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diff --git a/tools/perf/Documentation/perf-config.txt b/tools/perf/Documentation/perf-config.txt new file mode 100644 index 000000000..39c890ead --- /dev/null +++ b/tools/perf/Documentation/perf-config.txt @@ -0,0 +1,755 @@ +perf-config(1) +============== + +NAME +---- +perf-config - Get and set variables in a configuration file. + +SYNOPSIS +-------- +[verse] +'perf config' [<file-option>] [section.name[=value] ...] +or +'perf config' [<file-option>] -l | --list + +DESCRIPTION +----------- +You can manage variables in a configuration file with this command. + +OPTIONS +------- + +-l:: +--list:: + Show current config variables, name and value, for all sections. + +--user:: + For writing and reading options: write to user + '$HOME/.perfconfig' file or read it. + +--system:: + For writing and reading options: write to system-wide + '$(sysconfdir)/perfconfig' or read it. + +CONFIGURATION FILE +------------------ + +The perf configuration file contains many variables to change various +aspects of each of its tools, including output, disk usage, etc. +The '$HOME/.perfconfig' file is used to store a per-user configuration. +The file '$(sysconfdir)/perfconfig' can be used to +store a system-wide default configuration. + +One an disable reading config files by setting the PERF_CONFIG environment +variable to /dev/null, or provide an alternate config file by setting that +variable. + +When reading or writing, the values are read from the system and user +configuration files by default, and options '--system' and '--user' +can be used to tell the command to read from or write to only that location. + +Syntax +~~~~~~ + +The file consist of sections. A section starts with its name +surrounded by square brackets and continues till the next section +begins. Each variable must be in a section, and have the form +'name = value', for example: + + [section] + name1 = value1 + name2 = value2 + +Section names are case sensitive and can contain any characters except +newline (double quote `"` and backslash have to be escaped as `\"` and `\\`, +respectively). Section headers can't span multiple lines. + +Example +~~~~~~~ + +Given a $HOME/.perfconfig like this: + +# +# This is the config file, and +# a '#' and ';' character indicates a comment +# + + [colors] + # Color variables + top = red, default + medium = green, default + normal = lightgray, default + selected = white, lightgray + jump_arrows = blue, default + addr = magenta, default + root = white, blue + + [tui] + # Defaults if linked with libslang + report = on + annotate = on + top = on + + [buildid] + # Default, disable using /dev/null + dir = ~/.debug + + [annotate] + # Defaults + hide_src_code = false + use_offset = true + jump_arrows = true + show_nr_jumps = false + + [help] + # Format can be man, info, web or html + format = man + autocorrect = 0 + + [ui] + show-headers = true + + [call-graph] + # fp (framepointer), dwarf + record-mode = fp + print-type = graph + order = caller + sort-key = function + + [report] + # Defaults + sort_order = comm,dso,symbol + percent-limit = 0 + queue-size = 0 + children = true + group = true + skip-empty = true + + [llvm] + dump-obj = true + clang-opt = -g + +You can hide source code of annotate feature setting the config to false with + + % perf config annotate.hide_src_code=true + +If you want to add or modify several config items, you can do like + + % perf config ui.show-headers=false kmem.default=slab + +To modify the sort order of report functionality in user config file(i.e. `~/.perfconfig`), do + + % perf config --user report.sort-order=srcline + +To change colors of selected line to other foreground and background colors +in system config file (i.e. `$(sysconf)/perfconfig`), do + + % perf config --system colors.selected=yellow,green + +To query the record mode of call graph, do + + % perf config call-graph.record-mode + +If you want to know multiple config key/value pairs, you can do like + + % perf config report.queue-size call-graph.order report.children + +To query the config value of sort order of call graph in user config file (i.e. `~/.perfconfig`), do + + % perf config --user call-graph.sort-order + +To query the config value of buildid directory in system config file (i.e. `$(sysconf)/perfconfig`), do + + % perf config --system buildid.dir + +Variables +~~~~~~~~~ + +colors.*:: + The variables for customizing the colors used in the output for the + 'report', 'top' and 'annotate' in the TUI. They should specify the + foreground and background colors, separated by a comma, for example: + + medium = green, lightgray + + If you want to use the color configured for you terminal, just leave it + as 'default', for example: + + medium = default, lightgray + + Available colors: + red, yellow, green, cyan, gray, black, blue, + white, default, magenta, lightgray + + colors.top:: + 'top' means a overhead percentage which is more than 5%. + And values of this variable specify percentage colors. + Basic key values are foreground-color 'red' and + background-color 'default'. + colors.medium:: + 'medium' means a overhead percentage which has more than 0.5%. + Default values are 'green' and 'default'. + colors.normal:: + 'normal' means the rest of overhead percentages + except 'top', 'medium', 'selected'. + Default values are 'lightgray' and 'default'. + colors.selected:: + This selects the colors for the current entry in a list of entries + from sub-commands (top, report, annotate). + Default values are 'black' and 'lightgray'. + colors.jump_arrows:: + Colors for jump arrows on assembly code listings + such as 'jns', 'jmp', 'jane', etc. + Default values are 'blue', 'default'. + colors.addr:: + This selects colors for addresses from 'annotate'. + Default values are 'magenta', 'default'. + colors.root:: + Colors for headers in the output of a sub-commands (top, report). + Default values are 'white', 'blue'. + +core.*:: + core.proc-map-timeout:: + Sets a timeout (in milliseconds) for parsing /proc/<pid>/maps files. + Can be overridden by the --proc-map-timeout option on supported + subcommands. The default timeout is 500ms. + +tui.*, gtk.*:: + Subcommands that can be configured here are 'top', 'report' and 'annotate'. + These values are booleans, for example: + + [tui] + top = true + + will make the TUI be the default for the 'top' subcommand. Those will be + available if the required libs were detected at tool build time. + +buildid.*:: + buildid.dir:: + Each executable and shared library in modern distributions comes with a + content based identifier that, if available, will be inserted in a + 'perf.data' file header to, at analysis time find what is needed to do + symbol resolution, code annotation, etc. + + The recording tools also stores a hard link or copy in a per-user + directory, $HOME/.debug/, of binaries, shared libraries, /proc/kallsyms + and /proc/kcore files to be used at analysis time. + + The buildid.dir variable can be used to either change this directory + cache location, or to disable it altogether. If you want to disable it, + set buildid.dir to /dev/null. The default is $HOME/.debug + +buildid-cache.*:: + buildid-cache.debuginfod=URLs + Specify debuginfod URLs to be used when retrieving perf.data binaries, + it follows the same syntax as the DEBUGINFOD_URLS variable, like: + + buildid-cache.debuginfod=http://192.168.122.174:8002 + +annotate.*:: + These are in control of addresses, jump function, source code + in lines of assembly code from a specific program. + + annotate.disassembler_style: + Use this to change the default disassembler style to some other value + supported by binutils, such as "intel", see the '-M' option help in the + 'objdump' man page. + + annotate.hide_src_code:: + If a program which is analyzed has source code, + this option lets 'annotate' print a list of assembly code with the source code. + For example, let's see a part of a program. There're four lines. + If this option is 'true', they can be printed + without source code from a program as below. + + │ push %rbp + │ mov %rsp,%rbp + │ sub $0x10,%rsp + │ mov (%rdi),%rdx + + But if this option is 'false', source code of the part + can be also printed as below. Default is 'false'. + + │ struct rb_node *rb_next(const struct rb_node *node) + │ { + │ push %rbp + │ mov %rsp,%rbp + │ sub $0x10,%rsp + │ struct rb_node *parent; + │ + │ if (RB_EMPTY_NODE(node)) + │ mov (%rdi),%rdx + │ return n; + + This option works with tui, stdio2 browsers. + + annotate.use_offset:: + Basing on a first address of a loaded function, offset can be used. + Instead of using original addresses of assembly code, + addresses subtracted from a base address can be printed. + Let's illustrate an example. + If a base address is 0XFFFFFFFF81624d50 as below, + + ffffffff81624d50 <load0> + + an address on assembly code has a specific absolute address as below + + ffffffff816250b8:│ mov 0x8(%r14),%rdi + + but if use_offset is 'true', an address subtracted from a base address is printed. + Default is true. This option is only applied to TUI. + + 368:│ mov 0x8(%r14),%rdi + + This option works with tui, stdio2 browsers. + + annotate.jump_arrows:: + There can be jump instruction among assembly code. + Depending on a boolean value of jump_arrows, + arrows can be printed or not which represent + where do the instruction jump into as below. + + │ ┌──jmp 1333 + │ │ xchg %ax,%ax + │1330:│ mov %r15,%r10 + │1333:└─→cmp %r15,%r14 + + If jump_arrow is 'false', the arrows isn't printed as below. + Default is 'false'. + + │ ↓ jmp 1333 + │ xchg %ax,%ax + │1330: mov %r15,%r10 + │1333: cmp %r15,%r14 + + This option works with tui browser. + + annotate.show_linenr:: + When showing source code if this option is 'true', + line numbers are printed as below. + + │1628 if (type & PERF_SAMPLE_IDENTIFIER) { + │ ↓ jne 508 + │1628 data->id = *array; + │1629 array++; + │1630 } + + However if this option is 'false', they aren't printed as below. + Default is 'false'. + + │ if (type & PERF_SAMPLE_IDENTIFIER) { + │ ↓ jne 508 + │ data->id = *array; + │ array++; + │ } + + This option works with tui, stdio2 browsers. + + annotate.show_nr_jumps:: + Let's see a part of assembly code. + + │1382: movb $0x1,-0x270(%rbp) + + If use this, the number of branches jumping to that address can be printed as below. + Default is 'false'. + + │1 1382: movb $0x1,-0x270(%rbp) + + This option works with tui, stdio2 browsers. + + annotate.show_total_period:: + To compare two records on an instruction base, with this option + provided, display total number of samples that belong to a line + in assembly code. If this option is 'true', total periods are printed + instead of percent values as below. + + 302 │ mov %eax,%eax + + But if this option is 'false', percent values for overhead are printed i.e. + Default is 'false'. + + 99.93 │ mov %eax,%eax + + This option works with tui, stdio2, stdio browsers. + + annotate.show_nr_samples:: + By default perf annotate shows percentage of samples. This option + can be used to print absolute number of samples. Ex, when set as + false: + + Percent│ + 74.03 │ mov %fs:0x28,%rax + + When set as true: + + Samples│ + 6 │ mov %fs:0x28,%rax + + This option works with tui, stdio2, stdio browsers. + + annotate.offset_level:: + Default is '1', meaning just jump targets will have offsets show right beside + the instruction. When set to '2' 'call' instructions will also have its offsets + shown, 3 or higher will show offsets for all instructions. + + This option works with tui, stdio2 browsers. + + annotate.demangle:: + Demangle symbol names to human readable form. Default is 'true'. + + annotate.demangle_kernel:: + Demangle kernel symbol names to human readable form. Default is 'true'. + +hist.*:: + hist.percentage:: + This option control the way to calculate overhead of filtered entries - + that means the value of this option is effective only if there's a + filter (by comm, dso or symbol name). Suppose a following example: + + Overhead Symbols + ........ ....... + 33.33% foo + 33.33% bar + 33.33% baz + + This is an original overhead and we'll filter out the first 'foo' + entry. The value of 'relative' would increase the overhead of 'bar' + and 'baz' to 50.00% for each, while 'absolute' would show their + current overhead (33.33%). + +ui.*:: + ui.show-headers:: + This option controls display of column headers (like 'Overhead' and 'Symbol') + in 'report' and 'top'. If this option is false, they are hidden. + This option is only applied to TUI. + +call-graph.*:: + The following controls the handling of call-graphs (obtained via the + -g/--call-graph options). + + call-graph.record-mode:: + The mode for user space can be 'fp' (frame pointer), 'dwarf' + and 'lbr'. The value 'dwarf' is effective only if libunwind + (or a recent version of libdw) is present on the system; + the value 'lbr' only works for certain cpus. The method for + kernel space is controlled not by this option but by the + kernel config (CONFIG_UNWINDER_*). + + call-graph.dump-size:: + The size of stack to dump in order to do post-unwinding. Default is 8192 (byte). + When using dwarf into record-mode, the default size will be used if omitted. + + call-graph.print-type:: + The print-types can be graph (graph absolute), fractal (graph relative), + flat and folded. This option controls a way to show overhead for each callchain + entry. Suppose a following example. + + Overhead Symbols + ........ ....... + 40.00% foo + | + ---foo + | + |--50.00%--bar + | main + | + --50.00%--baz + main + + This output is a 'fractal' format. The 'foo' came from 'bar' and 'baz' exactly + half and half so 'fractal' shows 50.00% for each + (meaning that it assumes 100% total overhead of 'foo'). + + The 'graph' uses absolute overhead value of 'foo' as total so each of + 'bar' and 'baz' callchain will have 20.00% of overhead. + If 'flat' is used, single column and linear exposure of call chains. + 'folded' mean call chains are displayed in a line, separated by semicolons. + + call-graph.order:: + This option controls print order of callchains. The default is + 'callee' which means callee is printed at top and then followed by its + caller and so on. The 'caller' prints it in reverse order. + + If this option is not set and report.children or top.children is + set to true (or the equivalent command line option is given), + the default value of this option is changed to 'caller' for the + execution of 'perf report' or 'perf top'. Other commands will + still default to 'callee'. + + call-graph.sort-key:: + The callchains are merged if they contain same information. + The sort-key option determines a way to compare the callchains. + A value of 'sort-key' can be 'function' or 'address'. + The default is 'function'. + + call-graph.threshold:: + When there're many callchains it'd print tons of lines. So perf omits + small callchains under a certain overhead (threshold) and this option + control the threshold. Default is 0.5 (%). The overhead is calculated + by value depends on call-graph.print-type. + + call-graph.print-limit:: + This is a maximum number of lines of callchain printed for a single + histogram entry. Default is 0 which means no limitation. + +report.*:: + report.sort_order:: + Allows changing the default sort order from "comm,dso,symbol" to + some other default, for instance "sym,dso" may be more fitting for + kernel developers. + report.percent-limit:: + This one is mostly the same as call-graph.threshold but works for + histogram entries. Entries having an overhead lower than this + percentage will not be printed. Default is '0'. If percent-limit + is '10', only entries which have more than 10% of overhead will be + printed. + + report.queue-size:: + This option sets up the maximum allocation size of the internal + event queue for ordering events. Default is 0, meaning no limit. + + report.children:: + 'Children' means functions called from another function. + If this option is true, 'perf report' cumulates callchains of children + and show (accumulated) total overhead as well as 'Self' overhead. + Please refer to the 'perf report' manual. The default is 'true'. + + report.group:: + This option is to show event group information together. + Example output with this turned on, notice that there is one column + per event in the group, ref-cycles and cycles: + + # group: {ref-cycles,cycles} + # ======== + # + # Samples: 7K of event 'anon group { ref-cycles, cycles }' + # Event count (approx.): 6876107743 + # + # Overhead Command Shared Object Symbol + # ................ ....... ................. ................... + # + 99.84% 99.76% noploop noploop [.] main + 0.07% 0.00% noploop ld-2.15.so [.] strcmp + 0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del + + report.skip-empty:: + This option can change default stat behavior with empty results. + If it's set true, 'perf report --stat' will not show 0 stats. + +top.*:: + top.children:: + Same as 'report.children'. So if it is enabled, the output of 'top' + command will have 'Children' overhead column as well as 'Self' overhead + column by default. + The default is 'true'. + + top.call-graph:: + This is identical to 'call-graph.record-mode', except it is + applicable only for 'top' subcommand. This option ONLY setup + the unwind method. To enable 'perf top' to actually use it, + the command line option -g must be specified. + +man.*:: + man.viewer:: + This option can assign a tool to view manual pages when 'help' + subcommand was invoked. Supported tools are 'man', 'woman' + (with emacs client) and 'konqueror'. Default is 'man'. + + New man viewer tool can be also added using 'man.<tool>.cmd' + or use different path using 'man.<tool>.path' config option. + +pager.*:: + pager.<subcommand>:: + When the subcommand is run on stdio, determine whether it uses + pager or not based on this value. Default is 'unspecified'. + +kmem.*:: + kmem.default:: + This option decides which allocator is to be analyzed if neither + '--slab' nor '--page' option is used. Default is 'slab'. + +record.*:: + record.build-id:: + This option can be 'cache', 'no-cache', 'skip' or 'mmap'. + 'cache' is to post-process data and save/update the binaries into + the build-id cache (in ~/.debug). This is the default. + But if this option is 'no-cache', it will not update the build-id cache. + 'skip' skips post-processing and does not update the cache. + 'mmap' skips post-processing and reads build-ids from MMAP events. + + record.call-graph:: + This is identical to 'call-graph.record-mode', except it is + applicable only for 'record' subcommand. This option ONLY setup + the unwind method. To enable 'perf record' to actually use it, + the command line option -g must be specified. + + record.aio:: + Use 'n' control blocks in asynchronous (Posix AIO) trace writing + mode ('n' default: 1, max: 4). + + record.debuginfod:: + Specify debuginfod URL to be used when cacheing perf.data binaries, + it follows the same syntax as the DEBUGINFOD_URLS variable, like: + + http://192.168.122.174:8002 + + If the URLs is 'system', the value of DEBUGINFOD_URLS system environment + variable is used. + +diff.*:: + diff.order:: + This option sets the number of columns to sort the result. + The default is 0, which means sorting by baseline. + Setting it to 1 will sort the result by delta (or other + compute method selected). + + diff.compute:: + This options sets the method for computing the diff result. + Possible values are 'delta', 'delta-abs', 'ratio' and + 'wdiff'. Default is 'delta'. + +trace.*:: + trace.add_events:: + Allows adding a set of events to add to the ones specified + by the user, or use as a default one if none was specified. + The initial use case is to add augmented_raw_syscalls.o to + activate the 'perf trace' logic that looks for syscall + pointer contents after the normal tracepoint payload. + + trace.args_alignment:: + Number of columns to align the argument list, default is 70, + use 40 for the strace default, zero to no alignment. + + trace.no_inherit:: + Do not follow children threads. + + trace.show_arg_names:: + Should syscall argument names be printed? If not then trace.show_zeros + will be set. + + trace.show_duration:: + Show syscall duration. + + trace.show_prefix:: + If set to 'yes' will show common string prefixes in tables. The default + is to remove the common prefix in things like "MAP_SHARED", showing just "SHARED". + + trace.show_timestamp:: + Show syscall start timestamp. + + trace.show_zeros:: + Do not suppress syscall arguments that are equal to zero. + + trace.tracepoint_beautifiers:: + Use "libtraceevent" to use that library to augment the tracepoint arguments, + "libbeauty", the default, to use the same argument beautifiers used in the + strace-like sys_enter+sys_exit lines. + +ftrace.*:: + ftrace.tracer:: + Can be used to select the default tracer when neither -G nor + -F option is not specified. Possible values are 'function' and + 'function_graph'. + +llvm.*:: + llvm.clang-path:: + Path to clang. If omit, search it from $PATH. + + llvm.clang-bpf-cmd-template:: + Cmdline template. Below lines show its default value. Environment + variable is used to pass options. + "$CLANG_EXEC -D__KERNEL__ -D__NR_CPUS__=$NR_CPUS "\ + "-DLINUX_VERSION_CODE=$LINUX_VERSION_CODE " \ + "$CLANG_OPTIONS $PERF_BPF_INC_OPTIONS $KERNEL_INC_OPTIONS " \ + "-Wno-unused-value -Wno-pointer-sign " \ + "-working-directory $WORKING_DIR " \ + "-c \"$CLANG_SOURCE\" -target bpf $CLANG_EMIT_LLVM -O2 -o - $LLVM_OPTIONS_PIPE" + + llvm.clang-opt:: + Options passed to clang. + + llvm.kbuild-dir:: + kbuild directory. If not set, use /lib/modules/`uname -r`/build. + If set to "" deliberately, skip kernel header auto-detector. + + llvm.kbuild-opts:: + Options passed to 'make' when detecting kernel header options. + + llvm.dump-obj:: + Enable perf dump BPF object files compiled by LLVM. + + llvm.opts:: + Options passed to llc. + +samples.*:: + + samples.context:: + Define how many ns worth of time to show + around samples in perf report sample context browser. + +scripts.*:: + + Any option defines a script that is added to the scripts menu + in the interactive perf browser and whose output is displayed. + The name of the option is the name, the value is a script command line. + The script gets the same options passed as a full perf script, + in particular -i perfdata file, --cpu, --tid + +convert.*:: + + convert.queue-size:: + Limit the size of ordered_events queue, so we could control + allocation size of perf data files without proper finished + round events. +stat.*:: + + stat.big-num:: + (boolean) Change the default for "--big-num". To make + "--no-big-num" the default, set "stat.big-num=false". + +intel-pt.*:: + + intel-pt.cache-divisor:: + + intel-pt.mispred-all:: + If set, Intel PT decoder will set the mispred flag on all + branches. + + intel-pt.max-loops:: + If set and non-zero, the maximum number of unconditional + branches decoded without consuming any trace packets. If + the maximum is exceeded there will be a "Never-ending loop" + error. The default is 100000. + +auxtrace.*:: + + auxtrace.dumpdir:: + s390 only. The directory to save the auxiliary trace buffer + can be changed using this option. Ex, auxtrace.dumpdir=/tmp. + If the directory does not exist or has the wrong file type, + the current directory is used. + +itrace.*:: + + debug-log-buffer-size:: + Log size in bytes to output when using the option --itrace=d+e + Refer 'itrace' option of linkperf:perf-script[1] or + linkperf:perf-report[1]. The default is 16384. + +daemon.*:: + + daemon.base:: + Base path for daemon data. All sessions data are stored under + this path. + +session-<NAME>.*:: + + session-<NAME>.run:: + + Defines new record session for daemon. The value is record's + command line without the 'record' keyword. + + +SEE ALSO +-------- +linkperf:perf[1] |