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bouwhuim.nikhef.nl dee2668a61 newest version WRPC
2013-09-10 08:08:59 +00:00

127 lines
2.8 KiB
C

/*
* Alessandro Rubini for CERN, 2011 -- public domain
*/
/*
* This is the main loop for posix stuff.
*/
#include <stdlib.h>
#include <errno.h>
#include <sys/select.h>
#include <linux/if_ether.h>
#include <ppsi/ppsi.h>
#include "posix.h"
/* Call pp_state_machine for each instance. To be called periodically,
* when no packets are incoming */
static int run_all_state_machines(struct pp_globals *ppg)
{
int j;
int delay_ms = 0, delay_ms_j;
for (j = 0; j < ppg->nlinks; j++) {
struct pp_instance *ppi = &ppg->pp_instances[j];
delay_ms_j = pp_state_machine(ppi, NULL, 0);
/* delay_ms is the least delay_ms among all instances */
if (delay_ms == 0)
delay_ms = delay_ms_j;
else
delay_ms = delay_ms_j < delay_ms ? delay_ms_j : delay_ms;
}
return delay_ms;
}
void posix_main_loop(struct pp_globals *ppg)
{
struct pp_instance *ppi;
int delay_ms;
int j;
/* Initialize each link's state machine */
for (j = 0; j < ppg->nlinks; j++) {
ppi = &ppg->pp_instances[j];
/*
* If we are sending or receiving raw ethernet frames,
* the ptp payload is one-eth-header bytes into the frame
*/
if (ppi->ethernet_mode)
NP(ppi)->ptp_offset = ETH_HLEN;
/*
* The main loop here is based on select. While we are not
* doing anything else but the protocol, this allows extra stuff
* to fit.
*/
ppi->is_new_state = 1;
}
delay_ms = run_all_state_machines(ppg);
while (1) {
int i;
if (ppg->ebest_updated) {
/* If Ebest was changed in previous loop, run best master
* clock before checking for new packets, which would affect
* port state again */
for (j = 0; j < ppg->nlinks; j++) {
int new_state;
struct pp_instance *ppi = &ppg->pp_instances[j];
new_state = bmc(ppi);
if (new_state != ppi->state) {
ppi->state = new_state;
ppi->is_new_state = 1;
}
}
ppg->ebest_updated = 0;
}
i = posix_net_check_pkt(ppg, delay_ms);
if (i < 0)
continue;
if (i == 0) {
delay_ms = run_all_state_machines(ppg);
continue;
}
/* If delay_ms is -1, the above posix_net_check_pkt will continue
* consuming the previous timeout (see its implementation).
* This ensures that every state machine is called at least once
* every delay_ms */
delay_ms = -1;
for (j = 0; j < ppg->nlinks; j++) {
ppi = &ppg->pp_instances[j];
if ((NP(ppi)->ch[PP_NP_GEN].pkt_present) ||
(NP(ppi)->ch[PP_NP_EVT].pkt_present)) {
/* We got some packets. If not ours, go on to the next ppi */
i = ppi->n_ops->recv(ppi, ppi->rx_frame,
PP_MAX_FRAME_LENGTH - 4,
&ppi->last_rcv_time);
ppi->last_rcv_time.seconds += DSPRO(ppi)->currentUtcOffset;
if (i < PP_MINIMUM_LENGTH) {
pp_diag(ppi, frames, 1, "Error or short packet: %d < %d\n", i,
PP_MINIMUM_LENGTH
);
continue;
}
pp_state_machine(ppi, ppi->rx_ptp,
i - NP(ppi)->ptp_offset);
}
}
}
}