void
lwt_fini ()
{
int i;
lwt_control(0, 0);
for (i = 0; i < cfs_num_online_cpus(); i++)
while (lwt_cpus[i].lwtc_current_page != NULL) {
lwt_page_t *lwtp = lwt_cpus[i].lwtc_current_page;
if (cfs_list_empty (&lwtp->lwtp_list)) {
lwt_cpus[i].lwtc_current_page = NULL;
} else {
lwt_cpus[i].lwtc_current_page =
cfs_list_entry (lwtp->lwtp_list.next,
lwt_page_t, lwtp_list);
cfs_list_del (&lwtp->lwtp_list);
}
__free_page (lwtp->lwtp_page);
LIBCFS_FREE (lwtp, sizeof (*lwtp));
}
}
int
cfs_wi_check_events (void)
{
int n = 0;
cfs_workitem_t *wi;
cfs_list_t *q;
cfs_spin_lock(&cfs_wi_data.wi_glock);
for (;;) {
/** rerunq is always empty for userspace */
if (!cfs_list_empty(&cfs_wi_data.wi_scheds[1].ws_runq))
q = &cfs_wi_data.wi_scheds[1].ws_runq;
else if (!cfs_list_empty(&cfs_wi_data.wi_scheds[0].ws_runq))
q = &cfs_wi_data.wi_scheds[0].ws_runq;
else
break;
wi = cfs_list_entry(q->next, cfs_workitem_t, wi_list);
cfs_list_del_init(&wi->wi_list);
LASSERT (wi->wi_scheduled);
wi->wi_scheduled = 0;
cfs_spin_unlock(&cfs_wi_data.wi_glock);
n++;
(*wi->wi_action) (wi);
cfs_spin_lock(&cfs_wi_data.wi_glock);
}
cfs_spin_unlock(&cfs_wi_data.wi_glock);
return n;
}
/* Return the first tx from tx_list with piggybacked zc_ack
* from zcack_list when possible. If tx_list is empty, return
* brand new noop tx for zc_ack from zcack_list. Return NULL
* if an error happened */
usock_tx_t *
usocklnd_try_piggyback(cfs_list_t *tx_list_p,
cfs_list_t *zcack_list_p)
{
usock_tx_t *tx;
usock_zc_ack_t *zc_ack;
/* assign tx and zc_ack */
if (cfs_list_empty(tx_list_p))
tx = NULL;
else {
tx = cfs_list_entry(tx_list_p->next, usock_tx_t, tx_list);
cfs_list_del(&tx->tx_list);
/* already piggybacked or partially send */
if (tx->tx_msg.ksm_zc_cookies[1] != 0 ||
tx->tx_resid != tx->tx_nob)
return tx;
}
if (cfs_list_empty(zcack_list_p)) {
/* nothing to piggyback */
return tx;
} else {
zc_ack = cfs_list_entry(zcack_list_p->next,
usock_zc_ack_t, zc_list);
cfs_list_del(&zc_ack->zc_list);
}
if (tx != NULL)
/* piggyback the zc-ack cookie */
tx->tx_msg.ksm_zc_cookies[1] = zc_ack->zc_cookie;
else
/* cannot piggyback, need noop */
tx = usocklnd_create_noop_tx(zc_ack->zc_cookie);
LIBCFS_FREE (zc_ack, sizeof(*zc_ack));
return tx;
}
int
lwt_control (int enable, int clear)
{
lwt_page_t *p;
int i;
int j;
if (!cfs_capable(CFS_CAP_SYS_ADMIN))
return (-EPERM);
if (!enable) {
LWT_EVENT(0,0,0,0);
lwt_enabled = 0;
cfs_mb();
/* give people some time to stop adding traces */
cfs_schedule_timeout(10);
}
for (i = 0; i < cfs_num_online_cpus(); i++) {
p = lwt_cpus[i].lwtc_current_page;
if (p == NULL)
return (-ENODATA);
if (!clear)
continue;
for (j = 0; j < lwt_pages_per_cpu; j++) {
memset(p->lwtp_events, 0, PAGE_CACHE_SIZE);
p = cfs_list_entry (p->lwtp_list.next,
lwt_page_t, lwtp_list);
}
}
if (enable) {
lwt_enabled = 1;
cfs_mb();
LWT_EVENT(0,0,0,0);
}
return (0);
}
int
lwt_snapshot(cfs_cycles_t *now, int *ncpu, int *total_size,
void *user_ptr, int user_size)
{
const int events_per_page = PAGE_CACHE_SIZE / sizeof(lwt_event_t);
const int bytes_per_page = events_per_page * sizeof(lwt_event_t);
lwt_page_t *p;
int i;
int j;
if (!cfs_capable(CFS_CAP_SYS_ADMIN))
return (-EPERM);
*ncpu = cfs_num_online_cpus();
*total_size = cfs_num_online_cpus() * lwt_pages_per_cpu *
bytes_per_page;
*now = get_cycles();
if (user_ptr == NULL)
return (0);
for (i = 0; i < cfs_num_online_cpus(); i++) {
p = lwt_cpus[i].lwtc_current_page;
if (p == NULL)
return -ENODATA;
for (j = 0; j < lwt_pages_per_cpu; j++) {
if (copy_to_user(user_ptr, p->lwtp_events,
bytes_per_page))
return -EFAULT;
user_ptr = ((char *)user_ptr) + bytes_per_page;
p = cfs_list_entry(p->lwtp_list.next,
lwt_page_t, lwtp_list);
}
}
return (0);
}
static int
cfs_wi_scheduler (void *arg)
{
int id = (int)(long_ptr_t) arg;
int serial = (id == -1);
char name[24];
cfs_wi_sched_t *sched;
if (serial) {
sched = &cfs_wi_data.wi_scheds[cfs_wi_data.wi_nsched - 1];
cfs_daemonize("wi_serial_sd");
} else {
/* will be sched = &cfs_wi_data.wi_scheds[id] in the future */
sched = &cfs_wi_data.wi_scheds[0];
snprintf(name, sizeof(name), "cfs_wi_sd%03d", id);
cfs_daemonize(name);
}
cfs_block_allsigs();
cfs_wi_sched_lock(sched);
while (!sched->ws_shuttingdown) {
int nloops = 0;
int rc;
cfs_workitem_t *wi;
while (!cfs_list_empty(&sched->ws_runq) &&
nloops < CFS_WI_RESCHED) {
wi = cfs_list_entry(sched->ws_runq.next,
cfs_workitem_t, wi_list);
LASSERT (wi->wi_scheduled && !wi->wi_running);
cfs_list_del_init(&wi->wi_list);
wi->wi_running = 1;
wi->wi_scheduled = 0;
cfs_wi_sched_unlock(sched);
nloops++;
rc = (*wi->wi_action) (wi);
cfs_wi_sched_lock(sched);
if (rc != 0) /* WI should be dead, even be freed! */
continue;
wi->wi_running = 0;
if (cfs_list_empty(&wi->wi_list))
continue;
LASSERT (wi->wi_scheduled);
/* wi is rescheduled, should be on rerunq now, we
* move it to runq so it can run action now */
cfs_list_move_tail(&wi->wi_list, &sched->ws_runq);
}
if (!cfs_list_empty(&sched->ws_runq)) {
cfs_wi_sched_unlock(sched);
/* don't sleep because some workitems still
* expect me to come back soon */
cfs_cond_resched();
cfs_wi_sched_lock(sched);
continue;
}
cfs_wi_sched_unlock(sched);
cfs_wait_event_interruptible_exclusive(sched->ws_waitq,
!cfs_wi_sched_cansleep(sched), rc);
cfs_wi_sched_lock(sched);
}
cfs_wi_sched_unlock(sched);
cfs_spin_lock(&cfs_wi_data.wi_glock);
cfs_wi_data.wi_nthreads--;
cfs_spin_unlock(&cfs_wi_data.wi_glock);
return 0;
}
