Re: [ofa-general][PATCH 3/4] SRP fail-over faster

[Vu Pham <vuhuong-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>]

Bart Van Assche wrote:
> On Fri, Oct 23, 2009 at 1:13 AM, Vu Pham <vuhuong-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org> wrote:
>   
>> [ ... ]
>>
>> Here is the updated patch which implement the device_loss_timeout for each target instead of module parameter. It also reflects changes from previous feedbacks. Please review
>>
>>
>>
>> Introducing device_loss_timeout per target granularity. Creating a timer to
>> clean up connection after device_loss_timeout expired. During
>> device_loss_timeout, the QP is in error state, srp will return DID_RESET
>> for outstanding I/Os and return FAILED for abort_cmd, reset_lun, and return
>> SUCCESS (without retrying reconnect) on reset_host
>>
>> Signed-off-by: Vu Pham <vu-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
>>
>> -----------------------------------------------------------------------
>>
>> drivers/infiniband/ulp/srp/ib_srp.c |   94 ++++++++++++++++++++++++++++++++++-
>>  drivers/infiniband/ulp/srp/ib_srp.h |    3 +
>>  2 files changed, 95 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
>> index e44939a..12404d5 100644
>> --- a/drivers/infiniband/ulp/srp/ib_srp.c
>> +++ b/drivers/infiniband/ulp/srp/ib_srp.c
>> @@ -433,6 +433,10 @@ static void srp_remove_work(struct work_struct *work)
>>                return;
>>        }
>>        target->state = SRP_TARGET_REMOVED;
>> +
>> +       if (timer_pending(&target->qp_err_timer))
>> +               del_timer_sync(&target->qp_err_timer);
>> +
>>        spin_unlock_irq(target->scsi_host->host_lock);
>>
>>        spin_lock(&target->srp_host->target_lock);
>>
>> [ ... ]
>>     
>
> Calling del_timer_sync() while holding a spinlock can cause locking
> inversion. Has this code been tested on a kernel with LOCKDEP enabled
> ?
>
> Bart.
>   
I have not tested with LOCKDEP enabled., probably del_timer() would be 
sufficient inside target_lock
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html