From: "Burakov, Anatoly" <anatoly.burakov@intel.com>
To: Eelco Chaudron <echaudro@redhat.com>,
Alejandro Lucero <alejandro.lucero@netronome.com>
Cc: dev <dev@dpdk.org>,
stable@dpdk.org, Maxime Coquelin <maxime.coquelin@redhat.com>,
Ferruh Yigit <ferruh.yigit@intel.com>
Subject: Re: [dpdk-stable] [PATCH v3 1/6] mem: add function for checking memsegs IOVAs addresses
Date: Tue, 10 Jul 2018 12:33:45 +0100 [thread overview]
Message-ID: <33c605a8-cf16-b2f2-ce1d-cdc5d85bb155@intel.com> (raw)
In-Reply-To: <24D4D56B-BE3A-43DC-AEEE-A063A11C73EC@redhat.com>
On 10-Jul-18 12:14 PM, Eelco Chaudron wrote:
>
>
> On 10 Jul 2018, at 12:52, Alejandro Lucero wrote:
>
>> On Tue, Jul 10, 2018 at 11:06 AM, Eelco Chaudron <echaudro@redhat.com>
>> wrote:
>>
>>>
>>>
>>> On 10 Jul 2018, at 11:34, Alejandro Lucero wrote:
>>>
>>> On Tue, Jul 10, 2018 at 9:56 AM, Eelco Chaudron <echaudro@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.lucero@netronome.com>
>>>>>> Acked-by: Anatoly Burakov <anatoly.burakov@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.
Pre-18.05, all memsegs are allocated continuously. Memseg lists and
memseg list walk functions are 18.05+.
Alejandro, perhaps it would be worth it to tag your patchset with
"pre-18.05" to avoid similar confusion in the future?
--
Thanks,
Anatoly
next prev parent reply other threads:[~2018-07-10 11:33 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-04 12:53 [dpdk-stable] [PATCH v3 0/6] use IOVAs check based on DMA mask Alejandro Lucero
2018-07-04 12:53 ` [dpdk-stable] [PATCH v3 1/6] mem: add function for checking memsegs IOVAs addresses Alejandro Lucero
2018-07-10 8:56 ` Eelco Chaudron
2018-07-10 9:34 ` Alejandro Lucero
2018-07-10 10:06 ` Eelco Chaudron
2018-07-10 10:52 ` Alejandro Lucero
2018-07-10 11:14 ` Eelco Chaudron
2018-07-10 11:33 ` Burakov, Anatoly [this message]
2018-07-10 11:43 ` Alejandro Lucero
2018-07-10 11:55 ` Eelco Chaudron
2018-07-10 11:40 ` Alejandro Lucero
2018-07-04 12:53 ` [dpdk-stable] [PATCH v3 2/6] ethdev: add function for checking IOVAs by a device Alejandro Lucero
2018-07-07 17:30 ` [dpdk-stable] [dpdk-dev] " Andrew Rybchenko
2018-07-10 8:57 ` [dpdk-stable] " Eelco Chaudron
2018-07-10 9:42 ` Alejandro Lucero
2018-07-10 9:44 ` Alejandro Lucero
2018-07-04 12:53 ` [dpdk-stable] [PATCH v3 3/6] bus/pci: use IOVAs check when setting IOVA mode Alejandro Lucero
2018-07-10 10:14 ` Eelco Chaudron
2018-07-10 15:37 ` Alejandro Lucero
2018-07-04 12:53 ` [dpdk-stable] [PATCH v3 4/6] mem: use address hint for mapping hugepages Alejandro Lucero
2018-07-10 11:15 ` Eelco Chaudron
2018-07-04 12:53 ` [dpdk-stable] [PATCH v3 5/6] net/nfp: check hugepages IOVAs based on DMA mask Alejandro Lucero
2018-07-10 10:17 ` Eelco Chaudron
2018-07-04 12:53 ` [dpdk-stable] [PATCH v3 6/6] net/nfp: support IOVA VA mode Alejandro Lucero
2018-07-10 10:18 ` Eelco Chaudron
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=33c605a8-cf16-b2f2-ce1d-cdc5d85bb155@intel.com \
--to=anatoly.burakov@intel.com \
--cc=alejandro.lucero@netronome.com \
--cc=dev@dpdk.org \
--cc=echaudro@redhat.com \
--cc=ferruh.yigit@intel.com \
--cc=maxime.coquelin@redhat.com \
--cc=stable@dpdk.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).