From: santosh <santosh.shukla@caviumnetworks.com>
To: Jan Blunck <jblunck@infradead.org>,
Olivier Matz <olivier.matz@6wind.com>
Cc: dev <dev@dpdk.org>, Ilya Matveychikov <matvejchikov@gmail.com>,
Adrien Mazarguil <adrien.mazarguil@6wind.com>,
sergio.gonzalez.monroy@intel.com, stable@dpdk.org
Subject: Re: [dpdk-stable] [dpdk-dev] [PATCH] eal: don't advertise a physical address when no hugepages
Date: Mon, 26 Jun 2017 12:41:41 +0530 [thread overview]
Message-ID: <42e53bce-776f-6ede-5565-533f7c2186ed@caviumnetworks.com> (raw)
In-Reply-To: <CALe+Z03HuTQoYTT_W0=B4MBHWy9GWwOATmrtPqog0AxsvsRJvw@mail.gmail.com>
Hi Olivier,
On Friday 23 June 2017 10:38 PM, Jan Blunck wrote:
> On Fri, Jun 23, 2017 at 10:11 AM, Olivier Matz <olivier.matz@6wind.com> wrote:
>> Hi Jan,
>>
>> On Sat, 10 Jun 2017 10:31:22 +0200, Jan Blunck <jblunck@infradead.org> wrote:
>>> On Fri, Jun 9, 2017 at 10:29 AM, Olivier Matz <olivier.matz@6wind.com> wrote:
>>>> When populating a mempool with a virtual memory area, the mempool
>>>> library expects to be able to get the physical address of each page.
>>>>
>>>> When started with --no-huge, the physical addresses may not be available
>>>> because the pages are not locked in memory. It sometimes returns
>>>> RTE_BAD_PHYS_ADDR, which makes the mempool_populate() function to fail.
>>>>
>>>> This was working before the commit cdc242f260e7 ("eal/linux: support
>>>> running as unprivileged user"), because rte_mem_virt2phy() was returning
>>>> 0 instead of RTE_BAD_PHYS_ADDR, which was seen as a valid physical
>>>> address.
>>>>
>>>> Since --no-huge is a debug function that breaks the support of physical
>>>> drivers, always set physical addresses to RTE_BAD_PHYS_ADDR in memzones
>>>> or in rte_mem_virt2phy(), and ensure that mempool won't complain in that
>>>> case.
>>>>
>>>> Fixes: cdc242f260e7 ("eal/linux: support running as unprivileged user")
>>>>
>>>> CC: stable@dpdk.org
>>>> Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
>>>> ---
>>>> lib/librte_eal/common/eal_common_memzone.c | 5 ++++-
>>>> lib/librte_eal/linuxapp/eal/eal_memory.c | 7 +++++++
>>>> lib/librte_mempool/rte_mempool.c | 2 +-
>>>> 3 files changed, 12 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/lib/librte_eal/common/eal_common_memzone.c b/lib/librte_eal/common/eal_common_memzone.c
>>>> index 3026e36b8..c465c8fc2 100644
>>>> --- a/lib/librte_eal/common/eal_common_memzone.c
>>>> +++ b/lib/librte_eal/common/eal_common_memzone.c
>>>> @@ -251,7 +251,10 @@ memzone_reserve_aligned_thread_unsafe(const char *name, size_t len,
>>>>
>>>> mcfg->memzone_cnt++;
>>>> snprintf(mz->name, sizeof(mz->name), "%s", name);
>>>> - mz->phys_addr = rte_malloc_virt2phy(mz_addr);
>>>> + if (rte_eal_has_hugepages())
>>>> + mz->phys_addr = rte_malloc_virt2phy(mz_addr);
>>>> + else
>>>> + mz->phys_addr = RTE_BAD_PHYS_ADDR;
>>> Since you set phys_addrs_available to false rte_malloc_virt2phy()
>>> anyway returns RTE_BAD_PHYS_ADDR so I believe the conditional isn't
>>> necessary here.
>>>
>>> Rest of the patch looks good to me.
>> The variable phys_addrs_available only impacts rte_mem_virt2phy().
>> Here, for memzones allocation, rte_malloc_virt2phy() is used, and
>> it gets its physical address by retrieving it from the memseg structure.
>>
>> With the full patch, "dump_memzone" displays something like:
>> Zone 0: name:<rte_eth_dev_data>, phys:0xffffffffffffffff, len:0x30100, [...]
>> ...
>>
>> If I strip the memzone part, it displays:
>> Zone 0: name:<rte_eth_dev_data>, phys:0x7fe382c62640, len:0x30100, [...]
>> ...
>>
>> So I think we should either keep the patch as is, or change the memseg
>> and malloc part like this (it's maybe better):
>>
>> --- a/lib/librte_eal/common/rte_malloc.c
>> +++ b/lib/librte_eal/common/rte_malloc.c
>> @@ -254,5 +254,7 @@ rte_malloc_virt2phy(const void *addr)
>> const struct malloc_elem *elem = malloc_elem_from_data(addr);
>> if (elem == NULL)
>> return 0;
>> + if (elem->ms->phys_addr == RTE_BAD_PHYS_ADDR)
>> + return RTE_BAD_PHYS_ADDR;
>> return elem->ms->phys_addr + ((uintptr_t)addr - (uintptr_t)elem->ms->addr);
>> }
>> diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c b/lib/librte_eal/linuxapp/eal/eal_memory.c
>> index 1c99852..2a401ca 100644
>> --- a/lib/librte_eal/linuxapp/eal/eal_memory.c
>> +++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
>> @@ -973,7 +973,7 @@ rte_eal_hugepage_init(void)
>> strerror(errno));
>> return -1;
>> }
>> - mcfg->memseg[0].phys_addr = (phys_addr_t)(uintptr_t)addr;
>> + mcfg->memseg[0].phys_addr = RTE_BAD_PHYS_ADDR;
>> mcfg->memseg[0].addr = addr;
>> mcfg->memseg[0].hugepage_sz = RTE_PGSIZE_4K;
>> mcfg->memseg[0].len = internal_config.memory;
>>
>>
>> Let me know what you are ok with this and I'll send a v2.
>>
> This approach looks better to me.
>
> hanks,
> Jan
Approach LGTM, though small comment:
I think we also need to fix error return description for API rte_malloc_virt2phy.
It says 'NULL' on error. It should be 0 or RTE_BAD_PHYS_ADDR.
In fact, we should remove '0' as error return and keep RTE_BAD_PHYS_ADDR as the error value.
If so then change may look like:
if (elem == NULL || elem->ms->phys_addr == RTE_BAD_PHYS_ADDR)
return RTE_BAD_PHYS_ADDR;
Provided that return value '0' considered as error value in current code.
Having said that, few drivers using rte_malloc_virt2phy without an error check.
I guess now they must check return value before using phys_addr_t.
next prev parent reply other threads:[~2017-06-26 7:11 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20170609102727.0eb7f39d@platinum>
2017-06-09 8:29 ` [dpdk-stable] " Olivier Matz
2017-06-10 8:31 ` Jan Blunck
2017-06-23 8:11 ` Olivier Matz
2017-06-23 17:08 ` Jan Blunck
2017-06-26 7:11 ` santosh [this message]
2017-06-12 13:58 ` Adrien Mazarguil
2017-07-03 10:04 ` [dpdk-stable] [PATCH v2] " Olivier Matz
2017-07-03 10:17 ` Jan Blunck
2017-07-04 15:53 ` Thomas Monjalon
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=42e53bce-776f-6ede-5565-533f7c2186ed@caviumnetworks.com \
--to=santosh.shukla@caviumnetworks.com \
--cc=adrien.mazarguil@6wind.com \
--cc=dev@dpdk.org \
--cc=jblunck@infradead.org \
--cc=matvejchikov@gmail.com \
--cc=olivier.matz@6wind.com \
--cc=sergio.gonzalez.monroy@intel.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).