1 files changed, 46 insertions, 19 deletions

diff --git a/drivers/net/ethernet/sfc/selftest.c b/drivers/net/ethernet/sfc/selftest.c
index febe2a9e6211..dc330b9d9168 100644
--- a/drivers/net/ethernet/sfc/selftest.c
+++ b/drivers/net/ethernet/sfc/selftest.c
@@ -25,6 +25,16 @@
 #include "selftest.h"
 #include "workarounds.h"
 
+/* IRQ latency can be enormous because:
+ * - All IRQs may be disabled on a CPU for a *long* time by e.g. a
+ *   slow serial console or an old IDE driver doing error recovery
+ * - The PREEMPT_RT patches mostly deal with this, but also allow a
+ *   tasklet or normal task to be given higher priority than our IRQ
+ *   threads
+ * Try to avoid blaming the hardware for this.
+ */
+#define IRQ_TIMEOUT HZ
+
 /*
  * Loopback test packet structure
  *
@@ -77,6 +87,9 @@ struct efx_loopback_state {
         struct efx_loopback_payload payload;
 };
 
+/* How long to wait for all the packets to arrive (in ms) */
+#define LOOPBACK_TIMEOUT_MS 1000
+
 /**************************************************************************
  *
  * MII, NVRAM and register tests
@@ -130,6 +143,7 @@ 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)
 {
+        unsigned long timeout, wait;
         int cpu;
 
         netif_dbg(efx, drv, efx->net_dev, "testing interrupts\n");
@@ -140,13 +154,18 @@ static int efx_test_interrupts(struct efx_nic *efx,
         smp_wmb();
 
         efx_nic_generate_interrupt(efx);
+        timeout = jiffies + IRQ_TIMEOUT;
+        wait = 1;
 
         /* Wait for arrival of test interrupt. */
         netif_dbg(efx, drv, efx->net_dev, "waiting for test interrupt\n");
-        schedule_timeout_uninterruptible(HZ / 10);
-        cpu = ACCESS_ONCE(efx->last_irq_cpu);
-        if (cpu >= 0)
-                goto success;
+        do {
+                schedule_timeout_uninterruptible(wait);
+                cpu = ACCESS_ONCE(efx->last_irq_cpu);
+                if (cpu >= 0)
+                        goto success;
+                wait *= 2;
+        } while (time_before(jiffies, timeout));
 
         netif_err(efx, drv, efx->net_dev, "timed out waiting for interrupt\n");
         return -ETIMEDOUT;
@@ -165,29 +184,37 @@ static int efx_test_eventq_irq(struct efx_channel *channel,
         struct efx_nic *efx = channel->efx;
         unsigned int read_ptr;
         bool napi_ran, dma_seen, int_seen;
+        unsigned long timeout, wait;
 
         read_ptr = channel->eventq_read_ptr;
         channel->last_irq_cpu = -1;
         smp_wmb();
 
         efx_nic_generate_test_event(channel);
+        timeout = jiffies + IRQ_TIMEOUT;
+        wait = 1;
 
         /* Wait for arrival of interrupt.  NAPI processing may or may
          * not complete in time, but we can cope in any case.
          */
-        msleep(10);
-        napi_disable(&channel->napi_str);
-        if (channel->eventq_read_ptr != read_ptr) {
-                napi_ran = true;
-                dma_seen = true;
-                int_seen = true;
-        } else {
-                napi_ran = false;
-                dma_seen = efx_nic_event_present(channel);
-                int_seen = ACCESS_ONCE(channel->last_irq_cpu) >= 0;
-        }
-        napi_enable(&channel->napi_str);
-        efx_nic_eventq_read_ack(channel);
+        do {
+                schedule_timeout_uninterruptible(wait);
+
+                napi_disable(&channel->napi_str);
+                if (channel->eventq_read_ptr != read_ptr) {
+                        napi_ran = true;
+                        dma_seen = true;
+                        int_seen = true;
+                } else {
+                        napi_ran = false;
+                        dma_seen = efx_nic_event_present(channel);
+                        int_seen = ACCESS_ONCE(channel->last_irq_cpu) >= 0;
+                }
+                napi_enable(&channel->napi_str);
+                efx_nic_eventq_read_ack(channel);
+
+                wait *= 2;
+        } while (!(dma_seen && int_seen) && time_before(jiffies, timeout));
 
         tests->eventq_dma[channel->channel] = dma_seen ? 1 : -1;
         tests->eventq_int[channel->channel] = int_seen ? 1 : -1;
@@ -516,10 +543,10 @@ efx_test_loopback(struct efx_tx_queue *tx_queue,
                 begin_rc = efx_begin_loopback(tx_queue);
 
                 /* This will normally complete very quickly, but be
-                 * prepared to wait up to 100 ms. */
+                 * prepared to wait much longer. */
                 msleep(1);
                 if (!efx_poll_loopback(efx)) {
-                        msleep(100);
+                        msleep(LOOPBACK_TIMEOUT_MS);
                         efx_poll_loopback(efx);
                 }