From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 1DBE7A04B5; Mon, 2 Dec 2019 11:43:58 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 5CAC11BF88; Mon, 2 Dec 2019 11:43:57 +0100 (CET) Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by dpdk.org (Postfix) with ESMTP id 9E5E7A3 for ; Mon, 2 Dec 2019 11:43:55 +0100 (CET) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Dec 2019 02:43:54 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,268,1571727600"; d="scan'208";a="360763798" Received: from aburakov-mobl1.ger.corp.intel.com (HELO [10.237.220.92]) ([10.237.220.92]) by orsmga004.jf.intel.com with ESMTP; 02 Dec 2019 02:43:52 -0800 To: Yasufumi Ogawa , David Marchand Cc: "Ananyev, Konstantin" , dev , Yasufumi Ogawa References: <20190724082031.45546-1-yasufum.o@gmail.com> <20191113214346.33749-1-yasufum.o@gmail.com> <20191113214346.33749-2-yasufum.o@gmail.com> <6a6d7228-f22b-9ba5-c288-1701b738b7c4@intel.com> <61dd1730-3c80-da57-126d-84596b23ff31@gmail.com> <4144a7d7-f6af-8ebf-e572-d907e1975837@gmail.com> From: "Burakov, Anatoly" Message-ID: Date: Mon, 2 Dec 2019 10:43:51 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: <4144a7d7-f6af-8ebf-e572-d907e1975837@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH v7 1/1] fbarray: fix duplicated fbarray file in secondary X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 29-Nov-19 5:44 AM, Yasufumi Ogawa wrote: > Hi Anatoly, > > On 2019/11/27 19:26, Burakov, Anatoly wrote: >> On 26-Nov-19 7:40 PM, Yasufumi Ogawa wrote: >>> Hi David, >>> >>> Sorry for slow reply. >>> >>> On 2019/11/14 21:27, David Marchand wrote: >>>> On Thu, Nov 14, 2019 at 12:42 PM Yasufumi Ogawa >>>> wrote: >>>>> >>>>> On 2019/11/14 2:01, Burakov, Anatoly wrote: >>>>>> On 13-Nov-19 9:43 PM, yasufum.o@gmail.com wrote: >>>>>>> From: Yasufumi Ogawa >>>>>>> >>>>>>> In secondary_msl_create_walk(), it creates a file for fbarrays >>>>>>> with its >>>>>>> PID for reserving unique name among secondary processes. However, it >>>>>>> does not work if several secondaries run as app containers >>>>>>> because each >>>>>>> of containerized secondary has PID 1, and failed to reserve >>>>>>> unique name >>>>>>> other than first one. To reserve unique name in each of >>>>>>> containers, use >>>>>>> hostname in addition to PID. >>>>>>> >>>>>>> Cc: stable@dpdk.org >>>>>>> >>>>>>> Signed-off-by: Yasufumi Ogawa >>>>>>> --- >>>>>>>    lib/librte_eal/linux/eal/eal_memalloc.c | 16 +++++++++++++--- >>>>>>>    1 file changed, 13 insertions(+), 3 deletions(-) >>>>>>> >>>>>>> diff --git a/lib/librte_eal/linux/eal/eal_memalloc.c >>>>>>> b/lib/librte_eal/linux/eal/eal_memalloc.c >>>>>>> index af6d0d023..11de6d4d6 100644 >>>>>>> --- a/lib/librte_eal/linux/eal/eal_memalloc.c >>>>>>> +++ b/lib/librte_eal/linux/eal/eal_memalloc.c >>>>>>> @@ -1365,6 +1365,12 @@ secondary_msl_create_walk(const struct >>>>>>> rte_memseg_list *msl, >>>>>>>        struct rte_memseg_list *primary_msl, *local_msl; >>>>>>>        char name[PATH_MAX]; >>>>>>>        int msl_idx, ret; >>>>>>> +    char hostname[HOST_NAME_MAX+1] = { 0 }; >>>>>>> +    /* filename of secondary's fbarray is defined such as >>>>>>> +     * "fbarray_memseg-1048576k-0-0_PID_HOSTNAME" and length of PID >>>>>>> +     * can be 7 digits maximumly. >>>>>>> +     */ >>>>>>> +    int fbarray_sec_name_len = 32 + 7 + 1 + HOST_NAME_MAX + 1; >>>>>> >>>>>> What does 32 stand for? Maybe #define both 32 and 7 values? >>>>> Hi Anatoly, >>>>> >>>>> Thank you for your comments! If my understanding is correct, the >>>>> prefix >>>>> "fbarray_memseg-1048576k-0-0_" is 28 digits and it could be larger if >>>>> using the size of hugepage or the number of NUMA nodes are larger >>>>> possibly. However, I think 32 digits is still enough. >>>>> >>>>>   > Maybe #define both 32 and 7 values? >>>>> Yes. I think it should be better to use #define if this values are >>>>> referred several times. >>>> >>>> >>>> We can truncate to RTE_FBARRAY_NAME_LEN in all cases. >>>> And iiuc, rte_fbarray_init will refuse any longer name anyway. >>> Could I confirm the issue? I've understood that it is failed to >>> validate the name of fbarray in fully_validate() at >>> "lib/librte_eal/common/eal_common_fbarray.c:697". >>> >>> static int >>> fully_validate(const char *name, unsigned int elt_sz, unsigned int len) >>> { >>>          if (name == NULL || elt_sz == 0 || len == 0 || len > INT_MAX) { >>>                  rte_errno = EINVAL; >>>                  return -1; >>>          } >>> >>>          if (strnlen(name, RTE_FBARRAY_NAME_LEN) == >>> RTE_FBARRAY_NAME_LEN) { >>>                  rte_errno = ENAMETOOLONG; >>>                  return -1; >>>          } >>>          return 0; >>> } >>> >>> I should overwrite the definition of RTE_FBARRAY_NAME_LEN as previous >>> patch in this case, and it causes an ABI breakage, right? If so, I >>> would like to make the change and give up to update stable release. >>> >>> Thanks, >>> Yasufumi >>> >> >> It seems we're getting into bikeshedding... >> >> We can do this without ABI breakage. You could have just used >> RTE_FBARRAY_NAME_LEN as max fbarray name length for >> fbarray_sec_name_len (i.e. that would include hostname + pid + >> whatever else there is). The name, as David has pointed out, would be >> truncated to RTE_FBARRAY_NAME_LEN anyway (or, more precisely, it will >> be refused if it's longer than that), so this is the most you can have >> - so you can just use that as the maximum. > I sent v8 patch to change the size of RTE_FBARRAY_NAME_LEN itself to be > allowed the size of secondary's fbarray over 64 bytes. I appreciate if > you agree that. > Why not just limit the name to RTE_FBARRAY_NAME_LEN instead of changing the definition of RTE_FBARRAY_NAME_LEN? One the other hand, technically, fbarray API is experimental. The only structure that uses rte_fbarray is rte_memseg_list, but API's using either rte_fbarray or rte_memseg_list are either internal (memory/VFIO subsystem), or are marked as experimental (walk functions). So i *think* we're actually OK with changing the length of RTE_FBARRAY_NAME_LEN as far as ABI policy goes: nothing in the stable ABI gets affected. David, thoughts? (i think it's probably time to make experimental memory/fbarray stuff stable, but that's a different conversation...) > Thanks, > Yasufumi > -- Thanks, Anatoly