On Tue, Jul 10, 2018 at 12:14 PM, Eelco Chaudron <echau...@redhat.com>
wrote:
>
>
> On 10 Jul 2018, at 12:52, Alejandro Lucero wrote:
>
> On Tue, Jul 10, 2018 at 11:06 AM, Eelco Chaudron <echau...@redhat.com>
>> wrote:
>>
>>
>>>
>>> On 10 Jul 2018, at 11:34, Alejandro Lucero wrote:
>>>
>>> On Tue, Jul 10, 2018 at 9:56 AM, Eelco Chaudron <echau...@redhat.com>
>>>
>>>> wrote:
>>>>
>>>>
>>>>
>>>>> On 4 Jul 2018, at 14:53, Alejandro Lucero wrote:
>>>>>
>>>>> A device can suffer addressing limitations. This functions checks
>>>>>
>>>>> memsegs have iovas within the supported range based on dma mask.
>>>>>>
>>>>>> PMD should use this during initialization if supported devices
>>>>>> suffer addressing limitations, returning an error if this function
>>>>>> returns memsegs out of range.
>>>>>>
>>>>>> Another potential usage is for emulated IOMMU hardware with addressing
>>>>>> limitations.
>>>>>>
>>>>>> Signed-off-by: Alejandro Lucero <alejandro.luc...@netronome.com>
>>>>>> Acked-by: Anatoly Burakov <anatoly.bura...@intel.com>
>>>>>> ---
>>>>>> lib/librte_eal/common/eal_common_memory.c | 33
>>>>>> ++++++++++++++++++++++++++++++
>>>>>> lib/librte_eal/common/include/rte_memory.h | 3 +++
>>>>>> lib/librte_eal/rte_eal_version.map | 1 +
>>>>>> 3 files changed, 37 insertions(+)
>>>>>>
>>>>>> diff --git a/lib/librte_eal/common/eal_common_memory.c
>>>>>> b/lib/librte_eal/common/eal_common_memory.c
>>>>>> index fc6c44d..f5efebe 100644
>>>>>> --- a/lib/librte_eal/common/eal_common_memory.c
>>>>>> +++ b/lib/librte_eal/common/eal_common_memory.c
>>>>>> @@ -109,6 +109,39 @@
>>>>>> }
>>>>>> }
>>>>>>
>>>>>> +/* check memseg iovas are within the required range based on dma mask
>>>>>> */
>>>>>> +int
>>>>>> +rte_eal_check_dma_mask(uint8_t maskbits)
>>>>>> +{
>>>>>> +
>>>>>> + const struct rte_mem_config *mcfg;
>>>>>> + uint64_t mask;
>>>>>> + int i;
>>>>>> +
>>>>>>
>>>>>>
>>>>>> I think we should add some sanity check to the input maskbits, i.e.
>>>>> [64,0)
>>>>> or [64, 32]? What would be a reasonable lower bound.
>>>>>
>>>>>
>>>>> This is not a user's API, so any invocation will be reviewed, but I
>>>>> guess
>>>>>
>>>> adding a sanity check here does not harm.
>>>>
>>>> Not sure about lower bound but upper should 64, although it does not
>>>> make
>>>> sense but it is safe. Lower bound is not so problematic.
>>>>
>>>>
>>>>
>>>> + /* create dma mask */
>>>>>
>>>>> + mask = ~((1ULL << maskbits) - 1);
>>>>>> +
>>>>>> + /* get pointer to global configuration */
>>>>>> + mcfg = rte_eal_get_configuration()->mem_config;
>>>>>> +
>>>>>> + for (i = 0; i < RTE_MAX_MEMSEG; i++) {
>>>>>> + if (mcfg->memseg[i].addr == NULL)
>>>>>> + break;
>>>>>>
>>>>>>
>>>>> Looking at some other code, it looks like NULL entries might exists. So
>>> should a continue; rather than a break; be used here?
>>>
>>>
>>> I do not think so. memsegs are allocated sequentially, so first with addr
>> as NULL implies no more memsegs.
>>
>
> I was referring to the mem walk functions, rte_memseg_list_walk(). Maybe
> some having more experience with this area can review/comment.
>
>
This patchset applies to 17.11.3 which has not that function implemented.
You can see what rte_eal_get_physmem_size and rte_dump_physmem_layout do in
lib/librte_eal/common/eal_common_memory.c file regarding memseg "walks"
when addr is NULL.
>
>
>>
>>
>>> +
>>>
>>>> + if (mcfg->memseg[i].iova & mask) {
>>>>>> + RTE_LOG(INFO, EAL,
>>>>>> + "memseg[%d] iova %"PRIx64" out of
>>>>>> range:\n",
>>>>>> + i, mcfg->memseg[i].iova);
>>>>>> +
>>>>>> + RTE_LOG(INFO, EAL, "\tusing dma mask
>>>>>> %"PRIx64"\n",
>>>>>> + mask);
>>>>>> + return -1;
>>>>>> + }
>>>>>> + }
>>>>>> +
>>>>>> + return 0;
>>>>>> +}
>>>>>> +
>>>>>> /* return the number of memory channels */
>>>>>> unsigned rte_memory_get_nchannel(void)
>>>>>> {
>>>>>> diff --git a/lib/librte_eal/common/include/rte_memory.h
>>>>>> b/lib/librte_eal/common/include/rte_memory.h
>>>>>> index 80a8fc0..b2a0168 100644
>>>>>> --- a/lib/librte_eal/common/include/rte_memory.h
>>>>>> +++ b/lib/librte_eal/common/include/rte_memory.h
>>>>>> @@ -209,6 +209,9 @@ struct rte_memseg {
>>>>>> */
>>>>>> unsigned rte_memory_get_nrank(void);
>>>>>>
>>>>>> +/* check memsegs iovas are within a range based on dma mask */
>>>>>> +int rte_eal_check_dma_mask(uint8_t maskbits);
>>>>>> +
>>>>>> /**
>>>>>> * Drivers based on uio will not load unless physical
>>>>>> * addresses are obtainable. It is only possible to get
>>>>>> diff --git a/lib/librte_eal/rte_eal_version.map
>>>>>> b/lib/librte_eal/rte_eal_version.map
>>>>>> index f4f46c1..aa6cf87 100644
>>>>>> --- a/lib/librte_eal/rte_eal_version.map
>>>>>> +++ b/lib/librte_eal/rte_eal_version.map
>>>>>> @@ -184,6 +184,7 @@ DPDK_17.11 {
>>>>>>
>>>>>> rte_eal_create_uio_dev;
>>>>>> rte_bus_get_iommu_class;
>>>>>> + rte_eal_check_dma_mask;
>>>>>> rte_eal_has_pci;
>>>>>> rte_eal_iova_mode;
>>>>>> rte_eal_mbuf_default_mempool_ops;
>>>>>> --
>>>>>> 1.9.1
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>
>>>
>
>
