perf-eh_elf/Documentation/perf-kvm.txt
Linus Torvalds 16c00db4bb Merge tag 'afs-fixes-20180514' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS fixes from David Howells:
 "Here's a set of patches that fix a number of bugs in the in-kernel AFS
  client, including:

   - Fix directory locking to not use individual page locks for
     directory reading/scanning but rather to use a semaphore on the
     afs_vnode struct as the directory contents must be read in a single
     blob and data from different reads must not be mixed as the entire
     contents may be shuffled about between reads.

   - Fix address list parsing to handle port specifiers correctly.

   - Only give up callback records on a server if we actually talked to
     that server (we might not be able to access a server).

   - Fix some callback handling bugs, including refcounting,
     whole-volume callbacks and when callbacks actually get broken in
     response to a CB.CallBack op.

   - Fix some server/address rotation bugs, including giving up if we
     can't probe a server; giving up if a server says it doesn't have a
     volume, but there are more servers to try.

   - Fix the decoding of fetched statuses to be OpenAFS compatible.

   - Fix the handling of server lookups in Cache Manager ops (such as
     CB.InitCallBackState3) to use a UUID if possible and to handle no
     server being found.

   - Fix a bug in server lookup where not all addresses are compared.

   - Fix the non-encryption of calls that prevents some servers from
     being accessed (this also requires an AF_RXRPC patch that has
     already gone in through the net tree).

  There's also a patch that adds tracepoints to log Cache Manager ops
  that don't find a matching server, either by UUID or by address"

* tag 'afs-fixes-20180514' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Fix the non-encryption of calls
  afs: Fix CB.CallBack handling
  afs: Fix whole-volume callback handling
  afs: Fix afs_find_server search loop
  afs: Fix the handling of an unfound server in CM operations
  afs: Add a tracepoint to record callbacks from unlisted servers
  afs: Fix the handling of CB.InitCallBackState3 to find the server by UUID
  afs: Fix VNOVOL handling in address rotation
  afs: Fix AFSFetchStatus decoder to provide OpenAFS compatibility
  afs: Fix server rotation's handling of fileserver probe failure
  afs: Fix refcounting in callback registration
  afs: Fix giving up callbacks on server destruction
  afs: Fix address list parsing
  afs: Fix directory page locking
2018-05-15 10:48:36 -07:00

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perf-kvm(1)
===========
NAME
----
perf-kvm - Tool to trace/measure kvm guest os
SYNOPSIS
--------
[verse]
'perf kvm' [--host] [--guest] [--guestmount=<path>
[--guestkallsyms=<path> --guestmodules=<path> | --guestvmlinux=<path>]]
{top|record|report|diff|buildid-list} [<options>]
'perf kvm' [--host] [--guest] [--guestkallsyms=<path> --guestmodules=<path>
| --guestvmlinux=<path>] {top|record|report|diff|buildid-list|stat} [<options>]
'perf kvm stat [record|report|live] [<options>]
DESCRIPTION
-----------
There are a couple of variants of perf kvm:
'perf kvm [options] top <command>' to generates and displays
a performance counter profile of guest os in realtime
of an arbitrary workload.
'perf kvm record <command>' to record the performance counter profile
of an arbitrary workload and save it into a perf data file. We set the
default behavior of perf kvm as --guest, so if neither --host nor --guest
is input, the perf data file name is perf.data.guest. If --host is input,
the perf data file name is perf.data.kvm. If you want to record data into
perf.data.host, please input --host --no-guest. The behaviors are shown as
following:
Default('') -> perf.data.guest
--host -> perf.data.kvm
--guest -> perf.data.guest
--host --guest -> perf.data.kvm
--host --no-guest -> perf.data.host
'perf kvm report' to display the performance counter profile information
recorded via perf kvm record.
'perf kvm diff' to displays the performance difference amongst two perf.data
files captured via perf record.
'perf kvm buildid-list' to display the buildids found in a perf data file,
so that other tools can be used to fetch packages with matching symbol tables
for use by perf report. As buildid is read from /sys/kernel/notes in os, then
if you want to list the buildid for guest, please make sure your perf data file
was captured with --guestmount in perf kvm record.
'perf kvm stat <command>' to run a command and gather performance counter
statistics.
Especially, perf 'kvm stat record/report' generates a statistical analysis
of KVM events. Currently, vmexit, mmio (x86 only) and ioport (x86 only)
events are supported. 'perf kvm stat record <command>' records kvm events
and the events between start and end <command>.
And this command produces a file which contains tracing results of kvm
events.
'perf kvm stat report' reports statistical data which includes events
handled time, samples, and so on.
'perf kvm stat live' reports statistical data in a live mode (similar to
record + report but with statistical data updated live at a given display
rate).
OPTIONS
-------
-i::
--input=<path>::
Input file name.
-o::
--output=<path>::
Output file name.
--host::
Collect host side performance profile.
--guest::
Collect guest side performance profile.
--guestmount=<path>::
Guest os root file system mount directory. Users mounts guest os
root directories under <path> by a specific filesystem access method,
typically, sshfs. For example, start 2 guest os. The one's pid is 8888
and the other's is 9999.
#mkdir ~/guestmount; cd ~/guestmount
#sshfs -o allow_other,direct_io -p 5551 localhost:/ 8888/
#sshfs -o allow_other,direct_io -p 5552 localhost:/ 9999/
#perf kvm --host --guest --guestmount=~/guestmount top
--guestkallsyms=<path>::
Guest os /proc/kallsyms file copy. 'perf' kvm' reads it to get guest
kernel symbols. Users copy it out from guest os.
--guestmodules=<path>::
Guest os /proc/modules file copy. 'perf' kvm' reads it to get guest
kernel module information. Users copy it out from guest os.
--guestvmlinux=<path>::
Guest os kernel vmlinux.
-v::
--verbose::
Be more verbose (show counter open errors, etc).
STAT REPORT OPTIONS
-------------------
--vcpu=<value>::
analyze events which occur on this vcpu. (default: all vcpus)
--event=<value>::
event to be analyzed. Possible values: vmexit, mmio (x86 only),
ioport (x86 only). (default: vmexit)
-k::
--key=<value>::
Sorting key. Possible values: sample (default, sort by samples
number), time (sort by average time).
-p::
--pid=::
Analyze events only for given process ID(s) (comma separated list).
STAT LIVE OPTIONS
-----------------
-d::
--display::
Time in seconds between display updates
-m::
--mmap-pages=::
Number of mmap data pages (must be a power of two) or size
specification with appended unit character - B/K/M/G. The
size is rounded up to have nearest pages power of two value.
-a::
--all-cpus::
System-wide collection from all CPUs.
-p::
--pid=::
Analyze events only for given process ID(s) (comma separated list).
--vcpu=<value>::
analyze events which occur on this vcpu. (default: all vcpus)
--event=<value>::
event to be analyzed. Possible values: vmexit,
mmio (x86 only), ioport (x86 only).
(default: vmexit)
-k::
--key=<value>::
Sorting key. Possible values: sample (default, sort by samples
number), time (sort by average time).
--duration=<value>::
Show events other than HLT (x86 only) or Wait state (s390 only)
that take longer than duration usecs.
--proc-map-timeout::
When processing pre-existing threads /proc/XXX/mmap, it may take
a long time, because the file may be huge. A time out is needed
in such cases.
This option sets the time out limit. The default value is 500 ms.
SEE ALSO
--------
linkperf:perf-top[1], linkperf:perf-record[1], linkperf:perf-report[1],
linkperf:perf-diff[1], linkperf:perf-buildid-list[1],
linkperf:perf-stat[1]