plog_err("Writing latency at %u-%u, but packet size is %u bytes\n", pos_beg, pos_end, pkt_size);
-			return -1;
-		}
-	}
-	if (task->packet_id_pos) {
-		uint32_t pos_beg = task->packet_id_pos;
-		uint32_t pos_end = task->packet_id_pos + 4U;
-
-		if (do_panic)
-			PROX_PANIC(pkt_size <= pos_end, "Writing packet at %u-%u, but packet size is %u bytes\n",
-			   pos_beg, pos_end, pkt_size);
-		else if (pkt_size <= pos_end) {
-			plog_err("Writing packet at %u-%u, but packet size is %u bytes\n", pos_beg, pos_end, pkt_size);
-			return -1;
-		}
-	}
-	if (task->accur_pos) {
-		uint32_t pos_beg = task->accur_pos;
-		uint32_t pos_end = task->accur_pos + 3U;
-
-		if (do_panic)
-			PROX_PANIC(pkt_size <= pos_end, "Writing accuracy at %u%-u, but packet size is %u bytes\n",
-			   pos_beg, pos_end, pkt_size);
-		else if (pkt_size <= pos_end) {
-			plog_err("Writing accuracy at %u%-u, but packet size is %u bytes\n", pos_beg, pos_end, pkt_size);
-			return -1;
-		}
+	int rc;
+	for (uint32_t i = 0; i < task->n_pkts;++i) {
+		if ((rc = check_fields_in_bounds(task, task->pkt_template[i].len, do_panic)) != 0)
+			return rc;
 	}
 	return 0;
 }
@@ -894,10 +1035,12 @@ static void task_gen_reset_pkt_templates_len(struct task_gen *task)
 {
 	struct pkt_template *src, *dst;
 
-	for (size_t i = 0; i < task->n_pkts; ++i) {
-		src = &task->pkt_template_orig[i];
-		dst = &task->pkt_template[i];
-		dst->len = src->len;
+	for (size_t j = 0; j < task->n_pkts / task->orig_n_pkts; ++j) {
+		for (size_t i = 0; i < task->orig_n_pkts; ++i) {
+			src = &task->pkt_template_orig[i];
+			dst = &task->pkt_template[j * task->orig_n_pkts + i];
+			dst->len = src->len;
+		}
 	}
 }
 
@@ -905,11 +1048,13 @@ static void task_gen_reset_pkt_templates_content(struct task_gen *task)
 {
 	struct pkt_template *src, *dst;
 
-	for (size_t i = 0; i < task->n_pkts; ++i) {
-		src = &task->pkt_template_orig[i];
-		dst = &task->pkt_template[i];
-		memcpy(dst->buf, src->buf, RTE_MAX(src->len, dst->len));
-		task_gen_apply_sig(task, dst);
+	for (size_t j = 0; j < task->n_pkts / task->orig_n_pkts; ++j) {
+		for (size_t i = 0; i < task->orig_n_pkts; ++i) {
+			src = &task->pkt_template_orig[i];
+			dst = &task->pkt_template[j * task->orig_n_pkts + i];
+			memcpy(dst->buf, src->buf, RTE_MAX(src->len, dst->len));
+			task_gen_apply_sig(task, dst);
+		}
 	}
 }
 
@@ -922,71 +1067,57 @@ static void task_gen_reset_pkt_templates(struct task_gen *task)
 
 static void task_init_gen_load_pkt_inline(struct task_gen *task, struct task_args *targ)
 {
-	const int socket_id = rte_lcore_to_socket_id(targ->lconf->id);
-
-	task->n_pkts = 1;
-
-	size_t mem_size = task->n_pkts * sizeof(*task->pkt_template);
-	task->pkt_template = prox_zmalloc(mem_size, socket_id);
-	task->pkt_template_orig = prox_zmalloc(mem_size, socket_id);
-
-	PROX_PANIC(task->pkt_template == NULL ||
-		   task->pkt_template_orig == NULL,
-		   "Failed to allocate %lu bytes (in huge pages) for packet template\n", mem_size);
-
-	task->pkt_template->buf = prox_zmalloc(task->max_frame_size, socket_id);
-	task->pkt_template_orig->buf = prox_zmalloc(task->max_frame_size, socket_id);
-	PROX_PANIC(task->pkt_template->buf == NULL ||
-		task->pkt_template_orig->buf == NULL,
-		"Failed to allocate %u bytes (in huge pages) for packet\n", task->max_frame_size);
+	int rc;
 
-	PROX_PANIC(targ->pkt_size > task->max_frame_size,
-		targ->pkt_size > PROX_RTE_ETHER_MAX_LEN + 2 * PROX_VLAN_TAG_SIZE - 4 ?
-			"pkt_size too high and jumbo frames disabled" : "pkt_size > mtu");
+	task->orig_n_pkts = 1;
+	if (task->imix_nb_pkts == 0) {
+		task->n_pkts = 1;
+		task->imix_pkt_sizes[0] = targ->pkt_size;
+	} else {
+		task->n_pkts = task->imix_nb_pkts;
+	}
+	task_gen_allocate_templates(task, task->orig_n_pkts, task->n_pkts, DO_PANIC, NOT_FROM_PCAP);
 
-	rte_memcpy(task->pkt_template_orig[0].buf, targ->pkt_inline, targ->pkt_size);
-	task->pkt_template_orig[0].len = targ->pkt_size;
+	rte_memcpy(task->pkt_template_orig[0].buf, targ->pkt_inline, task->max_frame_size);
+	task->pkt_template_orig[0].len = task->imix_pkt_sizes[0];
 	task_gen_reset_pkt_templates(task);
-	check_all_pkt_size(task, 1);
-	check_fields_in_bounds(task, task->pkt_template[0].len, 1);
+	check_all_pkt_size(task, DO_PANIC);
+	check_all_fields_in_bounds(task, DO_PANIC);
+
+	// If IMIX was not specified then pkt_size is specified using pkt_size parameter or the length of pkt_inline
+	// In that case, for backward compatibility, we do NOT adapt the length of IP and UDP to the length of the packet
+	task_gen_set_eth_ip_udp_sizes(task, task->orig_n_pkts, task->imix_nb_pkts, task->imix_pkt_sizes);
 }
 
 static void task_init_gen_load_pcap(struct task_gen *task, struct task_args *targ)
 {
-	const int socket_id = rte_lcore_to_socket_id(targ->lconf->id);
 	char err[PCAP_ERRBUF_SIZE];
 	uint32_t max_frame_size;
 	pcap_t *handle = pcap_open_offline(targ->pcap_file, err);
 	PROX_PANIC(handle == NULL, "Failed to open PCAP file: %s\n", err);
 
-	task->n_pkts = pcap_count_pkts(handle, &max_frame_size);
-	plogx_info("%u packets in pcap file '%s'; max frame size=%d\n", task->n_pkts, targ->pcap_file, max_frame_size);
+	task->orig_n_pkts = pcap_count_pkts(handle, &max_frame_size);
+	plogx_info("%u packets in pcap file '%s'; max frame size=%d\n", task->orig_n_pkts, targ->pcap_file, max_frame_size);
 	PROX_PANIC(max_frame_size > task->max_frame_size,
 		max_frame_size > PROX_RTE_ETHER_MAX_LEN + 2 * PROX_VLAN_TAG_SIZE -4 ?
 			"pkt_size too high and jumbo frames disabled" : "pkt_size > mtu");
 
 	if (targ->n_pkts)
-		task->n_pkts = RTE_MIN(task->n_pkts, targ->n_pkts);
-	plogx_info("Loading %u packets from pcap\n", task->n_pkts);
-	size_t mem_size = task->n_pkts * sizeof(*task->pkt_template);
-	task->pkt_template = prox_zmalloc(mem_size, socket_id);
-	task->pkt_template_orig = prox_zmalloc(mem_size, socket_id);
-	PROX_PANIC(task->pkt_template == NULL ||
-		   task->pkt_template_orig == NULL,
-		   "Failed to allocate %lu bytes (in huge pages) for pcap file\n", mem_size);
-
-	for (uint i = 0; i < task->n_pkts; i++) {
-		task->pkt_template[i].buf = prox_zmalloc(task->max_frame_size, socket_id);
-		task->pkt_template_orig[i].buf = prox_zmalloc(task->max_frame_size, socket_id);
-
-		PROX_PANIC(task->pkt_template->buf == NULL ||
-			task->pkt_template_orig->buf == NULL,
-			"Failed to allocate %u bytes (in huge pages) for pcap file\n", task->max_frame_size);
+		task->orig_n_pkts = RTE_MIN(task->orig_n_pkts, targ->n_pkts);
+	if (task->imix_nb_pkts == 0) {
+		task->n_pkts = task->orig_n_pkts;
+	} else {
+		task->n_pkts = task->imix_nb_pkts * task->orig_n_pkts;
 	}
+	task_gen_allocate_templates(task, task->orig_n_pkts, task->n_pkts, DO_PANIC, FROM_PCAP);
+	plogx_info("Loading %u packets from pcap\n", task->n_pkts);
 
-	pcap_read_pkts(handle, targ->pcap_file, task->n_pkts, task->pkt_template_orig, NULL, max_frame_size);
+	pcap_read_pkts(handle, targ->pcap_file, task->orig_n_pkts, task->pkt_template_orig, NULL, max_frame_size);
 	pcap_close(handle);
 	task_gen_reset_pkt_templates(task);
+	check_all_pkt_size(task, DO_PANIC);
+	check_all_fields_in_bounds(task, DO_PANIC);
+	task_gen_set_eth_ip_udp_sizes(task, task->orig_n_pkts, task->imix_nb_pkts, task->imix_pkt_sizes);
 }
 
 static struct rte_mempool *task_gen_create_mempool(struct task_args *targ, uint16_t max_frame_size)
@@ -1037,6 +1168,23 @@ int task_gen_set_pkt_size(struct task_base *tbase, uint32_t pkt_size)
 	return 0;
 }
 
+int task_gen_set_imix(struct task_base *tbase, uint32_t nb_pkt_sizes, uint32_t *pkt_sizes)
+{
+	struct task_gen *task = (struct task_gen *)tbase;
+	int rc;
+
+	memcpy(task->imix_pkt_sizes, pkt_sizes, nb_pkt_sizes * sizeof(uint32_t));
+	for (size_t i = 0; i < nb_pkt_sizes; ++i) {
+		if ((rc = check_pkt_size(task, pkt_sizes[i], DO_NOT_PANIC)) != 0)
+			return rc;
+		if ((rc = check_fields_in_bounds(task, pkt_sizes[i], DO_NOT_PANIC)) != 0)
+			return rc;
+	}
+	// only set new_imix_nb_pkts if checks of pkt sizes succeeded
+	task->new_imix_nb_pkts = nb_pkt_sizes;
+	return 0;
+}
+
 void task_gen_set_rate(struct task_base *tbase, uint64_t bps)
 {
 	struct task_gen *task = (struct task_gen *)tbase;
@@ -1096,7 +1244,7 @@ uint32_t task_gen_get_n_randoms(struct task_base *tbase)
 static void init_task_gen_pcap(struct task_base *tbase, struct task_args *targ)
 {
 	struct task_gen_pcap *task = (struct task_gen_pcap *)tbase;
-	const uint32_t sockid = rte_lcore_to_socket_id(targ->lconf->id);
+	task->socket_id = rte_lcore_to_socket_id(targ->lconf->id);
 	uint32_t max_frame_size;
 
 	task->loop = targ->loop;
@@ -1122,14 +1270,14 @@ static void init_task_gen_pcap(struct task_base *tbase, struct task_args *targ)
 	plogx_info("Loading %u packets from pcap\n", task->n_pkts);
 
 	size_t mem_size = task->n_pkts * (sizeof(*task->proto) + sizeof(*task->proto_tsc));
-	uint8_t *mem = prox_zmalloc(mem_size, sockid);
+	uint8_t *mem = prox_zmalloc(mem_size, task->socket_id);
 
 	PROX_PANIC(mem == NULL, "Failed to allocate %lu bytes (in huge pages) for pcap file\n", mem_size);
 	task->proto = (struct pkt_template *) mem;
 	task->proto_tsc = (uint64_t *)(mem + task->n_pkts * sizeof(*task->proto));
 
 	for (uint i = 0; i < targ->n_pkts; i++) {
-		task->proto[i].buf = prox_zmalloc(max_frame_size, sockid);
+		task->proto[i].buf = prox_zmalloc(max_frame_size, task->socket_id);
 		PROX_PANIC(task->proto[i].buf == NULL, "Failed to allocate %u bytes (in huge pages) for pcap file\n", max_frame_size);
 	}
 
@@ -1229,6 +1377,7 @@ static void init_task_gen_early(struct task_args *targ)
 static void init_task_gen(struct task_base *tbase, struct task_args *targ)
 {
 	struct task_gen *task = (struct task_gen *)tbase;
+	task->socket_id = rte_lcore_to_socket_id(targ->lconf->id);
 
 	task->packet_id_pos = targ->packet_id_pos;
 
@@ -1282,7 +1431,7 @@ static void init_task_gen(struct task_base *tbase, struct task_args *targ)
 	plog_info("\tGenerator id = %d\n", task->generator_id);
 
 	// Allocate array holding bytes to tsc for supported frame sizes
-	task->bytes_to_tsc = prox_zmalloc(task->max_frame_size * MAX_PKT_BURST * sizeof(task->bytes_to_tsc[0]), rte_lcore_to_socket_id(targ->lconf->id));
+	task->bytes_to_tsc = prox_zmalloc(task->max_frame_size * MAX_PKT_BURST * sizeof(task->bytes_to_tsc[0]), task->socket_id);
 	PROX_PANIC(task->bytes_to_tsc == NULL,
 		"Failed to allocate %u bytes (in huge pages) for bytes_to_tsc\n", task->max_frame_size);
 
@@ -1304,6 +1453,10 @@ static void init_task_gen(struct task_base *tbase, struct task_args *targ)
 			task->bytes_to_tsc[i] = (task->hz * i * 0.99) / bytes_per_hz;
 	}
 
+	task->imix_nb_pkts = targ->imix_nb_pkts;
+	for (uint32_t i = 0; i < targ->imix_nb_pkts; i++) {
+		task->imix_pkt_sizes[i] = targ->imix_pkt_sizes[i];
+	}
 	if (!strcmp(targ->pcap_file, "")) {
 		plog_info("\tUsing inline definition of a packet\n");
 		task_init_gen_load_pkt_inline(task, targ);