From: Andrew Rybchenko <arybchenko@solarflare.com>
To: Jeff Guo <jia.guo@intel.com>, <stephen@networkplumber.org>,
<bruce.richardson@intel.com>, <ferruh.yigit@intel.com>,
<konstantin.ananyev@intel.com>, <gaetan.rivet@6wind.com>,
<jingjing.wu@intel.com>, <thomas@monjalon.net>,
<motih@mellanox.com>, <matan@mellanox.com>,
<harry.van.haaren@intel.com>, <qi.z.zhang@intel.com>,
<shaopeng.he@intel.com>, <bernard.iremonger@intel.com>,
<arybchenko@solarflare.com>
Cc: <jblunck@infradead.org>, <shreyansh.jain@nxp.com>, <dev@dpdk.org>,
<helin.zhang@intel.com>, Shreyansh Jain <shreyansh.jain@nxp.com>
Subject: Re: [dpdk-dev] [PATCH v6 6/7] eal: add failure handle mechanism for hotplug
Date: Mon, 9 Jul 2018 09:47:05 +0300 [thread overview]
Message-ID: <6a0473c8-2c5c-8c33-e6e1-46c439a94f9f@solarflare.com> (raw)
In-Reply-To: <1531116091-18030-7-git-send-email-jia.guo@intel.com>
CC Shreyansh
On 09.07.2018 09:01, Jeff Guo wrote:
> This patch introduces a failure handle mechanism to handle device
> hotplug removal event.
>
> First it can register sigbus handler when enable device event monitor. Once
> sigbus error be captured, it will check the failure address and accordingly
> remap the invalid memory for the corresponding device. Besed on this
> mechanism, it could guaranty the application not crash when the device be
> hotplug out.
>
> Signed-off-by: Jeff Guo <jia.guo@intel.com>
> Acked-by: Shaopeng He <shaopeng.he@intel.com>
> ---
> v6->v5:
> refine some doc and coding style
> ---
> lib/librte_eal/linuxapp/eal/eal_dev.c | 114 +++++++++++++++++++++++++++++++++-
> 1 file changed, 113 insertions(+), 1 deletion(-)
>
> diff --git a/lib/librte_eal/linuxapp/eal/eal_dev.c b/lib/librte_eal/linuxapp/eal/eal_dev.c
> index 1cf6aeb..cb30729 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 +16,31 @@
> #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 <rte_errno.h>
>
> #include "eal_private.h"
>
> static struct rte_intr_handle intr_handle = {.fd = -1 };
> static bool monitor_started;
>
> +extern struct rte_bus_list rte_bus_list;
> +
Shreyansh, shouldn't it be done in rte_bus.h?
> #define EAL_UEV_MSG_LEN 4096
> #define EAL_UEV_MSG_ELEM_LEN 128
>
> +/*
> + * spinlock for device failure process, protect the bus and the device
> + * to avoid race condition.
> + */
> +static rte_spinlock_t dev_failure_lock = RTE_SPINLOCK_INITIALIZER;
Unfortunately it is still not very helpful. I don't understand circumstance
when the race condition could happen.
> +
> +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. */
> @@ -33,6 +51,49 @@ enum eal_dev_event_subsystem {
> EAL_DEV_EVENT_SUBSYSTEM_MAX
> };
>
> +static void
> +sigbus_action_recover(void)
> +{
> + if (sigbus_need_recover) {
> + sigaction(SIGBUS, &sigbus_action_old, NULL);
> + sigbus_need_recover = 0;
> + }
> +}
> +
> +static void sigbus_handler(int signum, siginfo_t *info,
> + void *ctx __rte_unused)
> +{
> + int ret;
> +
> + RTE_LOG(INFO, EAL, "Thread[%d] catch SIGBUS, fault address:%p\n",
> + (int)pthread_self(), info->si_addr);
> +
> + rte_spinlock_lock(&dev_failure_lock);
> + ret = rte_bus_sigbus_handler(info->si_addr);
> + rte_spinlock_unlock(&dev_failure_lock);
> + if (ret == -1) {
> + rte_exit(EXIT_FAILURE,
> + "Failed to handle SIGBUS for hotplug, "
> + "(rte_errno: %s)!", strerror(rte_errno));
> + } else if (ret == 1) {
> + if (sigbus_action_old.sa_handler)
> + (*(sigbus_action_old.sa_handler))(signum);
> + else
> + rte_exit(EXIT_FAILURE,
> + "Failed to handle generic SIGBUS!");
> + }
> +
> + RTE_LOG(INFO, EAL, "Success to handle SIGBUS for hotplug!\n");
> +}
> +
> +static int cmp_dev_name(const struct rte_device *dev,
> + const void *_name)
> +{
> + const char *name = _name;
> +
> + return strcmp(dev->name, name);
> +}
> +
> static int
> dev_uev_socket_fd_create(void)
> {
> @@ -147,6 +208,9 @@ 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 +235,50 @@ 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 = "pci";
> + break;
> + default:
> + break;
> + }
> +
> + if (uevent.devname) {
> + if (uevent.type == RTE_DEV_EVENT_REMOVE) {
> + rte_spinlock_lock(&dev_failure_lock);
> + bus = rte_bus_find_by_name(busname);
I see no point find bus by empty name. I would suggest to initialize
busname to NULL and simply would not even try to find bus with
such name. Just check above and generate appropriate log.
> + if (bus == NULL) {
> + RTE_LOG(ERR, EAL, "Cannot find bus (%s)\n",
> + busname);
> + return;
> + }
> +
> + dev = bus->find_device(NULL, cmp_dev_name,
> + uevent.devname);
> + if (dev == NULL) {
> + RTE_LOG(ERR, EAL, "Cannot find device (%s) on "
> + "bus (%s)\n", uevent.devname, busname);
> + return;
> + }
> +
> + ret = bus->hotplug_failure_handler(dev);
> + rte_spinlock_unlock(&dev_failure_lock);
> + if (ret) {
> + RTE_LOG(ERR, EAL, "Can not handle hotplug for "
> + "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 +298,14 @@ rte_dev_event_monitor_start(void)
> return -1;
> }
>
> + /* register sigbus handler */
> + sigemptyset(&mask);
> + sigaddset(&mask, SIGBUS);
> + action.sa_flags = SA_SIGINFO;
> + action.sa_mask = mask;
> + action.sa_sigaction = sigbus_handler;
> + sigbus_need_recover = !sigaction(SIGBUS, &action, &sigbus_action_old);
> +
> monitor_started = true;
>
> return 0;
> @@ -217,8 +326,11 @@ rte_dev_event_monitor_stop(void)
> return ret;
> }
>
> + sigbus_action_recover();
> +
> close(intr_handle.fd);
> intr_handle.fd = -1;
> monitor_started = false;
> +
> return 0;
> }
next prev parent reply other threads:[~2018-07-09 6:47 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-09 6:01 [dpdk-dev] [PATCH v6 0/7] hotplug failure handle mechanism Jeff Guo
2018-07-09 6:01 ` [dpdk-dev] [PATCH v6 1/7] bus: add hotplug failure handler Jeff Guo
2018-07-09 6:01 ` [dpdk-dev] [PATCH v6 2/7] bus/pci: implement hotplug failure handler ops Jeff Guo
2018-07-09 6:01 ` [dpdk-dev] [PATCH v6 3/7] bus: add sigbus handler Jeff Guo
2018-07-09 6:01 ` [dpdk-dev] [PATCH v6 4/7] bus/pci: implement sigbus handler operation Jeff Guo
2018-07-09 6:01 ` [dpdk-dev] [PATCH v6 5/7] bus: add helper to handle sigbus Jeff Guo
2018-07-09 6:36 ` Andrew Rybchenko
2018-07-09 6:01 ` [dpdk-dev] [PATCH v6 6/7] eal: add failure handle mechanism for hotplug Jeff Guo
2018-07-09 6:47 ` Andrew Rybchenko [this message]
2018-07-09 6:01 ` [dpdk-dev] [PATCH v6 7/7] igb_uio: fix uio release issue when hot unplug Jeff Guo
-- strict thread matches above, loose matches on Subject: below --
2017-06-29 4:37 [dpdk-dev] [PATCH v3 0/2] add uevent api for hot plug Jeff Guo
2018-07-09 6:51 ` [dpdk-dev] [PATCH v6 0/7] hotplug failure handle mechanism Jeff Guo
2018-07-09 6:51 ` [dpdk-dev] [PATCH v6 6/7] eal: add failure handle mechanism for hotplug Jeff Guo
2018-07-09 7:42 ` Gaëtan Rivet
2018-07-09 8:12 ` Jeff Guo
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=6a0473c8-2c5c-8c33-e6e1-46c439a94f9f@solarflare.com \
--to=arybchenko@solarflare.com \
--cc=bernard.iremonger@intel.com \
--cc=bruce.richardson@intel.com \
--cc=dev@dpdk.org \
--cc=ferruh.yigit@intel.com \
--cc=gaetan.rivet@6wind.com \
--cc=harry.van.haaren@intel.com \
--cc=helin.zhang@intel.com \
--cc=jblunck@infradead.org \
--cc=jia.guo@intel.com \
--cc=jingjing.wu@intel.com \
--cc=konstantin.ananyev@intel.com \
--cc=matan@mellanox.com \
--cc=motih@mellanox.com \
--cc=qi.z.zhang@intel.com \
--cc=shaopeng.he@intel.com \
--cc=shreyansh.jain@nxp.com \
--cc=stephen@networkplumber.org \
--cc=thomas@monjalon.net \
/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).