> On Jul 20, 2017, at 5:44 PM, Benjamin Poirier <bpoir...@suse.com> wrote:
>
> [snip]
> Could you please test the following patch and let me know if it:
> 1) reduces the interrupt rate of the Other msi-x vector
> 2) avoids the link flaps
> or
> 3) logs some dmesg warnings of the form "Other interrupt with unhandled [...]"
> In this case, please paste icr values printed.
>
> Thanks
>
> diff --git a/drivers/net/ethernet/intel/e1000e/defines.h
> b/drivers/net/ethernet/intel/e1000e/defines.h
> index 0641c0098738..afb7ebe20b24 100644
> --- a/drivers/net/ethernet/intel/e1000e/defines.h
> +++ b/drivers/net/ethernet/intel/e1000e/defines.h
> @@ -398,6 +398,7 @@
> #define E1000_ICR_LSC 0x00000004 /* Link Status Change */
> #define E1000_ICR_RXSEQ 0x00000008 /* Rx sequence error */
> #define E1000_ICR_RXDMT0 0x00000010 /* Rx desc min. threshold (0) */
> +#define E1000_ICR_RXO 0x00000040 /* Receiver Overrun */
> #define E1000_ICR_RXT0 0x00000080 /* Rx timer intr (ring 0) */
> #define E1000_ICR_ECCER 0x00400000 /* Uncorrectable ECC Error */
> /* If this bit asserted, the driver should claim the interrupt */
> diff --git a/drivers/net/ethernet/intel/e1000e/e1000.h
> b/drivers/net/ethernet/intel/e1000e/e1000.h
> index c7c994eb410e..f7b46eba3efb 100644
> --- a/drivers/net/ethernet/intel/e1000e/e1000.h
> +++ b/drivers/net/ethernet/intel/e1000e/e1000.h
> @@ -351,6 +351,10 @@ struct e1000_adapter {
> s32 ptp_delta;
>
> u16 eee_advert;
> +
> + unsigned int uh_count;
> + u32 uh_values[16];
> + unsigned int uh_values_nb;
> };
>
> struct e1000_info {
> diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c
> b/drivers/net/ethernet/intel/e1000e/netdev.c
> index b3679728caac..46697338c0e1 100644
> --- a/drivers/net/ethernet/intel/e1000e/netdev.c
> +++ b/drivers/net/ethernet/intel/e1000e/netdev.c
> @@ -46,6 +46,8 @@
>
> #include "e1000.h"
>
> +DEFINE_RATELIMIT_STATE(other_uh_ratelimit_state, HZ, 1);
> +
> #define DRV_EXTRAVERSION "-k"
>
> #define DRV_VERSION "3.2.6" DRV_EXTRAVERSION
> @@ -1904,12 +1906,60 @@ static irqreturn_t e1000_msix_other(int
> __always_unused irq, void *data)
> struct net_device *netdev = data;
> struct e1000_adapter *adapter = netdev_priv(netdev);
> struct e1000_hw *hw = &adapter->hw;
> + u32 icr;
> + bool enable = true;
> + bool handled = false;
> + unsigned int i;
>
> - hw->mac.get_link_status = true;
> + icr = er32(ICR);
> + if (icr & E1000_ICR_RXO) {
> + ew32(ICR, E1000_ICR_RXO);
> + enable = false;
> + /* napi poll will re-enable Other, make sure it runs */
> + if (napi_schedule_prep(&adapter->napi)) {
> + adapter->total_rx_bytes = 0;
> + adapter->total_rx_packets = 0;
> + __napi_schedule(&adapter->napi);
> + }
> + handled = true;
> + }
> + if (icr & E1000_ICR_LSC) {
> + ew32(ICR, E1000_ICR_LSC);
> + hw->mac.get_link_status = true;
> + /* guard against interrupt when we're going down */
> + if (!test_bit(__E1000_DOWN, &adapter->state)) {
> + mod_timer(&adapter->watchdog_timer, jiffies + 1);
> + }
> + handled = true;
> + }
>
> - /* guard against interrupt when we're going down */
> - if (!test_bit(__E1000_DOWN, &adapter->state)) {
> - mod_timer(&adapter->watchdog_timer, jiffies + 1);
> + if (!handled) {
> + adapter->uh_count++;
> + /* only print unseen icr values */
> + if (adapter->uh_values_nb < ARRAY_SIZE(adapter->uh_values)) {
> + for (i = 0; i < ARRAY_SIZE(adapter->uh_values); i++) {
> + if (adapter->uh_values[i] == icr) {
> + break;
> + }
> + }
> + if (i == ARRAY_SIZE(adapter->uh_values)) {
> + adapter->uh_values[adapter->uh_values_nb] =
> + icr;
> + adapter->uh_values_nb++;
> + netdev_warn(netdev,
> + "Other interrupt with unhandled icr
> 0x%08x\n",
> + icr);
> + }
> + }
> + }
> + if (adapter->uh_count && __ratelimit(&other_uh_ratelimit_state)) {
> + netdev_warn(netdev,
> + "Other interrupt with unhandled cause, count %u\n",
> + adapter->uh_count);
> + adapter->uh_count = 0;
> + }
> +
> + if (enable && !test_bit(__E1000_DOWN, &adapter->state)) {
> ew32(IMS, E1000_IMS_OTHER);
> }
>
> @@ -2681,7 +2731,8 @@ static int e1000e_poll(struct napi_struct *napi, int
> weight)
> napi_complete_done(napi, work_done);
> if (!test_bit(__E1000_DOWN, &adapter->state)) {
> if (adapter->msix_entries)
> - ew32(IMS, adapter->rx_ring->ims_val);
> + ew32(IMS, adapter->rx_ring->ims_val |
> + E1000_IMS_OTHER);
> else
> e1000_irq_enable(adapter);
> }
> @@ -4197,7 +4248,7 @@ static void e1000e_trigger_lsc(struct e1000_adapter
> *adapter)
> struct e1000_hw *hw = &adapter->hw;
>
> if (adapter->msix_entries)
> - ew32(ICS, E1000_ICS_OTHER);
> + ew32(ICS, E1000_ICS_LSC | E1000_ICS_OTHER);
> else
> ew32(ICS, E1000_ICS_LSC);
> }
> @@ -7572,6 +7623,8 @@ static int __init e1000_init_module(void)
> e1000e_driver_version);
> pr_info("Copyright(c) 1999 - 2015 Intel Corporation.\n");
>
> + ratelimit_set_flags(&other_uh_ratelimit_state,
> RATELIMIT_MSG_ON_RELEASE);
> +
> return pci_register_driver(&e1000_driver);
> }
> module_init(e1000_init_module);
We’ve been running this patch on a Lanner FW-7568 (Atom D525, 6x 82574L NICs)
under heavy load both with and without RPS enabled and have yet to see a single
link flap.
Is it going into linux-stable?
Thanks,
-Philip
