diff --git a/drivers/staging/octeon/ethernet-defines.h b/drivers/staging/octeon/ethernet-defines.h index 6b8065f594bf..9c4910e45d28 100644 --- a/drivers/staging/octeon/ethernet-defines.h +++ b/drivers/staging/octeon/ethernet-defines.h @@ -45,10 +45,6 @@ * Controls if the Octeon TCP/UDP checksum engine is used for packet * output. If this is zero, the kernel will perform the checksum in * software. - * USE_MULTICORE_RECEIVE - * Process receive interrupts on multiple cores. This spreads the network - * load across the first 8 processors. If ths is zero, only one core - * processes incomming packets. * USE_ASYNC_IOBDMA * Use asynchronous IO access to hardware. This uses Octeon's asynchronous * IOBDMAs to issue IO accesses without stalling. Set this to zero @@ -79,15 +75,8 @@ #define REUSE_SKBUFFS_WITHOUT_FREE 1 #endif -/* Max interrupts per second per core */ -#define INTERRUPT_LIMIT 10000 - -/* Don't limit the number of interrupts */ -/*#define INTERRUPT_LIMIT 0 */ #define USE_HW_TCPUDP_CHECKSUM 1 -#define USE_MULTICORE_RECEIVE 1 - /* Enable Random Early Dropping under load */ #define USE_RED 1 #define USE_ASYNC_IOBDMA (CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE > 0) @@ -105,17 +94,10 @@ /* Use this to not have FPA frees control L2 */ /*#define DONT_WRITEBACK(x) 0 */ -/* Maximum number of packets to process per interrupt. */ -#define MAX_RX_PACKETS 120 /* Maximum number of SKBs to try to free per xmit packet. */ #define MAX_SKB_TO_FREE 10 #define MAX_OUT_QUEUE_DEPTH 1000 -#ifndef CONFIG_SMP -#undef USE_MULTICORE_RECEIVE -#define USE_MULTICORE_RECEIVE 0 -#endif - #define IP_PROTOCOL_TCP 6 #define IP_PROTOCOL_UDP 0x11 diff --git a/drivers/staging/octeon/ethernet-rx.c b/drivers/staging/octeon/ethernet-rx.c index f63459a96dad..b2e6ab6a3349 100644 --- a/drivers/staging/octeon/ethernet-rx.c +++ b/drivers/staging/octeon/ethernet-rx.c @@ -4,7 +4,7 @@ * Contact: support@caviumnetworks.com * This file is part of the OCTEON SDK * - * Copyright (c) 2003-2007 Cavium Networks + * Copyright (c) 2003-2010 Cavium Networks * * This file is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License, Version 2, as @@ -27,12 +27,14 @@ #include #include #include +#include #include #include #include #include #include #include +#include #include #ifdef CONFIG_XFRM #include @@ -44,8 +46,9 @@ #include #include "ethernet-defines.h" -#include "octeon-ethernet.h" #include "ethernet-mem.h" +#include "ethernet-rx.h" +#include "octeon-ethernet.h" #include "ethernet-util.h" #include "cvmx-helper.h" @@ -57,57 +60,83 @@ #include "cvmx-gmxx-defs.h" -struct cvm_tasklet_wrapper { - struct tasklet_struct t; -}; +struct cvm_napi_wrapper { + struct napi_struct napi; +} ____cacheline_aligned_in_smp; -/* - * Aligning the tasklet_struct on cachline boundries seems to decrease - * throughput even though in theory it would reduce contantion on the - * cache lines containing the locks. - */ +static struct cvm_napi_wrapper cvm_oct_napi[NR_CPUS] __cacheline_aligned_in_smp; -static struct cvm_tasklet_wrapper cvm_oct_tasklet[NR_CPUS]; +struct cvm_oct_core_state { + int baseline_cores; + /* + * The number of additional cores that could be processing + * input packtes. + */ + atomic_t available_cores; + cpumask_t cpu_state; +} ____cacheline_aligned_in_smp; + +static struct cvm_oct_core_state core_state __cacheline_aligned_in_smp; + +static void cvm_oct_enable_napi(void *_) +{ + int cpu = smp_processor_id(); + napi_schedule(&cvm_oct_napi[cpu].napi); +} + +static void cvm_oct_enable_one_cpu(void) +{ + int v; + int cpu; + + /* Check to see if more CPUs are available for receive processing... */ + v = atomic_sub_if_positive(1, &core_state.available_cores); + if (v < 0) + return; + + /* ... if a CPU is available, Turn on NAPI polling for that CPU. */ + for_each_online_cpu(cpu) { + if (!cpu_test_and_set(cpu, core_state.cpu_state)) { + v = smp_call_function_single(cpu, cvm_oct_enable_napi, + NULL, 0); + if (v) + panic("Can't enable NAPI."); + break; + } + } +} + +static void cvm_oct_no_more_work(void) +{ + int cpu = smp_processor_id(); + + /* + * CPU zero is special. It always has the irq enabled when + * waiting for incoming packets. + */ + if (cpu == 0) { + enable_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group); + return; + } + + cpu_clear(cpu, core_state.cpu_state); + atomic_add(1, &core_state.available_cores); +} /** * Interrupt handler. The interrupt occurs whenever the POW - * transitions from 0->1 packets in our group. + * has packets in our group. * - * @cpl: - * @dev_id: - * @regs: - * Returns */ -irqreturn_t cvm_oct_do_interrupt(int cpl, void *dev_id) +static irqreturn_t cvm_oct_do_interrupt(int cpl, void *dev_id) { - /* Acknowledge the interrupt */ - if (INTERRUPT_LIMIT) - cvmx_write_csr(CVMX_POW_WQ_INT, 1 << pow_receive_group); - else - cvmx_write_csr(CVMX_POW_WQ_INT, 0x10001 << pow_receive_group); - preempt_disable(); - tasklet_schedule(&cvm_oct_tasklet[smp_processor_id()].t); - preempt_enable(); + /* Disable the IRQ and start napi_poll. */ + disable_irq_nosync(OCTEON_IRQ_WORKQ0 + pow_receive_group); + cvm_oct_enable_napi(NULL); + return IRQ_HANDLED; } -#ifdef CONFIG_NET_POLL_CONTROLLER -/** - * This is called when the kernel needs to manually poll the - * device. For Octeon, this is simply calling the interrupt - * handler. We actually poll all the devices, not just the - * one supplied. - * - * @dev: Device to poll. Unused - */ -void cvm_oct_poll_controller(struct net_device *dev) -{ - preempt_disable(); - tasklet_schedule(&cvm_oct_tasklet[smp_processor_id()].t); - preempt_enable(); -} -#endif - /** * This is called on receive errors, and determines if the packet * can be dropped early-on in cvm_oct_tasklet_rx(). @@ -195,19 +224,19 @@ static inline int cvm_oct_check_rcv_error(cvmx_wqe_t *work) } /** - * Tasklet function that is scheduled on a core when an interrupt occurs. + * The NAPI poll function. * - * @unused: + * @napi: The NAPI instance, or null if called from cvm_oct_poll_controller + * @budget: Maximum number of packets to receive. */ -void cvm_oct_tasklet_rx(unsigned long unused) +static int cvm_oct_napi_poll(struct napi_struct *napi, int budget) { - const int coreid = cvmx_get_core_num(); - uint64_t old_group_mask; - uint64_t old_scratch; - int rx_count = 0; - int number_to_free; - int num_freed; - int packet_not_copied; + const int coreid = cvmx_get_core_num(); + uint64_t old_group_mask; + uint64_t old_scratch; + int rx_count = 0; + int did_work_request = 0; + int packet_not_copied; /* Prefetch cvm_oct_device since we know we need it soon */ prefetch(cvm_oct_device); @@ -223,59 +252,63 @@ void cvm_oct_tasklet_rx(unsigned long unused) cvmx_write_csr(CVMX_POW_PP_GRP_MSKX(coreid), (old_group_mask & ~0xFFFFull) | 1 << pow_receive_group); - if (USE_ASYNC_IOBDMA) + if (USE_ASYNC_IOBDMA) { cvmx_pow_work_request_async(CVMX_SCR_SCRATCH, CVMX_POW_NO_WAIT); + did_work_request = 1; + } - while (1) { + while (rx_count < budget) { struct sk_buff *skb = NULL; + struct sk_buff **pskb = NULL; int skb_in_hw; cvmx_wqe_t *work; - if (USE_ASYNC_IOBDMA) { + if (USE_ASYNC_IOBDMA && did_work_request) work = cvmx_pow_work_response_async(CVMX_SCR_SCRATCH); - } else { - if ((INTERRUPT_LIMIT == 0) - || likely(rx_count < MAX_RX_PACKETS)) - work = - cvmx_pow_work_request_sync - (CVMX_POW_NO_WAIT); - else - work = NULL; - } + else + work = cvmx_pow_work_request_sync(CVMX_POW_NO_WAIT); + prefetch(work); - if (work == NULL) + did_work_request = 0; + if (work == NULL) { + union cvmx_pow_wq_int wq_int; + wq_int.u64 = 0; + wq_int.s.iq_dis = 1 << pow_receive_group; + wq_int.s.wq_int = 1 << pow_receive_group; + cvmx_write_csr(CVMX_POW_WQ_INT, wq_int.u64); break; + } + pskb = (struct sk_buff **)(cvm_oct_get_buffer_ptr(work->packet_ptr) - sizeof(void *)); + prefetch(pskb); - /* - * Limit each core to processing MAX_RX_PACKETS - * packets without a break. This way the RX can't - * starve the TX task. - */ - if (USE_ASYNC_IOBDMA) { + if (USE_ASYNC_IOBDMA && rx_count < (budget - 1)) { + cvmx_pow_work_request_async_nocheck(CVMX_SCR_SCRATCH, CVMX_POW_NO_WAIT); + did_work_request = 1; + } - if ((INTERRUPT_LIMIT == 0) - || likely(rx_count < MAX_RX_PACKETS)) - cvmx_pow_work_request_async_nocheck - (CVMX_SCR_SCRATCH, CVMX_POW_NO_WAIT); - else { - cvmx_scratch_write64(CVMX_SCR_SCRATCH, - 0x8000000000000000ull); - cvmx_pow_tag_sw_null_nocheck(); - } + if (rx_count == 0) { + /* + * First time through, see if there is enough + * work waiting to merit waking another + * CPU. + */ + union cvmx_pow_wq_int_cntx counts; + int backlog; + int cores_in_use = core_state.baseline_cores - atomic_read(&core_state.available_cores); + counts.u64 = cvmx_read_csr(CVMX_POW_WQ_INT_CNTX(pow_receive_group)); + backlog = counts.s.iq_cnt + counts.s.ds_cnt; + if (backlog > budget * cores_in_use && napi != NULL) + cvm_oct_enable_one_cpu(); } skb_in_hw = USE_SKBUFFS_IN_HW && work->word2.s.bufs == 1; if (likely(skb_in_hw)) { - skb = - *(struct sk_buff - **)(cvm_oct_get_buffer_ptr(work->packet_ptr) - - sizeof(void *)); + skb = *pskb; prefetch(&skb->head); prefetch(&skb->len); } prefetch(cvm_oct_device[work->ipprt]); - rx_count++; /* Immediately throw away all packets with receive errors */ if (unlikely(work->word2.snoip.rcv_error)) { if (cvm_oct_check_rcv_error(work)) @@ -391,6 +424,7 @@ void cvm_oct_tasklet_rx(unsigned long unused) #endif } netif_receive_skb(skb); + rx_count++; } else { /* Drop any packet received for a device that isn't up */ /* @@ -432,47 +466,93 @@ void cvm_oct_tasklet_rx(unsigned long unused) cvm_oct_free_work(work); } } - /* Restore the original POW group mask */ cvmx_write_csr(CVMX_POW_PP_GRP_MSKX(coreid), old_group_mask); if (USE_ASYNC_IOBDMA) { /* Restore the scratch area */ cvmx_scratch_write64(CVMX_SCR_SCRATCH, old_scratch); } + cvm_oct_rx_refill_pool(0); - if (USE_SKBUFFS_IN_HW) { - /* Refill the packet buffer pool */ - number_to_free = - cvmx_fau_fetch_and_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, 0); - - if (number_to_free > 0) { - cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, - -number_to_free); - num_freed = - cvm_oct_mem_fill_fpa(CVMX_FPA_PACKET_POOL, - CVMX_FPA_PACKET_POOL_SIZE, - number_to_free); - if (num_freed != number_to_free) { - cvmx_fau_atomic_add32 - (FAU_NUM_PACKET_BUFFERS_TO_FREE, - number_to_free - num_freed); - } - } + if (rx_count < budget && napi != NULL) { + /* No more work */ + napi_complete(napi); + cvm_oct_no_more_work(); } + return rx_count; } +#ifdef CONFIG_NET_POLL_CONTROLLER +/** + * This is called when the kernel needs to manually poll the + * device. + * + * @dev: Device to poll. Unused + */ +void cvm_oct_poll_controller(struct net_device *dev) +{ + cvm_oct_napi_poll(NULL, 16); +} +#endif + void cvm_oct_rx_initialize(void) { int i; - /* Initialize all of the tasklets */ - for (i = 0; i < NR_CPUS; i++) - tasklet_init(&cvm_oct_tasklet[i].t, cvm_oct_tasklet_rx, 0); + struct net_device *dev_for_napi = NULL; + union cvmx_pow_wq_int_thrx int_thr; + union cvmx_pow_wq_int_pc int_pc; + + for (i = 0; i < TOTAL_NUMBER_OF_PORTS; i++) { + if (cvm_oct_device[i]) { + dev_for_napi = cvm_oct_device[i]; + break; + } + } + + if (NULL == dev_for_napi) + panic("No net_devices were allocated."); + + if (max_rx_cpus > 1 && max_rx_cpus < num_online_cpus()) + atomic_set(&core_state.available_cores, max_rx_cpus); + else + atomic_set(&core_state.available_cores, num_online_cpus()); + core_state.baseline_cores = atomic_read(&core_state.available_cores); + + core_state.cpu_state = CPU_MASK_NONE; + for_each_possible_cpu(i) { + netif_napi_add(dev_for_napi, &cvm_oct_napi[i].napi, + cvm_oct_napi_poll, rx_napi_weight); + napi_enable(&cvm_oct_napi[i].napi); + } + /* Register an IRQ hander for to receive POW interrupts */ + i = request_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group, + cvm_oct_do_interrupt, 0, "Ethernet", cvm_oct_device); + + if (i) + panic("Could not acquire Ethernet IRQ %d\n", + OCTEON_IRQ_WORKQ0 + pow_receive_group); + + disable_irq_nosync(OCTEON_IRQ_WORKQ0 + pow_receive_group); + + int_thr.u64 = 0; + int_thr.s.tc_en = 1; + int_thr.s.tc_thr = 1; + /* Enable POW interrupt when our port has at least one packet */ + cvmx_write_csr(CVMX_POW_WQ_INT_THRX(pow_receive_group), int_thr.u64); + + int_pc.u64 = 0; + int_pc.s.pc_thr = 5; + cvmx_write_csr(CVMX_POW_WQ_INT_PC, int_pc.u64); + + + /* Scheduld NAPI now. This will indirectly enable interrupts. */ + cvm_oct_enable_one_cpu(); } void cvm_oct_rx_shutdown(void) { int i; - /* Shutdown all of the tasklets */ - for (i = 0; i < NR_CPUS; i++) - tasklet_kill(&cvm_oct_tasklet[i].t); + /* Shutdown all of the NAPIs */ + for_each_possible_cpu(i) + netif_napi_del(&cvm_oct_napi[i].napi); } diff --git a/drivers/staging/octeon/ethernet-rx.h b/drivers/staging/octeon/ethernet-rx.h index a9b72b87a7a6..a0743b85d54e 100644 --- a/drivers/staging/octeon/ethernet-rx.h +++ b/drivers/staging/octeon/ethernet-rx.h @@ -24,10 +24,29 @@ * This file may also be available under a different license from Cavium. * Contact Cavium Networks for more information *********************************************************************/ +#include "cvmx-fau.h" -irqreturn_t cvm_oct_do_interrupt(int cpl, void *dev_id); void cvm_oct_poll_controller(struct net_device *dev); -void cvm_oct_tasklet_rx(unsigned long unused); - void cvm_oct_rx_initialize(void); void cvm_oct_rx_shutdown(void); + +static inline void cvm_oct_rx_refill_pool(int fill_threshold) +{ + int number_to_free; + int num_freed; + /* Refill the packet buffer pool */ + number_to_free = + cvmx_fau_fetch_and_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, 0); + + if (number_to_free > fill_threshold) { + cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, + -number_to_free); + num_freed = cvm_oct_mem_fill_fpa(CVMX_FPA_PACKET_POOL, + CVMX_FPA_PACKET_POOL_SIZE, + number_to_free); + if (num_freed != number_to_free) { + cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, + number_to_free - num_freed); + } + } +} diff --git a/drivers/staging/octeon/ethernet.c b/drivers/staging/octeon/ethernet.c index 973178a80c93..9f5b7419e777 100644 --- a/drivers/staging/octeon/ethernet.c +++ b/drivers/staging/octeon/ethernet.c @@ -104,6 +104,16 @@ MODULE_PARM_DESC(pow_send_list, "\n" "\t\"eth2,spi3,spi7\" would cause these three devices to transmit\n" "\tusing the pow_send_group."); +int max_rx_cpus = -1; +module_param(max_rx_cpus, int, 0444); +MODULE_PARM_DESC(max_rx_cpus, "\n" + "\t\tThe maximum number of CPUs to use for packet reception.\n" + "\t\tUse -1 to use all available CPUs."); + +int rx_napi_weight = 32; +module_param(rx_napi_weight, int, 0444); +MODULE_PARM_DESC(rx_napi_weight, "The NAPI WEIGHT parameter."); + /* * The offset from mac_addr_base that should be used for the next port * that is configured. By convention, if any mgmt ports exist on the @@ -148,6 +158,15 @@ static void cvm_do_timer(unsigned long arg) mod_timer(&cvm_oct_poll_timer, jiffies + HZ/50); } else { port = 0; + /* + * FPA 0 may have been drained, try to refill it if we + * need more than num_packet_buffers / 2, otherwise + * normal receive processing will refill it. If it + * were drained, no packets could be received so + * cvm_oct_napi_poll would never be invoked to do the + * refill. + */ + cvm_oct_rx_refill_pool(num_packet_buffers / 2); /* * All ports have been polled. Start the next iteration through * the ports in one second. @@ -161,7 +180,6 @@ static void cvm_do_timer(unsigned long arg) */ static __init void cvm_oct_configure_common_hw(void) { - int r; /* Setup the FPA */ cvmx_fpa_enable(); cvm_oct_mem_fill_fpa(CVMX_FPA_PACKET_POOL, CVMX_FPA_PACKET_POOL_SIZE, @@ -176,17 +194,6 @@ static __init void cvm_oct_configure_common_hw(void) cvmx_helper_setup_red(num_packet_buffers / 4, num_packet_buffers / 8); - /* Register an IRQ hander for to receive POW interrupts */ - r = request_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group, - cvm_oct_do_interrupt, IRQF_SHARED, "Ethernet", - cvm_oct_device); - -#if defined(CONFIG_SMP) && 0 - if (USE_MULTICORE_RECEIVE) { - irq_set_affinity(OCTEON_IRQ_WORKQ0 + pow_receive_group, - cpu_online_mask); - } -#endif } /** @@ -616,7 +623,6 @@ static int __init cvm_oct_init_module(void) cvm_oct_mac_addr_offset = 0; cvm_oct_proc_initialize(); - cvm_oct_rx_initialize(); cvm_oct_configure_common_hw(); cvmx_helper_initialize_packet_io_global(); @@ -781,25 +787,7 @@ static int __init cvm_oct_init_module(void) } } - if (INTERRUPT_LIMIT) { - /* - * Set the POW timer rate to give an interrupt at most - * INTERRUPT_LIMIT times per second. - */ - cvmx_write_csr(CVMX_POW_WQ_INT_PC, - octeon_bootinfo->eclock_hz / (INTERRUPT_LIMIT * - 16 * 256) << 8); - - /* - * Enable POW timer interrupt. It will count when - * there are packets available. - */ - cvmx_write_csr(CVMX_POW_WQ_INT_THRX(pow_receive_group), - 0x1ful << 24); - } else { - /* Enable POW interrupt when our port has at least one packet */ - cvmx_write_csr(CVMX_POW_WQ_INT_THRX(pow_receive_group), 0x1001); - } + cvm_oct_rx_initialize(); /* Enable the poll timer for checking RGMII status */ init_timer(&cvm_oct_poll_timer); diff --git a/drivers/staging/octeon/octeon-ethernet.h b/drivers/staging/octeon/octeon-ethernet.h index 203c6a920af5..40b695615431 100644 --- a/drivers/staging/octeon/octeon-ethernet.h +++ b/drivers/staging/octeon/octeon-ethernet.h @@ -98,4 +98,7 @@ extern int pow_receive_group; extern char pow_send_list[]; extern struct net_device *cvm_oct_device[]; +extern int max_rx_cpus; +extern int rx_napi_weight; + #endif