From mboxrd@z Thu Jan 1 00:00:00 1970
Return-Path: <konstantin.ananyev@intel.com>
Received: from mga14.intel.com (mga14.intel.com [192.55.52.115])
by dpdk.org (Postfix) with ESMTP id 91A3F6CBB
for <dev@dpdk.org>; Tue, 8 May 2018 17:19:27 +0200 (CEST)
X-Amp-Result: SKIPPED(no attachment in message)
X-Amp-File-Uploaded: False
Received: from orsmga006.jf.intel.com ([10.7.209.51])
by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384;
08 May 2018 08:19:26 -0700
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.49,378,1520924400"; d="scan'208";a="40198193"
Received: from irsmsx152.ger.corp.intel.com ([163.33.192.66])
by orsmga006.jf.intel.com with ESMTP; 08 May 2018 08:19:23 -0700
Received: from irsmsx105.ger.corp.intel.com ([169.254.7.214]) by
IRSMSX152.ger.corp.intel.com ([169.254.6.199]) with mapi id 14.03.0319.002;
Tue, 8 May 2018 16:19:23 +0100
From: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>
To: "Guo, Jia" <jia.guo@intel.com>, "stephen@networkplumber.org"
<stephen@networkplumber.org>, "Richardson, Bruce"
<bruce.richardson@intel.com>, "Yigit, Ferruh" <ferruh.yigit@intel.com>,
"gaetan.rivet@6wind.com" <gaetan.rivet@6wind.com>, "Wu, Jingjing"
<jingjing.wu@intel.com>, "thomas@monjalon.net" <thomas@monjalon.net>,
"motih@mellanox.com" <motih@mellanox.com>, "matan@mellanox.com"
<matan@mellanox.com>, "Van Haaren, Harry" <harry.van.haaren@intel.com>,
"Tan, Jianfeng" <jianfeng.tan@intel.com>
CC: "jblunck@infradead.org" <jblunck@infradead.org>, "shreyansh.jain@nxp.com"
<shreyansh.jain@nxp.com>, "dev@dpdk.org" <dev@dpdk.org>, "Zhang, Helin"
<helin.zhang@intel.com>
Thread-Topic: [PATCH V21 2/4] eal: add failure handle mechanism for hot plug
Thread-Index: AQHT4syJCEBEclxmNk6aelBVPgf1/aQfukwAgAYpEoCAABZBsA==
Date: Tue, 8 May 2018 15:19:22 +0000
Message-ID: <2601191342CEEE43887BDE71AB977258AEDC3CE6@irsmsx105.ger.corp.intel.com>
References: <1498711073-42917-1-git-send-email-jia.guo@intel.com>
<1525344524-26946-1-git-send-email-jia.guo@intel.com>
<1525344524-26946-3-git-send-email-jia.guo@intel.com>
<2601191342CEEE43887BDE71AB977258AEDC28C9@irsmsx105.ger.corp.intel.com>
<6419dd13-e038-11bd-0bdc-beef4467bde9@intel.com>
In-Reply-To: <6419dd13-e038-11bd-0bdc-beef4467bde9@intel.com>
Accept-Language: en-IE, en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiMDUxYjA0NzUtMmM2Yi00N2RkLThjMzUtMjUxODRiOWEyZGM0IiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX05UIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE2LjUuOS4zIiwiVHJ1c3RlZExhYmVsSGFzaCI6IjNucHo0UjdLZVwvRGJqNjdxRjU3Tnlmb0V3aFQzWWZOZHJYdFQ0MnBkeWgwPSJ9
x-ctpclassification: CTP_NT
dlp-product: dlpe-windows
dlp-version: 11.0.200.100
dlp-reaction: no-action
x-originating-ip: [163.33.239.180]
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
Subject: Re: [dpdk-dev] [PATCH V21 2/4] eal: add failure handle mechanism
for hot plug
X-BeenThere: dev@dpdk.org
X-Mailman-Version: 2.1.15
Precedence: list
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>
X-List-Received-Date: Tue, 08 May 2018 15:19:28 -0000
> -----Original Message-----
> From: Guo, Jia
> Sent: Tuesday, May 8, 2018 3:57 PM
> To: Ananyev, Konstantin <konstantin.ananyev@intel.com>; stephen@networkpl=
umber.org; Richardson, Bruce
> <bruce.richardson@intel.com>; Yigit, Ferruh <ferruh.yigit@intel.com>; gae=
tan.rivet@6wind.com; Wu, Jingjing
> <jingjing.wu@intel.com>; thomas@monjalon.net; motih@mellanox.com; matan@m=
ellanox.com; Van Haaren, Harry
> <harry.van.haaren@intel.com>; Tan, Jianfeng <jianfeng.tan@intel.com>
> Cc: jblunck@infradead.org; shreyansh.jain@nxp.com; dev@dpdk.org; Zhang, H=
elin <helin.zhang@intel.com>
> Subject: Re: [PATCH V21 2/4] eal: add failure handle mechanism for hot pl=
ug
>=20
>=20
>=20
> On 5/4/2018 11:56 PM, Ananyev, Konstantin wrote:
> > Hi Jeff,
> >
> >> This patch introduces a failure handler mechanism to handle device
> >> hot unplug event. When device be hot plug out, the device resource
> >> become invalid, if this resource is still be unexpected read/write,
> >> system will crash. This patch let eal help application to handle
> >> this fault, when sigbus error occur, check the failure address and
> >> accordingly remap the invalid memory for the corresponding device,
> >> that could guaranty the application not to be shut down when hot plug.
> >>
> >> Signed-off-by: Jeff Guo <jia.guo@intel.com>
> >> ---
> >> v21->v20:
> >> sync failure hanlde to fix multiple process issue
> >> ---
> >> lib/librte_eal/linuxapp/eal/eal_dev.c | 154 ++++++++++++++++++++++++=
+++++++++-
> >> 1 file changed, 153 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/lib/librte_eal/linuxapp/eal/eal_dev.c b/lib/librte_eal/li=
nuxapp/eal/eal_dev.c
> >> index 1cf6aeb..3067f39 100644
> >> --- a/lib/librte_eal/linuxapp/eal/eal_dev.c
> >> +++ b/lib/librte_eal/linuxapp/eal/eal_dev.c
> >> @@ -4,6 +4,8 @@
> >>
> >> #include <string.h>
> >> #include <unistd.h>
> >> +#include <fcntl.h>
> >> +#include <signal.h>
> >> #include <sys/socket.h>
> >> #include <linux/netlink.h>
> >>
> >> @@ -14,15 +16,27 @@
> >> #include <rte_malloc.h>
> >> #include <rte_interrupts.h>
> >> #include <rte_alarm.h>
> >> +#include <rte_bus.h>
> >> +#include <rte_eal.h>
> >> +#include <rte_spinlock.h>
> >>
> >> #include "eal_private.h"
> >>
> >> static struct rte_intr_handle intr_handle =3D {.fd =3D -1 };
> >> static bool monitor_started;
> >>
> >> +extern struct rte_bus_list rte_bus_list;
> >> +
> >> #define EAL_UEV_MSG_LEN 4096
> >> #define EAL_UEV_MSG_ELEM_LEN 128
> >>
> >> +/* spinlock for device failure process */
> >> +static rte_spinlock_t dev_failure_lock =3D RTE_SPINLOCK_INITIALIZER;
> >> +
> >> +static struct sigaction sigbus_action_old;
> >> +
> >> +static int sigbus_need_recover;
> >> +
> >> static void dev_uev_handler(__rte_unused void *param);
> >>
> >> /* identify the system layer which reports this event. */
> >> @@ -34,6 +48,93 @@ enum eal_dev_event_subsystem {
> >> };
> >>
> >> static int
> >> +dev_uev_failure_process(struct rte_device *dev, void *dev_addr)
> >> +{
> >> + struct rte_bus *bus;
> >> + int ret =3D 0;
> >> +
> >> + if (!dev && !dev_addr) {
> >> + return -EINVAL;
> >> + } else if (dev) {
> >> + bus =3D rte_bus_find_by_device_name(dev->name);
> >> + if (bus->handle_hot_unplug) {
> >> + /**
> >> + * call bus ops to handle hot unplug.
> >> + */
> >> + ret =3D bus->handle_hot_unplug(dev, dev_addr);
> >> + if (ret) {
> >> + RTE_LOG(ERR, EAL,
> >> + "Cannot handle hot unplug "
> >> + "for device %s "
> >> + "on the bus %s.\n ",
> >> + dev->name, bus->name);
> >> + }
> >> + } else {
> >> + RTE_LOG(ERR, EAL,
> >> + "Not support handle hot unplug for bus %s!\n",
> >> + bus->name);
> >> + ret =3D -ENOTSUP;
> >> + }
> >> + } else {
> >> + TAILQ_FOREACH(bus, &rte_bus_list, next) {
> >> + if (bus->handle_hot_unplug) {
> >> + /**
> >> + * call bus ops to handle hot unplug.
> >> + */
> >> + ret =3D bus->handle_hot_unplug(dev, dev_addr);
> >> + if (ret)
> >> + RTE_LOG(ERR, EAL,
> >> + "Cannot handle hot unplug "
> >> + "for the device "
> >> + "on the bus %s!\n", bus->name);
> >> + else
> >> + break;
> >> + } else {
> >> + RTE_LOG(ERR, EAL,
> >> + "Not support handle hot unplug "
> >> + "for bus %s!\n", bus->name);
> >> + ret =3D -ENOTSUP;
> >> + }
> >> + }
> >> + }
> >> + return ret;
> >> +}
> >> +
> >> +static void
> >> +sigbus_action_recover(void)
> >> +{
> >> + if (sigbus_need_recover) {
> >> + sigaction(SIGBUS, &sigbus_action_old, NULL);
> >> + sigbus_need_recover =3D 0;
> >> + }
> >> +}
> >> +
> >> +static void sigbus_handler(int signum __rte_unused, siginfo_t *info,
> >> + void *ctx __rte_unused)
> >> +{
> >> + int ret;
> >> +
> >> + RTE_LOG(DEBUG, EAL, "Thread[%d] catch SIGBUS, fault address:%p\n",
> >> + (int)pthread_self(), info->si_addr);
> >> + rte_spinlock_lock(&dev_failure_lock);
> >> + ret =3D dev_uev_failure_process(NULL, info->si_addr);
> >> + rte_spinlock_unlock(&dev_failure_lock);
> >> + if (!ret)
> >> + RTE_LOG(DEBUG, EAL,
> >> + "Success to handle SIGBUS error for hot unplug!\n");
> >> + else
> >> + rte_exit(EXIT_FAILURE, "exit for SIGBUS error!");
> > I still think we have to distinguish here 2 cases:
> > 1) failure addr is not belong to any dpdk devices
> > 2) failure addr does belong to dpdk device, but we fail to remap it.
> >
> > For 1) we probably need to call previous sigbus handler.
> > For 2) we probably can only do exit().
>=20
> i think the previous sigbus handler is just a exception of sigbus error
> and exit out of the process, so i think should use one way to handler
> 1)+2) should be fine, do you agree with that? or you could find any
> chance to
> call any other sigbus handler at this positoin?
I think application can have its own sigbus handler installed (same as we d=
o).
> >> +}
> >> +
> >> +static int cmp_dev_name(const struct rte_device *dev,
> >> + const void *_name)
> >> +{
> >> + const char *name =3D _name;
> >> +
> >> + return strcmp(dev->name, name);
> >> +}
> >> +
> >> +static int
> >> dev_uev_socket_fd_create(void)
> >> {
> >> struct sockaddr_nl addr;
> >> @@ -147,6 +248,9 @@ dev_uev_handler(__rte_unused void *param)
> >> struct rte_dev_event uevent;
> >> int ret;
> >> char buf[EAL_UEV_MSG_LEN];
> >> + struct rte_bus *bus;
> >> + struct rte_device *dev;
> >> + const char *busname;
> >>
> >> memset(&uevent, 0, sizeof(struct rte_dev_event));
> >> memset(buf, 0, EAL_UEV_MSG_LEN);
> >> @@ -171,13 +275,50 @@ dev_uev_handler(__rte_unused void *param)
> >> RTE_LOG(DEBUG, EAL, "receive uevent(name:%s, type:%d, subsystem:%d)=
\n",
> >> uevent.devname, uevent.type, uevent.subsystem);
> >>
> >> - if (uevent.devname)
> >> + switch (uevent.subsystem) {
> >> + case EAL_DEV_EVENT_SUBSYSTEM_PCI:
> >> + case EAL_DEV_EVENT_SUBSYSTEM_UIO:
> >> + busname =3D "pci";
> >> + break;
> >> + default:
> >> + break;
> >> + }
> >> +
> >> + if (uevent.devname) {
> >> + if (uevent.type =3D=3D RTE_DEV_EVENT_REMOVE) {
> >> + bus =3D rte_bus_find_by_name(busname);
> >> + if (bus =3D=3D NULL) {
> >> + RTE_LOG(ERR, EAL, "Cannot find bus (%s)\n",
> >> + uevent.devname);
> >> + return;
> >> + }
> >> + dev =3D bus->find_device(NULL, cmp_dev_name,
> >> + uevent.devname);
> >> + if (dev =3D=3D NULL) {
> >> + RTE_LOG(ERR, EAL,
> >> + "Cannot find unplugged device (%s)\n",
> >> + uevent.devname);
> >> + return;
> >> + }
> >> + rte_spinlock_lock(&dev_failure_lock);
> >> + ret =3D dev_uev_failure_process(dev, NULL);
> >> + rte_spinlock_unlock(&dev_failure_lock);
> > That's interrupt thread, right?
> > I wonder could it happen that user will call device_detach() at the sam=
e moment?
> > Konstantin
>=20
> it is in interrupt thread, and user will call device_detach after failure=
process, you concern about twice or more device detach? i
> don't think is there any problem here.
Ok, but user can call device_detach() on his own, without waiting for failu=
re to happen, right?
>=20
> >> + if (ret) {
> >> + RTE_LOG(ERR, EAL, "Driver cannot remap the "
> >> + "device (%s)\n",
> >> + dev->name);
> >> + return;
> >> + }
> >> + }
> >> dev_callback_process(uevent.devname, uevent.type);
> >> + }
> >> }
> >>
> >> int __rte_experimental
> >> rte_dev_event_monitor_start(void)
> >> {
> >> + sigset_t mask;
> >> + struct sigaction action;
> >> int ret;
> >>
> >> if (monitor_started)
> >> @@ -197,6 +338,14 @@ rte_dev_event_monitor_start(void)
> >> return -1;
> >> }
> >>
> >> + /* register sigbus handler */
> >> + sigemptyset(&mask);
> >> + sigaddset(&mask, SIGBUS);
> >> + action.sa_flags =3D SA_SIGINFO;
> >> + action.sa_mask =3D mask;
> >> + action.sa_sigaction =3D sigbus_handler;
> >> + sigbus_need_recover =3D !sigaction(SIGBUS, &action, &sigbus_action_o=
ld);
> >> +
> >> monitor_started =3D true;
> >>
> >> return 0;
> >> @@ -217,8 +366,11 @@ rte_dev_event_monitor_stop(void)
> >> return ret;
> >> }
> >>
> >> + sigbus_action_recover();
> >> +
> >> close(intr_handle.fd);
> >> intr_handle.fd =3D -1;
> >> monitor_started =3D false;
> >> +
> >> return 0;
> >> }
> >> --
> >> 2.7.4