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Message-ID: <1377176182.1703.26.camel@bwh-desktop.uk.level5networks.com>
Date: Thu, 22 Aug 2013 13:56:22 +0100
From: Ben Hutchings <bhutchings@...arflare.com>
To: David Miller <davem@...emloft.net>
CC: <netdev@...r.kernel.org>, <linux-net-drivers@...arflare.com>
Subject: [PATCH net-next 21/32] sfc: Remove efx_process_channel_now()
efx_process_channel_now() is unneeded since self-tests can rely on
normal NAPI polling. Remove it and all calls to it.
efx_channel::work_pending and efx_channel_processed() are also
unneeded (the latter being the same as efx_nic_eventq_read_ack()).
Signed-off-by: Ben Hutchings <bhutchings@...arflare.com>
---
drivers/net/ethernet/sfc/efx.c | 69 ++---------------------------------
drivers/net/ethernet/sfc/efx.h | 2 -
drivers/net/ethernet/sfc/net_driver.h | 2 -
drivers/net/ethernet/sfc/selftest.c | 11 ------
4 files changed, 3 insertions(+), 81 deletions(-)
diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c
index c729688..2b2dba1 100644
--- a/drivers/net/ethernet/sfc/efx.c
+++ b/drivers/net/ethernet/sfc/efx.c
@@ -255,23 +255,6 @@ static int efx_process_channel(struct efx_channel *channel, int budget)
return spent;
}
-/* Mark channel as finished processing
- *
- * Note that since we will not receive further interrupts for this
- * channel before we finish processing and call the eventq_read_ack()
- * method, there is no need to use the interrupt hold-off timers.
- */
-static inline void efx_channel_processed(struct efx_channel *channel)
-{
- /* The interrupt handler for this channel may set work_pending
- * as soon as we acknowledge the events we've seen. Make sure
- * it's cleared before then. */
- channel->work_pending = false;
- smp_wmb();
-
- efx_nic_eventq_read_ack(channel);
-}
-
/* NAPI poll handler
*
* NAPI guarantees serialisation of polls of the same device, which
@@ -316,58 +299,16 @@ static int efx_poll(struct napi_struct *napi, int budget)
/* There is no race here; although napi_disable() will
* only wait for napi_complete(), this isn't a problem
- * since efx_channel_processed() will have no effect if
+ * since efx_nic_eventq_read_ack() will have no effect if
* interrupts have already been disabled.
*/
napi_complete(napi);
- efx_channel_processed(channel);
+ efx_nic_eventq_read_ack(channel);
}
return spent;
}
-/* Process the eventq of the specified channel immediately on this CPU
- *
- * Disable hardware generated interrupts, wait for any existing
- * processing to finish, then directly poll (and ack ) the eventq.
- * Finally reenable NAPI and interrupts.
- *
- * This is for use only during a loopback self-test. It must not
- * deliver any packets up the stack as this can result in deadlock.
- */
-void efx_process_channel_now(struct efx_channel *channel)
-{
- struct efx_nic *efx = channel->efx;
-
- BUG_ON(channel->channel >= efx->n_channels);
- BUG_ON(!channel->enabled);
- BUG_ON(!efx->loopback_selftest);
-
- /* Disable interrupts and wait for ISRs to complete */
- efx_nic_disable_interrupts(efx);
- if (efx->legacy_irq) {
- synchronize_irq(efx->legacy_irq);
- efx->legacy_irq_enabled = false;
- }
- if (channel->irq)
- synchronize_irq(channel->irq);
-
- /* Wait for any NAPI processing to complete */
- napi_disable(&channel->napi_str);
-
- /* Poll the channel */
- efx_process_channel(channel, channel->eventq_mask + 1);
-
- /* Ack the eventq. This may cause an interrupt to be generated
- * when they are reenabled */
- efx_channel_processed(channel);
-
- napi_enable(&channel->napi_str);
- if (efx->legacy_irq)
- efx->legacy_irq_enabled = true;
- efx_nic_enable_interrupts(efx);
-}
-
/* Create event queue
* Event queue memory allocations are done only once. If the channel
* is reset, the memory buffer will be reused; this guards against
@@ -407,11 +348,7 @@ static void efx_start_eventq(struct efx_channel *channel)
netif_dbg(channel->efx, ifup, channel->efx->net_dev,
"chan %d start event queue\n", channel->channel);
- /* The interrupt handler for this channel may set work_pending
- * as soon as we enable it. Make sure it's cleared before
- * then. Similarly, make sure it sees the enabled flag set.
- */
- channel->work_pending = false;
+ /* Make sure the NAPI handler sees the enabled flag set */
channel->enabled = true;
smp_wmb();
diff --git a/drivers/net/ethernet/sfc/efx.h b/drivers/net/ethernet/sfc/efx.h
index bdb30bb..09e633a 100644
--- a/drivers/net/ethernet/sfc/efx.h
+++ b/drivers/net/ethernet/sfc/efx.h
@@ -109,7 +109,6 @@ static inline void efx_filter_rfs_expire(struct efx_channel *channel) {}
/* Channels */
extern int efx_channel_dummy_op_int(struct efx_channel *channel);
extern void efx_channel_dummy_op_void(struct efx_channel *channel);
-extern void efx_process_channel_now(struct efx_channel *channel);
extern int
efx_realloc_channels(struct efx_nic *efx, u32 rxq_entries, u32 txq_entries);
@@ -155,7 +154,6 @@ static inline void efx_schedule_channel(struct efx_channel *channel)
netif_vdbg(channel->efx, intr, channel->efx->net_dev,
"channel %d scheduling NAPI poll on CPU%d\n",
channel->channel, raw_smp_processor_id());
- channel->work_pending = true;
napi_schedule(&channel->napi_str);
}
diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h
index ea64cd8..ad89d7d 100644
--- a/drivers/net/ethernet/sfc/net_driver.h
+++ b/drivers/net/ethernet/sfc/net_driver.h
@@ -361,7 +361,6 @@ enum efx_rx_alloc_method {
* @irq_moderation: IRQ moderation value (in hardware ticks)
* @napi_dev: Net device used with NAPI
* @napi_str: NAPI control structure
- * @work_pending: Is work pending via NAPI?
* @eventq: Event queue buffer
* @eventq_mask: Event queue pointer mask
* @eventq_read_ptr: Event queue read pointer
@@ -393,7 +392,6 @@ struct efx_channel {
unsigned int irq_moderation;
struct net_device *napi_dev;
struct napi_struct napi_str;
- bool work_pending;
struct efx_special_buffer eventq;
unsigned int eventq_mask;
unsigned int eventq_read_ptr;
diff --git a/drivers/net/ethernet/sfc/selftest.c b/drivers/net/ethernet/sfc/selftest.c
index 2069f51..716cff9 100644
--- a/drivers/net/ethernet/sfc/selftest.c
+++ b/drivers/net/ethernet/sfc/selftest.c
@@ -447,14 +447,7 @@ static int efx_begin_loopback(struct efx_tx_queue *tx_queue)
static int efx_poll_loopback(struct efx_nic *efx)
{
struct efx_loopback_state *state = efx->loopback_selftest;
- struct efx_channel *channel;
- /* NAPI polling is not enabled, so process channels
- * synchronously */
- efx_for_each_channel(channel, efx) {
- if (channel->work_pending)
- efx_process_channel_now(channel);
- }
return atomic_read(&state->rx_good) == state->packet_count;
}
@@ -586,10 +579,6 @@ static int efx_wait_for_link(struct efx_nic *efx)
mutex_lock(&efx->mac_lock);
efx->type->monitor(efx);
mutex_unlock(&efx->mac_lock);
- } else {
- struct efx_channel *channel = efx_get_channel(efx, 0);
- if (channel->work_pending)
- efx_process_channel_now(channel);
}
mutex_lock(&efx->mac_lock);
--
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.
--
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