IPoIB/cm: Fix SRQ WR leak

SRQ WR leakage has been observed with IPoIB/CM: e.g. flipping ports on
and off will, with time, leak out all WRs and then all connections
will start getting RNR NAKs.  Fix this in the way suggested by spec:
move the QP being destroyed to the error state, wait for "Last WQE
Reached" event and then post WR on a "drain QP" connected to the same
CQ.  Once we observe a completion on the drain QP, it's safe to call
ib_destroy_qp.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
This commit is contained in:
Michael S. Tsirkin 2007-05-21 15:04:59 +03:00 committed by Roland Dreier
parent 24bd1e4e32
commit 518b1646f8
3 changed files with 211 additions and 36 deletions

View File

@ -132,12 +132,46 @@ struct ipoib_cm_data {
__be32 mtu;
};
/*
* Quoting 10.3.1 Queue Pair and EE Context States:
*
* Note, for QPs that are associated with an SRQ, the Consumer should take the
* QP through the Error State before invoking a Destroy QP or a Modify QP to the
* Reset State. The Consumer may invoke the Destroy QP without first performing
* a Modify QP to the Error State and waiting for the Affiliated Asynchronous
* Last WQE Reached Event. However, if the Consumer does not wait for the
* Affiliated Asynchronous Last WQE Reached Event, then WQE and Data Segment
* leakage may occur. Therefore, it is good programming practice to tear down a
* QP that is associated with an SRQ by using the following process:
*
* - Put the QP in the Error State
* - Wait for the Affiliated Asynchronous Last WQE Reached Event;
* - either:
* drain the CQ by invoking the Poll CQ verb and either wait for CQ
* to be empty or the number of Poll CQ operations has exceeded
* CQ capacity size;
* - or
* post another WR that completes on the same CQ and wait for this
* WR to return as a WC;
* - and then invoke a Destroy QP or Reset QP.
*
* We use the second option and wait for a completion on the
* rx_drain_qp before destroying QPs attached to our SRQ.
*/
enum ipoib_cm_state {
IPOIB_CM_RX_LIVE,
IPOIB_CM_RX_ERROR, /* Ignored by stale task */
IPOIB_CM_RX_FLUSH /* Last WQE Reached event observed */
};
struct ipoib_cm_rx {
struct ib_cm_id *id;
struct ib_qp *qp;
struct list_head list;
struct net_device *dev;
unsigned long jiffies;
enum ipoib_cm_state state;
};
struct ipoib_cm_tx {
@ -165,10 +199,16 @@ struct ipoib_cm_dev_priv {
struct ib_srq *srq;
struct ipoib_cm_rx_buf *srq_ring;
struct ib_cm_id *id;
struct list_head passive_ids;
struct ib_qp *rx_drain_qp; /* generates WR described in 10.3.1 */
struct list_head passive_ids; /* state: LIVE */
struct list_head rx_error_list; /* state: ERROR */
struct list_head rx_flush_list; /* state: FLUSH, drain not started */
struct list_head rx_drain_list; /* state: FLUSH, drain started */
struct list_head rx_reap_list; /* state: FLUSH, drain done */
struct work_struct start_task;
struct work_struct reap_task;
struct work_struct skb_task;
struct work_struct rx_reap_task;
struct delayed_work stale_task;
struct sk_buff_head skb_queue;
struct list_head start_list;

View File

@ -37,6 +37,7 @@
#include <net/dst.h>
#include <net/icmp.h>
#include <linux/icmpv6.h>
#include <linux/delay.h>
#ifdef CONFIG_INFINIBAND_IPOIB_DEBUG_DATA
static int data_debug_level;
@ -62,6 +63,16 @@ struct ipoib_cm_id {
u32 remote_mtu;
};
static struct ib_qp_attr ipoib_cm_err_attr = {
.qp_state = IB_QPS_ERR
};
#define IPOIB_CM_RX_DRAIN_WRID 0x7fffffff
static struct ib_recv_wr ipoib_cm_rx_drain_wr = {
.wr_id = IPOIB_CM_RX_DRAIN_WRID
};
static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
struct ib_cm_event *event);
@ -150,11 +161,44 @@ partial_error:
return NULL;
}
static void ipoib_cm_start_rx_drain(struct ipoib_dev_priv* priv)
{
struct ib_recv_wr *bad_wr;
/* rx_drain_qp send queue depth is 1, so
* make sure we have at most 1 outstanding WR. */
if (list_empty(&priv->cm.rx_flush_list) ||
!list_empty(&priv->cm.rx_drain_list))
return;
if (ib_post_recv(priv->cm.rx_drain_qp, &ipoib_cm_rx_drain_wr, &bad_wr))
ipoib_warn(priv, "failed to post rx_drain wr\n");
list_splice_init(&priv->cm.rx_flush_list, &priv->cm.rx_drain_list);
}
static void ipoib_cm_rx_event_handler(struct ib_event *event, void *ctx)
{
struct ipoib_cm_rx *p = ctx;
struct ipoib_dev_priv *priv = netdev_priv(p->dev);
unsigned long flags;
if (event->event != IB_EVENT_QP_LAST_WQE_REACHED)
return;
spin_lock_irqsave(&priv->lock, flags);
list_move(&p->list, &priv->cm.rx_flush_list);
p->state = IPOIB_CM_RX_FLUSH;
ipoib_cm_start_rx_drain(priv);
spin_unlock_irqrestore(&priv->lock, flags);
}
static struct ib_qp *ipoib_cm_create_rx_qp(struct net_device *dev,
struct ipoib_cm_rx *p)
{
struct ipoib_dev_priv *priv = netdev_priv(dev);
struct ib_qp_init_attr attr = {
.event_handler = ipoib_cm_rx_event_handler,
.send_cq = priv->cq, /* does not matter, we never send anything */
.recv_cq = priv->cq,
.srq = priv->cm.srq,
@ -256,6 +300,7 @@ static int ipoib_cm_req_handler(struct ib_cm_id *cm_id, struct ib_cm_event *even
cm_id->context = p;
p->jiffies = jiffies;
p->state = IPOIB_CM_RX_LIVE;
spin_lock_irq(&priv->lock);
if (list_empty(&priv->cm.passive_ids))
queue_delayed_work(ipoib_workqueue,
@ -277,7 +322,6 @@ static int ipoib_cm_rx_handler(struct ib_cm_id *cm_id,
{
struct ipoib_cm_rx *p;
struct ipoib_dev_priv *priv;
int ret;
switch (event->event) {
case IB_CM_REQ_RECEIVED:
@ -289,20 +333,9 @@ static int ipoib_cm_rx_handler(struct ib_cm_id *cm_id,
case IB_CM_REJ_RECEIVED:
p = cm_id->context;
priv = netdev_priv(p->dev);
spin_lock_irq(&priv->lock);
if (list_empty(&p->list))
ret = 0; /* Connection is going away already. */
else {
list_del_init(&p->list);
ret = -ECONNRESET;
}
spin_unlock_irq(&priv->lock);
if (ret) {
ib_destroy_qp(p->qp);
kfree(p);
return ret;
}
return 0;
if (ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE))
ipoib_warn(priv, "unable to move qp to error state\n");
/* Fall through */
default:
return 0;
}
@ -354,8 +387,15 @@ void ipoib_cm_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
wr_id, wc->status);
if (unlikely(wr_id >= ipoib_recvq_size)) {
ipoib_warn(priv, "cm recv completion event with wrid %d (> %d)\n",
wr_id, ipoib_recvq_size);
if (wr_id == (IPOIB_CM_RX_DRAIN_WRID & ~IPOIB_CM_OP_SRQ)) {
spin_lock_irqsave(&priv->lock, flags);
list_splice_init(&priv->cm.rx_drain_list, &priv->cm.rx_reap_list);
ipoib_cm_start_rx_drain(priv);
queue_work(ipoib_workqueue, &priv->cm.rx_reap_task);
spin_unlock_irqrestore(&priv->lock, flags);
} else
ipoib_warn(priv, "cm recv completion event with wrid %d (> %d)\n",
wr_id, ipoib_recvq_size);
return;
}
@ -374,9 +414,9 @@ void ipoib_cm_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
if (p && time_after_eq(jiffies, p->jiffies + IPOIB_CM_RX_UPDATE_TIME)) {
spin_lock_irqsave(&priv->lock, flags);
p->jiffies = jiffies;
/* Move this entry to list head, but do
* not re-add it if it has been removed. */
if (!list_empty(&p->list))
/* Move this entry to list head, but do not re-add it
* if it has been moved out of list. */
if (p->state == IPOIB_CM_RX_LIVE)
list_move(&p->list, &priv->cm.passive_ids);
spin_unlock_irqrestore(&priv->lock, flags);
}
@ -583,17 +623,43 @@ static void ipoib_cm_tx_completion(struct ib_cq *cq, void *tx_ptr)
int ipoib_cm_dev_open(struct net_device *dev)
{
struct ipoib_dev_priv *priv = netdev_priv(dev);
struct ib_qp_init_attr qp_init_attr = {
.send_cq = priv->cq, /* does not matter, we never send anything */
.recv_cq = priv->cq,
.cap.max_send_wr = 1, /* FIXME: 0 Seems not to work */
.cap.max_send_sge = 1, /* FIXME: 0 Seems not to work */
.cap.max_recv_wr = 1,
.cap.max_recv_sge = 1, /* FIXME: 0 Seems not to work */
.sq_sig_type = IB_SIGNAL_ALL_WR,
.qp_type = IB_QPT_UC,
};
int ret;
if (!IPOIB_CM_SUPPORTED(dev->dev_addr))
return 0;
priv->cm.rx_drain_qp = ib_create_qp(priv->pd, &qp_init_attr);
if (IS_ERR(priv->cm.rx_drain_qp)) {
printk(KERN_WARNING "%s: failed to create CM ID\n", priv->ca->name);
ret = PTR_ERR(priv->cm.rx_drain_qp);
return ret;
}
/*
* We put the QP in error state directly. This way, a "flush
* error" WC will be immediately generated for each WR we post.
*/
ret = ib_modify_qp(priv->cm.rx_drain_qp, &ipoib_cm_err_attr, IB_QP_STATE);
if (ret) {
ipoib_warn(priv, "failed to modify drain QP to error: %d\n", ret);
goto err_qp;
}
priv->cm.id = ib_create_cm_id(priv->ca, ipoib_cm_rx_handler, dev);
if (IS_ERR(priv->cm.id)) {
printk(KERN_WARNING "%s: failed to create CM ID\n", priv->ca->name);
ret = PTR_ERR(priv->cm.id);
priv->cm.id = NULL;
return ret;
goto err_cm;
}
ret = ib_cm_listen(priv->cm.id, cpu_to_be64(IPOIB_CM_IETF_ID | priv->qp->qp_num),
@ -601,35 +667,79 @@ int ipoib_cm_dev_open(struct net_device *dev)
if (ret) {
printk(KERN_WARNING "%s: failed to listen on ID 0x%llx\n", priv->ca->name,
IPOIB_CM_IETF_ID | priv->qp->qp_num);
ib_destroy_cm_id(priv->cm.id);
priv->cm.id = NULL;
return ret;
goto err_listen;
}
return 0;
err_listen:
ib_destroy_cm_id(priv->cm.id);
err_cm:
priv->cm.id = NULL;
err_qp:
ib_destroy_qp(priv->cm.rx_drain_qp);
return ret;
}
void ipoib_cm_dev_stop(struct net_device *dev)
{
struct ipoib_dev_priv *priv = netdev_priv(dev);
struct ipoib_cm_rx *p;
struct ipoib_cm_rx *p, *n;
unsigned long begin;
LIST_HEAD(list);
int ret;
if (!IPOIB_CM_SUPPORTED(dev->dev_addr) || !priv->cm.id)
return;
ib_destroy_cm_id(priv->cm.id);
priv->cm.id = NULL;
spin_lock_irq(&priv->lock);
while (!list_empty(&priv->cm.passive_ids)) {
p = list_entry(priv->cm.passive_ids.next, typeof(*p), list);
list_del_init(&p->list);
list_move(&p->list, &priv->cm.rx_error_list);
p->state = IPOIB_CM_RX_ERROR;
spin_unlock_irq(&priv->lock);
ret = ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE);
if (ret)
ipoib_warn(priv, "unable to move qp to error state: %d\n", ret);
spin_lock_irq(&priv->lock);
}
/* Wait for all RX to be drained */
begin = jiffies;
while (!list_empty(&priv->cm.rx_error_list) ||
!list_empty(&priv->cm.rx_flush_list) ||
!list_empty(&priv->cm.rx_drain_list)) {
if (!time_after(jiffies, begin + 5 * HZ)) {
ipoib_warn(priv, "RX drain timing out\n");
/*
* assume the HW is wedged and just free up everything.
*/
list_splice_init(&priv->cm.rx_flush_list, &list);
list_splice_init(&priv->cm.rx_error_list, &list);
list_splice_init(&priv->cm.rx_drain_list, &list);
break;
}
spin_unlock_irq(&priv->lock);
msleep(1);
spin_lock_irq(&priv->lock);
}
list_splice_init(&priv->cm.rx_reap_list, &list);
spin_unlock_irq(&priv->lock);
list_for_each_entry_safe(p, n, &list, list) {
ib_destroy_cm_id(p->id);
ib_destroy_qp(p->qp);
kfree(p);
spin_lock_irq(&priv->lock);
}
spin_unlock_irq(&priv->lock);
ib_destroy_qp(priv->cm.rx_drain_qp);
cancel_delayed_work(&priv->cm.stale_task);
}
@ -1079,24 +1189,44 @@ void ipoib_cm_skb_too_long(struct net_device* dev, struct sk_buff *skb,
queue_work(ipoib_workqueue, &priv->cm.skb_task);
}
static void ipoib_cm_rx_reap(struct work_struct *work)
{
struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
cm.rx_reap_task);
struct ipoib_cm_rx *p, *n;
LIST_HEAD(list);
spin_lock_irq(&priv->lock);
list_splice_init(&priv->cm.rx_reap_list, &list);
spin_unlock_irq(&priv->lock);
list_for_each_entry_safe(p, n, &list, list) {
ib_destroy_cm_id(p->id);
ib_destroy_qp(p->qp);
kfree(p);
}
}
static void ipoib_cm_stale_task(struct work_struct *work)
{
struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
cm.stale_task.work);
struct ipoib_cm_rx *p;
int ret;
spin_lock_irq(&priv->lock);
while (!list_empty(&priv->cm.passive_ids)) {
/* List if sorted by LRU, start from tail,
/* List is sorted by LRU, start from tail,
* stop when we see a recently used entry */
p = list_entry(priv->cm.passive_ids.prev, typeof(*p), list);
if (time_before_eq(jiffies, p->jiffies + IPOIB_CM_RX_TIMEOUT))
break;
list_del_init(&p->list);
list_move(&p->list, &priv->cm.rx_error_list);
p->state = IPOIB_CM_RX_ERROR;
spin_unlock_irq(&priv->lock);
ib_destroy_cm_id(p->id);
ib_destroy_qp(p->qp);
kfree(p);
ret = ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE);
if (ret)
ipoib_warn(priv, "unable to move qp to error state: %d\n", ret);
spin_lock_irq(&priv->lock);
}
@ -1164,9 +1294,14 @@ int ipoib_cm_dev_init(struct net_device *dev)
INIT_LIST_HEAD(&priv->cm.passive_ids);
INIT_LIST_HEAD(&priv->cm.reap_list);
INIT_LIST_HEAD(&priv->cm.start_list);
INIT_LIST_HEAD(&priv->cm.rx_error_list);
INIT_LIST_HEAD(&priv->cm.rx_flush_list);
INIT_LIST_HEAD(&priv->cm.rx_drain_list);
INIT_LIST_HEAD(&priv->cm.rx_reap_list);
INIT_WORK(&priv->cm.start_task, ipoib_cm_tx_start);
INIT_WORK(&priv->cm.reap_task, ipoib_cm_tx_reap);
INIT_WORK(&priv->cm.skb_task, ipoib_cm_skb_reap);
INIT_WORK(&priv->cm.rx_reap_task, ipoib_cm_rx_reap);
INIT_DELAYED_WORK(&priv->cm.stale_task, ipoib_cm_stale_task);
skb_queue_head_init(&priv->cm.skb_queue);

View File

@ -173,7 +173,7 @@ int ipoib_transport_dev_init(struct net_device *dev, struct ib_device *ca)
size = ipoib_sendq_size + ipoib_recvq_size + 1;
ret = ipoib_cm_dev_init(dev);
if (!ret)
size += ipoib_recvq_size;
size += ipoib_recvq_size + 1 /* 1 extra for rx_drain_qp */;
priv->cq = ib_create_cq(priv->ca, ipoib_ib_completion, NULL, dev, size, 0);
if (IS_ERR(priv->cq)) {