bnx2x: Protect a SM state change
Bug fix: Protect the statistics state machine state update with a
spinlock. Otherwise there was a race condition that would cause the
statistics to stay enabled despite the fact that they were disabled in
the LINK_DOWN event handler.
Signed-off-by: Vladislav Zolotarov <vladz@broadcom.com>
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bnx2x.h b/drivers/net/bnx2x.h
index 8bd2368..bb0872a 100644
--- a/drivers/net/bnx2x.h
+++ b/drivers/net/bnx2x.h
@@ -1062,6 +1062,10 @@
/* used to synchronize stats collecting */
int stats_state;
+
+ /* used for synchronization of concurrent threads statistics handling */
+ spinlock_t stats_lock;
+
/* used by dmae command loader */
struct dmae_command stats_dmae;
int executer_idx;
diff --git a/drivers/net/bnx2x_main.c b/drivers/net/bnx2x_main.c
index 57ff5b3..3dc876c 100644
--- a/drivers/net/bnx2x_main.c
+++ b/drivers/net/bnx2x_main.c
@@ -4849,16 +4849,18 @@
static void bnx2x_stats_handle(struct bnx2x *bp, enum bnx2x_stats_event event)
{
- enum bnx2x_stats_state state = bp->stats_state;
+ enum bnx2x_stats_state state;
if (unlikely(bp->panic))
return;
- bnx2x_stats_stm[state][event].action(bp);
+ /* Protect a state change flow */
+ spin_lock_bh(&bp->stats_lock);
+ state = bp->stats_state;
bp->stats_state = bnx2x_stats_stm[state][event].next_state;
+ spin_unlock_bh(&bp->stats_lock);
- /* Make sure the state has been "changed" */
- smp_wmb();
+ bnx2x_stats_stm[state][event].action(bp);
if ((event != STATS_EVENT_UPDATE) || netif_msg_timer(bp))
DP(BNX2X_MSG_STATS, "state %d -> event %d -> state %d\n",
@@ -9908,6 +9910,7 @@
mutex_init(&bp->port.phy_mutex);
mutex_init(&bp->fw_mb_mutex);
+ spin_lock_init(&bp->stats_lock);
#ifdef BCM_CNIC
mutex_init(&bp->cnic_mutex);
#endif