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perf-list(1)
============

NAME
----
perf-list - List all symbolic event types

SYNOPSIS
--------
[verse]
'perf list' [hw|sw|cache|tracepoint|pmu|event_glob]

DESCRIPTION
-----------
This command displays the symbolic event types which can be selected in the
various perf commands with the -e option.

[[EVENT_MODIFIERS]]
EVENT MODIFIERS
---------------

Events can optionally have a modifier by appending a colon and one or
more modifiers. Modifiers allow the user to restrict the events to be
counted. The following modifiers exist:

 u - user-space counting
 k - kernel counting
 h - hypervisor counting
 I - non idle counting
 G - guest counting (in KVM guests)
 H - host counting (not in KVM guests)
 p - precise level
 P - use maximum detected precise level
 S - read sample value (PERF_SAMPLE_READ)
 D - pin the event to the PMU

The 'p' modifier can be used for specifying how precise the instruction
address should be. The 'p' modifier can be specified multiple times:

 0 - SAMPLE_IP can have arbitrary skid
 1 - SAMPLE_IP must have constant skid
 2 - SAMPLE_IP requested to have 0 skid
 3 - SAMPLE_IP must have 0 skid

For Intel systems precise event sampling is implemented with PEBS
which supports up to precise-level 2.

On AMD systems it is implemented using IBS (up to precise-level 2).
The precise modifier works with event types 0x76 (cpu-cycles, CPU
clocks not halted) and 0xC1 (micro-ops retired). Both events map to
IBS execution sampling (IBS op) with the IBS Op Counter Control bit
(IbsOpCntCtl) set respectively (see AMD64 Architecture Programmer’s
Manual Volume 2: System Programming, 13.3 Instruction-Based
Sampling). Examples to use IBS:

 perf record -a -e cpu-cycles:p ...    # use ibs op counting cycles
 perf record -a -e r076:p ...          # same as -e cpu-cycles:p
 perf record -a -e r0C1:p ...          # use ibs op counting micro-ops

RAW HARDWARE EVENT DESCRIPTOR
-----------------------------
Even when an event is not available in a symbolic form within perf right now,
it can be encoded in a per processor specific way.

For instance For x86 CPUs NNN represents the raw register encoding with the
layout of IA32_PERFEVTSELx MSRs (see [Intel® 64 and IA-32 Architectures Software Developer's Manual Volume 3B: System Programming Guide] Figure 30-1 Layout
of IA32_PERFEVTSELx MSRs) or AMD's PerfEvtSeln (see [AMD64 Architecture Programmer’s Manual Volume 2: System Programming], Page 344,
Figure 13-7 Performance Event-Select Register (PerfEvtSeln)).

Note: Only the following bit fields can be set in x86 counter
registers: event, umask, edge, inv, cmask. Esp. guest/host only and
OS/user mode flags must be setup using <<EVENT_MODIFIERS, EVENT
MODIFIERS>>.

Example:

If the Intel docs for a QM720 Core i7 describe an event as:

  Event  Umask  Event Mask
  Num.   Value  Mnemonic    Description                        Comment

  A8H      01H  LSD.UOPS    Counts the number of micro-ops     Use cmask=1 and
                            delivered by loop stream detector  invert to count
                                                               cycles

raw encoding of 0x1A8 can be used:

 perf stat -e r1a8 -a sleep 1
 perf record -e r1a8 ...

You should refer to the processor specific documentation for getting these
details. Some of them are referenced in the SEE ALSO section below.

PARAMETERIZED EVENTS
--------------------

Some pmu events listed by 'perf-list' will be displayed with '?' in them. For
example:

  hv_gpci/dtbp_ptitc,phys_processor_idx=?/

This means that when provided as an event, a value for '?' must
also be supplied. For example:

  perf stat -C 0 -e 'hv_gpci/dtbp_ptitc,phys_processor_idx=0x2/' ...

OPTIONS
-------

Without options all known events will be listed.

To limit the list use:

. 'hw' or 'hardware' to list hardware events such as cache-misses, etc.

. 'sw' or 'software' to list software events such as context switches, etc.

. 'cache' or 'hwcache' to list hardware cache events such as L1-dcache-loads, etc.

. 'tracepoint' to list all tracepoint events, alternatively use
  'subsys_glob:event_glob' to filter by tracepoint subsystems such as sched,
  block, etc.

. 'pmu' to print the kernel supplied PMU events.

. If none of the above is matched, it will apply the supplied glob to all
  events, printing the ones that match.

. As a last resort, it will do a substring search in all event names.

One or more types can be used at the same time, listing the events for the
types specified.

Support raw format:

. '--raw-dump', shows the raw-dump of all the events.
. '--raw-dump [hw|sw|cache|tracepoint|pmu|event_glob]', shows the raw-dump of
  a certain kind of events.

SEE ALSO
--------
linkperf:perf-stat[1], linkperf:perf-top[1],
linkperf:perf-record[1],
http://www.intel.com/Assets/PDF/manual/253669.pdf[Intel® 64 and IA-32 Architectures Software Developer's Manual Volume 3B: System Programming Guide],
http://support.amd.com/us/Processor_TechDocs/24593_APM_v2.pdf[AMD64 Architecture Programmer’s Manual Volume 2: System Programming]