From 1646a6f352a6f70fcca828589ed04797aa09d494 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Thu, 5 Jan 2012 20:14:10 +0000 Subject: [PATCH] sfc: Clean up test interrupt handling Interrupts are normally generated by the event queues, moderated by timers. However, they may also be triggered by detection of a 'fatal' error condition (e.g. memory parity error) or by the host writing to certain CSR fields as part of a self-test. The IRQ level/index used for these on Falcon rev B0 and Siena is set by the KER_INT_LEVE_SEL field and cached by the driver in efx_nic::fatal_irq_level. Since this value is also relevant to self-tests rename the field to just 'irq_level'. Avoid unnecessary cache traffic by using a per-channel 'last_irq_cpu' field and only writing to the per-controller field when the interrupt matches efx_nic::irq_level. Remove the volatile qualifier and use ACCESS_ONCE in the places we read these fields. Signed-off-by: Ben Hutchings --- drivers/net/ethernet/sfc/efx.h | 6 ++++++ drivers/net/ethernet/sfc/falcon.c | 4 ++-- drivers/net/ethernet/sfc/net_driver.h | 15 ++++++++------- drivers/net/ethernet/sfc/nic.c | 27 +++++++++++++-------------- drivers/net/ethernet/sfc/selftest.c | 12 +++++++----- 5 files changed, 36 insertions(+), 28 deletions(-) diff --git a/drivers/net/ethernet/sfc/efx.h b/drivers/net/ethernet/sfc/efx.h index a3541ac6ea01..e0b66d158d79 100644 --- a/drivers/net/ethernet/sfc/efx.h +++ b/drivers/net/ethernet/sfc/efx.h @@ -145,6 +145,12 @@ static inline void efx_schedule_channel(struct efx_channel *channel) napi_schedule(&channel->napi_str); } +static inline void efx_schedule_channel_irq(struct efx_channel *channel) +{ + channel->last_irq_cpu = raw_smp_processor_id(); + efx_schedule_channel(channel); +} + extern void efx_link_status_changed(struct efx_nic *efx); extern void efx_link_set_advertising(struct efx_nic *efx, u32); extern void efx_link_set_wanted_fc(struct efx_nic *efx, u8); diff --git a/drivers/net/ethernet/sfc/falcon.c b/drivers/net/ethernet/sfc/falcon.c index b4e91edec0fa..98285115df10 100644 --- a/drivers/net/ethernet/sfc/falcon.c +++ b/drivers/net/ethernet/sfc/falcon.c @@ -189,9 +189,9 @@ irqreturn_t falcon_legacy_interrupt_a1(int irq, void *dev_id) falcon_irq_ack_a1(efx); if (queues & 1) - efx_schedule_channel(efx_get_channel(efx, 0)); + efx_schedule_channel_irq(efx_get_channel(efx, 0)); if (queues & 2) - efx_schedule_channel(efx_get_channel(efx, 1)); + efx_schedule_channel_irq(efx_get_channel(efx, 1)); return IRQ_HANDLED; } /************************************************************************** diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h index 8ce4d068bba5..a4cf8cb8180c 100644 --- a/drivers/net/ethernet/sfc/net_driver.h +++ b/drivers/net/ethernet/sfc/net_driver.h @@ -325,6 +325,7 @@ enum efx_rx_alloc_method { * @eventq_mask: Event queue pointer mask * @eventq_read_ptr: Event queue read pointer * @last_eventq_read_ptr: Last event queue read pointer value. + * @last_irq_cpu: Last CPU to handle interrupt for this channel * @irq_count: Number of IRQs since last adaptive moderation decision * @irq_mod_score: IRQ moderation score * @rx_alloc_level: Watermark based heuristic counter for pushing descriptors @@ -355,6 +356,7 @@ struct efx_channel { unsigned int eventq_read_ptr; unsigned int last_eventq_read_ptr; + int last_irq_cpu; unsigned int irq_count; unsigned int irq_mod_score; #ifdef CONFIG_RFS_ACCEL @@ -648,7 +650,7 @@ struct efx_filter_state; * @int_error_expire: Time at which error count will be expired * @irq_status: Interrupt status buffer * @irq_zero_count: Number of legacy IRQs seen with queue flags == 0 - * @fatal_irq_level: IRQ level (bit number) used for serious errors + * @irq_level: IRQ level/index for IRQs not triggered by an event queue * @mtd_list: List of MTDs attached to the NIC * @nic_data: Hardware dependent state * @mac_lock: MAC access lock. Protects @port_enabled, @phy_mode, @@ -679,10 +681,9 @@ struct efx_filter_state; * @loopback_selftest: Offline self-test private state * @monitor_work: Hardware monitor workitem * @biu_lock: BIU (bus interface unit) lock - * @last_irq_cpu: Last CPU to handle interrupt. - * This register is written with the SMP processor ID whenever an - * interrupt is handled. It is used by efx_nic_test_interrupt() - * to verify that an interrupt has occurred. + * @last_irq_cpu: Last CPU to handle a possible test interrupt. This + * field is used by efx_test_interrupts() to verify that an + * interrupt has occurred. * @n_rx_nodesc_drop_cnt: RX no descriptor drop count * @mac_stats: MAC statistics. These include all statistics the MACs * can provide. Generic code converts these into a standard @@ -735,7 +736,7 @@ struct efx_nic { struct efx_buffer irq_status; unsigned irq_zero_count; - unsigned fatal_irq_level; + unsigned irq_level; #ifdef CONFIG_SFC_MTD struct list_head mtd_list; @@ -779,7 +780,7 @@ struct efx_nic { struct delayed_work monitor_work ____cacheline_aligned_in_smp; spinlock_t biu_lock; - volatile signed int last_irq_cpu; + int last_irq_cpu; unsigned n_rx_nodesc_drop_cnt; struct efx_mac_stats mac_stats; spinlock_t stats_lock; diff --git a/drivers/net/ethernet/sfc/nic.c b/drivers/net/ethernet/sfc/nic.c index bf07bd0488cf..de7aa1c8ebda 100644 --- a/drivers/net/ethernet/sfc/nic.c +++ b/drivers/net/ethernet/sfc/nic.c @@ -1311,7 +1311,7 @@ static inline void efx_nic_interrupts(struct efx_nic *efx, efx_oword_t int_en_reg_ker; EFX_POPULATE_OWORD_3(int_en_reg_ker, - FRF_AZ_KER_INT_LEVE_SEL, efx->fatal_irq_level, + FRF_AZ_KER_INT_LEVE_SEL, efx->irq_level, FRF_AZ_KER_INT_KER, force, FRF_AZ_DRV_INT_EN_KER, enabled); efx_writeo(efx, &int_en_reg_ker, FR_AZ_INT_EN_KER); @@ -1427,11 +1427,12 @@ static irqreturn_t efx_legacy_interrupt(int irq, void *dev_id) efx_readd(efx, ®, FR_BZ_INT_ISR0); queues = EFX_EXTRACT_DWORD(reg, 0, 31); - /* Check to see if we have a serious error condition */ - if (queues & (1U << efx->fatal_irq_level)) { + /* Handle non-event-queue sources */ + if (queues & (1U << efx->irq_level)) { syserr = EFX_OWORD_FIELD(*int_ker, FSF_AZ_NET_IVEC_FATAL_INT); if (unlikely(syserr)) return efx_nic_fatal_interrupt(efx); + efx->last_irq_cpu = raw_smp_processor_id(); } if (queues != 0) { @@ -1441,7 +1442,7 @@ static irqreturn_t efx_legacy_interrupt(int irq, void *dev_id) /* Schedule processing of any interrupting queues */ efx_for_each_channel(channel, efx) { if (queues & 1) - efx_schedule_channel(channel); + efx_schedule_channel_irq(channel); queues >>= 1; } result = IRQ_HANDLED; @@ -1458,18 +1459,16 @@ static irqreturn_t efx_legacy_interrupt(int irq, void *dev_id) efx_for_each_channel(channel, efx) { event = efx_event(channel, channel->eventq_read_ptr); if (efx_event_present(event)) - efx_schedule_channel(channel); + efx_schedule_channel_irq(channel); else efx_nic_eventq_read_ack(channel); } } - if (result == IRQ_HANDLED) { - efx->last_irq_cpu = raw_smp_processor_id(); + if (result == IRQ_HANDLED) netif_vdbg(efx, intr, efx->net_dev, "IRQ %d on CPU %d status " EFX_DWORD_FMT "\n", irq, raw_smp_processor_id(), EFX_DWORD_VAL(reg)); - } return result; } @@ -1488,20 +1487,20 @@ static irqreturn_t efx_msi_interrupt(int irq, void *dev_id) efx_oword_t *int_ker = efx->irq_status.addr; int syserr; - efx->last_irq_cpu = raw_smp_processor_id(); netif_vdbg(efx, intr, efx->net_dev, "IRQ %d on CPU %d status " EFX_OWORD_FMT "\n", irq, raw_smp_processor_id(), EFX_OWORD_VAL(*int_ker)); - /* Check to see if we have a serious error condition */ - if (channel->channel == efx->fatal_irq_level) { + /* Handle non-event-queue sources */ + if (channel->channel == efx->irq_level) { syserr = EFX_OWORD_FIELD(*int_ker, FSF_AZ_NET_IVEC_FATAL_INT); if (unlikely(syserr)) return efx_nic_fatal_interrupt(efx); + efx->last_irq_cpu = raw_smp_processor_id(); } /* Schedule processing of the channel */ - efx_schedule_channel(channel); + efx_schedule_channel_irq(channel); return IRQ_HANDLED; } @@ -1640,10 +1639,10 @@ void efx_nic_init_common(struct efx_nic *efx) if (EFX_WORKAROUND_17213(efx) && !EFX_INT_MODE_USE_MSI(efx)) /* Use an interrupt level unused by event queues */ - efx->fatal_irq_level = 0x1f; + efx->irq_level = 0x1f; else /* Use a valid MSI-X vector */ - efx->fatal_irq_level = 0; + efx->irq_level = 0; /* Enable all the genuinely fatal interrupts. (They are still * masked by the overall interrupt mask, controlled by diff --git a/drivers/net/ethernet/sfc/selftest.c b/drivers/net/ethernet/sfc/selftest.c index 0f8478924475..7def480570c3 100644 --- a/drivers/net/ethernet/sfc/selftest.c +++ b/drivers/net/ethernet/sfc/selftest.c @@ -130,6 +130,8 @@ static int efx_test_chip(struct efx_nic *efx, struct efx_self_tests *tests) static int efx_test_interrupts(struct efx_nic *efx, struct efx_self_tests *tests) { + int cpu; + netif_dbg(efx, drv, efx->net_dev, "testing interrupts\n"); tests->interrupt = -1; @@ -142,7 +144,8 @@ static int efx_test_interrupts(struct efx_nic *efx, /* Wait for arrival of test interrupt. */ netif_dbg(efx, drv, efx->net_dev, "waiting for test interrupt\n"); schedule_timeout_uninterruptible(HZ / 10); - if (efx->last_irq_cpu >= 0) + cpu = ACCESS_ONCE(efx->last_irq_cpu); + if (cpu >= 0) goto success; netif_err(efx, drv, efx->net_dev, "timed out waiting for interrupt\n"); @@ -150,8 +153,7 @@ static int efx_test_interrupts(struct efx_nic *efx, success: netif_dbg(efx, drv, efx->net_dev, "%s test interrupt seen on CPU%d\n", - INT_MODE(efx), - efx->last_irq_cpu); + INT_MODE(efx), cpu); tests->interrupt = 1; return 0; } @@ -165,7 +167,7 @@ static int efx_test_eventq_irq(struct efx_channel *channel, bool napi_ran, dma_seen, int_seen; read_ptr = channel->eventq_read_ptr; - channel->efx->last_irq_cpu = -1; + channel->last_irq_cpu = -1; smp_wmb(); efx_nic_generate_test_event(channel); @@ -182,7 +184,7 @@ static int efx_test_eventq_irq(struct efx_channel *channel, } else { napi_ran = false; dma_seen = efx_nic_event_present(channel); - int_seen = efx->last_irq_cpu >= 0; + int_seen = ACCESS_ONCE(channel->last_irq_cpu) >= 0; } napi_enable(&channel->napi_str); efx_nic_eventq_read_ack(channel); -- 2.20.1