RE: [PATCH] s2io: add PCI error recovery support

From: Ramkrishna Vepa
Date: Tue Mar 06 2007 - 19:43:15 EST


Jeff,

Please apply and forward this patch upstream.

Ram
> -----Original Message-----
> From: Ramkrishna Vepa
> Sent: Monday, March 05, 2007 2:34 PM
> To: 'Linas Vepstas'
> Cc: Wen Xiong; linux-kernel@xxxxxxxxxxxxxxx; linux-
> pci@xxxxxxxxxxxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; Jeff Garzik;
Andrew
> Morton
> Subject: RE: [PATCH] s2io: add PCI error recovery support
>
> Comments on this patch -
>
> 1. device_close_flag is unused and is not required.
> > +static pci_ers_result_t s2io_io_error_detected(struct pci_dev
*pdev,
> > + pci_channel_state_t
> state)
> > +{
> ...
> > + do_s2io_card_down(sp, 0);
> > + sp->device_close_flag = TRUE; /* Device is shut down.
*/
>
> 2. s2io_reset can fail to reset the device. Ideally s2io_reset should
> return a failure in this case (return is void now) and in this case
could
> s2io_io_slot_reset() be called again, maybe try thrice, in total,
before
> failing to reset the slot?
>
> Ram
> > -----Original Message-----
> > From: Linas Vepstas [mailto:linas@xxxxxxxxxxxxxx]
> > Sent: Thursday, February 15, 2007 3:09 PM
> > To: Ramkrishna Vepa; Raghavendra Koushik; Ananda Raju
> > Cc: Wen Xiong; linux-kernel@xxxxxxxxxxxxxxx; linux-
> > pci@xxxxxxxxxxxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; Jeff Garzik;
> Andrew
> > Morton
> > Subject: [PATCH] s2io: add PCI error recovery support
> >
> >
> > Koushik, Raju,
> >
> > Please review, comment, and if you find this acceptable,
> > please forward upstream. This patch incorporates all of
> > fixes resulting from the last set of discussions, circa
> > November 2006.
> >
> > --linas
> >
> > This patch adds PCI error recovery support to the
> > s2io 10-Gigabit ethernet device driver. Fourth revision,
> > blocks interrupts and the watchdog. Adds a flag to
> > s2io_down(), to avoid doing I/O when PCI bus is offline.
> >
> > Tested, seems to work well.
> >
> > Signed-off-by: Linas Vepstas <linas@xxxxxxxxxxxxxx>
> > Acked-by: Ramkrishna Vepa <Ramkrishna.Vepa@xxxxxxxxxxxx>
> > Cc: Raghavendra Koushik <raghavendra.koushik@xxxxxxxxxxxx>
> > Cc: Ananda Raju <Ananda.Raju@xxxxxxxxxxxx>
> > Cc: Wen Xiong <wenxiong@xxxxxxxxxx>
> >
> > ----
> > drivers/net/s2io.c | 116
> > ++++++++++++++++++++++++++++++++++++++++++++++++++---
> > drivers/net/s2io.h | 5 ++
> > 2 files changed, 116 insertions(+), 5 deletions(-)
> >
> > Index: linux-2.6.20-git4/drivers/net/s2io.c
> > ===================================================================
> > --- linux-2.6.20-git4.orig/drivers/net/s2io.c 2007-02-15
> > 15:39:35.000000000 -0600
> > +++ linux-2.6.20-git4/drivers/net/s2io.c 2007-02-15
> 16:15:10.000000000 -
> > 0600
> > @@ -435,11 +435,18 @@ static struct pci_device_id s2io_tbl[] _
> >
> > MODULE_DEVICE_TABLE(pci, s2io_tbl);
> >
> > +static struct pci_error_handlers s2io_err_handler = {
> > + .error_detected = s2io_io_error_detected,
> > + .slot_reset = s2io_io_slot_reset,
> > + .resume = s2io_io_resume,
> > +};
> > +
> > static struct pci_driver s2io_driver = {
> > .name = "S2IO",
> > .id_table = s2io_tbl,
> > .probe = s2io_init_nic,
> > .remove = __devexit_p(s2io_rem_nic),
> > + .err_handler = &s2io_err_handler,
> > };
> >
> > /* A simplifier macro used both by init and free shared_mem Fns().
*/
> > @@ -2577,6 +2584,9 @@ static void s2io_netpoll(struct net_devi
> > u64 val64 = 0xFFFFFFFFFFFFFFFFULL;
> > int i;
> >
> > + if (pci_channel_offline(nic->pdev))
> > + return;
> > +
> > disable_irq(dev->irq);
> >
> > atomic_inc(&nic->isr_cnt);
> > @@ -3079,6 +3089,8 @@ static void alarm_intr_handler(struct s2
> > int i;
> > if (atomic_read(&nic->card_state) == CARD_DOWN)
> > return;
> > + if (pci_channel_offline(nic->pdev))
> > + return;
> > nic->mac_control.stats_info->sw_stat.ring_full_cnt = 0;
> > /* Handling the XPAK counters update */
> > if(nic->mac_control.stats_info->xpak_stat.xpak_timer_count <
72000)
> > {
> > @@ -4117,6 +4129,10 @@ static irqreturn_t s2io_isr(int irq, voi
> > struct mac_info *mac_control;
> > struct config_param *config;
> >
> > + /* Pretend we handled any irq's from a disconnected card */
> > + if (pci_channel_offline(sp->pdev))
> > + return IRQ_NONE;
> > +
> > atomic_inc(&sp->isr_cnt);
> > mac_control = &sp->mac_control;
> > config = &sp->config;
> > @@ -6188,7 +6204,7 @@ static void s2io_rem_isr(struct s2io_nic
> > } while(cnt < 5);
> > }
> >
> > -static void s2io_card_down(struct s2io_nic * sp)
> > +static void do_s2io_card_down(struct s2io_nic * sp, int do_io)
> > {
> > int cnt = 0;
> > struct XENA_dev_config __iomem *bar0 = sp->bar0;
> > @@ -6203,7 +6219,8 @@ static void s2io_card_down(struct s2io_n
> > atomic_set(&sp->card_state, CARD_DOWN);
> >
> > /* disable Tx and Rx traffic on the NIC */
> > - stop_nic(sp);
> > + if (do_io)
> > + stop_nic(sp);
> >
> > s2io_rem_isr(sp);
> >
> > @@ -6211,7 +6228,7 @@ static void s2io_card_down(struct s2io_n
> > tasklet_kill(&sp->task);
> >
> > /* Check if the device is Quiescent and then Reset the NIC */
> > - do {
> > + while(do_io) {
> > /* As per the HW requirement we need to replenish the
> > * receive buffer to avoid the ring bump. Since there is
> > * no intention of processing the Rx frame at this
pointwe are
> > @@ -6236,8 +6253,9 @@ static void s2io_card_down(struct s2io_n
> > (unsigned long long) val64);
> > break;
> > }
> > - } while (1);
> > - s2io_reset(sp);
> > + }
> > + if (do_io)
> > + s2io_reset(sp);
> >
> > spin_lock_irqsave(&sp->tx_lock, flags);
> > /* Free all Tx buffers */
> > @@ -6252,6 +6270,11 @@ static void s2io_card_down(struct s2io_n
> > clear_bit(0, &(sp->link_state));
> > }
> >
> > +static void s2io_card_down(struct s2io_nic * sp)
> > +{
> > + do_s2io_card_down(sp, 1);
> > +}
> > +
> > static int s2io_card_up(struct s2io_nic * sp)
> > {
> > int i, ret = 0;
> > @@ -7536,3 +7559,86 @@ static void lro_append_pkt(struct s2io_n
> > sp->mac_control.stats_info->sw_stat.clubbed_frms_cnt++;
> > return;
> > }
> > +
> > +/**
> > + * s2io_io_error_detected - called when PCI error is detected
> > + * @pdev: Pointer to PCI device
> > + * @state: The current pci conneection state
> > + *
> > + * This function is called after a PCI bus error affecting
> > + * this device has been detected.
> > + */
> > +static pci_ers_result_t s2io_io_error_detected(struct pci_dev
*pdev,
> > + pci_channel_state_t
> state)
> > +{
> > + struct net_device *netdev = pci_get_drvdata(pdev);
> > + struct s2io_nic *sp = netdev->priv;
> > +
> > + netif_device_detach(netdev);
> > +
> > + if (netif_running(netdev)) {
> > + /* Bring down the card, while avoiding PCI I/O */
> > + do_s2io_card_down(sp, 0);
> > + sp->device_close_flag = TRUE; /* Device is shut down.
*/
> > + }
> > + pci_disable_device(pdev);
> > +
> > + return PCI_ERS_RESULT_NEED_RESET;
> > +}
> > +
> > +/**
> > + * s2io_io_slot_reset - called after the pci bus has been reset.
> > + * @pdev: Pointer to PCI device
> > + *
> > + * Restart the card from scratch, as if from a cold-boot.
> > + * At this point, the card has exprienced a hard reset,
> > + * followed by fixups by BIOS, and has its config space
> > + * set up identically to what it was at cold boot.
> > + */
> > +static pci_ers_result_t s2io_io_slot_reset(struct pci_dev *pdev)
> > +{
> > + struct net_device *netdev = pci_get_drvdata(pdev);
> > + struct s2io_nic *sp = netdev->priv;
> > +
> > + if (pci_enable_device(pdev)) {
> > + printk(KERN_ERR "s2io: "
> > + "Cannot re-enable PCI device after reset.\n");
> > + return PCI_ERS_RESULT_DISCONNECT;
> > + }
> > +
> > + pci_set_master(pdev);
> > + s2io_reset(sp);
> > +
> > + return PCI_ERS_RESULT_RECOVERED;
> > +}
> > +
> > +/**
> > + * s2io_io_resume - called when traffic can start flowing again.
> > + * @pdev: Pointer to PCI device
> > + *
> > + * This callback is called when the error recovery driver tells
> > + * us that its OK to resume normal operation.
> > + */
> > +static void s2io_io_resume(struct pci_dev *pdev)
> > +{
> > + struct net_device *netdev = pci_get_drvdata(pdev);
> > + struct s2io_nic *sp = netdev->priv;
> > +
> > + if (netif_running(netdev)) {
> > + if (s2io_card_up(sp)) {
> > + printk(KERN_ERR "s2io: "
> > + "Can't bring device back up after
reset.\n");
> > + return;
> > + }
> > +
> > + if (s2io_set_mac_addr(netdev, netdev->dev_addr) ==
FAILURE) {
> > + s2io_card_down(sp);
> > + printk(KERN_ERR "s2io: "
> > + "Can't resetore mac addr after
reset.\n");
> > + return;
> > + }
> > + }
> > +
> > + netif_device_attach(netdev);
> > + netif_wake_queue(netdev);
> > +}
> > Index: linux-2.6.20-git4/drivers/net/s2io.h
> > ===================================================================
> > --- linux-2.6.20-git4.orig/drivers/net/s2io.h 2007-02-15
> > 15:39:35.000000000 -0600
> > +++ linux-2.6.20-git4/drivers/net/s2io.h 2007-02-15
> 16:59:40.000000000 -
> > 0600
> > @@ -1020,6 +1020,11 @@ static void update_L3L4_header(struct s2
> > static void lro_append_pkt(struct s2io_nic *sp, struct lro *lro,
> > struct sk_buff *skb, u32 tcp_len);
> >
> > +static pci_ers_result_t s2io_io_error_detected(struct pci_dev
*pdev,
> > + pci_channel_state_t
state);
> > +static pci_ers_result_t s2io_io_slot_reset(struct pci_dev *pdev);
> > +static void s2io_io_resume(struct pci_dev *pdev);
> > +
> > #define s2io_tcp_mss(skb) skb_shinfo(skb)->gso_size
> > #define s2io_udp_mss(skb) skb_shinfo(skb)->gso_size
> > #define s2io_offload_type(skb) skb_shinfo(skb)->gso_type
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/