----- Original Message ----- > From: "Leon Romanovsky" <leon@xxxxxxxxxx> > To: "Bart Van Assche" <bart.vanassche@xxxxxxxxxxx> > Cc: "Laurence Oberman" <loberman@xxxxxxxxxx>, "Yishai Hadas" <yishaih@xxxxxxxxxxxx>, linux-rdma@xxxxxxxxxxxxxxx > Sent: Tuesday, June 14, 2016 9:15:52 AM > Subject: Re: multipath IB/srp fail-over testing lands up in dump stack in swiotlb_alloc_coherent() > > On Tue, Jun 14, 2016 at 02:25:15PM +0200, Bart Van Assche wrote: > > On 06/14/2016 02:08 PM, Leon Romanovsky wrote: > > >On Tue, Jun 14, 2016 at 11:24:28AM +0200, Bart Van Assche wrote: > > >>On 06/14/2016 03:56 AM, Laurence Oberman wrote: > > >>>Tracing [ ... ] > > >> > > >>Can you try to set the kernel command line parameter swiotlb to a value > > >>that > > >>is a multiple of its default (64MB), reboot and see whether that helps? > > >>See > > >>also Documentation/kernel-parameters.txt in the kernel tree. > > > > > >Do you think that 64MB is not enough for this scenario? > > > > Hello Leon, > > > > Does this mean that you think that the "swiotlb buffer is full" messages > > reported by Laurence could be caused by something else than hitting the > > swiotlb limit? > > I don't have enough knowledge in that area to answer if message "swiotlb > buffer is full" is correctly explain current situation and I will be > glad to get input from you about it. > > Thanks. > > > > > Bart. > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > Hello Bart and Leon Set to swiotlb=4, I no longer have the swiotlb issue. Its no longer taking the error path so I confirm that increasing the swiotlb slab count solves this issue. BOOT_IMAGE=/vmlinuz-4.7.0-rc1.bart.swiotlb+ root=/dev/mapper/rhel-root ro crashkernel=auto rd.lvm.lv=rhel/root rd.lvm.lv=rhel/swap console=ttyS1,115200n8 scsi_mod.use_blk_mq=1 swiotlb=4 I am in the process of preparing a Doc patch for IB/srp and IB/srpt where I have captured all the tuning work I have done with Bart. I will add this to the Doc patch priot to sending it. Many Thanks Laurence -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
