35 lines
1.5 KiB
Plaintext
35 lines
1.5 KiB
Plaintext
The VFS trace plugin offers access to Genode's trace session by providing a
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file-system that can be mounted at arbitrary location within the VFS of a
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component. The file system forms a directory structure that recursively
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represents the parent-child relationship of running component. The leave
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directories represent the threads within a component. Currently there are three
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files for each thread that can be accessed:
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:'enable': Start or stops tracing of a thread by write "true" or "false" into
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file.
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:'buffer_size': Allows the configuration of the trace-buffer size for the
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thread in the usual Genode format (e.g. 5M, 512K, 1024).
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:'trace_buffer': This read only file contains the current content of the trace
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buffer. Every trace entry can only be read once, after that
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only new entries appear. "tail -f" can also be used in order to
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display continuous output.
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In order to mount the file system configure the <vfs> of your component as
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follow:
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! <vfs>
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! <trace ram="16M"/>
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! </vfs>
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The "ram" attribute is mandatory and configures the quota of the trace-session
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in the plugin. It limits the number of thread that can be traced at once.
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Limitations:
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The plugin retrieves up to 128 running components at load time. There is
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currently no support to add or remove components once the plugin has been
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started. This implies that components that are started at a later stage will not
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appear within the file system.
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