Hi Michael, Acked-by: Wenzhuo Lu <wenzhuo.lu at intel.com>
> -----Original Message----- > From: Qiu, Michael > Sent: Tuesday, February 2, 2016 10:07 AM > To: Lu, Wenzhuo; dev at dpdk.org > Cc: Zhou, Danny; Liu, Yong; Liang, Cunming; Zhang, Helin > Subject: Re: [PATCH v2] ixgbe: Fix disable interrupt twice > > [+cc helin] > > On 2/2/2016 9:03 AM, Lu, Wenzhuo wrote: > > Hi Michael, > > > >> -----Original Message----- > >> From: Qiu, Michael > >> Sent: Monday, February 1, 2016 4:05 PM > >> To: Lu, Wenzhuo; dev at dpdk.org > >> Cc: Zhou, Danny; Liu, Yong; Liang, Cunming > >> Subject: Re: [PATCH v2] ixgbe: Fix disable interrupt twice > >> > >> On 1/29/2016 4:07 PM, Lu, Wenzhuo wrote: > >>> Hi Michael, > >>> > >>>> -----Original Message----- > >>>> From: Qiu, Michael > >>>> Sent: Friday, January 29, 2016 1:58 PM > >>>> To: dev at dpdk.org > >>>> Cc: Zhou, Danny; Liu, Yong; Liang, Cunming; Lu, Wenzhuo; Qiu, > >>>> Michael > >>>> Subject: [PATCH v2] ixgbe: Fix disable interrupt twice > >>>> > >>>> Currently, ixgbe vf and pf will disable interrupt twice in stop > >>>> stage and uninit stage. It will cause an error: > >>>> > >>>> testpmd> quit > >>>> > >>>> Shutting down port 0... > >>>> Stopping ports... > >>>> Done > >>>> Closing ports... > >>>> EAL: Error disabling MSI-X interrupts for fd 26 > >>>> Done > >>>> > >>>> Becasue the interrupt already been disabled in stop stage. > >>>> Since it is enabled in init stage, better remove from stop stage. > >>> I'm afraid it's not a good idea to just remove the intr_disable from > >>> dev_stop. > >>> I think dev_stop have the chance to be used independently with > >>> dev_unint. In > >> this scenario, we still need intr_disable, right? > >>> Maybe what we need is some check before we disable the intr:) > >> Yes, indeed we need some check in disable intr, but it need > >> additional fields in "struct rte_intr_handle", and it's much saft to > >> do so, but as I check i40e/fm10k code, only ixgbe disable it in dev_stop(). > > I found fm10k doesn't enable intr in dev_start. So, I think it's OK. But > > i40e > enables intr in dev_start. > > To my opinion, it's more like i40e misses the intr_disable in dev_stop. > > I don't think i40e miss it, because it not the right please to disable > interrupt. > because all interrupts are enabled in init stage. > > Actually, ixgbe enable the interrupt in init stage, but in dev_start, it > disable it first > and re-enable, so it just the same with doing nothing about interrupt. > > Just think below: > > 1. start the port.(interrupt already enabled in init stage, disable --> > re-enable) > 2. stop the port.(disable interrupt) > 3. start port again(Try to disable, but failed, already disabled) > > Would you think the code has issue? Got your point. So, dev_start/stop will not influence the state of intr enabling/disabling. The intr will be enabled/disabled during dev_init/unint. Thanks. > > Thanks, > Michael > > > Maybe we can follow fm10k's style. > > > >> On other hand, if we remove it in dev_stop, any side effect? In ixgbe > >> start, it will always disable it first and then re-enable it, so it's safe. > > I think you mean we can disable intr anyway even if it has been disabled. > > Actually, we couldn't, DPDK call VFIO ioctl to kernel to disable interrupts, > and if > we try disable twice, it will return and error. > That's why I mean we need a flag to show the interrupts stats. If it already > disabled, we do not need call in to kernel. just return and give a warning > message. > > Thanks, > Michael > > > Sounds more like why we don't > > need this patch :) > > > >> Thanks, > >> Michael > >
