From: Jacob Keller <jacob.e.keller@xxxxxxxxx>
This patch has been added to the 3.12 stable tree. If you have any
objections, please let us know.
===============
commit 27d9ce4fd0e2e75c2907f6d3dc0487012a3e4298 upstream.
ixgbe_napi_disable_all calls napi_disable on each queue, however the busy
polling code introduced a local_bh_disable()d context around the napi_disable.
The original author did not realize that napi_disable might sleep, which would
cause a sleep while atomic BUG. In addition, on a single processor system, the
ixgbe_qv_lock_napi loop shouldn't have to mdelay. This patch adds an
ixgbe_qv_disable along with a new IXGBE_QV_STATE_DISABLED bit, which it uses to
indicate to the poll and napi routines that the q_vector has been disabled. Now
the ixgbe_napi_disable_all function will wait until all pending work has been
finished and prevent any future work from being started.
Signed-off-by: Jacob Keller <jacob.e.keller@xxxxxxxxx>
Cc: Eliezer Tamir <eliezer.tamir@xxxxxxxxxxxxxxx>
Cc: Alexander Duyck <alexander.duyck@xxxxxxxxx>
Cc: Hyong-Youb Kim <hykim@xxxxxxxx>
Cc: Amir Vadai <amirv@xxxxxxxxxxxx>
Cc: Dmitry Kravkov <dmitry@xxxxxxxxxxxx>
Tested-by: Phil Schmitt <phillip.j.schmitt@xxxxxxxxx>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/net/ethernet/intel/ixgbe/ixgbe.h | 48 ++++++++++++++++++++-------
drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 6 ++--
2 files changed, 38 insertions(+), 16 deletions(-)
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
index 0ac6b11c6e4e..4506f8a15c8a 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
@@ -369,11 +369,13 @@ struct ixgbe_q_vector {
#ifdef CONFIG_NET_RX_BUSY_POLL
unsigned int state;
#define IXGBE_QV_STATE_IDLE 0
-#define IXGBE_QV_STATE_NAPI 1 /* NAPI owns this QV */
-#define IXGBE_QV_STATE_POLL 2 /* poll owns this QV */
-#define IXGBE_QV_LOCKED (IXGBE_QV_STATE_NAPI | IXGBE_QV_STATE_POLL)
-#define IXGBE_QV_STATE_NAPI_YIELD 4 /* NAPI yielded this QV */
-#define IXGBE_QV_STATE_POLL_YIELD 8 /* poll yielded this QV */
+#define IXGBE_QV_STATE_NAPI 1 /* NAPI owns this QV */
+#define IXGBE_QV_STATE_POLL 2 /* poll owns this QV */
+#define IXGBE_QV_STATE_DISABLED 4 /* QV is disabled */
+#define IXGBE_QV_OWNED (IXGBE_QV_STATE_NAPI | IXGBE_QV_STATE_POLL)
+#define IXGBE_QV_LOCKED (IXGBE_QV_OWNED | IXGBE_QV_STATE_DISABLED)
+#define IXGBE_QV_STATE_NAPI_YIELD 8 /* NAPI yielded this QV */
+#define IXGBE_QV_STATE_POLL_YIELD 16 /* poll yielded this QV */
#define IXGBE_QV_YIELD (IXGBE_QV_STATE_NAPI_YIELD | IXGBE_QV_STATE_POLL_YIELD)
#define IXGBE_QV_USER_PEND (IXGBE_QV_STATE_POLL | IXGBE_QV_STATE_POLL_YIELD)
spinlock_t lock;
@@ -394,7 +396,7 @@ static inline void ixgbe_qv_init_lock(struct ixgbe_q_vector *q_vector)
static inline bool ixgbe_qv_lock_napi(struct ixgbe_q_vector *q_vector)
{
int rc = true;
- spin_lock(&q_vector->lock);
+ spin_lock_bh(&q_vector->lock);
if (q_vector->state & IXGBE_QV_LOCKED) {
WARN_ON(q_vector->state & IXGBE_QV_STATE_NAPI);
q_vector->state |= IXGBE_QV_STATE_NAPI_YIELD;
@@ -405,7 +407,7 @@ static inline bool ixgbe_qv_lock_napi(struct ixgbe_q_vector *q_vector)
} else
/* we don't care if someone yielded */
q_vector->state = IXGBE_QV_STATE_NAPI;
- spin_unlock(&q_vector->lock);
+ spin_unlock_bh(&q_vector->lock);
return rc;
}
@@ -413,14 +415,15 @@ static inline bool ixgbe_qv_lock_napi(struct ixgbe_q_vector *q_vector)
static inline bool ixgbe_qv_unlock_napi(struct ixgbe_q_vector *q_vector)
{
int rc = false;
- spin_lock(&q_vector->lock);
+ spin_lock_bh(&q_vector->lock);
WARN_ON(q_vector->state & (IXGBE_QV_STATE_POLL |
IXGBE_QV_STATE_NAPI_YIELD));
if (q_vector->state & IXGBE_QV_STATE_POLL_YIELD)
rc = true;
- q_vector->state = IXGBE_QV_STATE_IDLE;
- spin_unlock(&q_vector->lock);
+ /* will reset state to idle, unless QV is disabled */
+ q_vector->state &= IXGBE_QV_STATE_DISABLED;
+ spin_unlock_bh(&q_vector->lock);
return rc;
}
@@ -451,7 +454,8 @@ static inline bool ixgbe_qv_unlock_poll(struct ixgbe_q_vector *q_vector)
if (q_vector->state & IXGBE_QV_STATE_POLL_YIELD)
rc = true;
- q_vector->state = IXGBE_QV_STATE_IDLE;
+ /* will reset state to idle, unless QV is disabled */
+ q_vector->state &= IXGBE_QV_STATE_DISABLED;
spin_unlock_bh(&q_vector->lock);
return rc;
}
@@ -459,9 +463,23 @@ static inline bool ixgbe_qv_unlock_poll(struct ixgbe_q_vector *q_vector)
/* true if a socket is polling, even if it did not get the lock */
static inline bool ixgbe_qv_ll_polling(struct ixgbe_q_vector *q_vector)
{
- WARN_ON(!(q_vector->state & IXGBE_QV_LOCKED));
+ WARN_ON(!(q_vector->state & IXGBE_QV_OWNED));
return q_vector->state & IXGBE_QV_USER_PEND;
}
+
+/* false if QV is currently owned */
+static inline bool ixgbe_qv_disable(struct ixgbe_q_vector *q_vector)
+{
+ int rc = true;
+ spin_lock_bh(&q_vector->lock);
+ if (q_vector->state & IXGBE_QV_OWNED)
+ rc = false;
+ q_vector->state |= IXGBE_QV_STATE_DISABLED;
+ spin_unlock_bh(&q_vector->lock);
+
+ return rc;
+}
+
#else /* CONFIG_NET_RX_BUSY_POLL */
static inline void ixgbe_qv_init_lock(struct ixgbe_q_vector *q_vector)
{
@@ -491,6 +509,12 @@ static inline bool ixgbe_qv_ll_polling(struct ixgbe_q_vector *q_vector)
{
return false;
}
+
+static inline bool ixgbe_qv_disable(struct ixgbe_q_vector *q_vector)
+{
+ return true;
+}
+
#endif /* CONFIG_NET_RX_BUSY_POLL */
#ifdef CONFIG_IXGBE_HWMON
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index bf046e14ceb5..a178a9caa763 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -3893,15 +3893,13 @@ static void ixgbe_napi_disable_all(struct ixgbe_adapter *adapter)
{
int q_idx;
- local_bh_disable(); /* for ixgbe_qv_lock_napi() */
for (q_idx = 0; q_idx < adapter->num_q_vectors; q_idx++) {
napi_disable(&adapter->q_vector[q_idx]->napi);
- while (!ixgbe_qv_lock_napi(adapter->q_vector[q_idx])) {
+ while (!ixgbe_qv_disable(adapter->q_vector[q_idx])) {
pr_info("QV %d locked\n", q_idx);
- mdelay(1);
+ usleep_range(1000, 20000);
}
}
- local_bh_enable();
}
#ifdef CONFIG_IXGBE_DCB
--
2.0.4
--
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