/**
* Unlink the memory descriptor from any ME it may be linked to and release
* the internal resources associated with it. As a result, active messages
* associated with the MD may get aborted.
*
* This function does not free the memory region associated with the MD;
* i.e., the memory the user allocated for this MD. If the ME associated with
* this MD is not NULL and was created with auto unlink enabled, the ME is
* unlinked as well (see LNetMEAttach()).
*
* Explicitly unlinking a MD via this function call has the same behavior as
* a MD that has been automatically unlinked, except that no LNET_EVENT_UNLINK
* is generated in the latter case.
*
* An unlinked event can be reported in two ways:
* - If there's no pending operations on the MD, it's unlinked immediately
* and an LNET_EVENT_UNLINK event is logged before this function returns.
* - Otherwise, the MD is only marked for deletion when this function
* returns, and the unlinked event will be piggybacked on the event of
* the completion of the last operation by setting the unlinked field of
* the event. No dedicated LNET_EVENT_UNLINK event is generated.
*
* Note that in both cases the unlinked field of the event is always set; no
* more event will happen on the MD after such an event is logged.
*
* \param mdh A handle for the MD to be unlinked.
*
* \retval 0 On success.
* \retval -ENOENT If \a mdh does not point to a valid MD object.
*/
int
LNetMDUnlink (lnet_handle_md_t mdh)
{
lnet_event_t ev;
lnet_libmd_t *md;
int cpt;
LASSERT(the_lnet.ln_init);
LASSERT(the_lnet.ln_refcount > 0);
cpt = lnet_cpt_of_cookie(mdh.cookie);
lnet_res_lock(cpt);
md = lnet_handle2md(&mdh);
if (md == NULL) {
lnet_res_unlock(cpt);
return -ENOENT;
}
md->md_flags |= LNET_MD_FLAG_ABORTED;
/* If the MD is busy, lnet_md_unlink just marks it for deletion, and
* when the LND is done, the completion event flags that the MD was
* unlinked. Otherwise, we enqueue an event now... */
if (md->md_eq != NULL && md->md_refcount == 0) {
lnet_build_unlink_event(md, &ev);
lnet_eq_enqueue_event(md->md_eq, &ev);
}
lnet_md_unlink(md);
lnet_res_unlock(cpt);
return 0;
}
void
lnet_finalize (__unusedx lnet_ni_t *ni, lnet_msg_t *msg, int status)
{
#ifdef __KERNEL__
int i;
int my_slot;
#endif
lnet_libmd_t *md;
LASSERT (!in_interrupt ());
if (msg == NULL)
return;
#if 0
CDEBUG(D_WARNING, "%s msg->%s Flags:%s%s%s%s%s%s%s%s%s%s%s txp %s rxp %s\n",
lnet_msgtyp2str(msg->msg_type), libcfs_id2str(msg->msg_target),
msg->msg_target_is_router ? "t" : "",
msg->msg_routing ? "X" : "",
msg->msg_ack ? "A" : "",
msg->msg_sending ? "S" : "",
msg->msg_receiving ? "R" : "",
msg->msg_delayed ? "d" : "",
msg->msg_txcredit ? "C" : "",
msg->msg_peertxcredit ? "c" : "",
msg->msg_rtrcredit ? "F" : "",
msg->msg_peerrtrcredit ? "f" : "",
msg->msg_onactivelist ? "!" : "",
msg->msg_txpeer == NULL ? "<none>" : libcfs_nid2str(msg->msg_txpeer->lp_nid),
msg->msg_rxpeer == NULL ? "<none>" : libcfs_nid2str(msg->msg_rxpeer->lp_nid));
#endif
LNET_LOCK();
LASSERT (msg->msg_onactivelist);
msg->msg_ev.status = status;
md = msg->msg_md;
if (md != NULL) {
int unlink;
/* Now it's safe to drop my caller's ref */
md->md_refcount--;
LASSERT (md->md_refcount >= 0);
unlink = lnet_md_unlinkable(md);
msg->msg_ev.unlinked = unlink;
if (md->md_eq != NULL)
lnet_enq_event_locked(md->md_eq, &msg->msg_ev);
if (unlink)
lnet_md_unlink(md);
msg->msg_md = NULL;
}
list_add_tail (&msg->msg_list, &the_lnet.ln_finalizeq);
/* Recursion breaker. Don't complete the message here if I am (or
* enough other threads are) already completing messages */
#ifdef __KERNEL__
my_slot = -1;
for (i = 0; i < the_lnet.ln_nfinalizers; i++) {
if (the_lnet.ln_finalizers[i] == cfs_current())
goto out;
if (my_slot < 0 && the_lnet.ln_finalizers[i] == NULL)
my_slot = i;
}
if (my_slot < 0)
goto out;
the_lnet.ln_finalizers[my_slot] = cfs_current();
#else
if (the_lnet.ln_finalizing)
goto out;
the_lnet.ln_finalizing = 1;
#endif
while (!list_empty(&the_lnet.ln_finalizeq)) {
msg = list_entry(the_lnet.ln_finalizeq.next,
lnet_msg_t, msg_list);
list_del(&msg->msg_list);
/* NB drops and regains the lnet lock if it actually does
* anything, so my finalizing friends can chomp along too */
lnet_complete_msg_locked(msg);
}
#ifdef __KERNEL__
the_lnet.ln_finalizers[my_slot] = NULL;
#else
the_lnet.ln_finalizing = 0;
#endif
out:
LNET_UNLOCK();
}
