staging: qlge: Refill empty buffer queues from wq

When operating at mtu 9000, qlge does order-1 allocations for rx buffers in
atomic context. This is especially unreliable when free memory is low or
fragmented. Add an approach similar to commit 3161e453e4 ("virtio: net
refill on out-of-memory") to qlge so that the device doesn't lock up if
there are allocation failures.

Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Link: https://lore.kernel.org/r/20190927101210.23856-18-bpoirier@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Benjamin Poirier 2019-09-27 19:12:11 +09:00 committed by Greg Kroah-Hartman
parent 6e9c52b920
commit b91fec1ecf
3 changed files with 72 additions and 19 deletions

View File

@ -1,6 +1,3 @@
* reception stalls permanently (until admin intervention) if the rx buffer
queues become empty because of allocation failures (ex. under memory
pressure)
* commit 7c734359d350 ("qlge: Size RX buffers based on MTU.", v2.6.33-rc1)
introduced dead code in the receive routines, which should be rewritten
anyways by the admission of the author himself, see the comment above

View File

@ -1452,6 +1452,13 @@ struct qlge_bq {
#define QLGE_BQ_WRAP(index) ((index) & (QLGE_BQ_LEN - 1))
#define QLGE_BQ_HW_OWNED(bq) \
({ \
typeof(bq) _bq = bq; \
QLGE_BQ_WRAP(QLGE_BQ_ALIGN((_bq)->next_to_use) - \
(_bq)->next_to_clean); \
})
struct rx_ring {
struct cqicb cqicb; /* The chip's completion queue init control block. */
@ -1479,6 +1486,7 @@ struct rx_ring {
/* Misc. handler elements. */
u32 irq; /* Which vector this ring is assigned. */
u32 cpu; /* Which CPU this should run on. */
struct delayed_work refill_work;
char name[IFNAMSIZ + 5];
struct napi_struct napi;
u8 reserved;

View File

@ -1029,7 +1029,7 @@ static const char * const bq_type_name[] = {
/* return 0 or negative error */
static int qlge_refill_sb(struct rx_ring *rx_ring,
struct qlge_bq_desc *sbq_desc)
struct qlge_bq_desc *sbq_desc, gfp_t gfp)
{
struct ql_adapter *qdev = rx_ring->qdev;
struct sk_buff *skb;
@ -1041,7 +1041,7 @@ static int qlge_refill_sb(struct rx_ring *rx_ring,
"ring %u sbq: getting new skb for index %d.\n",
rx_ring->cq_id, sbq_desc->index);
skb = netdev_alloc_skb(qdev->ndev, SMALL_BUFFER_SIZE);
skb = __netdev_alloc_skb(qdev->ndev, SMALL_BUFFER_SIZE, gfp);
if (!skb)
return -ENOMEM;
skb_reserve(skb, QLGE_SB_PAD);
@ -1062,7 +1062,7 @@ static int qlge_refill_sb(struct rx_ring *rx_ring,
/* return 0 or negative error */
static int qlge_refill_lb(struct rx_ring *rx_ring,
struct qlge_bq_desc *lbq_desc)
struct qlge_bq_desc *lbq_desc, gfp_t gfp)
{
struct ql_adapter *qdev = rx_ring->qdev;
struct qlge_page_chunk *master_chunk = &rx_ring->master_chunk;
@ -1071,8 +1071,7 @@ static int qlge_refill_lb(struct rx_ring *rx_ring,
struct page *page;
dma_addr_t dma_addr;
page = alloc_pages(__GFP_COMP | GFP_ATOMIC,
qdev->lbq_buf_order);
page = alloc_pages(gfp | __GFP_COMP, qdev->lbq_buf_order);
if (unlikely(!page))
return -ENOMEM;
dma_addr = pci_map_page(qdev->pdev, page, 0,
@ -1109,33 +1108,33 @@ static int qlge_refill_lb(struct rx_ring *rx_ring,
return 0;
}
static void qlge_refill_bq(struct qlge_bq *bq)
/* return 0 or negative error */
static int qlge_refill_bq(struct qlge_bq *bq, gfp_t gfp)
{
struct rx_ring *rx_ring = QLGE_BQ_CONTAINER(bq);
struct ql_adapter *qdev = rx_ring->qdev;
struct qlge_bq_desc *bq_desc;
int refill_count;
int retval;
int i;
refill_count = QLGE_BQ_WRAP(QLGE_BQ_ALIGN(bq->next_to_clean - 1) -
bq->next_to_use);
if (!refill_count)
return;
return 0;
i = bq->next_to_use;
bq_desc = &bq->queue[i];
i -= QLGE_BQ_LEN;
do {
int retval;
netif_printk(qdev, rx_status, KERN_DEBUG, qdev->ndev,
"ring %u %s: try cleaning idx %d\n",
rx_ring->cq_id, bq_type_name[bq->type], i);
if (bq->type == QLGE_SB)
retval = qlge_refill_sb(rx_ring, bq_desc);
retval = qlge_refill_sb(rx_ring, bq_desc, gfp);
else
retval = qlge_refill_lb(rx_ring, bq_desc);
retval = qlge_refill_lb(rx_ring, bq_desc, gfp);
if (retval < 0) {
netif_err(qdev, ifup, qdev->ndev,
"ring %u %s: Could not get a page chunk, idx %d\n",
@ -1163,12 +1162,52 @@ static void qlge_refill_bq(struct qlge_bq *bq)
}
bq->next_to_use = i;
}
return retval;
}
static void ql_update_buffer_queues(struct rx_ring *rx_ring)
static void ql_update_buffer_queues(struct rx_ring *rx_ring, gfp_t gfp,
unsigned long delay)
{
qlge_refill_bq(&rx_ring->sbq);
qlge_refill_bq(&rx_ring->lbq);
bool sbq_fail, lbq_fail;
sbq_fail = !!qlge_refill_bq(&rx_ring->sbq, gfp);
lbq_fail = !!qlge_refill_bq(&rx_ring->lbq, gfp);
/* Minimum number of buffers needed to be able to receive at least one
* frame of any format:
* sbq: 1 for header + 1 for data
* lbq: mtu 9000 / lb size
* Below this, the queue might stall.
*/
if ((sbq_fail && QLGE_BQ_HW_OWNED(&rx_ring->sbq) < 2) ||
(lbq_fail && QLGE_BQ_HW_OWNED(&rx_ring->lbq) <
DIV_ROUND_UP(9000, LARGE_BUFFER_MAX_SIZE)))
/* Allocations can take a long time in certain cases (ex.
* reclaim). Therefore, use a workqueue for long-running
* work items.
*/
queue_delayed_work_on(smp_processor_id(), system_long_wq,
&rx_ring->refill_work, delay);
}
static void qlge_slow_refill(struct work_struct *work)
{
struct rx_ring *rx_ring = container_of(work, struct rx_ring,
refill_work.work);
struct napi_struct *napi = &rx_ring->napi;
napi_disable(napi);
ql_update_buffer_queues(rx_ring, GFP_KERNEL, HZ / 2);
napi_enable(napi);
local_bh_disable();
/* napi_disable() might have prevented incomplete napi work from being
* rescheduled.
*/
napi_schedule(napi);
/* trigger softirq processing */
local_bh_enable();
}
/* Unmaps tx buffers. Can be called from send() if a pci mapping
@ -2168,7 +2207,7 @@ static int ql_clean_inbound_rx_ring(struct rx_ring *rx_ring, int budget)
if (count == budget)
break;
}
ql_update_buffer_queues(rx_ring);
ql_update_buffer_queues(rx_ring, GFP_ATOMIC, 0);
ql_write_cq_idx(rx_ring);
return count;
}
@ -2778,7 +2817,8 @@ static void ql_alloc_rx_buffers(struct ql_adapter *qdev)
int i;
for (i = 0; i < qdev->rss_ring_count; i++)
ql_update_buffer_queues(&qdev->rx_ring[i]);
ql_update_buffer_queues(&qdev->rx_ring[i], GFP_KERNEL,
HZ / 2);
}
static int qlge_init_bq(struct qlge_bq *bq)
@ -3883,6 +3923,7 @@ static int ql_get_adapter_resources(struct ql_adapter *qdev)
static int qlge_close(struct net_device *ndev)
{
struct ql_adapter *qdev = netdev_priv(ndev);
int i;
/* If we hit pci_channel_io_perm_failure
* failure condition, then we already
@ -3900,6 +3941,11 @@ static int qlge_close(struct net_device *ndev)
*/
while (!test_bit(QL_ADAPTER_UP, &qdev->flags))
msleep(1);
/* Make sure refill_work doesn't re-enable napi */
for (i = 0; i < qdev->rss_ring_count; i++)
cancel_delayed_work_sync(&qdev->rx_ring[i].refill_work);
ql_adapter_down(qdev);
ql_release_adapter_resources(qdev);
return 0;
@ -3966,6 +4012,8 @@ static int ql_configure_rings(struct ql_adapter *qdev)
rx_ring->cq_len * sizeof(struct ql_net_rsp_iocb);
rx_ring->lbq.type = QLGE_LB;
rx_ring->sbq.type = QLGE_SB;
INIT_DELAYED_WORK(&rx_ring->refill_work,
&qlge_slow_refill);
} else {
/*
* Outbound queue handles outbound completions only.