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/** @mainpage SystemTap Runtime Library
*
* @section intro_sec Introduction
*
* The SystemTap Runtime Library consists of all functions
* and code fragments needed by the compiler/translator to
* include in building a kernel module using kprobes.
*
* @section design_sec Design
* @subsection map_sec Maps (Associative Arrays)
* Maps are implemented as hash lists. It is not expected that users will
* attempt to collect so much data in kernel space that performance problems will require
* more complex solutions such as AVL trees.
*
* Maps are created with _stp_map_new(). Each map can hold only one type of
* data; int64, string, or statistics. Each element belonging to a map can have up to 2 keys
* and a value. Implemented key types are strings and longs.
*
* To simplify the implementation, the functions to set the key and the functions to set the data are separated.
* That means we need only 4 functions to set the key and 3 functions to set the value.
*
* For example:
* @include map.c
* All elements have a default value of 0 (or NULL). Elements are only saved to the map when their value is set
* to something nonzero. This means that querying for the existance of a key is inexpensive because
* no element is created, just a hash table lookup.
*
* A list is a special map which has internally ascending long integer keys. Adding a value to
* a list does not require setting a key first. See _stp_list_add_str() and _stp_list_add_int64().
*
* @section status_sec Status
* Maps are implemented and tested. Histograms are not yet finished.
*
* Copy_From_User functions are done.
*
* If maps overflow or memory runs out for some reason, globals are set but nothing is done yet.
* I expect to implement a function to tell the system to either ignore it or unload the module and quit.
*
* Working sample probe code using the runtime is in tests/test4_probe and tests/shellprobe.
*
* @todo The Runtime Library is not actually a library yet. It is just a collection of functions
* included in the probe boilerplate.
*
*/
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