1595c3649SMasami Hiramatsuperf-probe(1) 2595c3649SMasami Hiramatsu============= 3595c3649SMasami Hiramatsu 4595c3649SMasami HiramatsuNAME 5595c3649SMasami Hiramatsu---- 6595c3649SMasami Hiramatsuperf-probe - Define new dynamic tracepoints 7595c3649SMasami Hiramatsu 8595c3649SMasami HiramatsuSYNOPSIS 9595c3649SMasami Hiramatsu-------- 10595c3649SMasami Hiramatsu[verse] 11c937fe20SMasami Hiramatsu'perf probe' [options] --add='PROBE' [...] 12c43f9d1eSMasami Hiramatsuor 13c937fe20SMasami Hiramatsu'perf probe' [options] PROBE 14c937fe20SMasami Hiramatsuor 15c937fe20SMasami Hiramatsu'perf probe' [options] --del='[GROUP:]EVENT' [...] 16c937fe20SMasami Hiramatsuor 17c937fe20SMasami Hiramatsu'perf probe' --list 18631c9defSMasami Hiramatsuor 19e116dfa1SMasami Hiramatsu'perf probe' [options] --line='LINE' 20cf6eb489SMasami Hiramatsuor 21469b9b88SMasami Hiramatsu'perf probe' [options] --vars='PROBEPOINT' 22595c3649SMasami Hiramatsu 23595c3649SMasami HiramatsuDESCRIPTION 24595c3649SMasami Hiramatsu----------- 25595c3649SMasami HiramatsuThis command defines dynamic tracepoint events, by symbol and registers 26595c3649SMasami Hiramatsuwithout debuginfo, or by C expressions (C line numbers, C function names, 27595c3649SMasami Hiramatsuand C local variables) with debuginfo. 28595c3649SMasami Hiramatsu 29595c3649SMasami Hiramatsu 30595c3649SMasami HiramatsuOPTIONS 31595c3649SMasami Hiramatsu------- 32595c3649SMasami Hiramatsu-k:: 33c43f9d1eSMasami Hiramatsu--vmlinux=PATH:: 34595c3649SMasami Hiramatsu Specify vmlinux path which has debuginfo (Dwarf binary). 35595c3649SMasami Hiramatsu 36469b9b88SMasami Hiramatsu-m:: 3714a8fd7cSMasami Hiramatsu--module=MODNAME|PATH:: 38469b9b88SMasami Hiramatsu Specify module name in which perf-probe searches probe points 3914a8fd7cSMasami Hiramatsu or lines. If a path of module file is passed, perf-probe 4014a8fd7cSMasami Hiramatsu treat it as an offline module (this means you can add a probe on 4114a8fd7cSMasami Hiramatsu a module which has not been loaded yet). 42469b9b88SMasami Hiramatsu 439ed7e1b8SChase Douglas-s:: 449ed7e1b8SChase Douglas--source=PATH:: 459ed7e1b8SChase Douglas Specify path to kernel source. 469ed7e1b8SChase Douglas 47595c3649SMasami Hiramatsu-v:: 48595c3649SMasami Hiramatsu--verbose:: 49595c3649SMasami Hiramatsu Be more verbose (show parsed arguments, etc). 50595c3649SMasami Hiramatsu 51c43f9d1eSMasami Hiramatsu-a:: 52c937fe20SMasami Hiramatsu--add=:: 53c937fe20SMasami Hiramatsu Define a probe event (see PROBE SYNTAX for detail). 54c937fe20SMasami Hiramatsu 55c937fe20SMasami Hiramatsu-d:: 56c937fe20SMasami Hiramatsu--del=:: 57ee391de8SMasami Hiramatsu Delete probe events. This accepts glob wildcards('*', '?') and character 58ee391de8SMasami Hiramatsu classes(e.g. [a-z], [!A-Z]). 59c937fe20SMasami Hiramatsu 60c937fe20SMasami Hiramatsu-l:: 61c937fe20SMasami Hiramatsu--list:: 62c937fe20SMasami Hiramatsu List up current probe events. 63595c3649SMasami Hiramatsu 64631c9defSMasami Hiramatsu-L:: 65631c9defSMasami Hiramatsu--line=:: 66631c9defSMasami Hiramatsu Show source code lines which can be probed. This needs an argument 67ee391de8SMasami Hiramatsu which specifies a range of the source code. (see LINE SYNTAX for detail) 68ee391de8SMasami Hiramatsu 69cf6eb489SMasami Hiramatsu-V:: 70cf6eb489SMasami Hiramatsu--vars=:: 71cf6eb489SMasami Hiramatsu Show available local variables at given probe point. The argument 72cf6eb489SMasami Hiramatsu syntax is same as PROBE SYNTAX, but NO ARGs. 73cf6eb489SMasami Hiramatsu 74fb8c5a56SMasami Hiramatsu--externs:: 75fb8c5a56SMasami Hiramatsu (Only for --vars) Show external defined variables in addition to local 76fb8c5a56SMasami Hiramatsu variables. 77fb8c5a56SMasami Hiramatsu 78e80711caSMasami Hiramatsu-F:: 79e80711caSMasami Hiramatsu--funcs:: 80225466f1SSrikar Dronamraju Show available functions in given module or kernel. With -x/--exec, 81225466f1SSrikar Dronamraju can also list functions in a user space executable / shared library. 82e80711caSMasami Hiramatsu 83bd09d7b5SMasami Hiramatsu--filter=FILTER:: 843c42258cSMasami Hiramatsu (Only for --vars and --funcs) Set filter. FILTER is a combination of glob 853c42258cSMasami Hiramatsu pattern, see FILTER PATTERN for detail. 863c42258cSMasami Hiramatsu Default FILTER is "!__k???tab_* & !__crc_*" for --vars, and "!_*" 873c42258cSMasami Hiramatsu for --funcs. 883c42258cSMasami Hiramatsu If several filters are specified, only the last filter is used. 89bd09d7b5SMasami Hiramatsu 90ee391de8SMasami Hiramatsu-f:: 91ee391de8SMasami Hiramatsu--force:: 92ee391de8SMasami Hiramatsu Forcibly add events with existing name. 93631c9defSMasami Hiramatsu 94f4d7da49SMasami Hiramatsu-n:: 95f4d7da49SMasami Hiramatsu--dry-run:: 96f4d7da49SMasami Hiramatsu Dry run. With this option, --add and --del doesn't execute actual 97f4d7da49SMasami Hiramatsu adding and removal operations. 98f4d7da49SMasami Hiramatsu 99ef4a3565SMasami Hiramatsu--max-probes:: 100ef4a3565SMasami Hiramatsu Set the maximum number of probe points for an event. Default is 128. 101ef4a3565SMasami Hiramatsu 102225466f1SSrikar Dronamraju-x:: 103225466f1SSrikar Dronamraju--exec=PATH:: 104225466f1SSrikar Dronamraju Specify path to the executable or shared library file for user 105225466f1SSrikar Dronamraju space tracing. Can also be used with --funcs option. 106225466f1SSrikar Dronamraju 107*763122adSAvi Kivity--demangle-kernel:: 108*763122adSAvi Kivity Demangle kernel symbols. 109*763122adSAvi Kivity 11073eff9f5SSrikar DronamrajuIn absence of -m/-x options, perf probe checks if the first argument after 11173eff9f5SSrikar Dronamrajuthe options is an absolute path name. If its an absolute path, perf probe 11273eff9f5SSrikar Dronamrajuuses it as a target module/target user space binary to probe. 11373eff9f5SSrikar Dronamraju 114595c3649SMasami HiramatsuPROBE SYNTAX 115595c3649SMasami Hiramatsu------------ 116595c3649SMasami HiramatsuProbe points are defined by following syntax. 117595c3649SMasami Hiramatsu 1182a9c8c36SMasami Hiramatsu 1) Define event based on function name 1192a9c8c36SMasami Hiramatsu [EVENT=]FUNC[@SRC][:RLN|+OFFS|%return|;PTN] [ARG ...] 1202a9c8c36SMasami Hiramatsu 1212a9c8c36SMasami Hiramatsu 2) Define event based on source file with line number 1222a9c8c36SMasami Hiramatsu [EVENT=]SRC:ALN [ARG ...] 1232a9c8c36SMasami Hiramatsu 1242a9c8c36SMasami Hiramatsu 3) Define event based on source file with lazy pattern 1252a9c8c36SMasami Hiramatsu [EVENT=]SRC;PTN [ARG ...] 1262a9c8c36SMasami Hiramatsu 127595c3649SMasami Hiramatsu 128af663d75SMasami Hiramatsu'EVENT' specifies the name of new event, if omitted, it will be set the name of the probed function. Currently, event group name is set as 'probe'. 1292a9c8c36SMasami Hiramatsu'FUNC' specifies a probed function name, and it may have one of the following options; '+OFFS' is the offset from function entry address in bytes, ':RLN' is the relative-line number from function entry line, and '%return' means that it probes function return. And ';PTN' means lazy matching pattern (see LAZY MATCHING). Note that ';PTN' must be the end of the probe point definition. In addition, '@SRC' specifies a source file which has that function. 1302a9c8c36SMasami HiramatsuIt is also possible to specify a probe point by the source line number or lazy matching by using 'SRC:ALN' or 'SRC;PTN' syntax, where 'SRC' is the source file path, ':ALN' is the line number and ';PTN' is the lazy matching pattern. 13148481938SMasami Hiramatsu'ARG' specifies the arguments of this probe point, (see PROBE ARGUMENT). 13248481938SMasami Hiramatsu 13348481938SMasami HiramatsuPROBE ARGUMENT 13448481938SMasami Hiramatsu-------------- 13548481938SMasami HiramatsuEach probe argument follows below syntax. 13648481938SMasami Hiramatsu 13711a1ca35SMasami Hiramatsu [NAME=]LOCALVAR|$retval|%REG|@SYMBOL[:TYPE] 13848481938SMasami Hiramatsu 139b2a3c12bSMasami Hiramatsu'NAME' specifies the name of this argument (optional). You can use the name of local variable, local data structure member (e.g. var->field, var.field2), local array with fixed index (e.g. array[1], var->array[0], var->pointer[2]), or kprobe-tracer argument format (e.g. $retval, %ax, etc). Note that the name of this argument will be set as the last member name if you specify a local data structure member (e.g. field2 for 'var->field1.field2'.) 14073317b95SMasami Hiramatsu'TYPE' casts the type of this argument (optional). If omitted, perf probe automatically set the type based on debuginfo. You can specify 'string' type only for the local variable or structure member which is an array of or a pointer to 'char' or 'unsigned char' type. 141595c3649SMasami Hiramatsu 1425b439820SAndi KleenOn x86 systems %REG is always the short form of the register: for example %AX. %RAX or %EAX is not valid. 1435b439820SAndi Kleen 144631c9defSMasami HiramatsuLINE SYNTAX 145631c9defSMasami Hiramatsu----------- 1469d5b7f5bSShawn BohrerLine range is described by following syntax. 147631c9defSMasami Hiramatsu 148e116dfa1SMasami Hiramatsu "FUNC[@SRC][:RLN[+NUM|-RLN2]]|SRC[:ALN[+NUM|-ALN2]]" 149631c9defSMasami Hiramatsu 150631c9defSMasami HiramatsuFUNC specifies the function name of showing lines. 'RLN' is the start line 151631c9defSMasami Hiramatsunumber from function entry line, and 'RLN2' is the end line number. As same as 152631c9defSMasami Hiramatsuprobe syntax, 'SRC' means the source file path, 'ALN' is start line number, 153631c9defSMasami Hiramatsuand 'ALN2' is end line number in the file. It is also possible to specify how 154e116dfa1SMasami Hiramatsumany lines to show by using 'NUM'. Moreover, 'FUNC@SRC' combination is good 155e116dfa1SMasami Hiramatsufor searching a specific function when several functions share same name. 156631c9defSMasami HiramatsuSo, "source.c:100-120" shows lines between 100th to l20th in source.c file. And "func:10+20" shows 20 lines from 10th line of func function. 157631c9defSMasami Hiramatsu 1582a9c8c36SMasami HiramatsuLAZY MATCHING 1592a9c8c36SMasami Hiramatsu------------- 1602a9c8c36SMasami Hiramatsu The lazy line matching is similar to glob matching but ignoring spaces in both of pattern and target. So this accepts wildcards('*', '?') and character classes(e.g. [a-z], [!A-Z]). 1612a9c8c36SMasami Hiramatsu 1622a9c8c36SMasami Hiramatsue.g. 1632a9c8c36SMasami Hiramatsu 'a=*' can matches 'a=b', 'a = b', 'a == b' and so on. 1642a9c8c36SMasami Hiramatsu 1652a9c8c36SMasami HiramatsuThis provides some sort of flexibility and robustness to probe point definitions against minor code changes. For example, actual 10th line of schedule() can be moved easily by modifying schedule(), but the same line matching 'rq=cpu_rq*' may still exist in the function.) 1662a9c8c36SMasami Hiramatsu 167bd09d7b5SMasami HiramatsuFILTER PATTERN 168bd09d7b5SMasami Hiramatsu-------------- 169bd09d7b5SMasami Hiramatsu The filter pattern is a glob matching pattern(s) to filter variables. 170bd09d7b5SMasami Hiramatsu In addition, you can use "!" for specifying filter-out rule. You also can give several rules combined with "&" or "|", and fold those rules as one rule by using "(" ")". 171bd09d7b5SMasami Hiramatsu 172bd09d7b5SMasami Hiramatsue.g. 173bd09d7b5SMasami Hiramatsu With --filter "foo* | bar*", perf probe -V shows variables which start with "foo" or "bar". 174bd09d7b5SMasami Hiramatsu With --filter "!foo* & *bar", perf probe -V shows variables which don't start with "foo" and end with "bar", like "fizzbar". But "foobar" is filtered out. 1752a9c8c36SMasami Hiramatsu 176ee391de8SMasami HiramatsuEXAMPLES 177ee391de8SMasami Hiramatsu-------- 178ee391de8SMasami HiramatsuDisplay which lines in schedule() can be probed: 179ee391de8SMasami Hiramatsu 180ee391de8SMasami Hiramatsu ./perf probe --line schedule 181ee391de8SMasami Hiramatsu 182ee391de8SMasami HiramatsuAdd a probe on schedule() function 12th line with recording cpu local variable: 183ee391de8SMasami Hiramatsu 184ee391de8SMasami Hiramatsu ./perf probe schedule:12 cpu 185ee391de8SMasami Hiramatsu or 186ee391de8SMasami Hiramatsu ./perf probe --add='schedule:12 cpu' 187ee391de8SMasami Hiramatsu 188ee391de8SMasami Hiramatsu this will add one or more probes which has the name start with "schedule". 189ee391de8SMasami Hiramatsu 1902a9c8c36SMasami Hiramatsu Add probes on lines in schedule() function which calls update_rq_clock(). 1912a9c8c36SMasami Hiramatsu 1922a9c8c36SMasami Hiramatsu ./perf probe 'schedule;update_rq_clock*' 1932a9c8c36SMasami Hiramatsu or 1942a9c8c36SMasami Hiramatsu ./perf probe --add='schedule;update_rq_clock*' 1952a9c8c36SMasami Hiramatsu 196ee391de8SMasami HiramatsuDelete all probes on schedule(). 197ee391de8SMasami Hiramatsu 198ee391de8SMasami Hiramatsu ./perf probe --del='schedule*' 199ee391de8SMasami Hiramatsu 200225466f1SSrikar DronamrajuAdd probes at zfree() function on /bin/zsh 201225466f1SSrikar Dronamraju 20273eff9f5SSrikar Dronamraju ./perf probe -x /bin/zsh zfree or ./perf probe /bin/zsh zfree 203225466f1SSrikar Dronamraju 204225466f1SSrikar DronamrajuAdd probes at malloc() function on libc 205225466f1SSrikar Dronamraju 20673eff9f5SSrikar Dronamraju ./perf probe -x /lib/libc.so.6 malloc or ./perf probe /lib/libc.so.6 malloc 207ee391de8SMasami Hiramatsu 208595c3649SMasami HiramatsuSEE ALSO 209595c3649SMasami Hiramatsu-------- 210595c3649SMasami Hiramatsulinkperf:perf-trace[1], linkperf:perf-record[1] 211