/usr/share/systemtap/tapset/linux
Edit: /usr/share/systemtap/tapset/linux/ucontext-symbols.stp (8842B)
// User context symbols tapset
// Copyright (C) 2009-2016 Red Hat Inc.
//
// This file is part of systemtap, and is free software. You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.
//
// User context symbol functions provide additional information about
// addresses from an application. These functions can provide
// information about the user space map (library) that the event occurred or
// the function symbol of an address.
//
@__private30 function __ustack_raw:long (n:long) %{ /* pragma:unwind */ /* pure */
/* myproc-unprivileged */ /* pragma:uprobes */
/* basic sanity check for bounds: */
if (unlikely(STAP_ARG_n < 0 || STAP_ARG_n >= MAXBACKTRACE))
STAP_RETVALUE = 0;
else
STAP_RETVALUE = _stp_stack_user_get (CONTEXT, (unsigned)STAP_ARG_n);
%}
/**
* sfunction ustack - Return address at given depth of user stack backtrace
* @n: number of levels to descend in the stack.
*
* Description: Performs a simple (user space) backtrace, and returns the
* element at the specified position. The results of the backtrace itself
* are cached, so that the backtrace computation is performed at most once
* no matter how many times ustack() is called, or in what order.
*/
function ustack:long (n:long) {
__r = __ustack_raw(n);
if (__r != 0) return __r
/* fallback: parse backtrace() to go deeper in the stack */
__b = ubacktrace (); __orig_n = n;
__sym = tokenize (__b, " ");
if (__sym == "") @__context_unwind_error(__orig_n);
while (n > 0) {
__sym = tokenize ("", " ");
if (__sym == "") @__context_unwind_error(__orig_n);
n--;
}
return strtol(__sym, 16)
}
/**
* sfunction usymname - Return the symbol of an address in the current task.
* @addr: The address to translate.
*
* Description: Returns the (function) symbol name associated with the
* given address if known. If not known it will return the hex string
* representation of addr.
*/
function usymname:string (addr: long) %{
/* pure */ /* myproc-unprivileged */ /* pragma:vma */ /* pragma:symbols */
_stp_snprint_addr(STAP_RETVALUE, MAXSTRINGLEN, STAP_ARG_addr,
_STP_SYM_SYMBOL, current);
%}
/**
* sfunction usymdata - Return the symbol and module offset of an address.
* @addr: The address to translate.
*
* Description: Returns the (function) symbol name associated with the
* given address in the current task if known, the offset from the
* start and the size of the symbol, plus the module name (between
* brackets). If symbol is unknown, but module is known, the offset
* inside the module, plus the size of the module is added. If any
* element is not known it will be omitted and if the symbol name is
* unknown it will return the hex string for the given address.
*/
function usymdata:string (addr: long) %{
/* pure */ /* myproc-unprivileged */ /* pragma:vma */ /* pragma:symbols */
_stp_snprint_addr(STAP_RETVALUE, MAXSTRINGLEN, STAP_ARG_addr,
_STP_SYM_DATA, current);
%}
/**
* sfunction print_ustack - Print out stack for the current task from string.
* @stk: String with list of hexadecimal addresses for the current task.
*
* Perform a symbolic lookup of the addresses in the given string,
* which is assumed to be the result of a prior call to
* ubacktrace() for the current task.
*
* Print one line per address, including the address, the
* name of the function containing the address, and an estimate of
* its position within that function. Return nothing.
*
* NOTE: it is recommended to use print_usyms() instead of this function.
*/
function print_ustack(stk:string) { print_usyms(stk) }
/**
* sfunction print_usyms - Print out user stack from string
* @callers: String with list of hexadecimal (user) addresses
*
* Description: This function performs a symbolic lookup of the addresses
* in the given string,
* which are assumed to be the result of prior calls to ustack(),
* ucallers(), and similar functions.
*
* Prints one line per address, including the address, the
* name of the function containing the address, and an estimate of
* its position within that function, as obtained by usymdata().
* Returns nothing.
*/
function print_usyms (callers:string) {
__sym = tokenize (callers, " ");
while (__sym != "") {
printf (" %s : %s\n", __sym, usymdata (strtol(__sym,16)));
__sym = tokenize ("", " ");
}
}
/**
* sfunction sprint_ustack - Return stack for the current task from string.
* @stk: String with list of hexadecimal addresses for the current task.
*
* Perform a symbolic lookup of the addresses in the given string,
* which is assumed to be the result of a prior call to
* ubacktrace() for the current task.
*
* Returns a simple backtrace from the given hex string. One line per
* address. Includes the symbol name (or hex address if symbol
* couldn't be resolved) and module name (if found). Includes the
* offset from the start of the function if found, otherwise the
* offset will be added to the module (if found, between
* brackets). Returns the backtrace as string (each line terminated by
* a newline character). Note that the returned stack will be
* truncated to MAXSTRINGLEN, to print fuller and richer stacks use
* print_ustack.
*
* NOTE: it is recommended to use sprint_usyms() instead of this function.
*/
function sprint_ustack:string(stk:string) { return sprint_usyms(stk) }
/**
* sfunction sprint_usyms - Return stack for user addresses from string
*
* @callers: String with list of hexadecimal (user) addresses
*
* Perform a symbolic lookup of the addresses in the given string,
* which are assumed to be the result of a prior calls to ustack(),
* ucallers(), and similar functions.
*
* Returns a simple backtrace from the given hex string. One line per
* address. Includes the symbol name (or hex address if symbol
* couldn't be resolved) and module name (if found), as obtained from
* usymdata(). Includes the offset from the start of the function if
* found, otherwise the offset will be added to the module (if found, between
* brackets). Returns the backtrace as string (each line terminated by
* a newline character). Note that the returned stack will be
* truncated to MAXSTRINGLEN, to print fuller and richer stacks use
* print_usyms().
*/
function sprint_usyms (callers:string) {
__sym = tokenize (callers, " ");
__foo = ""; __l = 0
while (__sym != "") {
// cleanly handle overflow instead of printing partial line:
__line = sprintf (" %s : %s\n", __sym,
usymdata (strtol(__sym,16)));
__l += strlen(__line)
if (__l > @MAXSTRINGLEN) break
__foo .= __line
__sym = tokenize ("", " ")
}
return __foo
}
/**
* sfunction usymfileline - Return the file name and line number of an address.
* @addr: The address to translate.
*
* Description: Returns the file name and the (approximate) line number of the
* given address, if known. If the file name or the line number cannot be
* found, the hex string representation of the address will be returned.
*/
function usymfileline:string (addr:long) %{
/* pure */ /* myproc-unprivileged */ /* pragma:symbols */ /* pragma:vma */ /* pragma:lines */
_stp_snprint_addr(STAP_RETVALUE, MAXSTRINGLEN, STAP_ARG_addr,
_STP_SYM_LINENUMBER + _STP_SYM_FILENAME, current);
%}
/**
* sfunction usymfile - Return the file name of a given address.
* @addr: The address to translate.
*
* Description: Returns the file name of the given address, if known. If the
* file name cannot be found, the hex string representation of the address
* will be returned.
*/
function usymfile:string (addr:long) %{
/* pure */ /* myproc-unprivileged */ /* pragma:symbols */ /* pragma:vma */ /* pragma:lines */
_stp_snprint_addr(STAP_RETVALUE, MAXSTRINGLEN, STAP_ARG_addr,
_STP_SYM_FILENAME, current);
%}
/**
* sfunction usymline - Return the line number of an address.
* @addr: The address to translate.
*
* Description: Returns the (approximate) line number of the given address, if
* known. If the line number cannot be found, the hex string representation of
* the address will be returned.
*/
function usymline:string (addr:long) %{
/* pure */ /* myproc-unprivileged */ /* pragma:symbols */ /* pragma:vma */ /* pragma:lines */
_stp_snprint_addr(STAP_RETVALUE, MAXSTRINGLEN, STAP_ARG_addr,
_STP_SYM_LINENUMBER, current);
%}