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>
This commit is contained in:
Vladislav Zolotarov 2010-07-21 05:59:01 +00:00 committed by David S. Miller
parent 573201f36f
commit a13773a53f
2 changed files with 11 additions and 4 deletions

View File

@ -1062,6 +1062,10 @@ struct bnx2x {
/* 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;

View File

@ -4849,16 +4849,18 @@ static const struct {
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 @@ static int __devinit bnx2x_init_bp(struct bnx2x *bp)
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