trace: [ust] Fix format string computation in tcg-enabled events

TCG-enabled events start with two format strings. Delay per-argument format
computation until requested ('Event.formats').

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
trace: docs: add trace file description

When user used the trace print command from docs/tracing.txt:
  ./scripts/simpletrace.py trace-events trace-*

the user maybe be misled by the "trace-*", because if user
directly copy the comand line to run, there alway print the
bored message:
"usage: ./scripts/simpletrace.py <trace-events> <trace-file>"

then we should describe that the "trace-*" represented.

Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
trace: [qmp] Add commands to query and control event tracing state

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 20140825111957.31112.31733.stgit@fimbulvetr.bsc.es
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
trace: [hmp] Reimplement "trace-event" and "info trace-events" using QMP

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 20140825112002.31112.60143.stgit@fimbulvetr.bsc.es
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
trace-events: drop orphan virtio_blk_data_plane_complete_request

This trace event has not been in use since commit
b002254dbd4c19a01f29790f840f983803e26893 ("virtio-blk: Unify
{non-,}dataplane's request handlings").

Cc: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1411394595-15300-2-git-send-email-stefanha@redhat.com
trace-events: drop orphan usb_mtp_data_out

This trace event was added in commit
840a178c94dbd3f5b5550fb8621620cb761de72d ("usb: mtp filesharing") but
never used.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1411394595-15300-3-git-send-email-stefanha@redhat.com
trace-events: drop orphan iscsi trace events

iscsi_aio_write16_cb, iscsi_aio_writev, iscsi_aio_read16_cb, and
iscsi_aio_readv have not not been in use since commit
063c3378a9e3c25cc0afac3c72e4823d0621e352 ("block/iscsi: introduce
bdrv_co_{readv, writev, flush_to_disk}").

These were the only trace events in block/iscsi.c so drop the the
trace.h include.

Cc: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1411394595-15300-4-git-send-email-stefanha@redhat.com
trace: tighten up trace-events regex to fix bad parse

Use \w for properties and trace event names since they are both drawn
from [a-zA-Z0-9_] character sets.

The .* for matching properties was too aggressive and caused the
following failure with foo(int rc) "(this is a test)":

  Traceback (most recent call last):
    File "scripts/tracetool.py", line 139, in <module>
      main(sys.argv)
    File "scripts/tracetool.py", line 134, in main
      binary=binary, probe_prefix=probe_prefix)
    File "scripts/tracetool/__init__.py", line 334, in generate
      events = _read_events(fevents)
    File "scripts/tracetool/__init__.py", line 262, in _read_events
      res.append(Event.build(line))
    File "scripts/tracetool/__init__.py", line 225, in build
      return Event(name, props, fmt, args, arg_fmts)
    File "scripts/tracetool/__init__.py", line 185, in __init__
      % ", ".join(unknown_props))
  ValueError: Unknown properties: foo(int, rc)

Cc: Lluís Vilanova <vilanova@ac.upc.edu>
Reported-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1411468626-20450-1-git-send-email-stefanha@redhat.com
cleanup-trace-events.pl: Tighten search for trace event call

The script can get fooled too easily.  For instance, it finds
trace_megasas_io_read_start when looking for trace_megasas_io_read,
and incorrectly concludes that event megasas_io_read is used.

Supply -w to git-grep to tighten the search.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1411476811-24251-2-git-send-email-armbru@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
trace-events: Drop unused megasas trace event

Event megasas_io_read was added in commit e8f943c, but never used.
Drop it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1411476811-24251-3-git-send-email-armbru@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
trace-events: Drop orphaned monitor trace event

Event monitor_protocol_event is unused since commit 7517517.  Drop it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1411476811-24251-4-git-send-email-armbru@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
trace-events: Fix comments pointing to source files

A few files have been renamed without updating their comment here.  A
few events have been added in the wrong place.  Clean that up.

Comments with no space after the '#' look ugly and confuse
cleanup-trace-events.pl.  Insert a space.

scripts/cleanup-trace-events.pl is now happy again.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1411476811-24251-5-git-send-email-armbru@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
trace: install trace-events file

Install the ./trace-events file into the data directory.  This file
contains the list of trace events that were built into QEMU at
compile-time.

The file is a handy reference for the set of trace events that the QEMU
binary was built with.  It is also needed by the simpletrace.py tool
that parses binary trace data either emitted from QEMU when built with
--enable-trace-backend=simple or by the SystemTap simpletrace script
that QEMU provides.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1411486175-3017-1-git-send-email-stefanha@redhat.com
scripts/tracetool: don't barf on formats with precision

This only affects lttng user space tracing at the moment.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
ohci: Split long traces to smaller ones

Recent traces rework introduced 2 tracepoints with 13 and 20
arguments. When dtrace backend is selected
(--enable-trace-backend=dtrace), compile fails as
sys/sdt.h defines DTRACE_PROBE up to DTRACE_PROBE12 only.

This splits long tracepoints.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
ohci: drop computed flags from trace events

This exceeded the trace argument limit for LTTNG UST and wasn't really
needed as the flags value is stored anyway. Dropping this fixes the
compile failure for UST. It can probably be merged with the previous
trace shortening patch.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Merge remote-tracking branch 'remotes/stefanha/tags/tracing-pull-request' into staging

# gpg: Signature made Fri 26 Sep 2014 11:59:34 BST using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"

* remotes/stefanha/tags/tracing-pull-request:
  ohci: drop computed flags from trace events
  ohci: Split long traces to smaller ones
  scripts/tracetool: don't barf on formats with precision
  trace: install trace-events file
  trace-events: Fix comments pointing to source files
  trace-events: Drop orphaned monitor trace event
  trace-events: Drop unused megasas trace event
  cleanup-trace-events.pl: Tighten search for trace event call
  trace: tighten up trace-events regex to fix bad parse
  trace-events: drop orphan iscsi trace events
  trace-events: drop orphan usb_mtp_data_out
  trace-events: drop orphan virtio_blk_data_plane_complete_request
  trace: [hmp] Reimplement "trace-event" and "info trace-events" using QMP
  trace: [qmp] Add commands to query and control event tracing state
  trace: docs: add trace file description
  trace: [ust] Fix format string computation in tcg-enabled events

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>