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openairinterface5g/radio/ETHERNET/eth_udp.c
Robert Schmidt 6d75ca8e9c Move fhstate into eth structure 
fhstate is only used in the ETHERNET library, so move it to a smaller
scope. In AW2S it is write-only, so we can remove it.

Signed-off-by: Robert Schmidt <robert.schmidt@openairinterface.org>
2026-07-02 08:46:09 +02:00

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/*
* SPDX-License-Identifier: LicenseRef-CSSL-1.0
*/
/*!
* \brief API to stream I/Q samples over standard ethernet
*/
// _GNU_SOURCE needed to have sched_getcpu() from sched.h
#define _GNU_SOURCE
#include <arpa/inet.h>
#include <linux/if_packet.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <linux/filter.h>
#include <net/if.h>
#include <netinet/ether.h>
#include <unistd.h>
#include <errno.h>
#include <sched.h>
#include "common_lib.h"
#include "ethernet_lib.h"
#include "openair1/PHY/sse_intrin.h"
//#define DEBUG 1
// These are for IF5 and must be put into the device structure if multiple RUs in the same RAU !!!!!!!!!!!!!!!!!
uint16_t pck_seq_num = 1;
uint16_t pck_seq_num_cur=0;
uint16_t pck_seq_num_prev=0;
int eth_socket_init_udp(openair0_device_t *device)
{
eth_state_t *eth = (eth_state_t*)device->priv;
eth_params_t *eth_params = device->eth_params;
char str_local[INET_ADDRSTRLEN];
char str_remote[INET_ADDRSTRLEN];
const char *local_ip, *remote_ipc,*remote_ipd;
int local_portc=0,local_portd=0, remote_portc=0,remote_portd=0;
int sock_dom=0;
int sock_type=0;
int sock_proto=0;
int enable=1;
const char str[2][4] = {"RRU\0","RAU\0"};
int hostind = 0;
local_ip = eth_params->my_addr;
local_portc = eth_params->my_portc;
local_portd = eth_params->my_portd;
if (device->host_type == RRU_HOST ) {
remote_ipc = "0.0.0.0";
remote_ipd = eth_params->remote_addr;
remote_portc = 0;
remote_portd = eth_params->remote_portd;;
printf("[%s] local ip addr %s portc %d portd %d\n", "RRU", local_ip, local_portc, local_portd);
} else {
remote_ipc = eth_params->remote_addr;
remote_ipd = "0.0.0.0";
remote_portc = eth_params->remote_portc;
remote_portd = 0;
hostind = 1;
printf("[%s] local ip addr %s portc %d portd %d\n","RAU", local_ip, local_portc, local_portd);
}
/* Open socket to send on */
sock_dom=AF_INET;
sock_type=SOCK_DGRAM;
sock_proto=IPPROTO_UDP;
if ((eth->sockfdc = socket(sock_dom, sock_type, sock_proto)) == -1) {
perror("ETHERNET: Error opening socket (control)");
exit(0);
}
for (int i = 0;i<eth->num_fd;i++)
if ((eth->sockfdd[i] = socket(sock_dom, sock_type, sock_proto)) == -1) {
printf("ETHERNET: Error opening socket (user %d)",i);
exit(0);
}
/* initialize addresses */
bzero((void *)&(eth->dest_addrc), sizeof(eth->dest_addrc));
bzero((void *)&(eth->local_addrc), sizeof(eth->local_addrc));
bzero((void *)&(eth->dest_addrd), sizeof(eth->dest_addrd));
bzero((void *)&(eth->local_addrd), sizeof(eth->local_addrd));
eth->addr_len = sizeof(struct sockaddr_in);
eth->dest_addrc.sin_family = AF_INET;
inet_pton(AF_INET,remote_ipc,&(eth->dest_addrc.sin_addr.s_addr));
eth->dest_addrc.sin_port=htons(remote_portc);
inet_ntop(AF_INET, &(eth->dest_addrc.sin_addr), str_remote, INET_ADDRSTRLEN);
eth->dest_addrd.sin_family = AF_INET;
inet_pton(AF_INET,remote_ipd,&(eth->dest_addrd.sin_addr.s_addr));
eth->dest_addrd.sin_port=htons(remote_portd);
eth->local_addrc.sin_family = AF_INET;
inet_pton(AF_INET,local_ip,&(eth->local_addrc.sin_addr.s_addr));
eth->local_addrc.sin_port=htons(local_portc);
inet_ntop(AF_INET, &(eth->local_addrc.sin_addr), str_local, INET_ADDRSTRLEN);
eth->local_addrd.sin_family = AF_INET;
inet_pton(AF_INET,local_ip,&(eth->local_addrd.sin_addr.s_addr));
eth->local_addrd.sin_port=htons(local_portd);
/* set reuse address flag */
if (setsockopt(eth->sockfdc, SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(int))) {
perror("ETHERNET: Cannot set SO_REUSEADDR option on socket (control)");
exit(0);
}
for (int i=0;i<eth->num_fd;i++) {
if (setsockopt(eth->sockfdd[i], SOL_SOCKET, SO_NO_CHECK, &enable, sizeof(int))) {
printf("ETHERNET: Cannot set SO_NO_CHECK option on socket (user %d)",i);
exit(0);
}
#if 0 /*def SO_ATTACH_REUSEPORT_EBPF*/
if (setsockopt(eth->sockfdd[i], SOL_SOCKET, SO_REUSEPORT, &enable, sizeof(int))) {
printf("ETHERNET: Cannot set SO_REUSEPORT option on socket (user %d)",i);
exit(0);
}
struct sock_filter code[]={
{ BPF_LD | BPF_W | BPF_ABS, 0, 0, SKF_AD_OFF + SKF_AD_CPU }, // A = #cpu
{ BPF_RET | BPF_A, 0, 0, 0 }, // return A
};
struct sock_fprog bpf = {
.len = sizeof(code)/sizeof(struct sock_filter),
.filter = code,
};
if (i==0 && setsockopt(eth->sockfdd[i], SOL_SOCKET, SO_ATTACH_REUSEPORT_CBPF, &bpf, sizeof(bpf))) {
printf("ETHERNET: Cannot set SO_ATTACH_REUSEPORT_EBPF option on socket (user %d)",i);
exit(0);
}
else printf("ETHERNET: set SO_ATTACH_REUSEPORT_EBPF option on socket (user %d)\n",i);
#endif
}
/* want to receive -> so bind */
if (bind(eth->sockfdc,(struct sockaddr *)&eth->local_addrc,eth->addr_len)<0) {
perror("ETHERNET: Cannot bind to socket (control)");
exit(0);
} else {
printf("[%s] binding to %s:%d (control)\n",str[hostind],str_local,ntohs(eth->local_addrc.sin_port));
}
for (int i=0;i<eth->num_fd;i++)
if (bind(eth->sockfdd[i],(struct sockaddr *)&eth->local_addrd,eth->addr_len)<0) {
printf("ETHERNET: Cannot bind to socket (user %d)",i);
exit(0);
} else {
printf("[%s] binding to %s:%d (user %d)\n",str[hostind],str_local,ntohs(eth->local_addrd.sin_port),i);
}
return 0;
}
int trx_eth_read_udp_IF4p5(openair0_device_t *device, openair0_timestamp_t *timestamp, void **buff, int nsamps, int cc)
{
// Read nblocks info from packet itself
int nblocks = nsamps;
int bytes_received=-1;
eth_state_t *eth = (eth_state_t*)device->priv;
ssize_t packet_size = sizeof_IF4p5_header_t;
IF4p5_header_t *test_header = (IF4p5_header_t*)(buff[0]);
int block_cnt=0;
// *2 because of 2 antennas PUL/DLFFT are controlled by nsamps, PRACH is not
packet_size = max(UDP_IF4p5_PRACH_SIZE_BYTES*2, max(UDP_IF4p5_PULFFT_SIZE_BYTES(nblocks), UDP_IF4p5_PDLFFT_SIZE_BYTES(nblocks)));
while(bytes_received == -1) {
again:
bytes_received = recvfrom(eth->sockfdd[0/*cc%eth->num_fd*/],
buff[0],
packet_size,
0,
(struct sockaddr *)&eth->dest_addrd,
(socklen_t *)&eth->addr_len);
if (bytes_received ==-1) {
eth->num_rx_errors++;
if (errno == EAGAIN) {
printf("Lost IF4p5 connection with %s\n", inet_ntoa(eth->dest_addrd.sin_addr));
return -1;
} else if (errno == EWOULDBLOCK) {
block_cnt++;
usleep(10);
if (block_cnt == 1000) {
perror("ETHERNET IF4p5 READ (EWOULDBLOCK): ");
} else {
printf("BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK \n");
goto again;
}
} else {
return(-1);
//perror("ETHERNET IF4p5 READ");
//printf("(%s):\n", strerror(errno));
}
} else {
*timestamp = test_header->sub_type;
eth->rx_actual_nsamps = bytes_received>>1;
eth->rx_count++;
}
}
eth->rx_nsamps = nsamps;
return(bytes_received);
}
int trx_eth_write_udp_IF4p5(openair0_device_t *device, openair0_timestamp_t timestamp, void **buff, int nsamps, int cc, int flags)
{
int nblocks = nsamps;
int bytes_sent = 0;
eth_state_t *eth = (eth_state_t*)device->priv;
ssize_t packet_size;
char str[INET_ADDRSTRLEN];
inet_ntop(AF_INET, &(eth->dest_addrd.sin_addr), str, INET_ADDRSTRLEN);
if (flags == IF4p5_PDLFFT) {
packet_size = UDP_IF4p5_PDLFFT_SIZE_BYTES(nblocks);
} else if (flags == IF4p5_PULFFT) {
packet_size = UDP_IF4p5_PULFFT_SIZE_BYTES(nblocks);
} else if (flags == IF4p5_PULTICK) {
packet_size = UDP_IF4p5_PULTICK_SIZE_BYTES;
} else if ((flags >= IF4p5_PRACH)&&
(flags <= (IF4p5_PRACH+4))) {
packet_size = UDP_HEADER_SIZE_BYTES + IPV4_HEADER_SIZE_BYTES + sizeof_IF4p5_header_t + (nsamps<<1);
} else {
printf("trx_eth_write_udp_IF4p5: unknown flags %d\n",flags);
return(-1);
}
eth->tx_nsamps = nblocks;
bytes_sent = sendto(eth->sockfdd[0/*cc%eth->num_fd*/],
buff[0],
packet_size,
0,
(struct sockaddr*)&eth->dest_addrd,
eth->addr_len);
if (bytes_sent == -1) {
eth->num_tx_errors++;
perror("error writing to remote unit (user) : ");
exit(-1);
} else {
eth->tx_actual_nsamps = bytes_sent>>1;
eth->tx_count++;
}
return (bytes_sent);
}
void *trx_eth_write_udp_cmd(udpTXelem_t *udpTXelem)
{
openair0_device_t *device=udpTXelem->device;
openair0_timestamp_t timestamp = udpTXelem->timestamp;
void **buff = udpTXelem->buff;
int nsamps = udpTXelem->nsamps;
int nant = udpTXelem->nant;
int bytes_sent=0;
eth_state_t *eth = (eth_state_t*)device->priv;
int sendto_flag =0;
fhstate_t *fhstate = &eth->fhstate;
//sendto_flag|=flags;
eth->tx_nsamps=nsamps;
uint64_t last_rxTS = fhstate->TS[0]-fhstate->TS0;
uint64_t TS_advance=0;
if (timestamp > last_rxTS) TS_advance = timestamp - last_rxTS;
else {
LOG_W(PHY,"TS_advance is < 0 TS %llu absslot %llu(%llu) last_rxTS %llu TS_advance %llu samples\n", (unsigned long long)timestamp,(unsigned long long)timestamp/nsamps,((unsigned long long)timestamp/nsamps)%20,(unsigned long long)last_rxTS,(unsigned long long)TS_advance);
free(buff);
return(NULL);
}
if (TS_advance < (nsamps/2)) {
LOG_W(PHY,"Starting TX FH for TS %llu absslot %llu(%llu) last_rxTS %llu TS_advance %llu samples\n",(unsigned long long)timestamp,(unsigned long long)timestamp/nsamps,((unsigned long long)timestamp/nsamps)%20,(unsigned long long)last_rxTS,(unsigned long long)TS_advance);
}
void *buff2;
int nsamps2 = 256>>3;
simde__m256i buff_tx[nsamps2 + 1];
buff2 = (void *)&buff_tx[1] - APP_HEADER_SIZE_BYTES;
/* construct application header */
// ECPRI Protocol revision + reserved bits (1 byte)
*(uint8_t *)buff2 = ECPRIREV;
// ECPRI Message type (1 byte)
*(uint8_t *)(buff2 + 1) = 64;
openair0_timestamp_t TS = timestamp + fhstate->TS0;
TS = (6 * eth->sampling_rate_ratio_d * TS) / eth->sampling_rate_ratio_n;
TS -= eth->txrx_offset;
int TSinc = (6 * 256 * eth->sampling_rate_ratio_d) / eth->sampling_rate_ratio_n;
int len=256;
LOG_D(NR_PHY,
"in eth send: TS %llu (%llu),txrx_offset %d,d %d, n %d, buff[0] %p buff[1] %p\n",
(unsigned long long)TS,
(unsigned long long)timestamp,
eth->txrx_offset,
eth->sampling_rate_ratio_d,
eth->sampling_rate_ratio_n,
buff[0],
buff[1]);
for (int offset=0;offset<nsamps;offset+=256,TS+=TSinc) {
// OAI modified SEQ_ID (4 bytes)
*(uint64_t *)(buff2 + 6) = TS;
if ((offset + 256) <= nsamps) len=1024;
else len = (nsamps-offset)<<2;
// ECPRI Payload Size (2 bytes)
*(uint8_t *)(buff2 + 2) = len>>8;
*(uint8_t *)(buff2 + 3) = len&0xff;
for (int aid = 0; aid<nant; aid++) {
LOG_D(NR_PHY,"TS %llu (TS0 %llu) aa %d : offset %d, len %d\n",(unsigned long long)TS,(unsigned long long)fhstate->TS0,aid,offset,len);
// ECPRI PC_ID (2 bytes)
*(uint16_t *)(buff2 + 4) = aid;
// bring TX data into 12 MSBs
simde__m256i *buff256 = (simde__m256i *)&(((int32_t *)buff[aid])[offset]);
for (int j=0; j<32; j+=8) {
buff_tx[1+j] = simde_mm256_slli_epi16(buff256[j],4);
buff_tx[2+j] = simde_mm256_slli_epi16(buff256[j+1],4);
buff_tx[3+j] = simde_mm256_slli_epi16(buff256[j+2],4);
buff_tx[4+j] = simde_mm256_slli_epi16(buff256[j+3],4);
buff_tx[5+j] = simde_mm256_slli_epi16(buff256[j+4],4);
buff_tx[6+j] = simde_mm256_slli_epi16(buff256[j+5],4);
buff_tx[7+j] = simde_mm256_slli_epi16(buff256[j+6],4);
buff_tx[8+j] = simde_mm256_slli_epi16(buff256[j+7],4);
}
/* Send packet */
bytes_sent = sendto(eth->sockfdd[0],
buff2,
UDP_PACKET_SIZE_BYTES(len>>2),
sendto_flag,
(struct sockaddr*)&eth->dest_addrd,
eth->addr_len);
if ( bytes_sent == -1) {
eth->num_tx_errors++;
perror("ETHERNET WRITE: ");
exit(-1);
} else {
eth->tx_actual_nsamps=bytes_sent>>2;
eth->tx_count++;
}
} // aid
} // offset
free(buff);
LOG_D(NR_PHY,"Returning from eth send\n");
return(NULL);
}
int trx_eth_write_udp(openair0_device_t *device, openair0_timestamp_t timestamp, void **buff, int fd_ind, int nsamps, int flags, int nant)
{
union udpTXReqUnion id = {.s={(uint64_t)timestamp,nsamps,0}};
eth_state_t *eth = (eth_state_t*)device->priv;
notifiedFIFO_elt_t *req=newNotifiedFIFO_elt(sizeof(udpTXelem_t), id.p, eth->utx[fd_ind]->resp,NULL);
udpTXelem_t * udptxelem=(udpTXelem_t *) NotifiedFifoData(req);
udptxelem->device = device;
udptxelem->timestamp = timestamp;
udptxelem->buff = calloc(nant,sizeof(void*));
memcpy(udptxelem->buff,buff,nant*sizeof(void*));
udptxelem->fd_ind = fd_ind;
udptxelem->nsamps = nsamps;
udptxelem->flags = flags;
udptxelem->nant = nant;
pushNotifiedFIFO(eth->utx[fd_ind]->resp, req);
LOG_D(PHY,"Pushed to TX FH FIFO, TS %llu, nsamps %d, nant %d buffs[0] %p buffs[1] %p\n",
(unsigned long long)timestamp,nsamps,nant,udptxelem->buff[0],udptxelem->buff[1]);
return(0);
}
void *udp_write_thread(void *arg) {
udp_ctx_t *utx = (udp_ctx_t *)arg;
utx->resp = malloc(sizeof(*utx->resp));
initNotifiedFIFO(utx->resp);
LOG_D(PHY,"UDP write thread started on core %d\n",sched_getcpu());
while (oai_exit == 0) {
notifiedFIFO_elt_t *res = pullNotifiedFIFO(utx->resp);
udpTXelem_t *udptxelem = (udpTXelem_t *)NotifiedFifoData(res);
LOG_D(PHY,"Pulled from TX FH FIFO, TS %llu, nsamps %d, nant %d\n",(unsigned long long)udptxelem->timestamp,udptxelem->nsamps,udptxelem->nant);
trx_eth_write_udp_cmd(udptxelem);
// send data to RU
delNotifiedFIFO_elt(res);
}
free(utx->resp);
return(NULL);
}
void *udp_read_thread(void *arg)
{
openair0_timestamp_t TS;
int aid;
udp_ctx_t *u = (udp_ctx_t *)arg;
openair0_device_t *device=u->device;
eth_state_t *eth = device->priv;
fhstate_t *fhstate = &eth->fhstate;
char buffer[UDP_PACKET_SIZE_BYTES(256)];
int first_read=0;
while (oai_exit == 0) {
LOG_I(PHY,
"UDP read thread %d on core %d, waiting for start sampling_rate_d %d, sampling_rate_n %d\n",
u->thread_id,
sched_getcpu(),
eth->sampling_rate_ratio_n,
eth->sampling_rate_ratio_d);
while (fhstate->active > 0) {
ssize_t count = recvfrom(((eth_state_t*)device->priv)->sockfdd[0],
buffer,sizeof(buffer),0,
(struct sockaddr *)&((eth_state_t*)device->priv)->dest_addrd,
(socklen_t *)&((eth_state_t*)device->priv)->addr_len);
/* log and skip processing in case of error from recvfrom */
/* (to be refined if needed) */
if (count == 0) {
LOG_E(PHY, "recvfrom returned 0\n");
continue;
}
if (count < 0) {
LOG_E(PHY, "recvfrom failed (%s)\n", strerror(errno));
continue;
}
/* if oai_exit is 1 here, don't access the array rxbase,
* it may have been freed(), so let's break at this point
*/
if (oai_exit)
break;
aid = *(uint16_t*)(&buffer[ECPRICOMMON_BYTES]);
TS = *(openair0_timestamp_t *)(&buffer[ECPRICOMMON_BYTES+ECPRIPCID_BYTES]);
// convert TS to samples, /6 for AW2S @ 30.72 Ms/s, this is converted for other sample rates in OAI application
TS = (eth->sampling_rate_ratio_n * TS) / (eth->sampling_rate_ratio_d * 6);
AssertFatal(aid < 8,"Cannot handle more than 8 antennas, got aid %d\n",aid);
fhstate->r[aid]=1;
if (aid==0 && first_read == 0) fhstate->TS0 = TS;
first_read = 1;
/* store the timestamp value from packet's header */
fhstate->TS[aid] = TS;
int64_t offset = TS - fhstate->TS0;
if (offset > 0) offset = offset % device->openair0_cfg->rxsize;
else offset = TS % device->openair0_cfg->rxsize + ((((uint64_t)1)<<63)-(fhstate->TS0-1)) % device->openair0_cfg->rxsize;
// need to do memcpy since there is no guarantee that aid is the same each time, otherwise we could have used
// zero-copy and corrected the header component.
memcpy((void*)(device->openair0_cfg->rxbase[aid]+offset),
(void*)&buffer[APP_HEADER_SIZE_BYTES],
count-APP_HEADER_SIZE_BYTES);
LOG_D(PHY,"UDP read thread_id %d (%d), aid %d, TS %llu, TS0 %llu, offset %ld\n",(int)u->thread_id,(int)sched_getcpu(),aid,(unsigned long long)TS,(unsigned long long)fhstate->TS0,offset);
}
sleep(1);
}
/* let's unblock reader (maybe not the best way to do it) */
fhstate->first_read = 0;
fhstate->r[0] = 1;
return(0);
}
int trx_eth_read_udp(openair0_device_t *device, openair0_timestamp_t *timestamp, uint32_t **buff, int nsamps)
{
eth_state_t *eth = device->priv;
fhstate_t *fhstate = &eth->fhstate;
openair0_timestamp_t prev_read_TS= fhstate->TS_read;
volatile openair0_timestamp_t min_TS;
// block until FH is ready
while (fhstate->r[0] == 0 || fhstate->r[1] == 0 || fhstate->r[2] == 0 || fhstate->r[3] == 0 ||
fhstate->r[4] == 0 || fhstate->r[5] == 0 || fhstate->r[6] == 0 || fhstate->r[7] == 0) usleep(100);
// get minimum TS over all antennas
min_TS = (volatile openair0_timestamp_t)fhstate->TS[0];
for (int i=1;i<device->openair0_cfg->rx_num_channels;i++) min_TS = min(min_TS,fhstate->TS[i]);
// poll/sleep until we accumulated enough samples on each antenna port
int count=0;
while (fhstate->first_read == 1 && min_TS < (fhstate->TS0+prev_read_TS + nsamps)) {
usleep(10);
min_TS = (volatile openair0_timestamp_t)fhstate->TS[0];
for (int i=1;i<device->openair0_cfg->rx_num_channels;i++) min_TS = min(min_TS,(volatile openair0_timestamp_t)fhstate->TS[i]);
count++;
}
if (fhstate->first_read == 0) {
*timestamp = 0;
fhstate->TS_read = *timestamp+nsamps;
LOG_D(PHY,"first read : TS_read %llu, TS %llu state (%d,%d,%d,%d,%d,%d,%d,%d)\n",(unsigned long long)fhstate->TS_read,(unsigned long long)*timestamp,
fhstate->r[0],fhstate->r[1],fhstate->r[2],fhstate->r[3],fhstate->r[4],fhstate->r[5],fhstate->r[6],fhstate->r[7]);
}
else {
*timestamp = fhstate->TS_read;
fhstate->TS_read = prev_read_TS + nsamps;
LOG_D(PHY,"TS_read %llu (%llu, %llu), min_TS %llu, prev_read_TS %llu, nsamps %d, fhstate->TS0+prev_TS+nsamps %llu, wait count %d x 100us\n",(unsigned long long)fhstate->TS_read,(unsigned long long)*timestamp/nsamps,((unsigned long long)*timestamp/nsamps)%20,(unsigned long long)min_TS,(unsigned long long)prev_read_TS,nsamps,(unsigned long long)(fhstate->TS0+prev_read_TS+nsamps),count);
}
fhstate->first_read = 1;
return (nsamps);
}
int trx_eth_ctlsend_udp(openair0_device_t *device, void *msg, ssize_t msg_len)
{
return(sendto(((eth_state_t*)device->priv)->sockfdc,
msg,
msg_len,
0,
(struct sockaddr *)&((eth_state_t*)device->priv)->dest_addrc,
((eth_state_t*)device->priv)->addr_len));
}
int trx_eth_ctlrecv_udp(openair0_device_t *device, void *msg, ssize_t msg_len)
{
return (recvfrom(((eth_state_t*)device->priv)->sockfdc,
msg,
msg_len,
0,
(struct sockaddr *)&((eth_state_t*)device->priv)->dest_addrc,
(socklen_t *)&((eth_state_t*)device->priv)->addr_len));
}
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