From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olivier Matz Subject: Re: [PATCH 1/2] drivers/mempool: add stack mempool handler as driver Date: Wed, 29 Mar 2017 10:18:38 +0200 Message-ID: <20170329101838.58162bf7@platinum> References: <1490004190-16892-1-git-send-email-shreyansh.jain@nxp.com> <20170324172227.5bdfac8c@platinum> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: , , To: Shreyansh Jain Return-path: Received: from mail-wm0-f48.google.com (mail-wm0-f48.google.com [74.125.82.48]) by dpdk.org (Postfix) with ESMTP id 7E3B1567C for ; Wed, 29 Mar 2017 10:18:41 +0200 (CEST) Received: by mail-wm0-f48.google.com with SMTP id o81so16347216wmb.1 for ; Wed, 29 Mar 2017 01:18:41 -0700 (PDT) In-Reply-To: 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 Tue, 28 Mar 2017 17:12:47 +0530, Shreyansh Jain wrote: > Hello Olivier, > > On Friday 24 March 2017 09:52 PM, Olivier Matz wrote: > [..] > > > I tried to pass the mempool autotest, and it issues a segfault. > > I think the libraries are missing in rte.app.mk, so no handler is > > registered. > > I have been trying to simulate the segfault that you are referring to > above. But, I think it should not be the case. If a mempool handler is > not registered (as librte_mempool_ring was not included in > mk/rte.app.mk, so, no "ring_mp_mc"), the caller would get error. > > The mempool_autotest is reporting: > > --->8-- > RTE>>mempool_autotest > cannot allocate mp_nocache mempool > Test Failed > --->8-- Here are the reproduction steps: git clone http://dpdk.org/git/dpdk cd dpdk/ wget -O - http://dpdk.org/dev/patchwork/patch/21986/mbox | git am - wget -O - http://dpdk.org/dev/patchwork/patch/21985/mbox | git am - make config T=x86_64-native-linuxapp-gcc make -j32 test-build echo 128 > /sys/devices/system/node/node0/hugepages/hugepages-2048kB/nr_hugepages mkdir -p /mnt/huge mount -t hugetlbfs none /mnt/huge echo mempool_autotest | ./build/app/test -- # segfault # replay with debug make -j32 test-build make -j32 EXTRA_CFLAGS="-O0 -g" test-build ulimit -c unlimited echo mempool_autotest | ./build/app/test -- # segfault + core dump gdb -c core ./build/app/test (gdb) bt #1 0x000000000064dead in rte_mempool_ops_alloc (mp=0x7f8816abdb40) at /root/dpdk/lib/librte_mempool/rte_mempool_ops.c:101 #2 0x000000000064c1e7 in rte_mempool_populate_phys (mp=0x7f8816abdb40, vaddr=0x7f880987a800 , paddr=6958852096, len=26761152, free_cb=0x64c032 , opaque=0x7f8822334d4c) at /root/dpdk/lib/librte_mempool/rte_mempool.c:359 #3 0x000000000064c9db in rte_mempool_populate_default (mp=0x7f8816abdb40) at /root/dpdk/lib/librte_mempool/rte_mempool.c:572 #4 0x000000000064d3d4 in rte_mempool_create (name=0x9b1ff0 "test_nocache", n=12671, elt_size=2048, cache_size=0, private_data_size=0, mp_init=0x0, mp_init_arg=0x0, obj_init=0x49f309 , obj_init_arg=0x0, socket_id=-1, flags=0) at /root/dpdk/lib/librte_mempool/rte_mempool.c:895 #5 0x00000000004a20ed in test_mempool () at /root/dpdk/test/test/test_mempool.c:519 #6 0x0000000000435189 in cmd_autotest_parsed (parsed_result=0x7ffe55006420, cl=0x7c87090, data=0x0) at /root/dpdk/test/test/commands.c:103 #7 0x00000000006749df in cmdline_parse (cl=0x7c87090, buf=0x7c870d8 "mempool_autotest\n") at /root/dpdk/lib/librte_cmdline/cmdline_parse.c:359 (gdb) up #1 0x000000000064dead in rte_mempool_ops_alloc (mp=0x7f8816abdb40) at /root/dpdk/lib/librte_mempool/rte_mempool_ops.c:101 101 return ops->alloc(mp); (gdb) print ops $1 = (struct rte_mempool_ops *) 0x4e69c00 (gdb) print *ops $2 = {name = '\000' , alloc = 0x0, free = 0x0, enqueue = 0x0, dequeue = 0x0, get_count = 0x0} Regards, Olivier > > > > > Adding the following code in lib/librte_mempool/rte_mempool_ops.c > > fixes the crash. > > > > ops = rte_mempool_get_ops(mp->ops_index); > > + if (ops == NULL || ops->alloc == NULL) > > + return -ENOTSUP; > > return ops->alloc(mp); > > Can you tell me for which case did your code reach > rte_mempool_ops_alloc() and segfault? > > In my case, librte_mempool_ring and librte_mempool_stack are not added > to mk/rte.app.mk and it is static compilation. > > > > > Now that drivers are not linked to the mempool library, it can > > happen that there is no handler. Could you please add this patch in your > > patchset? > > Yes, once I can get this issue reproduced. Because I think there is one > more place similar code should go (rte_mempool_ops_getcount). > As per what I can see, this would only happen if rte_mempool_xmem_create > is called and then directly alloc is called. That is not happening for > mempool_autotest. > > - > Shreyansh >