sfc: Split MAC stats DMA initiation and completion

From: Steve Hodgson <shodgson@solarflare.com>

Currently we initiate MAC stats DMA and busy-wait for completion when
stats are requested.  We can improve on this with a periodic timer to
initiate and poll for stats, and opportunistically poll when stats are
requested.

Since efx_nic::stats_disable_count and efx_stats_{disable,enable}()
are Falcon-specific, rename them and move them accordingly.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ben Hutchings 2009-11-25 16:11:35 +00:00 committed by David S. Miller
parent 1dfc5ceacd
commit 55edc6e6ff
9 changed files with 140 additions and 89 deletions

View File

@ -637,6 +637,7 @@ void __efx_reconfigure_port(struct efx_nic *efx)
netif_addr_unlock_bh(efx->net_dev);
}
falcon_stop_nic_stats(efx);
falcon_deconfigure_mac_wrapper(efx);
/* Reconfigure the PHY, disabling transmit in mac level loopback. */
@ -651,6 +652,8 @@ void __efx_reconfigure_port(struct efx_nic *efx)
efx->mac_op->reconfigure(efx);
falcon_start_nic_stats(efx);
/* Inform kernel of loss/gain of carrier */
efx_link_status_changed(efx);
return;
@ -749,7 +752,6 @@ static int efx_init_port(struct efx_nic *efx)
efx->mac_op->reconfigure(efx);
efx->port_initialized = true;
efx_stats_enable(efx);
mutex_unlock(&efx->mac_lock);
return 0;
@ -802,7 +804,6 @@ static void efx_fini_port(struct efx_nic *efx)
if (!efx->port_initialized)
return;
efx_stats_disable(efx);
efx->phy_op->fini(efx);
efx->port_initialized = false;
@ -1158,6 +1159,8 @@ static void efx_start_all(struct efx_nic *efx)
if (efx->state == STATE_RUNNING)
queue_delayed_work(efx->workqueue, &efx->monitor_work,
efx_monitor_interval);
falcon_start_nic_stats(efx);
}
/* Flush all delayed work. Should only be called when no more delayed work
@ -1195,6 +1198,8 @@ static void efx_stop_all(struct efx_nic *efx)
if (!efx->port_enabled)
return;
falcon_stop_nic_stats(efx);
/* Disable interrupts and wait for ISR to complete */
falcon_disable_interrupts(efx);
if (efx->legacy_irq)
@ -1438,20 +1443,6 @@ static int efx_net_stop(struct net_device *net_dev)
return 0;
}
void efx_stats_disable(struct efx_nic *efx)
{
spin_lock(&efx->stats_lock);
++efx->stats_disable_count;
spin_unlock(&efx->stats_lock);
}
void efx_stats_enable(struct efx_nic *efx)
{
spin_lock(&efx->stats_lock);
--efx->stats_disable_count;
spin_unlock(&efx->stats_lock);
}
/* Context: process, dev_base_lock or RTNL held, non-blocking. */
static struct net_device_stats *efx_net_stats(struct net_device *net_dev)
{
@ -1459,17 +1450,9 @@ static struct net_device_stats *efx_net_stats(struct net_device *net_dev)
struct efx_mac_stats *mac_stats = &efx->mac_stats;
struct net_device_stats *stats = &net_dev->stats;
/* Update stats if possible, but do not wait if another thread
* is updating them or if MAC stats fetches are temporarily
* disabled; slightly stale stats are acceptable.
*/
if (!spin_trylock(&efx->stats_lock))
return stats;
if (!efx->stats_disable_count) {
efx->mac_op->update_stats(efx);
falcon_update_nic_stats(efx);
}
spin_unlock(&efx->stats_lock);
spin_lock_bh(&efx->stats_lock);
falcon_update_nic_stats(efx);
spin_unlock_bh(&efx->stats_lock);
stats->rx_packets = mac_stats->rx_packets;
stats->tx_packets = mac_stats->tx_packets;
@ -1726,7 +1709,6 @@ void efx_reset_down(struct efx_nic *efx, enum reset_type method,
{
EFX_ASSERT_RESET_SERIALISED(efx);
efx_stats_disable(efx);
efx_stop_all(efx);
mutex_lock(&efx->mac_lock);
mutex_lock(&efx->spi_lock);
@ -1776,10 +1758,8 @@ int efx_reset_up(struct efx_nic *efx, enum reset_type method,
mutex_unlock(&efx->spi_lock);
mutex_unlock(&efx->mac_lock);
if (ok) {
if (ok)
efx_start_all(efx);
efx_stats_enable(efx);
}
return rc;
}
@ -1977,7 +1957,6 @@ static int efx_init_struct(struct efx_nic *efx, struct efx_nic_type *type,
efx->rx_checksum_enabled = true;
spin_lock_init(&efx->netif_stop_lock);
spin_lock_init(&efx->stats_lock);
efx->stats_disable_count = 1;
mutex_init(&efx->mac_lock);
efx->mac_op = &efx_dummy_mac_operations;
efx->phy_op = &efx_dummy_phy_operations;
@ -2219,9 +2198,8 @@ static int __devinit efx_pci_probe(struct pci_dev *pci_dev,
goto fail4;
}
/* Switch to the running state before we expose the device to
* the OS. This is to ensure that the initial gathering of
* MAC stats succeeds. */
/* Switch to the running state before we expose the device to the OS,
* so that dev_open()|efx_start_all() will actually start the device */
efx->state = STATE_RUNNING;
rc = efx_register_netdev(efx);

View File

@ -60,8 +60,6 @@ extern void efx_process_channel_now(struct efx_channel *channel);
#define EFX_EVQ_MASK (EFX_EVQ_SIZE - 1)
/* Ports */
extern void efx_stats_disable(struct efx_nic *efx);
extern void efx_stats_enable(struct efx_nic *efx);
extern void efx_reconfigure_port(struct efx_nic *efx);
extern void __efx_reconfigure_port(struct efx_nic *efx);

View File

@ -36,8 +36,6 @@
**************************************************************************
*/
static int disable_dma_stats;
/* This is set to 16 for a good reason. In summary, if larger than
* 16, the descriptor cache holds more than a default socket
* buffer's worth of packets (for UDP we can only have at most one
@ -1890,7 +1888,7 @@ static int falcon_reset_macs(struct efx_nic *efx)
/* MAC stats will fail whilst the TX fifo is draining. Serialise
* the drain sequence with the statistics fetch */
efx_stats_disable(efx);
falcon_stop_nic_stats(efx);
efx_reado(efx, &reg, FR_AB_MAC_CTRL);
EFX_SET_OWORD_FIELD(reg, FRF_BB_TXFIFO_DRAIN_EN, 1);
@ -1920,13 +1918,13 @@ static int falcon_reset_macs(struct efx_nic *efx)
udelay(10);
}
efx_stats_enable(efx);
/* If we've reset the EM block and the link is up, then
* we'll have to kick the XAUI link so the PHY can recover */
if (efx->link_state.up && EFX_IS10G(efx) && EFX_WORKAROUND_5147(efx))
falcon_reset_xaui(efx);
falcon_start_nic_stats(efx);
return 0;
}
@ -2010,25 +2008,19 @@ void falcon_reconfigure_mac_wrapper(struct efx_nic *efx)
efx_writeo(efx, &reg, FR_AZ_RX_CFG);
}
int falcon_dma_stats(struct efx_nic *efx, unsigned int done_offset)
static void falcon_stats_request(struct efx_nic *efx)
{
struct falcon_nic_data *nic_data = efx->nic_data;
efx_oword_t reg;
u32 *dma_done;
int i;
if (disable_dma_stats)
return 0;
WARN_ON(nic_data->stats_pending);
WARN_ON(nic_data->stats_disable_count);
/* Statistics fetch will fail if the MAC is in TX drain */
if (falcon_rev(efx) >= FALCON_REV_B0) {
efx_oword_t temp;
efx_reado(efx, &temp, FR_AB_MAC_CTRL);
if (EFX_OWORD_FIELD(temp, FRF_BB_TXFIFO_DRAIN_EN))
return 0;
}
if (nic_data->stats_dma_done == NULL)
return; /* no mac selected */
dma_done = (efx->stats_buffer.addr + done_offset);
*dma_done = FALCON_STATS_NOT_DONE;
*nic_data->stats_dma_done = FALCON_STATS_NOT_DONE;
nic_data->stats_pending = true;
wmb(); /* ensure done flag is clear */
/* Initiate DMA transfer of stats */
@ -2038,17 +2030,37 @@ int falcon_dma_stats(struct efx_nic *efx, unsigned int done_offset)
efx->stats_buffer.dma_addr);
efx_writeo(efx, &reg, FR_AB_MAC_STAT_DMA);
/* Wait for transfer to complete */
for (i = 0; i < 400; i++) {
if (*(volatile u32 *)dma_done == FALCON_STATS_DONE) {
rmb(); /* Ensure the stats are valid. */
return 0;
}
udelay(10);
}
mod_timer(&nic_data->stats_timer, round_jiffies_up(jiffies + HZ / 2));
}
EFX_ERR(efx, "timed out waiting for statistics\n");
return -ETIMEDOUT;
static void falcon_stats_complete(struct efx_nic *efx)
{
struct falcon_nic_data *nic_data = efx->nic_data;
if (!nic_data->stats_pending)
return;
nic_data->stats_pending = 0;
if (*nic_data->stats_dma_done == FALCON_STATS_DONE) {
rmb(); /* read the done flag before the stats */
efx->mac_op->update_stats(efx);
} else {
EFX_ERR(efx, "timed out waiting for statistics\n");
}
}
static void falcon_stats_timer_func(unsigned long context)
{
struct efx_nic *efx = (struct efx_nic *)context;
struct falcon_nic_data *nic_data = efx->nic_data;
spin_lock(&efx->stats_lock);
falcon_stats_complete(efx);
if (nic_data->stats_disable_count == 0)
falcon_stats_request(efx);
spin_unlock(&efx->stats_lock);
}
/**************************************************************************
@ -2206,10 +2218,12 @@ static void falcon_clock_mac(struct efx_nic *efx)
int falcon_switch_mac(struct efx_nic *efx)
{
struct efx_mac_operations *old_mac_op = efx->mac_op;
struct falcon_nic_data *nic_data = efx->nic_data;
unsigned int stats_done_offset;
int rc = 0;
/* Don't try to fetch MAC stats while we're switching MACs */
efx_stats_disable(efx);
falcon_stop_nic_stats(efx);
/* Internal loopbacks override the phy speed setting */
if (efx->loopback_mode == LOOPBACK_GMAC) {
@ -2224,6 +2238,12 @@ int falcon_switch_mac(struct efx_nic *efx)
efx->mac_op = (EFX_IS10G(efx) ?
&falcon_xmac_operations : &falcon_gmac_operations);
if (EFX_IS10G(efx))
stats_done_offset = XgDmaDone_offset;
else
stats_done_offset = GDmaDone_offset;
nic_data->stats_dma_done = efx->stats_buffer.addr + stats_done_offset;
if (old_mac_op == efx->mac_op)
goto out;
@ -2235,7 +2255,7 @@ int falcon_switch_mac(struct efx_nic *efx)
rc = falcon_reset_macs(efx);
out:
efx_stats_enable(efx);
falcon_start_nic_stats(efx);
return rc;
}
@ -2900,6 +2920,10 @@ int falcon_probe_nic(struct efx_nic *efx)
goto fail6;
}
nic_data->stats_disable_count = 1;
setup_timer(&nic_data->stats_timer, &falcon_stats_timer_func,
(unsigned long)efx);
return 0;
fail6:
@ -3125,11 +3149,58 @@ void falcon_remove_nic(struct efx_nic *efx)
void falcon_update_nic_stats(struct efx_nic *efx)
{
struct falcon_nic_data *nic_data = efx->nic_data;
efx_oword_t cnt;
if (nic_data->stats_disable_count)
return;
efx_reado(efx, &cnt, FR_AZ_RX_NODESC_DROP);
efx->n_rx_nodesc_drop_cnt +=
EFX_OWORD_FIELD(cnt, FRF_AB_RX_NODESC_DROP_CNT);
if (nic_data->stats_pending &&
*nic_data->stats_dma_done == FALCON_STATS_DONE) {
nic_data->stats_pending = false;
rmb(); /* read the done flag before the stats */
efx->mac_op->update_stats(efx);
}
}
void falcon_start_nic_stats(struct efx_nic *efx)
{
struct falcon_nic_data *nic_data = efx->nic_data;
spin_lock_bh(&efx->stats_lock);
if (--nic_data->stats_disable_count == 0)
falcon_stats_request(efx);
spin_unlock_bh(&efx->stats_lock);
}
void falcon_stop_nic_stats(struct efx_nic *efx)
{
struct falcon_nic_data *nic_data = efx->nic_data;
int i;
might_sleep();
spin_lock_bh(&efx->stats_lock);
++nic_data->stats_disable_count;
spin_unlock_bh(&efx->stats_lock);
del_timer_sync(&nic_data->stats_timer);
/* Wait enough time for the most recent transfer to
* complete. */
for (i = 0; i < 4 && nic_data->stats_pending; i++) {
if (*nic_data->stats_dma_done == FALCON_STATS_DONE)
break;
msleep(1);
}
spin_lock_bh(&efx->stats_lock);
falcon_stats_complete(efx);
spin_unlock_bh(&efx->stats_lock);
}
/**************************************************************************

View File

@ -75,10 +75,18 @@ struct falcon_board {
* struct falcon_nic_data - Falcon NIC state
* @pci_dev2: Secondary function of Falcon A
* @board: Board state and functions
* @stats_disable_count: Nest count for disabling statistics fetches
* @stats_pending: Is there a pending DMA of MAC statistics.
* @stats_timer: A timer for regularly fetching MAC statistics.
* @stats_dma_done: Pointer to the flag which indicates DMA completion.
*/
struct falcon_nic_data {
struct pci_dev *pci_dev2;
struct falcon_board board;
unsigned int stats_disable_count;
bool stats_pending;
struct timer_list stats_timer;
u32 *stats_dma_done;
};
static inline struct falcon_board *falcon_board(struct efx_nic *efx)
@ -128,8 +136,6 @@ extern void falcon_remove_port(struct efx_nic *efx);
/* MAC/PHY */
extern int falcon_switch_mac(struct efx_nic *efx);
extern bool falcon_xaui_link_ok(struct efx_nic *efx);
extern int falcon_dma_stats(struct efx_nic *efx,
unsigned int done_offset);
extern void falcon_drain_tx_fifo(struct efx_nic *efx);
extern void falcon_deconfigure_mac_wrapper(struct efx_nic *efx);
extern void falcon_reconfigure_mac_wrapper(struct efx_nic *efx);
@ -154,6 +160,8 @@ extern int falcon_flush_queues(struct efx_nic *efx);
extern int falcon_reset_hw(struct efx_nic *efx, enum reset_type method);
extern void falcon_remove_nic(struct efx_nic *efx);
extern void falcon_update_nic_stats(struct efx_nic *efx);
extern void falcon_start_nic_stats(struct efx_nic *efx);
extern void falcon_stop_nic_stats(struct efx_nic *efx);
extern void falcon_set_multicast_hash(struct efx_nic *efx);
extern int falcon_reset_xaui(struct efx_nic *efx);

View File

@ -347,14 +347,14 @@ static ssize_t set_phy_flash_cfg(struct device *dev,
* MAC stats accordingly. */
efx->phy_mode = new_mode;
if (new_mode & PHY_MODE_SPECIAL)
efx_stats_disable(efx);
falcon_stop_nic_stats(efx);
if (falcon_board(efx)->type->id == FALCON_BOARD_SFE4001)
err = sfe4001_poweron(efx);
else
err = sfn4111t_reset(efx);
efx_reconfigure_port(efx);
if (!(new_mode & PHY_MODE_SPECIAL))
efx_stats_enable(efx);
falcon_start_nic_stats(efx);
}
rtnl_unlock();
@ -441,7 +441,7 @@ static int sfe4001_init(struct efx_nic *efx)
if (efx->phy_mode & PHY_MODE_SPECIAL) {
/* PHY won't generate a 156.25 MHz clock and MAC stats fetch
* will fail. */
efx_stats_disable(efx);
falcon_stop_nic_stats(efx);
}
rc = sfe4001_poweron(efx);
if (rc)
@ -504,7 +504,7 @@ static void sfn4111t_init_phy(struct efx_nic *efx)
return;
efx->phy_mode = PHY_MODE_SPECIAL;
efx_stats_disable(efx);
falcon_stop_nic_stats(efx);
}
sfn4111t_reset(efx);
@ -531,7 +531,7 @@ static int sfn4111t_init(struct efx_nic *efx)
if (efx->phy_mode & PHY_MODE_SPECIAL)
/* PHY may not generate a 156.25 MHz clock and MAC
* stats fetch will fail. */
efx_stats_disable(efx);
falcon_stop_nic_stats(efx);
return 0;

View File

@ -130,11 +130,6 @@ static void falcon_update_stats_gmac(struct efx_nic *efx)
struct efx_mac_stats *mac_stats = &efx->mac_stats;
unsigned long old_rx_pause, old_tx_pause;
unsigned long new_rx_pause, new_tx_pause;
int rc;
rc = falcon_dma_stats(efx, GDmaDone_offset);
if (rc)
return;
/* Pause frames are erroneously counted as errors (SFC bug 3269) */
old_rx_pause = mac_stats->rx_pause;

View File

@ -60,9 +60,13 @@ static void falcon_setup_xaui(struct efx_nic *efx)
int falcon_reset_xaui(struct efx_nic *efx)
{
struct falcon_nic_data *nic_data = efx->nic_data;
efx_oword_t reg;
int count;
/* Don't fetch MAC statistics over an XMAC reset */
WARN_ON(nic_data->stats_disable_count == 0);
/* Start reset sequence */
EFX_POPULATE_OWORD_1(reg, FRF_AB_XX_RST_XX_EN, 1);
efx_writeo(efx, &reg, FR_AB_XX_PWR_RST);
@ -250,6 +254,8 @@ static void falcon_check_xaui_link_up(struct efx_nic *efx, int tries)
/* XAUI link is expected to be down */
return;
falcon_stop_nic_stats(efx);
while (!efx->mac_up && tries) {
EFX_LOG(efx, "bashing xaui\n");
falcon_reset_xaui(efx);
@ -258,6 +264,8 @@ static void falcon_check_xaui_link_up(struct efx_nic *efx, int tries)
efx->mac_up = falcon_xaui_link_ok(efx);
--tries;
}
falcon_start_nic_stats(efx);
}
static void falcon_reconfigure_xmac(struct efx_nic *efx)
@ -276,11 +284,6 @@ static void falcon_reconfigure_xmac(struct efx_nic *efx)
static void falcon_update_stats_xmac(struct efx_nic *efx)
{
struct efx_mac_stats *mac_stats = &efx->mac_stats;
int rc;
rc = falcon_dma_stats(efx, XgDmaDone_offset);
if (rc)
return;
/* Update MAC stats from DMAed values */
FALCON_STAT(efx, XgRxOctets, rx_bytes);

View File

@ -717,7 +717,6 @@ union efx_multicast_hash {
* &struct net_device_stats.
* @stats_buffer: DMA buffer for statistics
* @stats_lock: Statistics update lock. Serialises statistics fetches
* @stats_disable_count: Nest count for disabling statistics fetches
* @mac_op: MAC interface
* @mac_address: Permanent MAC address
* @phy_type: PHY type
@ -799,7 +798,6 @@ struct efx_nic {
struct efx_mac_stats mac_stats;
struct efx_buffer stats_buffer;
spinlock_t stats_lock;
unsigned int stats_disable_count;
struct efx_mac_operations *mac_op;
unsigned char mac_address[ETH_ALEN];

View File

@ -374,7 +374,7 @@ static int tenxpress_special_reset(struct efx_nic *efx)
/* The XGMAC clock is driven from the SFC7101/SFT9001 312MHz clock, so
* a special software reset can glitch the XGMAC sufficiently for stats
* requests to fail. */
efx_stats_disable(efx);
falcon_stop_nic_stats(efx);
/* Initiate reset */
reg = efx_mdio_read(efx, MDIO_MMD_PMAPMD, PMA_PMD_XCONTROL_REG);
@ -396,7 +396,7 @@ static int tenxpress_special_reset(struct efx_nic *efx)
/* Wait for the XGXS state machine to churn */
mdelay(10);
out:
efx_stats_enable(efx);
falcon_start_nic_stats(efx);
return rc;
}