From ab69b3cf1219e0d07bb4ea373f36b1de38af531c Mon Sep 17 00:00:00 2001 From: John Gregor Date: Wed, 7 May 2008 11:01:10 -0700 Subject: [PATCH] IB/ipath: Fix SDMA error recovery in absence of link status change What's fixed: in ipath_cancel_sends() We need to unconditionally set ABORTING. So, swap the tests so the set_bit() isn't shadowed by the &&. If we've disarmed the piobufs, then we need to unconditionally set DISARMED. So, move it out from the overly protective if at the bottom. in sdma_abort_task() Abort_task was written knowing that the SDMA engine would always be reset (and restarted) on error. A recent change broke that fundamental assumption by taking the restart portion and making it conditional on a link status change. But, SDMA can go boom without a link status change in some conditions. Signed-off-by: John Gregor Signed-off-by: Roland Dreier --- drivers/infiniband/hw/ipath/ipath_driver.c | 8 +++--- drivers/infiniband/hw/ipath/ipath_sdma.c | 31 +++++++++++++++++----- 2 files changed, 29 insertions(+), 10 deletions(-) diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c index 2036d38fac47..ce7b7c34360e 100644 --- a/drivers/infiniband/hw/ipath/ipath_driver.c +++ b/drivers/infiniband/hw/ipath/ipath_driver.c @@ -1898,8 +1898,8 @@ void ipath_cancel_sends(struct ipath_devdata *dd, int restore_sendctrl) spin_lock_irqsave(&dd->ipath_sdma_lock, flags); skip_cancel = - !test_bit(IPATH_SDMA_DISABLED, statp) && - test_and_set_bit(IPATH_SDMA_ABORTING, statp); + test_and_set_bit(IPATH_SDMA_ABORTING, statp) + && !test_bit(IPATH_SDMA_DISABLED, statp); spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags); if (skip_cancel) goto bail; @@ -1930,6 +1930,9 @@ void ipath_cancel_sends(struct ipath_devdata *dd, int restore_sendctrl) ipath_disarm_piobufs(dd, 0, dd->ipath_piobcnt2k + dd->ipath_piobcnt4k); + if (dd->ipath_flags & IPATH_HAS_SEND_DMA) + set_bit(IPATH_SDMA_DISARMED, &dd->ipath_sdma_status); + if (restore_sendctrl) { /* else done by caller later if needed */ spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags); @@ -1949,7 +1952,6 @@ void ipath_cancel_sends(struct ipath_devdata *dd, int restore_sendctrl) /* only wait so long for intr */ dd->ipath_sdma_abort_intr_timeout = jiffies + HZ; dd->ipath_sdma_reset_wait = 200; - __set_bit(IPATH_SDMA_DISARMED, &dd->ipath_sdma_status); if (!test_bit(IPATH_SDMA_SHUTDOWN, &dd->ipath_sdma_status)) tasklet_hi_schedule(&dd->ipath_sdma_abort_task); spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags); diff --git a/drivers/infiniband/hw/ipath/ipath_sdma.c b/drivers/infiniband/hw/ipath/ipath_sdma.c index 0d07682c7310..3697449c1ba4 100644 --- a/drivers/infiniband/hw/ipath/ipath_sdma.c +++ b/drivers/infiniband/hw/ipath/ipath_sdma.c @@ -308,13 +308,15 @@ static void sdma_abort_task(unsigned long opaque) spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags); /* - * Don't restart sdma here. Wait until link is up to ACTIVE. - * VL15 MADs used to bring the link up use PIO, and multiple - * link transitions otherwise cause the sdma engine to be + * Don't restart sdma here (with the exception + * below). Wait until link is up to ACTIVE. VL15 MADs + * used to bring the link up use PIO, and multiple link + * transitions otherwise cause the sdma engine to be * stopped and started multiple times. - * The disable is done here, including the shadow, so the - * state is kept consistent. - * See ipath_restart_sdma() for the actual starting of sdma. + * The disable is done here, including the shadow, + * so the state is kept consistent. + * See ipath_restart_sdma() for the actual starting + * of sdma. */ spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags); dd->ipath_sendctrl &= ~INFINIPATH_S_SDMAENABLE; @@ -326,6 +328,13 @@ static void sdma_abort_task(unsigned long opaque) /* make sure I see next message */ dd->ipath_sdma_abort_jiffies = 0; + /* + * Not everything that takes SDMA offline is a link + * status change. If the link was up, restart SDMA. + */ + if (dd->ipath_flags & IPATH_LINKACTIVE) + ipath_restart_sdma(dd); + goto done; } @@ -427,7 +436,12 @@ int setup_sdma(struct ipath_devdata *dd) goto done; } - dd->ipath_sdma_status = 0; + /* + * Set initial status as if we had been up, then gone down. + * This lets initial start on transition to ACTIVE be the + * same as restart after link flap. + */ + dd->ipath_sdma_status = IPATH_SDMA_ABORT_ABORTED; dd->ipath_sdma_abort_jiffies = 0; dd->ipath_sdma_generation = 0; dd->ipath_sdma_descq_tail = 0; @@ -618,6 +632,9 @@ void ipath_restart_sdma(struct ipath_devdata *dd) ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch); spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags); + /* notify upper layers */ + ipath_ib_piobufavail(dd->verbs_dev); + bail: return; } -- 2.39.5