On Wed, Jun 25, 2014 at 05:50:08PM +1000, Alexey Kardashevskiy wrote: >On 06/25/2014 03:27 PM, Wei Yang wrote: >> On Wed, Jun 25, 2014 at 02:12:34PM +1000, Alexey Kardashevskiy wrote: >>> On 06/25/2014 11:12 AM, Wei Yang wrote: >>>> On Tue, Jun 24, 2014 at 08:06:32PM +1000, Alexey Kardashevskiy wrote: >>>>> On 06/10/2014 11:56 AM, Wei Yang wrote: >>>>>> Current iommu_table of a PE is a static field. This will have a problem when >>>>>> iommu_free_table is called. >>>>> >>>>> What kind of problem? This table is per PE and PE is not going anywhere. >>>>> >>>> >>>> Yes, for Bus PE, they will always sit in the system. When VF PE introduced, >>>> they could be released on the fly. When they are released, so do the iommu >>>> table for the PE. >>> >>> iommu_table is a part of PE struct. When PE is released, iommu_table will >>> go with it as well. Why to make is a pointer? I would understand it if you >>> added reference counting there but no - iommu_table's lifetime is equal to >>> PE lifetime. >>> >> >> Yes, iommu_talbe's life time equals to PE lifetime, so when releasing a PE we >> need to release the iommu table. Currently, there is one function to release >> the iommu table, iommu_free_table() which takes a pointer of the iommu_table >> and release it. >> >> If the iommu table in PE is just a part of PE, it will have some problem to >> release it with iommu_free_table(). That's why I make it a pointer in PE >> structure. > >So you are saying that you want to release PE by one kfree() and release >iommu_table by another kfree (embedded into iommu_free_table()). For me >that means that PE and iommu_table have different lifetime. > Hmm... it is right, the lifetime of these two may have some difference. >And I cannot find the exact place in this patchset where you call >iommu_free_table(), what do I miss? > This is called in pnv_pci_release_dev_dma(), which is introduced in the commit cd740988: powerpc/powernv: allocate VF PE > > > >-- >Alexey -- Richard Yang Help you, Help me -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
