[dpdk-dev] [PATCH v2 0/7] fix DMA mask check
Thomas Monjalon
thomas at monjalon.net
Mon Nov 5 01:03:14 CET 2018
02/11/2018 19:38, Ferruh Yigit:
> On 11/1/2018 7:53 PM, Alejandro Lucero wrote:
> > A patchset sent introducing DMA mask checks has several critical
> > issues precluding apps to execute. The patchset was reviewed and
> > finally accepted after three versions. Obviously it did not go
> > through the proper testing what can be explained, at least from my
> > side, due to the big changes to the memory initialization code these
> > last months. It turns out the patchset did work with legacy memory
> > and I'm afraid that was mainly my testing.
> >
> > This patchset should solve the main problems reported:
> >
> > - deadlock duriing initialization
> > - segmentation fault with secondary processes
> >
> > For solving the deadlock, a new API is introduced:
> >
> > rte_mem_check_dma_mask_safe/unsafe
> >
> > making the previous rte_mem_check_dma_mask the one those new functions
> > end calling. A boolean param is used for calling rte_memseg_walk thread
> > safe or thread unsafe. This second option is needed for avoiding the
> > deadlock.
> >
> > For the secondary processes problem, the call to check the dma mask is
> > avoided from code being executed before the memory initialization.
> > Instead, a new API function, rte_mem_set_dma_mask is introduced, which
> > will be used in those cases. The dma mask check is done once the memory
> > initialization is completed.
> >
> > This last change implies the IOVA mode can not be set depending on IOMMU
> > hardware limitations, and it is assumed IOVA VA is possible. If the dma
> > mask check reports a problem after memory initilization, the error
> > message includes now advice for trying with --iova-mode option set to
> > pa.
> >
> > The patchet also includes the dma mask check for legacy memory and the
> > no hugepage option.
> >
> > Finally, all the DMA mask API has been updated for using the same prefix
> > than other EAL memory code.
> >
> > An initial version of this patchset has been tested by Intel DPDK
> > Validation team and it seems it solves all the problems reported. This
> > final patchset has the same functionality with minor changes. I have
> > successfully tested the patchset with my limited testbench.
> >
> > v2:
> > - modify error messages with more descriptive information
> > - change safe/unsafe versions for dma check to previous one plus a
> > thread_unsafe version.
> > - use rte_eal_using_phys_addr instead of getuid
> > - fix comments
> > - reorder patches
> >
> > Alejandro Lucero (7):
> > mem: fix call to DMA mask check
> > mem: use proper prefix
> > mem: add function for setting DMA mask
> > bus/pci: avoid call to DMA mask check
> > mem: modify error message for DMA mask check
> > eal/mem: use DMA mask check for legacy memory
> > mem: add thread unsafe version for checking DMA mask
>
> Tested-by: Ferruh Yigit <ferruh.yigit at intel.com>
>
> Fixing the deadlock issue, and build/per-patch build is good.
Applied, thanks
More information about the dev
mailing list