forked from Minki/linux
56 lines
1.5 KiB
ReStructuredText
56 lines
1.5 KiB
ReStructuredText
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===============================
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The Linux Kernel Tracepoint API
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===============================
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:Author: Jason Baron
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:Author: William Cohen
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Introduction
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============
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Tracepoints are static probe points that are located in strategic points
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throughout the kernel. 'Probes' register/unregister with tracepoints via
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a callback mechanism. The 'probes' are strictly typed functions that are
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passed a unique set of parameters defined by each tracepoint.
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From this simple callback mechanism, 'probes' can be used to profile,
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debug, and understand kernel behavior. There are a number of tools that
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provide a framework for using 'probes'. These tools include Systemtap,
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ftrace, and LTTng.
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Tracepoints are defined in a number of header files via various macros.
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Thus, the purpose of this document is to provide a clear accounting of
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the available tracepoints. The intention is to understand not only what
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tracepoints are available but also to understand where future
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tracepoints might be added.
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The API presented has functions of the form:
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``trace_tracepointname(function parameters)``. These are the tracepoints
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callbacks that are found throughout the code. Registering and
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unregistering probes with these callback sites is covered in the
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``Documentation/trace/*`` directory.
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IRQ
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===
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.. kernel-doc:: include/trace/events/irq.h
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:internal:
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SIGNAL
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======
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.. kernel-doc:: include/trace/events/signal.h
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:internal:
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Block IO
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========
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.. kernel-doc:: include/trace/events/block.h
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:internal:
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Workqueue
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=========
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.. kernel-doc:: include/trace/events/workqueue.h
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:internal:
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