/* Process a mq_status. return 1, if a read made progress. 0 else */
static
int pscom_psm_process(psm_mq_status_t *status)
{
uintptr_t c = (uintptr_t)status->context & 7;
pspsm_con_info_t *ci = (pspsm_con_info_t *)((uintptr_t)status->context & ~(uintptr_t)7);
pscom_con_t *con = ci->con;
assert(ci->magic == UINTMAX_C(0xdeadbeefcafebabe));
switch (c) {
case 0:
/* first send request */
assert(ci->sreqs[0] != PSM_MQ_REQINVALID);
poll_user_dec();
ci->sreqs[0] = PSM_MQ_REQINVALID;
/* pspsm_dprint(0, "Send0 done %p len %d con %s\n", ci->iov[0].iov_base,
(int)ci->iov[0].iov_len, ci->con->pub.remote_con_info.name); */
if (ci->sreqs[1] == PSM_MQ_REQINVALID){
pscom_write_done(con, ci->req, ci->iov[0].iov_len + ci->iov[1].iov_len);
ci->req = NULL;
}
break;
case 1:
/* second send request */
assert(ci->sreqs[1] != PSM_MQ_REQINVALID);
poll_user_dec();
ci->sreqs[1] = PSM_MQ_REQINVALID;
/* pspsm_dprint(0, "Send1 done %p len %d con %s\n", ci->iov[1].iov_base,
(int)ci->iov[1].iov_len, ci->con->pub.remote_con_info.name); */
if (ci->sreqs[0] == PSM_MQ_REQINVALID){
pscom_write_done(con, ci->req, ci->iov[0].iov_len + ci->iov[1].iov_len);
ci->req = NULL;
}
break;
case 2:
/* receive request */
assert(ci->rbuf);
assert(status->msg_length == status->nbytes);
ci->rreq = PSM_MQ_REQINVALID;
/* pspsm_dprint(0, "read done %p len %d con %s\n", ci->rbuf,
(int)status->msg_length, ci->con->pub.remote_con_info.name); */
pscom_read_done_unlock(con, ci->rbuf, status->msg_length);
ci->rbuf = NULL;
if (con->arch.psm.reading) {
/* There is more to read. Post the next receive request */
pscom_psm_do_read(con);
}
return 1;
break;
default:
/* this shouldn't happen */
assert(0);
}
return 0;
}
static
void pscom_psm_read_stop(pscom_con_t *con)
{
if (con->arch.psm.reading) {
con->arch.psm.reading = 0;
poll_user_dec();
}
}
static
void pscom_mxm_do_write(pscom_con_t *con)
{
struct iovec iov[2];
psmxm_con_info_t *ci = con->arch.mxm.ci;
pscom_req_t *req = con->arch.mxm.sreq;
int polling = 0;
if (req) {
// proceed with the send from the last iteration.
polling = 1;
unsigned sent = psmxm_send_progress(ci);
if (sent) {
pscom_write_done(con, req, sent);
} else {
/* FIXME: we might want to send more than one message at a
time. */
/* send in progress. wait for completion before
transmitting the next message. */
return;
}
}
/* get and post a new write request */
req = pscom_write_get_iov(con, iov);
if (req) {
int ret = psmxm_sendv(ci, iov, iov[0].iov_len + iov[1].iov_len);
if (ret > 0){
/* sending ret bytes. Complete this request in the next iteration. */
if (!polling) poll_user_inc();
} else if (ret == -EAGAIN){
/* Try again later. */
req = NULL;
} else {
assert(ret == -EPIPE);
errno = -ret;
pscom_con_error(con, PSCOM_OP_WRITE, PSCOM_ERR_STDERROR);
req = NULL;
}
}
if (!req && polling) poll_user_dec();
// Remember the current request or NULL in the case of EAGAIN.
con->arch.mxm.sreq = req;
}
