diff options
author | Devesh Sharma <devesh.sharma@avagotech.com> | 2015-12-24 13:14:07 -0500 |
---|---|---|
committer | Doug Ledford <dledford@redhat.com> | 2016-01-19 14:00:47 -0500 |
commit | 3b1ea43009f2aca9f8ff0dd6540f6701e0871baf (patch) | |
tree | c3d915f0e9381614b3dc12c2f1f765ed5088ab89 /drivers/infiniband/hw/ocrdma/ocrdma_hw.c | |
parent | RDMA/ocrdma: Dispatch only port event when port state changes (diff) | |
download | linux-dev-3b1ea43009f2aca9f8ff0dd6540f6701e0871baf.tar.xz linux-dev-3b1ea43009f2aca9f8ff0dd6540f6701e0871baf.zip |
RDMA/ocrdma: Depend on async link events from CNA
Recently Dough Ledford reported a deadlock happening
between ocrdma-load sequence and NetworkManager service
issuing "open" on be2net interface.
The deadlock happens when any be2net hook (e.g. open/close) is called
in parallel to insmod ocrdma.ko.
A. be2net is sending administrative open/close event to ocrdma holding
device_list_mutex. It does this from ndo_open/ndo_stop hooks of be2net.
So sequence of locks is rtnl_lock---> device_list lock
B. When new ocrdma roce device gets registered, infiniband stack now
takes rtnl_lock in ib_register_device() in GID initialization routines.
So sequence of locks in this path is device_list lock ---> rtnl_lock.
This improper locking sequence causes deadlock.
With this patch we stop using administrative open and close events
injected by be2net driver. These events were used to dispatch PORT_ACTIVE
and PORT_ERROR events to the IB-stack. This patch implements a logic
to receive async-link-events generated from CNA whenever link-state-change
is detected. Now on, these async-events will be used to dispatch
PORT_ACTIVE and PORT_ERROR events to IB-stack.
Depending on async-events from CNA removes the need to hold device-list-mutex
and thus breaks the busy-wait scenario.
Reported-by: Doug Ledford <dledford@redhat.com>
CC: Sathya Perla <sathya.perla@avagotech.com>
Signed-off-by: Padmanabh Ratnakar <padmanabh.ratnakar@avagotech.com>
Signed-off-by: Selvin Xavier <selvin.xavier@avagotech.com>
Signed-off-by: Devesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Diffstat (limited to 'drivers/infiniband/hw/ocrdma/ocrdma_hw.c')
-rw-r--r-- | drivers/infiniband/hw/ocrdma/ocrdma_hw.c | 42 |
1 files changed, 35 insertions, 7 deletions
diff --git a/drivers/infiniband/hw/ocrdma/ocrdma_hw.c b/drivers/infiniband/hw/ocrdma/ocrdma_hw.c index 4fc2bb49c28e..283ca842ff74 100644 --- a/drivers/infiniband/hw/ocrdma/ocrdma_hw.c +++ b/drivers/infiniband/hw/ocrdma/ocrdma_hw.c @@ -579,6 +579,8 @@ static int ocrdma_mbx_create_mq(struct ocrdma_dev *dev, cmd->async_event_bitmap = BIT(OCRDMA_ASYNC_GRP5_EVE_CODE); cmd->async_event_bitmap |= BIT(OCRDMA_ASYNC_RDMA_EVE_CODE); + /* Request link events on this MQ. */ + cmd->async_event_bitmap |= BIT(OCRDMA_ASYNC_LINK_EVE_CODE); cmd->async_cqid_ringsize = cq->id; cmd->async_cqid_ringsize |= (ocrdma_encoded_q_len(mq->len) << @@ -819,20 +821,42 @@ static void ocrdma_process_grp5_aync(struct ocrdma_dev *dev, } } +static void ocrdma_process_link_state(struct ocrdma_dev *dev, + struct ocrdma_ae_mcqe *cqe) +{ + struct ocrdma_ae_lnkst_mcqe *evt; + u8 lstate; + + evt = (struct ocrdma_ae_lnkst_mcqe *)cqe; + lstate = ocrdma_get_ae_link_state(evt->speed_state_ptn); + + if (!(lstate & OCRDMA_AE_LSC_LLINK_MASK)) + return; + + if (dev->flags & OCRDMA_FLAGS_LINK_STATUS_INIT) + ocrdma_update_link_state(dev, (lstate & OCRDMA_LINK_ST_MASK)); +} + static void ocrdma_process_acqe(struct ocrdma_dev *dev, void *ae_cqe) { /* async CQE processing */ struct ocrdma_ae_mcqe *cqe = ae_cqe; u32 evt_code = (cqe->valid_ae_event & OCRDMA_AE_MCQE_EVENT_CODE_MASK) >> OCRDMA_AE_MCQE_EVENT_CODE_SHIFT; - - if (evt_code == OCRDMA_ASYNC_RDMA_EVE_CODE) + switch (evt_code) { + case OCRDMA_ASYNC_LINK_EVE_CODE: + ocrdma_process_link_state(dev, cqe); + break; + case OCRDMA_ASYNC_RDMA_EVE_CODE: ocrdma_dispatch_ibevent(dev, cqe); - else if (evt_code == OCRDMA_ASYNC_GRP5_EVE_CODE) + break; + case OCRDMA_ASYNC_GRP5_EVE_CODE: ocrdma_process_grp5_aync(dev, cqe); - else + break; + default: pr_err("%s(%d) invalid evt code=0x%x\n", __func__, dev->id, evt_code); + } } static void ocrdma_process_mcqe(struct ocrdma_dev *dev, struct ocrdma_mcqe *cqe) @@ -1363,7 +1387,8 @@ mbx_err: return status; } -int ocrdma_mbx_get_link_speed(struct ocrdma_dev *dev, u8 *lnk_speed) +int ocrdma_mbx_get_link_speed(struct ocrdma_dev *dev, u8 *lnk_speed, + u8 *lnk_state) { int status = -ENOMEM; struct ocrdma_get_link_speed_rsp *rsp; @@ -1384,8 +1409,11 @@ int ocrdma_mbx_get_link_speed(struct ocrdma_dev *dev, u8 *lnk_speed) goto mbx_err; rsp = (struct ocrdma_get_link_speed_rsp *)cmd; - *lnk_speed = (rsp->pflt_pps_ld_pnum & OCRDMA_PHY_PS_MASK) - >> OCRDMA_PHY_PS_SHIFT; + if (lnk_speed) + *lnk_speed = (rsp->pflt_pps_ld_pnum & OCRDMA_PHY_PS_MASK) + >> OCRDMA_PHY_PS_SHIFT; + if (lnk_state) + *lnk_state = (rsp->res_lnk_st & OCRDMA_LINK_ST_MASK); mbx_err: kfree(cmd); |