Running uperf tests with SMCD on LPARs results in corrupted cursors.
SMCD cursors should be treated atomically to fix cursor corruption.
Signed-off-by: Ursula Braun <ubraun@xxxxxxxxxxxxx>
---
net/smc/smc_cdc.c | 24 ++++++++++++++----------
net/smc/smc_cdc.h | 56 ++++++++++++++++++++++++++++++++++++++++++-------------
2 files changed, 57 insertions(+), 23 deletions(-)
diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c
index ed5dcf03fe0b..18c047c155fd 100644
--- a/net/smc/smc_cdc.c
+++ b/net/smc/smc_cdc.c
@@ -177,23 +177,24 @@ void smc_cdc_tx_dismiss_slots(struct smc_connection *conn)
int smcd_cdc_msg_send(struct smc_connection *conn)
{
struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
+ union smc_host_cursor curs;
struct smcd_cdc_msg cdc;
int rc, diff;
memset(&cdc, 0, sizeof(cdc));
cdc.common.type = SMC_CDC_MSG_TYPE;
- cdc.prod_wrap = conn->local_tx_ctrl.prod.wrap;
- cdc.prod_count = conn->local_tx_ctrl.prod.count;
-
- cdc.cons_wrap = conn->local_tx_ctrl.cons.wrap;
- cdc.cons_count = conn->local_tx_ctrl.cons.count;
- cdc.prod_flags = conn->local_tx_ctrl.prod_flags;
- cdc.conn_state_flags = conn->local_tx_ctrl.conn_state_flags;
+ curs.acurs.counter = atomic64_read(&conn->local_tx_ctrl.prod.acurs);
+ cdc.prod.wrap = curs.wrap;
+ cdc.prod.count = curs.count;
+ curs.acurs.counter = atomic64_read(&conn->local_tx_ctrl.cons.acurs);
+ cdc.cons.wrap = curs.wrap;
+ cdc.cons.count = curs.count;
+ cdc.cons.prod_flags = conn->local_tx_ctrl.prod_flags;
+ cdc.cons.conn_state_flags = conn->local_tx_ctrl.conn_state_flags;
rc = smcd_tx_ism_write(conn, &cdc, sizeof(cdc), 0, 1);
if (rc)
return rc;
- smc_curs_copy(&conn->rx_curs_confirmed, &conn->local_tx_ctrl.cons,
- conn);
+ smc_curs_copy(&conn->rx_curs_confirmed, &curs, conn);
/* Calculate transmitted data and increment free send buffer space */
diff = smc_curs_diff(conn->sndbuf_desc->len, &conn->tx_curs_fin,
&conn->tx_curs_sent);
@@ -331,13 +332,16 @@ static void smc_cdc_msg_recv(struct smc_sock *smc, struct smc_cdc_msg *cdc)
static void smcd_cdc_rx_tsklet(unsigned long data)
{
struct smc_connection *conn = (struct smc_connection *)data;
+ struct smcd_cdc_msg *data_cdc;
struct smcd_cdc_msg cdc;
struct smc_sock *smc;
if (!conn)
return;
- memcpy(&cdc, conn->rmb_desc->cpu_addr, sizeof(cdc));
+ data_cdc = (struct smcd_cdc_msg *)conn->rmb_desc->cpu_addr;
+ smcd_curs_copy(&cdc.prod, &data_cdc->prod, conn);
+ smcd_curs_copy(&cdc.cons, &data_cdc->cons, conn);
smc = container_of(conn, struct smc_sock, conn);
smc_cdc_msg_recv(smc, (struct smc_cdc_msg *)&cdc);
}
diff --git a/net/smc/smc_cdc.h b/net/smc/smc_cdc.h
index 934df4473a7c..b9772ab77ddf 100644
--- a/net/smc/smc_cdc.h
+++ b/net/smc/smc_cdc.h
@@ -50,17 +50,27 @@ struct smc_cdc_msg {
u8 reserved[18];
} __packed; /* format defined in RFC7609 */
+/* SMC-D cursor format */
+union smcd_cdc_cursor {
+ struct {
+ u16 wrap;
+ u32 count;
+ struct smc_cdc_producer_flags prod_flags;
+ struct smc_cdc_conn_state_flags conn_state_flags;
+ } __packed;
+#ifdef KERNEL_HAS_ATOMIC64
+ atomic64_t acurs; /* for atomic processing */
+#else
+ u64 acurs; /* for atomic processing */
+#endif
+} __aligned(8);
+
/* CDC message for SMC-D */
struct smcd_cdc_msg {
struct smc_wr_rx_hdr common; /* Type = 0xFE */
u8 res1[7];
- u16 prod_wrap;
- u32 prod_count;
- u8 res2[2];
- u16 cons_wrap;
- u32 cons_count;
- struct smc_cdc_producer_flags prod_flags;
- struct smc_cdc_conn_state_flags conn_state_flags;
+ union smcd_cdc_cursor prod;
+ union smcd_cdc_cursor cons;
u8 res3[8];
} __packed;
@@ -135,6 +145,21 @@ static inline void smc_curs_copy_net(union smc_cdc_cursor *tgt,
#endif
}
+static inline void smcd_curs_copy(union smcd_cdc_cursor *tgt,
+ union smcd_cdc_cursor *src,
+ struct smc_connection *conn)
+{
+#ifndef KERNEL_HAS_ATOMIC64
+ unsigned long flags;
+
+ spin_lock_irqsave(&conn->acurs_lock, flags);
+ tgt->acurs = src->acurs;
+ spin_unlock_irqrestore(&conn->acurs_lock, flags);
+#else
+ atomic64_set(&tgt->acurs, atomic64_read(&src->acurs));
+#endif
+}
+
/* calculate cursor difference between old and new, where old <= new */
static inline int smc_curs_diff(unsigned int size,
union smc_host_cursor *old,
@@ -222,12 +247,17 @@ static inline void smcr_cdc_msg_to_host(struct smc_host_cdc_msg *local,
static inline void smcd_cdc_msg_to_host(struct smc_host_cdc_msg *local,
struct smcd_cdc_msg *peer)
{
- local->prod.wrap = peer->prod_wrap;
- local->prod.count = peer->prod_count;
- local->cons.wrap = peer->cons_wrap;
- local->cons.count = peer->cons_count;
- local->prod_flags = peer->prod_flags;
- local->conn_state_flags = peer->conn_state_flags;
+ union smc_host_cursor temp;
+
+ temp.wrap = peer->prod.wrap;
+ temp.count = peer->prod.count;
+ atomic64_set(&local->prod.acurs, atomic64_read(&temp.acurs));
+
+ temp.wrap = peer->cons.wrap;
+ temp.count = peer->cons.count;
+ atomic64_set(&local->cons.acurs, atomic64_read(&temp.acurs));
+ local->prod_flags = peer->cons.prod_flags;
+ local->conn_state_flags = peer->cons.conn_state_flags;
}
static inline void smc_cdc_msg_to_host(struct smc_host_cdc_msg *local,
--
2.16.4
