From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH] eal: fix threads block on barrier
Date: Fri, 27 Apr 2018 18:42:34 +0200
Message-ID: <3088214.nrioSNccma@xps>
References: <1524847302-88110-1-git-send-email-jianfeng.tan@intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7Bit
Cc: dev@dpdk.org, Olivier Matz <olivier.matz@6wind.com>,
 Anatoly Burakov <anatoly.burakov@intel.com>, shreyansh.jain@nxp.com
To: Jianfeng Tan <jianfeng.tan@intel.com>
Return-path: <dev-bounces@dpdk.org>
Received: from out2-smtp.messagingengine.com (out2-smtp.messagingengine.com
 [66.111.4.26]) by dpdk.org (Postfix) with ESMTP id 8676ACF68
 for <dev@dpdk.org>; Fri, 27 Apr 2018 18:42:37 +0200 (CEST)
In-Reply-To: <1524847302-88110-1-git-send-email-jianfeng.tan@intel.com>
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <https://dpdk.org/ml/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <https://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
Sender: "dev" <dev-bounces@dpdk.org>

27/04/2018 18:41, Jianfeng Tan:
> Below commit introduced pthread barrier for synchronization.
> But two IPC threads block on the barrier, and never wake up.
> 
>   (gdb) bt
>   #0  futex_wait (private=0, expected=0, futex_word=0x7fffffffcff4)
>       at ../sysdeps/unix/sysv/linux/futex-internal.h:61
>   #1  futex_wait_simple (private=0, expected=0, futex_word=0x7fffffffcff4)
>       at ../sysdeps/nptl/futex-internal.h:135
>   #2  __pthread_barrier_wait (barrier=0x7fffffffcff0) at pthread_barrier_wait.c:184
>   #3  rte_thread_init (arg=0x7fffffffcfe0)
>       at ../dpdk/lib/librte_eal/common/eal_common_thread.c:160
>   #4  start_thread (arg=0x7ffff6ecf700) at pthread_create.c:333
>   #5  clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109
> 
> Through analysis, we find the barrier defined on the stack could be the
> root cause. This patch will change to use heap memory as the barrier.
> 
> Fixes: d651ee4919cd ("eal: set affinity for control threads")

Shreyansh (Cc'ed) is seeing some bugs with this patch too.