staging: octeon-ethernet: drop multiple NAPI instances

[linux-drm-fsl-dcu.git] / drivers / staging / octeon / ethernet-rx.c

diff --git a/drivers/staging/octeon/ethernet-rx.c b/drivers/staging/octeon/ethernet-rx.c
index 44e372f096837b9e55288239ef3ddded0e74b805..1789a122100779e5953c8b4a8697311f5d6a7ce5 100644 (file)
--- a/drivers/staging/octeon/ethernet-rx.c
+++ b/drivers/staging/octeon/ethernet-rx.c
@@ -61,66 +61,7 @@
 
 #include <asm/octeon/cvmx-gmxx-defs.h>
 
-struct cvm_napi_wrapper {
-       struct napi_struct napi;
-} ____cacheline_aligned_in_smp;
-
-static struct cvm_napi_wrapper cvm_oct_napi[NR_CPUS] __cacheline_aligned_in_smp;
-
-struct cvm_oct_core_state {
-       int baseline_cores;
-       /*
-        * The number of additional cores that could be processing
-        * input packets.
-        */
-       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 int cvm_irq_cpu;
-
-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();
-
-       if (cpu == cvm_irq_cpu) {
-               enable_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group);
-               return;
-       }
-
-       cpu_clear(cpu, core_state.cpu_state);
-       atomic_add(1, &core_state.available_cores);
-}
+static struct napi_struct cvm_oct_napi;
 
 /**
  * cvm_oct_do_interrupt - interrupt handler.
@@ -132,8 +73,7 @@ static irqreturn_t cvm_oct_do_interrupt(int cpl, void *dev_id)
 {
        /* Disable the IRQ and start napi_poll. */
        disable_irq_nosync(OCTEON_IRQ_WORKQ0 + pow_receive_group);
-       cvm_irq_cpu = smp_processor_id();
-       cvm_oct_enable_napi(NULL);
+       napi_schedule(&cvm_oct_napi);
 
        return IRQ_HANDLED;
 }
@@ -285,23 +225,6 @@ static int cvm_oct_napi_poll(struct napi_struct *napi, int budget)
                        cvmx_pow_work_request_async_nocheck(CVMX_SCR_SCRATCH, CVMX_POW_NO_WAIT);
                        did_work_request = 1;
                }
-
-#ifndef CONFIG_RPS
-               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();
-               }
-#endif
                rx_count++;
 
                skb_in_hw = USE_SKBUFFS_IN_HW && work->word2.s.bufs == 1;
@@ -478,7 +401,7 @@ static int cvm_oct_napi_poll(struct napi_struct *napi, int budget)
        if (rx_count < budget && napi != NULL) {
                /* No more work */
                napi_complete(napi);
-               cvm_oct_no_more_work();
+               enable_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group);
        }
        return rx_count;
 }
@@ -513,18 +436,10 @@ void cvm_oct_rx_initialize(void)
        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);
-       }
+       netif_napi_add(dev_for_napi, &cvm_oct_napi, cvm_oct_napi_poll,
+                      rx_napi_weight);
+       napi_enable(&cvm_oct_napi);
+
        /* Register an IRQ handler to receive POW interrupts */
        i = request_irq(OCTEON_IRQ_WORKQ0 + pow_receive_group,
                        cvm_oct_do_interrupt, 0, "Ethernet", cvm_oct_device);
@@ -545,15 +460,11 @@ void cvm_oct_rx_initialize(void)
        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();
+       /* Schedule NAPI now. This will indirectly enable the interrupt. */
+       napi_schedule(&cvm_oct_napi);
 }
 
 void cvm_oct_rx_shutdown(void)
 {
-       int i;
-       /* Shutdown all of the NAPIs */
-       for_each_possible_cpu(i)
-               netif_napi_del(&cvm_oct_napi[i].napi);
+       netif_napi_del(&cvm_oct_napi);
 }