Sample Implementation of Intel MIC User Space Daemon.
This patch introduces a sample user space daemon which implements the virtio device backends on the host. The daemon creates/removes/configures virtio device backends by communicating with the Intel MIC Host Driver. The virtio devices currently supported are virtio net, virtio console and virtio block. Virtio net supports TSO/GSO. The daemon also monitors card shutdown status and takes appropriate actions like killing the virtio backends and resetting the card upon card shutdown and crashes. Co-author: Ashutosh Dixit <ashutosh.dixit@intel.com> Co-author: Sudeep Dutt <sudeep.dutt@intel.com> Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com> Signed-off-by: Caz Yokoyama <Caz.Yokoyama@intel.com> Signed-off-by: Dasaratharaman Chandramouli <dasaratharaman.chandramouli@intel.com> Signed-off-by: Nikhil Rao <nikhil.rao@intel.com> Signed-off-by: Harshavardhan R Kharche <harshavardhan.r.kharche@intel.com> Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com> Acked-by: Yaozu (Eddie) Dong <eddie.dong@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>hifive-unleashed-5.1
Caz Yokoyama
Greg Kroah-Hartman
parent
2141c7c5ee
commit
8d49751580
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@ -0,0 +1,49 @@
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An Intel MIC X100 device is a PCIe form factor add-in coprocessor
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card based on the Intel Many Integrated Core (MIC) architecture
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that runs a Linux OS. It is a PCIe endpoint in a platform and therefore
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implements the three required standard address spaces i.e. configuration,
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memory and I/O. The host OS loads a device driver as is typical for
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PCIe devices. The card itself runs a bootstrap after reset that
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transfers control to the card OS downloaded from the host driver.
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The card OS as shipped by Intel is a Linux kernel with modifications
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for the X100 devices.
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Since it is a PCIe card, it does not have the ability to host hardware
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devices for networking, storage and console. We provide these devices
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on X100 coprocessors thus enabling a self-bootable equivalent environment
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for applications. A key benefit of our solution is that it leverages
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the standard virtio framework for network, disk and console devices,
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though in our case the virtio framework is used across a PCIe bus.
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Here is a block diagram of the various components described above. The
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virtio backends are situated on the host rather than the card given better
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single threaded performance for the host compared to MIC, the ability of
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the host to initiate DMA's to/from the card using the MIC DMA engine and
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the fact that the virtio block storage backend can only be on the host.
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+----------+ | +----------+
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| Card OS | | | Host OS |
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+----------+ | +----------+
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+-------+ +--------+ +------+ | +---------+ +--------+ +--------+
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| Virtio| |Virtio | |Virtio| | |Virtio | |Virtio | |Virtio |
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| Net | |Console | |Block | | |Net | |Console | |Block |
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| Driver| |Driver | |Driver| | |backend | |backend | |backend |
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+-------+ +--------+ +------+ | +---------+ +--------+ +--------+
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| | | | | | |
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| | | |User | | |
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| | | |------|------------|---------|-------
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+-------------------+ |Kernel +--------------------------+
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| | | Virtio over PCIe IOCTLs |
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| | +--------------------------+
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+--------------+ | |
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|Intel MIC | | +---------------+
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|Card Driver | | |Intel MIC |
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+--------------+ | |Host Driver |
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| | +---------------+
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| | |
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+-------------------------------------------------------------+
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| |
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| PCIe Bus |
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+-------------------------------------------------------------+
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@ -0,0 +1 @@
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mpssd
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@ -0,0 +1,19 @@
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#
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# Makefile - Intel MIC User Space Tools.
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# Copyright(c) 2013, Intel Corporation.
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#
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ifdef DEBUG
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CFLAGS += $(USERWARNFLAGS) -I. -g -Wall -DDEBUG=$(DEBUG)
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else
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CFLAGS += $(USERWARNFLAGS) -I. -g -Wall
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endif
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mpssd: mpssd.o sysfs.o
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$(CC) $(CFLAGS) -o $@ $^ -lpthread
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install:
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install mpssd /usr/sbin/mpssd
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install micctrl /usr/sbin/micctrl
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clean:
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rm -f mpssd *.o
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@ -0,0 +1,173 @@
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#!/bin/bash
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# Intel MIC Platform Software Stack (MPSS)
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#
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# Copyright(c) 2013 Intel Corporation.
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License, version 2, as
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# published by the Free Software Foundation.
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#
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# This program is distributed in the hope that it will be useful, but
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# WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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# General Public License for more details.
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#
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# The full GNU General Public License is included in this distribution in
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# the file called "COPYING".
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#
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# Intel MIC User Space Tools.
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#
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# micctrl - Controls MIC boot/start/stop.
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#
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# chkconfig: 2345 95 05
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# description: start MPSS stack processing.
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#
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### BEGIN INIT INFO
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# Provides: micctrl
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### END INIT INFO
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# Source function library.
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. /etc/init.d/functions
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sysfs="/sys/class/mic"
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_status()
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{
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f=$sysfs/$1
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echo -e $1 state: "`cat $f/state`" shutdown_status: "`cat $f/shutdown_status`"
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}
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status()
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{
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if [ "`echo $1 | head -c3`" == "mic" ]; then
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_status $1
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return $?
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fi
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for f in $sysfs/*
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do
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_status `basename $f`
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RETVAL=$?
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[ $RETVAL -ne 0 ] && return $RETVAL
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done
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return 0
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}
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_reset()
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{
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f=$sysfs/$1
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echo reset > $f/state
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}
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reset()
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{
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if [ "`echo $1 | head -c3`" == "mic" ]; then
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_reset $1
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return $?
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fi
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for f in $sysfs/*
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do
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_reset `basename $f`
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RETVAL=$?
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[ $RETVAL -ne 0 ] && return $RETVAL
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done
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return 0
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}
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_boot()
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{
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f=$sysfs/$1
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echo "linux" > $f/bootmode
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echo "mic/uos.img" > $f/firmware
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echo "mic/$1.image" > $f/ramdisk
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echo "boot" > $f/state
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}
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boot()
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{
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if [ "`echo $1 | head -c3`" == "mic" ]; then
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_boot $1
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return $?
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fi
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for f in $sysfs/*
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do
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_boot `basename $f`
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RETVAL=$?
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[ $RETVAL -ne 0 ] && return $RETVAL
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done
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return 0
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}
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_shutdown()
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{
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f=$sysfs/$1
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echo shutdown > $f/state
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}
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shutdown()
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{
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if [ "`echo $1 | head -c3`" == "mic" ]; then
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_shutdown $1
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return $?
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fi
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for f in $sysfs/*
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do
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_shutdown `basename $f`
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RETVAL=$?
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[ $RETVAL -ne 0 ] && return $RETVAL
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done
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return 0
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}
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_wait()
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{
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f=$sysfs/$1
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while [ "`cat $f/state`" != "offline" -a "`cat $f/state`" != "online" ]
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do
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sleep 1
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echo -e "Waiting for $1 to go offline"
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done
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}
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wait()
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{
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if [ "`echo $1 | head -c3`" == "mic" ]; then
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_wait $1
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return $?
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fi
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# Wait for the cards to go offline
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for f in $sysfs/*
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do
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_wait `basename $f`
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RETVAL=$?
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[ $RETVAL -ne 0 ] && return $RETVAL
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done
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return 0
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}
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if [ ! -d "$sysfs" ]; then
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echo -e $"Module unloaded "
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exit 3
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fi
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case $1 in
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-s)
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status $2
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;;
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-r)
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reset $2
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;;
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-b)
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boot $2
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;;
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-S)
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shutdown $2
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;;
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-w)
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wait $2
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;;
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*)
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echo $"Usage: $0 {-s (status) |-r (reset) |-b (boot) |-S (shutdown) |-w (wait)}"
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exit 2
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esac
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exit $?
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@ -0,0 +1,202 @@
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#!/bin/bash
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# Intel MIC Platform Software Stack (MPSS)
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#
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# Copyright(c) 2013 Intel Corporation.
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License, version 2, as
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# published by the Free Software Foundation.
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#
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# This program is distributed in the hope that it will be useful, but
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# WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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# General Public License for more details.
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#
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# The full GNU General Public License is included in this distribution in
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# the file called "COPYING".
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#
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# Intel MIC User Space Tools.
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#
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# mpss Start mpssd.
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#
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# chkconfig: 2345 95 05
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# description: start MPSS stack processing.
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#
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### BEGIN INIT INFO
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# Provides: mpss
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# Required-Start:
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# Required-Stop:
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# Short-Description: MPSS stack control
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# Description: MPSS stack control
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### END INIT INFO
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# Source function library.
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. /etc/init.d/functions
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exec=/usr/sbin/mpssd
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sysfs="/sys/class/mic"
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start()
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{
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[ -x $exec ] || exit 5
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if [ "`ps -e | awk '{print $4}' | grep mpssd | head -1`" = "mpssd" ]; then
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echo -e $"MPSSD already running! "
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success
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echo
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return 0
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fi
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echo -e $"Starting MPSS Stack"
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echo -e $"Loading MIC_HOST Module"
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# Ensure the driver is loaded
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if [ ! -d "$sysfs" ]; then
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modprobe mic_host
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RETVAL=$?
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if [ $RETVAL -ne 0 ]; then
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failure
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echo
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return $RETVAL
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fi
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fi
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# Start the daemon
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echo -n $"Starting MPSSD "
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$exec
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RETVAL=$?
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if [ $RETVAL -ne 0 ]; then
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failure
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echo
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return $RETVAL
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fi
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success
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echo
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sleep 5
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# Boot the cards
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micctrl -b
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# Wait till ping works
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for f in $sysfs/*
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do
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count=100
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ipaddr=`cat $f/cmdline`
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ipaddr=${ipaddr#*address,}
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ipaddr=`echo $ipaddr | cut -d, -f1 | cut -d\; -f1`
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while [ $count -ge 0 ]
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do
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echo -e "Pinging "`basename $f`" "
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ping -c 1 $ipaddr &> /dev/null
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RETVAL=$?
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if [ $RETVAL -eq 0 ]; then
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success
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break
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fi
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sleep 1
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count=`expr $count - 1`
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done
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[ $RETVAL -ne 0 ] && failure || success
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echo
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done
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return $RETVAL
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}
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stop()
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{
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echo -e $"Shutting down MPSS Stack: "
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# Bail out if module is unloaded
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if [ ! -d "$sysfs" ]; then
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echo -n $"Module unloaded "
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success
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echo
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return 0
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fi
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# Shut down the cards.
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micctrl -S
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# Wait for the cards to go offline
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for f in $sysfs/*
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do
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while [ "`cat $f/state`" != "offline" ]
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do
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sleep 1
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echo -e "Waiting for "`basename $f`" to go offline"
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done
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done
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# Display the status of the cards
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micctrl -s
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# Kill MPSSD now
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echo -n $"Killing MPSSD"
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killall -9 mpssd 2>/dev/null
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RETVAL=$?
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[ $RETVAL -ne 0 ] && failure || success
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echo
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return $RETVAL
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}
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restart()
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{
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stop
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sleep 5
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start
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}
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status()
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{
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micctrl -s
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if [ "`ps -e | awk '{print $4}' | grep mpssd | head -n 1`" = "mpssd" ]; then
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echo "mpssd is running"
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else
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echo "mpssd is stopped"
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fi
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return 0
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}
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unload()
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{
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if [ ! -d "$sysfs" ]; then
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echo -n $"No MIC_HOST Module: "
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success
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echo
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return
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fi
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stop
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sleep 5
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echo -n $"Removing MIC_HOST Module: "
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modprobe -r mic_host
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RETVAL=$?
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[ $RETVAL -ne 0 ] && failure || success
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echo
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return $RETVAL
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}
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case $1 in
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start)
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start
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;;
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stop)
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stop
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;;
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restart)
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restart
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;;
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status)
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status
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;;
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unload)
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unload
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;;
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*)
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echo $"Usage: $0 {start|stop|restart|status|unload}"
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exit 2
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esac
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exit $?
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File diff suppressed because it is too large
Load Diff
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@ -0,0 +1,100 @@
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/*
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* Intel MIC Platform Software Stack (MPSS)
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*
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* Copyright(c) 2013 Intel Corporation.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License, version 2, as
|
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* published by the Free Software Foundation.
|
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*
|
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* This program is distributed in the hope that it will be useful, but
|
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* WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
* General Public License for more details.
|
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*
|
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* The full GNU General Public License is included in this distribution in
|
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* the file called "COPYING".
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*
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* Intel MIC User Space Tools.
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*/
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#ifndef _MPSSD_H_
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#define _MPSSD_H_
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <dirent.h>
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#include <libgen.h>
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#include <pthread.h>
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#include <stdarg.h>
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#include <time.h>
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#include <errno.h>
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#include <sys/dir.h>
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#include <sys/ioctl.h>
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#include <sys/poll.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <sys/stat.h>
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#include <sys/types.h>
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#include <sys/mman.h>
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#include <sys/utsname.h>
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#include <sys/wait.h>
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#include <netinet/in.h>
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#include <arpa/inet.h>
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#include <netdb.h>
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#include <pthread.h>
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#include <signal.h>
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#include <limits.h>
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#include <syslog.h>
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#include <getopt.h>
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#include <net/if.h>
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#include <linux/if_tun.h>
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#include <linux/if_tun.h>
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#include <linux/virtio_ids.h>
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#define MICSYSFSDIR "/sys/class/mic"
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#define LOGFILE_NAME "/var/log/mpssd"
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#define PAGE_SIZE 4096
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struct mic_console_info {
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pthread_t console_thread;
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int virtio_console_fd;
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void *console_dp;
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};
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struct mic_net_info {
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pthread_t net_thread;
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int virtio_net_fd;
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int tap_fd;
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void *net_dp;
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};
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struct mic_virtblk_info {
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pthread_t block_thread;
|
||||
int virtio_block_fd;
|
||||
void *block_dp;
|
||||
volatile sig_atomic_t signaled;
|
||||
char *backend_file;
|
||||
int backend;
|
||||
void *backend_addr;
|
||||
long backend_size;
|
||||
};
|
||||
|
||||
struct mic_info {
|
||||
int id;
|
||||
char *name;
|
||||
pthread_t config_thread;
|
||||
pid_t pid;
|
||||
struct mic_console_info mic_console;
|
||||
struct mic_net_info mic_net;
|
||||
struct mic_virtblk_info mic_virtblk;
|
||||
int restart;
|
||||
struct mic_info *next;
|
||||
};
|
||||
|
||||
void mpsslog(char *format, ...);
|
||||
char *readsysfs(char *dir, char *entry);
|
||||
int setsysfs(char *dir, char *entry, char *value);
|
||||
#endif
|
||||
|
|
@ -0,0 +1,102 @@
|
|||
/*
|
||||
* Intel MIC Platform Software Stack (MPSS)
|
||||
*
|
||||
* Copyright(c) 2013 Intel Corporation.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License, version 2, as
|
||||
* published by the Free Software Foundation.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful, but
|
||||
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
* General Public License for more details.
|
||||
*
|
||||
* The full GNU General Public License is included in this distribution in
|
||||
* the file called "COPYING".
|
||||
*
|
||||
* Intel MIC User Space Tools.
|
||||
*/
|
||||
|
||||
#include "mpssd.h"
|
||||
|
||||
#define PAGE_SIZE 4096
|
||||
|
||||
char *
|
||||
readsysfs(char *dir, char *entry)
|
||||
{
|
||||
char filename[PATH_MAX];
|
||||
char value[PAGE_SIZE];
|
||||
char *string = NULL;
|
||||
int fd;
|
||||
int len;
|
||||
|
||||
if (dir == NULL)
|
||||
snprintf(filename, PATH_MAX, "%s/%s", MICSYSFSDIR, entry);
|
||||
else
|
||||
snprintf(filename, PATH_MAX,
|
||||
"%s/%s/%s", MICSYSFSDIR, dir, entry);
|
||||
|
||||
fd = open(filename, O_RDONLY);
|
||||
if (fd < 0) {
|
||||
mpsslog("Failed to open sysfs entry '%s': %s\n",
|
||||
filename, strerror(errno));
|
||||
return NULL;
|
||||
}
|
||||
|
||||
len = read(fd, value, sizeof(value));
|
||||
if (len < 0) {
|
||||
mpsslog("Failed to read sysfs entry '%s': %s\n",
|
||||
filename, strerror(errno));
|
||||
goto readsys_ret;
|
||||
}
|
||||
if (len == 0)
|
||||
goto readsys_ret;
|
||||
|
||||
value[len - 1] = '\0';
|
||||
|
||||
string = malloc(strlen(value) + 1);
|
||||
if (string)
|
||||
strcpy(string, value);
|
||||
|
||||
readsys_ret:
|
||||
close(fd);
|
||||
return string;
|
||||
}
|
||||
|
||||
int
|
||||
setsysfs(char *dir, char *entry, char *value)
|
||||
{
|
||||
char filename[PATH_MAX];
|
||||
char *oldvalue;
|
||||
int fd, ret = 0;
|
||||
|
||||
if (dir == NULL)
|
||||
snprintf(filename, PATH_MAX, "%s/%s", MICSYSFSDIR, entry);
|
||||
else
|
||||
snprintf(filename, PATH_MAX, "%s/%s/%s",
|
||||
MICSYSFSDIR, dir, entry);
|
||||
|
||||
oldvalue = readsysfs(dir, entry);
|
||||
|
||||
fd = open(filename, O_RDWR);
|
||||
if (fd < 0) {
|
||||
ret = errno;
|
||||
mpsslog("Failed to open sysfs entry '%s': %s\n",
|
||||
filename, strerror(errno));
|
||||
goto done;
|
||||
}
|
||||
|
||||
if (!oldvalue || strcmp(value, oldvalue)) {
|
||||
if (write(fd, value, strlen(value)) < 0) {
|
||||
ret = errno;
|
||||
mpsslog("Failed to write new sysfs entry '%s': %s\n",
|
||||
filename, strerror(errno));
|
||||
}
|
||||
}
|
||||
close(fd);
|
||||
done:
|
||||
if (oldvalue)
|
||||
free(oldvalue);
|
||||
return ret;
|
||||
}
|
||||
Loading…
Reference in New Issue