linux_dsm_epyc7002/tools/perf/Documentation/perf-script.txt
Adrian Hunter e216708d98 perf script: Add callindent option
Based on patches from Andi Kleen.

When printing PT instruction traces with perf script it is rather useful
to see some indentation for the call tree. This patch adds a new
callindent field to perf script that prints spaces for the function call
stack depth.

We already have code to track the function call stack for PT, that we
can reuse with minor modifications.

The resulting output is not quite as nice as ftrace yet, but a lot
better than what was there before.

Note there are some corner cases when the thread stack gets code
confused and prints incorrect indentation. Even with that it is fairly
useful.

When displaying kernel code traces it is recommended to run as root, as
otherwise perf doesn't understand the kernel addresses properly, and may
not reset the call stack correctly on kernel boundaries.

Example output:

	sudo perf-with-kcore record eg2 -a -e intel_pt// -- sleep 1
	sudo perf-with-kcore script eg2 --ns -F callindent,time,comm,pid,sym,ip,addr,flags,cpu --itrace=cre | less
	...
         swapper     0 [000]  5830.389116586:   call        irq_exit                                                     ffffffff8104d620 smp_call_function_single_interrupt+0x30 => ffffffff8107e720 irq_exit
         swapper     0 [000]  5830.389116586:   call            idle_cpu                                                 ffffffff8107e769 irq_exit+0x49 => ffffffff810a3970 idle_cpu
         swapper     0 [000]  5830.389116586:   return          idle_cpu                                                 ffffffff810a39b7 idle_cpu+0x47 => ffffffff8107e76e irq_exit
         swapper     0 [000]  5830.389116586:   call            tick_nohz_irq_exit                                       ffffffff8107e7bd irq_exit+0x9d => ffffffff810f2fc0 tick_nohz_irq_exit
         swapper     0 [000]  5830.389116919:   call                __tick_nohz_idle_enter                               ffffffff810f2fe0 tick_nohz_irq_exit+0x20 => ffffffff810f28d0 __tick_nohz_idle_enter
         swapper     0 [000]  5830.389116919:   call                    ktime_get                                        ffffffff810f28f1 __tick_nohz_idle_enter+0x21 => ffffffff810e9ec0 ktime_get
         swapper     0 [000]  5830.389116919:   call                        read_tsc                                     ffffffff810e9ef6 ktime_get+0x36 => ffffffff81035070 read_tsc
         swapper     0 [000]  5830.389116919:   return                      read_tsc                                     ffffffff81035084 read_tsc+0x14 => ffffffff810e9efc ktime_get
         swapper     0 [000]  5830.389116919:   return                  ktime_get                                        ffffffff810e9f46 ktime_get+0x86 => ffffffff810f28f6 __tick_nohz_idle_enter
         swapper     0 [000]  5830.389116919:   call                    sched_clock_idle_sleep_event                     ffffffff810f290b __tick_nohz_idle_enter+0x3b => ffffffff810a7380 sched_clock_idle_sleep_event
         swapper     0 [000]  5830.389116919:   call                        sched_clock_cpu                              ffffffff810a738b sched_clock_idle_sleep_event+0xb => ffffffff810a72e0 sched_clock_cpu
         swapper     0 [000]  5830.389116919:   call                            sched_clock                              ffffffff810a734d sched_clock_cpu+0x6d => ffffffff81035750 sched_clock
         swapper     0 [000]  5830.389116919:   call                                native_sched_clock                   ffffffff81035754 sched_clock+0x4 => ffffffff81035640 native_sched_clock
         swapper     0 [000]  5830.389116919:   return                              native_sched_clock                   ffffffff8103568c native_sched_clock+0x4c => ffffffff81035759 sched_clock
         swapper     0 [000]  5830.389116919:   return                          sched_clock                              ffffffff8103575c sched_clock+0xc => ffffffff810a7352 sched_clock_cpu
         swapper     0 [000]  5830.389116919:   return                      sched_clock_cpu                              ffffffff810a7356 sched_clock_cpu+0x76 => ffffffff810a7390 sched_clock_idle_sleep_event
         swapper     0 [000]  5830.389116919:   return                  sched_clock_idle_sleep_event                     ffffffff810a7391 sched_clock_idle_sleep_event+0x11 => ffffffff810f2910 __tick_nohz_idle_enter
	...

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1466689258-28493-4-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-06-23 17:04:26 -03:00

292 lines
10 KiB
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perf-script(1)
=============
NAME
----
perf-script - Read perf.data (created by perf record) and display trace output
SYNOPSIS
--------
[verse]
'perf script' [<options>]
'perf script' [<options>] record <script> [<record-options>] <command>
'perf script' [<options>] report <script> [script-args]
'perf script' [<options>] <script> <required-script-args> [<record-options>] <command>
'perf script' [<options>] <top-script> [script-args]
DESCRIPTION
-----------
This command reads the input file and displays the trace recorded.
There are several variants of perf script:
'perf script' to see a detailed trace of the workload that was
recorded.
You can also run a set of pre-canned scripts that aggregate and
summarize the raw trace data in various ways (the list of scripts is
available via 'perf script -l'). The following variants allow you to
record and run those scripts:
'perf script record <script> <command>' to record the events required
for 'perf script report'. <script> is the name displayed in the
output of 'perf script --list' i.e. the actual script name minus any
language extension. If <command> is not specified, the events are
recorded using the -a (system-wide) 'perf record' option.
'perf script report <script> [args]' to run and display the results
of <script>. <script> is the name displayed in the output of 'perf
trace --list' i.e. the actual script name minus any language
extension. The perf.data output from a previous run of 'perf script
record <script>' is used and should be present for this command to
succeed. [args] refers to the (mainly optional) args expected by
the script.
'perf script <script> <required-script-args> <command>' to both
record the events required for <script> and to run the <script>
using 'live-mode' i.e. without writing anything to disk. <script>
is the name displayed in the output of 'perf script --list' i.e. the
actual script name minus any language extension. If <command> is
not specified, the events are recorded using the -a (system-wide)
'perf record' option. If <script> has any required args, they
should be specified before <command>. This mode doesn't allow for
optional script args to be specified; if optional script args are
desired, they can be specified using separate 'perf script record'
and 'perf script report' commands, with the stdout of the record step
piped to the stdin of the report script, using the '-o -' and '-i -'
options of the corresponding commands.
'perf script <top-script>' to both record the events required for
<top-script> and to run the <top-script> using 'live-mode'
i.e. without writing anything to disk. <top-script> is the name
displayed in the output of 'perf script --list' i.e. the actual
script name minus any language extension; a <top-script> is defined
as any script name ending with the string 'top'.
[<record-options>] can be passed to the record steps of 'perf script
record' and 'live-mode' variants; this isn't possible however for
<top-script> 'live-mode' or 'perf script report' variants.
See the 'SEE ALSO' section for links to language-specific
information on how to write and run your own trace scripts.
OPTIONS
-------
<command>...::
Any command you can specify in a shell.
-D::
--dump-raw-script=::
Display verbose dump of the trace data.
-L::
--Latency=::
Show latency attributes (irqs/preemption disabled, etc).
-l::
--list=::
Display a list of available trace scripts.
-s ['lang']::
--script=::
Process trace data with the given script ([lang]:script[.ext]).
If the string 'lang' is specified in place of a script name, a
list of supported languages will be displayed instead.
-g::
--gen-script=::
Generate perf-script.[ext] starter script for given language,
using current perf.data.
-a::
Force system-wide collection. Scripts run without a <command>
normally use -a by default, while scripts run with a <command>
normally don't - this option allows the latter to be run in
system-wide mode.
-i::
--input=::
Input file name. (default: perf.data unless stdin is a fifo)
-d::
--debug-mode::
Do various checks like samples ordering and lost events.
-F::
--fields::
Comma separated list of fields to print. Options are:
comm, tid, pid, time, cpu, event, trace, ip, sym, dso, addr, symoff,
srcline, period, iregs, brstack, brstacksym, flags.
Field list can be prepended with the type, trace, sw or hw,
to indicate to which event type the field list applies.
e.g., -F sw:comm,tid,time,ip,sym and -F trace:time,cpu,trace
perf script -F <fields>
is equivalent to:
perf script -F trace:<fields> -F sw:<fields> -F hw:<fields>
i.e., the specified fields apply to all event types if the type string
is not given.
The arguments are processed in the order received. A later usage can
reset a prior request. e.g.:
-F trace: -F comm,tid,time,ip,sym
The first -F suppresses trace events (field list is ""), but then the
second invocation sets the fields to comm,tid,time,ip,sym. In this case a
warning is given to the user:
"Overriding previous field request for all events."
Alternatively, consider the order:
-F comm,tid,time,ip,sym -F trace:
The first -F sets the fields for all events and the second -F
suppresses trace events. The user is given a warning message about
the override, and the result of the above is that only S/W and H/W
events are displayed with the given fields.
For the 'wildcard' option if a user selected field is invalid for an
event type, a message is displayed to the user that the option is
ignored for that type. For example:
$ perf script -F comm,tid,trace
'trace' not valid for hardware events. Ignoring.
'trace' not valid for software events. Ignoring.
Alternatively, if the type is given an invalid field is specified it
is an error. For example:
perf script -v -F sw:comm,tid,trace
'trace' not valid for software events.
At this point usage is displayed, and perf-script exits.
The flags field is synthesized and may have a value when Instruction
Trace decoding. The flags are "bcrosyiABEx" which stand for branch,
call, return, conditional, system, asynchronous, interrupt,
transaction abort, trace begin, trace end, and in transaction,
respectively. Known combinations of flags are printed more nicely e.g.
"call" for "bc", "return" for "br", "jcc" for "bo", "jmp" for "b",
"int" for "bci", "iret" for "bri", "syscall" for "bcs", "sysret" for "brs",
"async" for "by", "hw int" for "bcyi", "tx abrt" for "bA", "tr strt" for "bB",
"tr end" for "bE". However the "x" flag will be display separately in those
cases e.g. "jcc (x)" for a condition branch within a transaction.
The callindent field is synthesized and may have a value when
Instruction Trace decoding. For calls and returns, it will display the
name of the symbol indented with spaces to reflect the stack depth.
Finally, a user may not set fields to none for all event types.
i.e., -F "" is not allowed.
The brstack output includes branch related information with raw addresses using the
/v/v/v/v/ syntax in the following order:
FROM: branch source instruction
TO : branch target instruction
M/P/-: M=branch target mispredicted or branch direction was mispredicted, P=target predicted or direction predicted, -=not supported
X/- : X=branch inside a transactional region, -=not in transaction region or not supported
A/- : A=TSX abort entry, -=not aborted region or not supported
The brstacksym is identical to brstack, except that the FROM and TO addresses are printed in a symbolic form if possible.
-k::
--vmlinux=<file>::
vmlinux pathname
--kallsyms=<file>::
kallsyms pathname
--symfs=<directory>::
Look for files with symbols relative to this directory.
-G::
--hide-call-graph::
When printing symbols do not display call chain.
-C::
--cpu:: Only report samples for the list of CPUs provided. Multiple CPUs can
be provided as a comma-separated list with no space: 0,1. Ranges of
CPUs are specified with -: 0-2. Default is to report samples on all
CPUs.
-c::
--comms=::
Only display events for these comms. CSV that understands
file://filename entries.
--pid=::
Only show events for given process ID (comma separated list).
--tid=::
Only show events for given thread ID (comma separated list).
-I::
--show-info::
Display extended information about the perf.data file. This adds
information which may be very large and thus may clutter the display.
It currently includes: cpu and numa topology of the host system.
It can only be used with the perf script report mode.
--show-kernel-path::
Try to resolve the path of [kernel.kallsyms]
--show-task-events
Display task related events (e.g. FORK, COMM, EXIT).
--show-mmap-events
Display mmap related events (e.g. MMAP, MMAP2).
--show-switch-events
Display context switch events i.e. events of type PERF_RECORD_SWITCH or
PERF_RECORD_SWITCH_CPU_WIDE.
--demangle::
Demangle symbol names to human readable form. It's enabled by default,
disable with --no-demangle.
--demangle-kernel::
Demangle kernel symbol names to human readable form (for C++ kernels).
--header
Show perf.data header.
--header-only
Show only perf.data header.
--itrace::
Options for decoding instruction tracing data. The options are:
include::itrace.txt[]
To disable decoding entirely, use --no-itrace.
--full-source-path::
Show the full path for source files for srcline output.
--max-stack::
Set the stack depth limit when parsing the callchain, anything
beyond the specified depth will be ignored. This is a trade-off
between information loss and faster processing especially for
workloads that can have a very long callchain stack.
Note that when using the --itrace option the synthesized callchain size
will override this value if the synthesized callchain size is bigger.
Default: 127
--ns::
Use 9 decimal places when displaying time (i.e. show the nanoseconds)
-f::
--force::
Don't do ownership validation.
SEE ALSO
--------
linkperf:perf-record[1], linkperf:perf-script-perl[1],
linkperf:perf-script-python[1]