Commit
8f3d65c16679 ("net/smc: fix wait on already cleared link")
introduced link refcounting to avoid waits on already cleared links.
This patch extents and improves the refcounting to cover all
remaining possible cases for this kind of error situation.
Fixes:
15e1b99aadfb ("net/smc: no WR buffer wait for terminating link group")
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
+ if (!smc_wr_tx_link_hold(link))
+ return -ENOLINK;
rc = smc_cdc_get_free_slot(conn, link, &wr_buf, NULL, &pend);
if (rc)
rc = smc_cdc_get_free_slot(conn, link, &wr_buf, NULL, &pend);
if (rc)
spin_lock_bh(&conn->send_lock);
if (link != conn->lnk) {
spin_lock_bh(&conn->send_lock);
if (link != conn->lnk) {
spin_unlock_bh(&conn->send_lock);
smc_wr_tx_put_slot(link,
(struct smc_wr_tx_pend_priv *)pend);
spin_unlock_bh(&conn->send_lock);
smc_wr_tx_put_slot(link,
(struct smc_wr_tx_pend_priv *)pend);
+ smc_wr_tx_link_put(link);
if (again)
return -ENOLINK;
again = true;
if (again)
return -ENOLINK;
again = true;
}
rc = smc_cdc_msg_send(conn, wr_buf, pend);
spin_unlock_bh(&conn->send_lock);
}
rc = smc_cdc_msg_send(conn, wr_buf, pend);
spin_unlock_bh(&conn->send_lock);
+put_out:
+ smc_wr_tx_link_put(link);
to_lnk = &lgr->lnk[i];
break;
}
to_lnk = &lgr->lnk[i];
break;
}
+ if (!to_lnk || !smc_wr_tx_link_hold(to_lnk)) {
smc_lgr_terminate_sched(lgr);
return NULL;
}
smc_lgr_terminate_sched(lgr);
return NULL;
}
read_unlock_bh(&lgr->conns_lock);
/* pre-fetch buffer outside of send_lock, might sleep */
rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
read_unlock_bh(&lgr->conns_lock);
/* pre-fetch buffer outside of send_lock, might sleep */
rc = smc_cdc_get_free_slot(conn, to_lnk, &wr_buf, NULL, &pend);
- if (rc) {
- smcr_link_down_cond_sched(to_lnk);
- return NULL;
- }
+ if (rc)
+ goto err_out;
/* avoid race with smcr_tx_sndbuf_nonempty() */
spin_lock_bh(&conn->send_lock);
smc_switch_link_and_count(conn, to_lnk);
rc = smc_switch_cursor(smc, pend, wr_buf);
spin_unlock_bh(&conn->send_lock);
sock_put(&smc->sk);
/* avoid race with smcr_tx_sndbuf_nonempty() */
spin_lock_bh(&conn->send_lock);
smc_switch_link_and_count(conn, to_lnk);
rc = smc_switch_cursor(smc, pend, wr_buf);
spin_unlock_bh(&conn->send_lock);
sock_put(&smc->sk);
- if (rc) {
- smcr_link_down_cond_sched(to_lnk);
- return NULL;
- }
+ if (rc)
+ goto err_out;
goto again;
}
read_unlock_bh(&lgr->conns_lock);
goto again;
}
read_unlock_bh(&lgr->conns_lock);
+ smc_wr_tx_link_put(to_lnk);
+
+err_out:
+ smcr_link_down_cond_sched(to_lnk);
+ smc_wr_tx_link_put(to_lnk);
+ return NULL;
}
static void smcr_buf_unuse(struct smc_buf_desc *rmb_desc,
}
static void smcr_buf_unuse(struct smc_buf_desc *rmb_desc,
struct smc_wr_buf *wr_buf;
int rc;
struct smc_wr_buf *wr_buf;
int rc;
+ if (!smc_wr_tx_link_hold(link))
+ return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
confllc = (struct smc_llc_msg_confirm_link *)wr_buf;
memset(confllc, 0, sizeof(*confllc));
confllc->hd.common.type = SMC_LLC_CONFIRM_LINK;
confllc = (struct smc_llc_msg_confirm_link *)wr_buf;
memset(confllc, 0, sizeof(*confllc));
confllc->hd.common.type = SMC_LLC_CONFIRM_LINK;
confllc->max_links = SMC_LLC_ADD_LNK_MAX_LINKS;
/* send llc message */
rc = smc_wr_tx_send(link, pend);
confllc->max_links = SMC_LLC_ADD_LNK_MAX_LINKS;
/* send llc message */
rc = smc_wr_tx_send(link, pend);
+put_out:
+ smc_wr_tx_link_put(link);
struct smc_link *link;
int i, rc, rtok_ix;
struct smc_link *link;
int i, rc, rtok_ix;
+ if (!smc_wr_tx_link_hold(send_link))
+ return -ENOLINK;
rc = smc_llc_add_pending_send(send_link, &wr_buf, &pend);
if (rc)
rc = smc_llc_add_pending_send(send_link, &wr_buf, &pend);
if (rc)
rkeyllc = (struct smc_llc_msg_confirm_rkey *)wr_buf;
memset(rkeyllc, 0, sizeof(*rkeyllc));
rkeyllc->hd.common.type = SMC_LLC_CONFIRM_RKEY;
rkeyllc = (struct smc_llc_msg_confirm_rkey *)wr_buf;
memset(rkeyllc, 0, sizeof(*rkeyllc));
rkeyllc->hd.common.type = SMC_LLC_CONFIRM_RKEY;
(u64)sg_dma_address(rmb_desc->sgt[send_link->link_idx].sgl));
/* send llc message */
rc = smc_wr_tx_send(send_link, pend);
(u64)sg_dma_address(rmb_desc->sgt[send_link->link_idx].sgl));
/* send llc message */
rc = smc_wr_tx_send(send_link, pend);
+put_out:
+ smc_wr_tx_link_put(send_link);
struct smc_wr_buf *wr_buf;
int rc;
struct smc_wr_buf *wr_buf;
int rc;
+ if (!smc_wr_tx_link_hold(link))
+ return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
rkeyllc = (struct smc_llc_msg_delete_rkey *)wr_buf;
memset(rkeyllc, 0, sizeof(*rkeyllc));
rkeyllc->hd.common.type = SMC_LLC_DELETE_RKEY;
rkeyllc = (struct smc_llc_msg_delete_rkey *)wr_buf;
memset(rkeyllc, 0, sizeof(*rkeyllc));
rkeyllc->hd.common.type = SMC_LLC_DELETE_RKEY;
rkeyllc->rkey[0] = htonl(rmb_desc->mr_rx[link->link_idx]->rkey);
/* send llc message */
rc = smc_wr_tx_send(link, pend);
rkeyllc->rkey[0] = htonl(rmb_desc->mr_rx[link->link_idx]->rkey);
/* send llc message */
rc = smc_wr_tx_send(link, pend);
+put_out:
+ smc_wr_tx_link_put(link);
struct smc_wr_buf *wr_buf;
int rc;
struct smc_wr_buf *wr_buf;
int rc;
+ if (!smc_wr_tx_link_hold(link))
+ return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
addllc = (struct smc_llc_msg_add_link *)wr_buf;
memset(addllc, 0, sizeof(*addllc));
addllc = (struct smc_llc_msg_add_link *)wr_buf;
memset(addllc, 0, sizeof(*addllc));
}
/* send llc message */
rc = smc_wr_tx_send(link, pend);
}
/* send llc message */
rc = smc_wr_tx_send(link, pend);
+put_out:
+ smc_wr_tx_link_put(link);
struct smc_wr_buf *wr_buf;
int rc;
struct smc_wr_buf *wr_buf;
int rc;
+ if (!smc_wr_tx_link_hold(link))
+ return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
delllc = (struct smc_llc_msg_del_link *)wr_buf;
memset(delllc, 0, sizeof(*delllc));
delllc = (struct smc_llc_msg_del_link *)wr_buf;
memset(delllc, 0, sizeof(*delllc));
delllc->reason = htonl(reason);
/* send llc message */
rc = smc_wr_tx_send(link, pend);
delllc->reason = htonl(reason);
/* send llc message */
rc = smc_wr_tx_send(link, pend);
+put_out:
+ smc_wr_tx_link_put(link);
struct smc_wr_buf *wr_buf;
int rc;
struct smc_wr_buf *wr_buf;
int rc;
+ if (!smc_wr_tx_link_hold(link))
+ return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
testllc = (struct smc_llc_msg_test_link *)wr_buf;
memset(testllc, 0, sizeof(*testllc));
testllc->hd.common.type = SMC_LLC_TEST_LINK;
testllc = (struct smc_llc_msg_test_link *)wr_buf;
memset(testllc, 0, sizeof(*testllc));
testllc->hd.common.type = SMC_LLC_TEST_LINK;
memcpy(testllc->user_data, user_data, sizeof(testllc->user_data));
/* send llc message */
rc = smc_wr_tx_send(link, pend);
memcpy(testllc->user_data, user_data, sizeof(testllc->user_data));
/* send llc message */
rc = smc_wr_tx_send(link, pend);
+put_out:
+ smc_wr_tx_link_put(link);
struct smc_wr_buf *wr_buf;
int rc;
struct smc_wr_buf *wr_buf;
int rc;
- if (!smc_link_usable(link))
+ if (!smc_wr_tx_link_hold(link))
return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
memcpy(wr_buf, llcbuf, sizeof(union smc_llc_msg));
memcpy(wr_buf, llcbuf, sizeof(union smc_llc_msg));
- return smc_wr_tx_send(link, pend);
+ rc = smc_wr_tx_send(link, pend);
+put_out:
+ smc_wr_tx_link_put(link);
+ return rc;
}
/* schedule an llc send on link, may wait for buffers,
}
/* schedule an llc send on link, may wait for buffers,
struct smc_wr_buf *wr_buf;
int rc;
struct smc_wr_buf *wr_buf;
int rc;
- if (!smc_link_usable(link))
+ if (!smc_wr_tx_link_hold(link))
return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
memcpy(wr_buf, llcbuf, sizeof(union smc_llc_msg));
memcpy(wr_buf, llcbuf, sizeof(union smc_llc_msg));
- return smc_wr_tx_send_wait(link, pend, SMC_LLC_WAIT_TIME);
+ rc = smc_wr_tx_send_wait(link, pend, SMC_LLC_WAIT_TIME);
+put_out:
+ smc_wr_tx_link_put(link);
+ return rc;
}
/********************************* receive ***********************************/
}
/********************************* receive ***********************************/
struct smc_buf_desc *rmb;
u8 n;
struct smc_buf_desc *rmb;
u8 n;
+ if (!smc_wr_tx_link_hold(link))
+ return -ENOLINK;
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
rc = smc_llc_add_pending_send(link, &wr_buf, &pend);
if (rc)
addc_llc = (struct smc_llc_msg_add_link_cont *)wr_buf;
memset(addc_llc, 0, sizeof(*addc_llc));
addc_llc = (struct smc_llc_msg_add_link_cont *)wr_buf;
memset(addc_llc, 0, sizeof(*addc_llc));
addc_llc->hd.length = sizeof(struct smc_llc_msg_add_link_cont);
if (lgr->role == SMC_CLNT)
addc_llc->hd.flags |= SMC_LLC_FLAG_RESP;
addc_llc->hd.length = sizeof(struct smc_llc_msg_add_link_cont);
if (lgr->role == SMC_CLNT)
addc_llc->hd.flags |= SMC_LLC_FLAG_RESP;
- return smc_wr_tx_send(link, pend);
+ rc = smc_wr_tx_send(link, pend);
+put_out:
+ smc_wr_tx_link_put(link);
+ return rc;
}
static int smc_llc_cli_rkey_exchange(struct smc_link *link,
}
static int smc_llc_cli_rkey_exchange(struct smc_link *link,
/* Wakeup sndbuf consumers from any context (IRQ or process)
* since there is more data to transmit; usable snd_wnd as max transmit
*/
/* Wakeup sndbuf consumers from any context (IRQ or process)
* since there is more data to transmit; usable snd_wnd as max transmit
*/
-static int _smcr_tx_sndbuf_nonempty(struct smc_connection *conn)
+static int smcr_tx_sndbuf_nonempty(struct smc_connection *conn)
{
struct smc_cdc_producer_flags *pflags = &conn->local_tx_ctrl.prod_flags;
struct smc_link *link = conn->lnk;
{
struct smc_cdc_producer_flags *pflags = &conn->local_tx_ctrl.prod_flags;
struct smc_link *link = conn->lnk;
struct smc_wr_buf *wr_buf;
int rc;
struct smc_wr_buf *wr_buf;
int rc;
+ if (!link || !smc_wr_tx_link_hold(link))
+ return -ENOLINK;
rc = smc_cdc_get_free_slot(conn, link, &wr_buf, &wr_rdma_buf, &pend);
if (rc < 0) {
rc = smc_cdc_get_free_slot(conn, link, &wr_buf, &wr_rdma_buf, &pend);
if (rc < 0) {
+ smc_wr_tx_link_put(link);
if (rc == -EBUSY) {
struct smc_sock *smc =
container_of(conn, struct smc_sock, conn);
if (rc == -EBUSY) {
struct smc_sock *smc =
container_of(conn, struct smc_sock, conn);
out_unlock:
spin_unlock_bh(&conn->send_lock);
out_unlock:
spin_unlock_bh(&conn->send_lock);
- return rc;
-}
-
-static int smcr_tx_sndbuf_nonempty(struct smc_connection *conn)
-{
- struct smc_link *link = conn->lnk;
- int rc = -ENOLINK;
-
- if (!link)
- return rc;
-
- atomic_inc(&link->wr_tx_refcnt);
- if (smc_link_usable(link))
- rc = _smcr_tx_sndbuf_nonempty(conn);
- if (atomic_dec_and_test(&link->wr_tx_refcnt))
- wake_up_all(&link->wr_tx_wait);
+ smc_wr_tx_link_put(link);
atomic_long_set(wr_tx_id, val);
}
atomic_long_set(wr_tx_id, val);
}
+static inline bool smc_wr_tx_link_hold(struct smc_link *link)
+{
+ if (!smc_link_usable(link))
+ return false;
+ atomic_inc(&link->wr_tx_refcnt);
+ return true;
+}
+
+static inline void smc_wr_tx_link_put(struct smc_link *link)
+{
+ if (atomic_dec_and_test(&link->wr_tx_refcnt))
+ wake_up_all(&link->wr_tx_wait);
+}
+
static inline void smc_wr_wakeup_tx_wait(struct smc_link *lnk)
{
wake_up_all(&lnk->wr_tx_wait);
static inline void smc_wr_wakeup_tx_wait(struct smc_link *lnk)
{
wake_up_all(&lnk->wr_tx_wait);