Lines Matching refs:trace

1 Trace Agent for virtio-trace
4 Trace agent is a user tool for sending trace data of a guest to a Host in low
8  - write trace data to stdout by using -o option
11 The trace agent operates as follows:
16  4) After the controller of the trace agent receives a start order from a host,
18  5) The read/write threads start to read trace data from ring-buffers and
21     stop to read trace data.
28 Makefile: Makefile of trace agent for virtio-trace
29 trace-agent.c: includes main function, sets up for operating trace agent
30 trace-agent.h: includes all structures and some macros
31 trace-agent-ctl.c: includes controller function for read/write threads
32 trace-agent-rw.c: includes read/write threads function
38 To use this trace agent for virtio-trace, we need to prepare some virtio-serial
42  virtio-trace uses virtio-serial pipe as trace data paths as to the number
44 	# mkdir /tmp/virtio-trace/
45 	# mkfifo /tmp/virtio-trace/trace-path-cpu{0,1,2,...,X}.{in,out}
46 	# mkfifo /tmp/virtio-trace/agent-ctl-path.{in,out}
49 	trace-path-cpu{0,1,2}.{in.out}
59      -chardev pipe,id=charchannel0,path=/tmp/virtio-trace/agent-ctl-path\
63      -chardev pipe,id=charchannel1,path=/tmp/virtio-trace/trace-path-cpu0\
65       id=channel1,name=trace-path-cpu0\
72 	   <source path='/tmp/virtio-trace/agent-ctl-path'/>
77 	   <source path='/tmp/virtio-trace/trace-path-cpu0'/>
78 	   <target type='virtio' name='trace-path-cpu0'/>
82 Here, chardev names are restricted to trace-path-cpuX and agent-ctl-path. For
83 example, if a guest use three CPUs, chardev names should be trace-path-cpu0,
84 trace-path-cpu1, trace-path-cpu2, and agent-ctl-path.
93 0) Build trace agent in a guest
100 2) Run trace agent in the guest
102 	# ./trace-agent
104 option, trace data are output via stdout in the guest.
107 	# cat /tmp/virtio-trace/trace-path-cpu0.out
108 If a host does not open these, trace data get stuck in buffers of virtio. Then,
112 4) Start to read trace data by ordering from a host
114 	# echo 1 > /tmp/virtio-trace/agent-ctl-path.in
116 5) Stop to read trace data by ordering from a host
118 	# echo 0 > /tmp/virtio-trace/agent-ctl-path.in