Commit 5a85e737 authored by Eliezer Tamir's avatar Eliezer Tamir Committed by David S. Miller
Browse files

ixgbe: add support for ndo_ll_poll



Add the ixgbe driver code implementing ndo_ll_poll.
Adds ndo_ll_poll method and locking between it and the napi poll.
When receiving a packet we use skb_mark_ll to record the napi it came from.
Add each napi to the napi_hash right after netif_napi_add().
Signed-off-by: default avatarAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: default avatarJesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: default avatarEliezer Tamir <eliezer.tamir@linux.intel.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d30e383b
......@@ -52,6 +52,8 @@
#include <linux/dca.h>
#endif
#include <net/ll_poll.h>
/* common prefix used by pr_<> macros */
#undef pr_fmt
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
......@@ -356,9 +358,127 @@ struct ixgbe_q_vector {
struct rcu_head rcu; /* to avoid race with update stats on free */
char name[IFNAMSIZ + 9];
#ifdef CONFIG_NET_LL_RX_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_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;
#endif /* CONFIG_NET_LL_RX_POLL */
/* for dynamic allocation of rings associated with this q_vector */
struct ixgbe_ring ring[0] ____cacheline_internodealigned_in_smp;
};
#ifdef CONFIG_NET_LL_RX_POLL
static inline void ixgbe_qv_init_lock(struct ixgbe_q_vector *q_vector)
{
spin_lock_init(&q_vector->lock);
q_vector->state = IXGBE_QV_STATE_IDLE;
}
/* called from the device poll routine to get ownership of a q_vector */
static inline bool ixgbe_qv_lock_napi(struct ixgbe_q_vector *q_vector)
{
int rc = true;
spin_lock(&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;
rc = false;
} else
/* we don't care if someone yielded */
q_vector->state = IXGBE_QV_STATE_NAPI;
spin_unlock(&q_vector->lock);
return rc;
}
/* returns true is someone tried to get the qv while napi had it */
static inline bool ixgbe_qv_unlock_napi(struct ixgbe_q_vector *q_vector)
{
int rc = false;
spin_lock(&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);
return rc;
}
/* called from ixgbe_low_latency_poll() */
static inline bool ixgbe_qv_lock_poll(struct ixgbe_q_vector *q_vector)
{
int rc = true;
spin_lock_bh(&q_vector->lock);
if ((q_vector->state & IXGBE_QV_LOCKED)) {
q_vector->state |= IXGBE_QV_STATE_POLL_YIELD;
rc = false;
} else
/* preserve yield marks */
q_vector->state |= IXGBE_QV_STATE_POLL;
spin_unlock_bh(&q_vector->lock);
return rc;
}
/* returns true if someone tried to get the qv while it was locked */
static inline bool ixgbe_qv_unlock_poll(struct ixgbe_q_vector *q_vector)
{
int rc = false;
spin_lock_bh(&q_vector->lock);
WARN_ON(q_vector->state & (IXGBE_QV_STATE_NAPI));
if (q_vector->state & IXGBE_QV_STATE_POLL_YIELD)
rc = true;
q_vector->state = IXGBE_QV_STATE_IDLE;
spin_unlock_bh(&q_vector->lock);
return rc;
}
/* 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));
return q_vector->state & IXGBE_QV_USER_PEND;
}
#else /* CONFIG_NET_LL_RX_POLL */
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)
{
return true;
}
static inline bool ixgbe_qv_unlock_napi(struct ixgbe_q_vector *q_vector)
{
return false;
}
static inline bool ixgbe_qv_lock_poll(struct ixgbe_q_vector *q_vector)
{
return false;
}
static inline bool ixgbe_qv_unlock_poll(struct ixgbe_q_vector *q_vector)
{
return false;
}
static inline bool ixgbe_qv_ll_polling(struct ixgbe_q_vector *q_vector)
{
return false;
}
#endif /* CONFIG_NET_LL_RX_POLL */
#ifdef CONFIG_IXGBE_HWMON
#define IXGBE_HWMON_TYPE_LOC 0
......
......@@ -811,6 +811,7 @@ static int ixgbe_alloc_q_vector(struct ixgbe_adapter *adapter,
/* initialize NAPI */
netif_napi_add(adapter->netdev, &q_vector->napi,
ixgbe_poll, 64);
napi_hash_add(&q_vector->napi);
/* tie q_vector and adapter together */
adapter->q_vector[v_idx] = q_vector;
......@@ -931,6 +932,7 @@ static void ixgbe_free_q_vector(struct ixgbe_adapter *adapter, int v_idx)
adapter->rx_ring[ring->queue_index] = NULL;
adapter->q_vector[v_idx] = NULL;
napi_hash_del(&q_vector->napi);
netif_napi_del(&q_vector->napi);
/*
......
......@@ -1504,7 +1504,9 @@ static void ixgbe_rx_skb(struct ixgbe_q_vector *q_vector,
{
struct ixgbe_adapter *adapter = q_vector->adapter;
if (!(adapter->flags & IXGBE_FLAG_IN_NETPOLL))
if (ixgbe_qv_ll_polling(q_vector))
netif_receive_skb(skb);
else if (!(adapter->flags & IXGBE_FLAG_IN_NETPOLL))
napi_gro_receive(&q_vector->napi, skb);
else
netif_rx(skb);
......@@ -1892,9 +1894,9 @@ dma_sync:
* expensive overhead for IOMMU access this provides a means of avoiding
* it by maintaining the mapping of the page to the syste.
*
* Returns true if all work is completed without reaching budget
* Returns amount of work completed
**/
static bool ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
struct ixgbe_ring *rx_ring,
const int budget)
{
......@@ -1976,6 +1978,7 @@ static bool ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
}
#endif /* IXGBE_FCOE */
skb_mark_ll(skb, &q_vector->napi);
ixgbe_rx_skb(q_vector, skb);
/* update budget accounting */
......@@ -1992,9 +1995,37 @@ static bool ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
if (cleaned_count)
ixgbe_alloc_rx_buffers(rx_ring, cleaned_count);
return (total_rx_packets < budget);
return total_rx_packets;
}
#ifdef CONFIG_NET_LL_RX_POLL
/* must be called with local_bh_disable()d */
static int ixgbe_low_latency_recv(struct napi_struct *napi)
{
struct ixgbe_q_vector *q_vector =
container_of(napi, struct ixgbe_q_vector, napi);
struct ixgbe_adapter *adapter = q_vector->adapter;
struct ixgbe_ring *ring;
int found = 0;
if (test_bit(__IXGBE_DOWN, &adapter->state))
return LL_FLUSH_FAILED;
if (!ixgbe_qv_lock_poll(q_vector))
return LL_FLUSH_BUSY;
ixgbe_for_each_ring(ring, q_vector->rx) {
found = ixgbe_clean_rx_irq(q_vector, ring, 4);
if (found)
break;
}
ixgbe_qv_unlock_poll(q_vector);
return found;
}
#endif /* CONFIG_NET_LL_RX_POLL */
/**
* ixgbe_configure_msix - Configure MSI-X hardware
* @adapter: board private structure
......@@ -2550,6 +2581,9 @@ int ixgbe_poll(struct napi_struct *napi, int budget)
ixgbe_for_each_ring(ring, q_vector->tx)
clean_complete &= !!ixgbe_clean_tx_irq(q_vector, ring);
if (!ixgbe_qv_lock_napi(q_vector))
return budget;
/* attempt to distribute budget to each queue fairly, but don't allow
* the budget to go below 1 because we'll exit polling */
if (q_vector->rx.count > 1)
......@@ -2558,9 +2592,10 @@ int ixgbe_poll(struct napi_struct *napi, int budget)
per_ring_budget = budget;
ixgbe_for_each_ring(ring, q_vector->rx)
clean_complete &= ixgbe_clean_rx_irq(q_vector, ring,
per_ring_budget);
clean_complete &= (ixgbe_clean_rx_irq(q_vector, ring,
per_ring_budget) < per_ring_budget);
ixgbe_qv_unlock_napi(q_vector);
/* If all work not completed, return budget and keep polling */
if (!clean_complete)
return budget;
......@@ -3747,16 +3782,25 @@ static void ixgbe_napi_enable_all(struct ixgbe_adapter *adapter)
{
int q_idx;
for (q_idx = 0; q_idx < adapter->num_q_vectors; q_idx++)
for (q_idx = 0; q_idx < adapter->num_q_vectors; q_idx++) {
ixgbe_qv_init_lock(adapter->q_vector[q_idx]);
napi_enable(&adapter->q_vector[q_idx]->napi);
}
}
static void ixgbe_napi_disable_all(struct ixgbe_adapter *adapter)
{
int q_idx;
for (q_idx = 0; q_idx < adapter->num_q_vectors; 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])) {
pr_info("QV %d locked\n", q_idx);
mdelay(1);
}
}
local_bh_enable();
}
#ifdef CONFIG_IXGBE_DCB
......@@ -7177,6 +7221,9 @@ static const struct net_device_ops ixgbe_netdev_ops = {
#ifdef CONFIG_NET_POLL_CONTROLLER
.ndo_poll_controller = ixgbe_netpoll,
#endif
#ifdef CONFIG_NET_LL_RX_POLL
.ndo_ll_poll = ixgbe_low_latency_recv,
#endif
#ifdef IXGBE_FCOE
.ndo_fcoe_ddp_setup = ixgbe_fcoe_ddp_get,
.ndo_fcoe_ddp_target = ixgbe_fcoe_ddp_target,
......
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