Commit Graph

113 Commits

Author SHA1 Message Date
Philippe Mathieu-Daudé
9ab5a24b52 scripts: Remove unused python imports
Reported-by: LGTM code review
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20181108143422.15955-1-philmd@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-01-17 17:52:40 -02:00
Fabiano Rosas
8fbc12f324 tracetool: Include thread id information in log backend
Currently the log backend prints the process id of QEMU at the start
of each output line, but since threads share the same PID there is no
clear distinction between their outputs.

Having the thread id present in the log makes it easier to see when
output comes from different threads. E.g.:

12423@1538597569.672527:qemu_mutex_lock waiting on mutex 0x1103ee60 (/root/qemu/util/main-loop.c:236)
...
12430@1538597569.503928:qemu_mutex_unlock released mutex 0x1103ee60 (/root/qemu/cpus.c:1238)
12431@1538597569.503937:qemu_mutex_locked taken mutex 0x1103ee60 (/root/qemu/cpus.c:1257)
^here

In the above, 12423 is the main process id and 12430 & 12431 are the
two vcpu threads.

 (qemu) info cpus
 * CPU #0: thread_id=12430
   CPU #1: thread_id=12431

Suggested-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-12-12 10:04:59 +00:00
Philippe Mathieu-Daudé
82c4f87e0e trace: Fix format string for the struct timeval members casted to size_t
This fixes when using GCC with -Wformat-signedness:

    migration/trace.h: In function ‘_nocheck__trace_dirty_bitmap_load_success’:
    migration/trace.h:6368:24: error: format ‘%zd’ expects argument of type ‘signed size_t’, but argument 3 has type ‘long unsigned int’ [-Werror=format=]
      qemu_log("%d@%zd.%06zd:dirty_bitmap_load_success " "" "\n",
                   ~~^
                   %ld
    migration/trace.h:6370:18:
               (size_t)_now.tv_sec, (size_t)_now.tv_usec
               ~~~~~~~~~~~~~~~~~~~
    migration/trace.h:6368:30: error: format ‘%zd’ expects argument of type ‘signed size_t’, but argument 4 has type ‘long unsigned int’ [-Werror=format=]
      qemu_log("%d@%zd.%06zd:dirty_bitmap_load_success " "" "\n",
                       ~~~~^
                       %06ld
    migration/trace.h:6370:39:
               (size_t)_now.tv_sec, (size_t)_now.tv_usec
                                    ~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-06-29 15:04:18 +01:00
Stefan Hajnoczi
ec09f87753 trace: forbid floating point types
Only one existing trace event uses a floating point type.  Unfortunately
float and double cannot be supported since SystemTap does not have
floating point types.

Remove float and double from the whitelist and document this limitation.
Update the migrate_transferred trace event to use uint64_t instead of
double.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-id: 20180621150254.4922-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-06-27 11:09:29 +01:00
Daniel P. Berrangé
73ff061032 trace: only permit standard C types and fixed size integer types
Some trace backends will compile code based on the declared trace
events. It should not be assumed that the backends can resolve any QEMU
specific typedefs. So trace events should restrict their argument
types to the standard C types and fixed size integer types. Any complex
pointer types can be declared as "void *" for purposes of trace events,
since nothing will be dereferencing these pointer arguments.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180308155524.5082-3-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-03-12 11:10:20 +00:00
Daniel P. Berrangé
86b5aacfb9 trace: include filename when printing parser error messages
Improves error messages from:

  ValueError: Error on line 72: need more than 1 value to unpack

To

  ValueError: Error at /home/berrange/src/virt/qemu/trace-events:72:
    need more than 1 value to unpack

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180306154650.24075-1-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-03-12 11:10:20 +00:00
Peter Maydell
be0aa7ac89 log-for-trace.h: Split out parts of log.h used by trace.h
A persistent build problem we see is where a source file
accidentally omits the #include of log.h. This slips through
local developer testing because if you configure with the
default (log) trace backend trace.h will pull in log.h for you.
Compilation fails only if some other backend is selected.

To make this error cause a compile failure regardless of
the configured trace backend, split out the parts of log.h
that trace.h requires into a new log-for-trace.h header.
Since almost all manual uses of the log.h functions will
use constants or functions which aren't in log-for-trace.h,
this will let us catch missing #include "qemu/log.h" more
consistently.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180213140029.8308-1-peter.maydell@linaro.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-03-12 11:10:20 +00:00
Jon Emil Jahren
61b01bbc6c tracetool: For ust trace bool type as ctf_integer
Previously functions having arguments of type bool was not traced
properly. The bool arguments were missing from the trace.

Signed-off-by: Jon Emil Jahren <jonemilj@gmail.com>
Message-id: 20180129041648.30884-3-jonemilj@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-02-19 13:09:44 +00:00
Jon Emil Jahren
fb1a66bc01 tracetool: Update argument format regex to non-greedy star
Using the greedy star matching, arguments like "...%"PRIx64 caused issues
for functions with multiple PRI formats.

The issue was only seen with the ust backend, as it is the only one
using the format regex.

The result for many functions was that the arguments coming after the
greedy star end was left out of the tracepoint, and in some cases some
of the arguments that was traced had the wrong format.

Signed-off-by: Jon Emil Jahren <jonemilj@gmail.com>
Message-id: 20180129041648.30884-2-jonemilj@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-02-19 13:09:44 +00:00
Stefan Hajnoczi
24f4d3d3ae tracetool: report error on foo() instead of foo(void)
C functions with no arguments must be declared foo(void) instead of
foo().  The tracetool argument list parser has never accepted an empty
argument list.  This patch adds a clear error message for this error
case.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20180110202553.31889-4-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-01-29 10:34:55 +00:00
Stefan Hajnoczi
6e497fa1b1 tracetool: clarify that "formats" means "format strings"
The terminology used by tracetool is not consistent with C sprintf or
docs/devel/tracing.txt.  The word "formats" is sometimes used to mean
"format strings".

This patch clarifies comments and error messages that contain this word.

Note that the error message lines are longer than 80 characters but I
have not wrapped them to aid grepping.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20180110202553.31889-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-01-29 10:34:55 +00:00
Stefan Hajnoczi
5069b56189 tracetool: prefix parse errors with line numbers
Include the file line number in the message that is printed when
trace-events parse errors are raised.

[Use enumerate(fobj, 1) to avoid having to increment a 0-based index
later, as suggested by Eric Blake.
--Stefan]

Suggested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20180110202553.31889-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-01-29 10:34:55 +00:00
Stefan Hajnoczi
d6b76d6805 trace: use static event ID mapping in simpletrace.stp
This is a partial revert of commit
7f1b588f20 ("trace: emit name <-> ID
mapping in simpletrace header"), which broke the SystemTap flight
recorder because event mapping records may not be present in the ring
buffer when the trace is analyzed.  This means simpletrace.py
--no-header does not know the event ID mapping needed to pretty-print
the trace.

Instead of numbering events dynamically, use a static event ID mapping
as dictated by the event order in the trace-events-all file.

The simpletrace.py script also uses trace-events-all so the next patch
will fix the simpletrace.py --no-header option to take advantage of this
knowledge.

Cc: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170815084430.7128-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-15 12:50:29 +01:00
Stefan Hajnoczi
3932ef3ffb trace: add TRACE_<event>_BACKEND_DSTATE()
QEMU keeps track of trace event enabled/disabled state and provides
monitor commands to inspect and modify the "dstate".  SystemTap and
LTTng UST maintain independent enabled/disabled states for each trace
event, the other backends rely on QEMU dstate.

Introduce a new per-event macro that combines backend-specific dstate
like this:

  #define TRACE_MY_EVENT_BACKEND_DSTATE() ( \
      QEMU_MY_EVENT_ENABLED() || /* SystemTap */ \
      tracepoint_enabled(qemu, my_event) /* LTTng UST */ || \
      false)

This will be used to extend trace_event_get_state() in the next patch.

[Daniel Berrange pointed out that QEMU_MY_EVENT_ENABLED() must be true
by default, not false.  This way events will fire even if the DTrace
implementation does not implement the SystemTap semaphores feature.

Ubuntu Precise uses lttng-ust-dev 2.0.2 which does not have
tracepoint_enabled(), so we need a compatibility wrapper to keep Travis
builds passing.
--Stefan]

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170731140718.22010-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

fixup! trace: add TRACE_<event>_BACKEND_DSTATE()
2017-08-01 12:07:48 +01:00
Daniel P. Berrange
ea1ff54f7d trace: ensure unique function / variable names per .stp file
The simpletrace compatibility code for systemtap creates a
function and some global variables for mapping to event ID
numbers. We generate multiple -simpletrace.stp files though,
one per target and systemtap considers functions & variables
to be globally scoped, not per file. So if trying to use the
simpletrace compat probes, systemtap will complain:

 # stap -e 'probe qemu.system.arm.simpletrace.visit_type_str { print( "hello")}'
 semantic error: conflicting global variables: identifier 'event_name_to_id_map' at /usr/share/systemtap/tapset/qemu-aarch64-simpletrace.stp:3:8
        source: global event_name_to_id_map
                       ^
 identifier 'event_name_to_id_map' at /usr/share/systemtap/tapset/qemu-system-arm-simpletrace.stp:3:8
        source: global event_name_to_id_map
                       ^

 WARNING: cross-file global variable reference to identifier 'event_name_to_id_map' at /usr/share/systemtap/tapset/qemu-system-arm-simpletrace.stp:3:8 from: identifier 'event_name_to_id_map' at /usr/share/systemtap/tapset/qemu-aarch64-simpletrace.stp:8:21
 source:     if (!([name] in event_name_to_id_map)) {
                             ^
 WARNING: cross-file global variable reference to identifier 'event_next_id' at /usr/share/systemtap/tapset/qemu-system-arm-simpletrace.stp:4:8 from: identifier 'event_next_id' at :9:38
 source:         event_name_to_id_map[name] = event_next_id
                                              ^

We already have a string used to prefix probe names, so just
replace '.' with '_' to get a function / variable name prefix

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170728133657.5525-1-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-01 10:36:30 +01:00
Lluís Vilanova
1ff7b53196 trace: [tcg, trivial] Re-align generated code
Last patch removed a nesting level in generated code. Re-align all code
generated by backends to be 4-column aligned.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-id: 149915824586.6295.17820926011082409033.stgit@frigg.lan
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-07-17 13:11:13 +01:00
Lluís Vilanova
864a2178d4 trace: [tcg] Do not generate TCG code to trace dynamically-disabled events
If an event is dynamically disabled, the TCG code that calls the
execution-time tracer is not generated.

Removes the overheads of execution-time tracers for dynamically disabled
events. As a bonus, also avoids checking the event state when the
execution-time tracer is called from TCG-generated code (since otherwise
TCG would simply not call it).

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-id: 149915799921.6295.13067154430923434035.stgit@frigg.lan
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-07-17 13:11:12 +01:00
Daniel P. Berrange
f3fddaf60b trace: disallow more than 10 arguments per trace event
The UST trace backend can only cope with upto 10 arguments. To ensure we
don't exceed the limit when UST is not compiled in, disallow more than
10 arguments upfront.

This prevents the case where:

  commit 0fc8aec7de
  Author: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
  Date:   Tue Apr 18 10:20:20 2017 +0800

    COLO-compare: Optimize tcp compare trace event

    Optimize two trace events as one, adjust print format make
    it easy to read. rename trace_colo_compare_pkt_info_src/dst
    to trace_colo_compare_tcp_info.

regressed the fix done in

  commit 2dfe5113b1
  Author: Alex Bennée <alex.bennee@linaro.org>
  Date:   Fri Oct 28 14:25:59 2016 +0100

    net: split colo_compare_pkt_info into two trace events

    It seems there is a limit to the number of arguments a UST trace event
    can take and at 11 the previous trace command broke the build. Split the
    trace into a src pkt and dst pkt trace to fix this.

    Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
    Message-id: 20161028132559.8324-1-alex.bennee@linaro.org
    Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
    Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Now we get an immediate fail even when UST is disabled:

  GEN     net/trace.h
Traceback (most recent call last):
  File "/home/berrange/src/virt/qemu/scripts/tracetool.py", line 154, in <module>
    main(sys.argv)
  File "/home/berrange/src/virt/qemu/scripts/tracetool.py", line 145, in main
    events.extend(tracetool.read_events(fh))
  File "/home/berrange/src/virt/qemu/scripts/tracetool/__init__.py", line 307, in read_events
    event = Event.build(line)
  File "/home/berrange/src/virt/qemu/scripts/tracetool/__init__.py", line 244, in build
    event = Event(name, props, fmt, args)
  File "/home/berrange/src/virt/qemu/scripts/tracetool/__init__.py", line 196, in __init__
    "argument count" % name)
ValueError: Event 'colo_compare_tcp_info' has more than maximum permitted argument count
Makefile:96: recipe for target 'net/trace.h-timestamp' failed

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20170426153900.21066-1-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-05-08 09:38:30 -04:00
Stefan Hajnoczi
7609ffb919 trace: fix tcg tracing build breakage
Commit 0ab8ed18a6 ("trace: switch to
modular code generation for sub-directories") forgot to convert "tcg"
trace events to the modular code generation approach where each
sub-directory has its own trace-events file.

This patch fixes compilation for "tcg" trace events.  Currently they are
only used in the root ./trace-events file.

"tcg" trace events can only be used in the root ./trace-events file for
the time being.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20170327131718.18268-1-stefanha@redhat.com
Suggested-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-03-28 11:07:46 +01:00
Daniel P. Berrange
0ab8ed18a6 trace: switch to modular code generation for sub-directories
Introduce rules in the top level Makefile that are able to generate
trace.[ch] files in every subdirectory which has a trace-events file.

The top level directory is handled specially, so instead of creating
trace.h, it creates trace-root.h. This allows sub-directories to
include the top level trace-root.h file, without ambiguity wrt to
the trace.g file in the current sub-dir.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170125161417.31949-7-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-01-31 17:11:18 +00:00
Fam Zheng
db4df20de8 trace: Fix 'char **' compilation error in simple backend
Currently, the generated function body will do "strlen(arg)" but the
argument could be 'char **' or 'char * const *'. Avoid that by excluding
such cases in is_string check.

Reported by patchew's "make docker-test-mingw@fedora".

Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1477453806-21097-1-git-send-email-famz@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-10-27 19:24:15 +01:00
Daniel P. Berrange
80dd5c4918 trace: introduce a formal group name for trace events
The declarations in the generated-tracers.h file are
assuming there's only ever going to be one instance
of this header, as they are not namespaced. When we
have one header per event group, if a single source
file needs to include multiple sets of trace events,
the symbols will all clash.

This change thus introduces a '--group NAME' arg to the
'tracetool' program. This will cause all the symbols in
the generated header files to be given a unique namespace.

If no group is given, the group name 'common' is used,
which is suitable for the current usage where there is
only one global trace-events file used for code generation.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 1475588159-30598-21-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:54:53 +02:00
Daniel P. Berrange
9096b78a38 trace: push reading of events up a level to tracetool main
Move the reading of events out of the 'tracetool.generate'
method and into tracetool.main, so that the latter is not
tied to generating from a single source of events.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-19-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:54:52 +02:00
Daniel P. Berrange
d1b97bcea3 trace: rename _read_events to read_events
The _read_events method is used by callers outside of
its module, so should be a public method, not private.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-18-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:54:52 +02:00
Daniel P. Berrange
347701879c trace: get rid of generated-events.h/generated-events.c
Currently the generated-events.[ch] files contain the
event dstates, constants and TraceEvent structs, while the
generated-tracers.[ch] files contain the actual trace
probe logic. With the removal of usage of the event enums
from the API there is no longer any compelling reason for
the separation between these files. The generated-events.h
content is only ever needed from the generated-tracers.[ch]
files.

The enums/constants/structs from generated-events.[ch] are
thus moved into the generated-tracers.[ch], so that there
is one less file to be generated.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-17-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:54:52 +02:00
Daniel P. Berrange
ca3fa0e88f trace: dynamically allocate event IDs at runtime
Instead of having the code generator assign event IDs and
event VCPU IDs, assign them when the events are registered
at runtime. This will allow code to be generated from
individual trace-events without having to figure out
globally unique numbering at build time.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-16-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:54:52 +02:00
Daniel P. Berrange
fe4db84d49 trace: provide mechanism for registering trace events
Remove the notion of there being a single global array
of trace events, by introducing a method for registering
groups of events.

The module_call_init() needs to be invoked at the start
of any program that wants to make use of the trace
support. Currently this covers system emulators qemu-nbd,
qemu-img and qemu-io.

[Squashed the following fix from Daniel P. Berrange
<berrange@redhat.com>:

linux-user/bsd-user: initialize trace events subsystem

The bsd-user/linux-user programs make use of the CPU emulation
code and this now requires that the trace events subsystem
is enabled, otherwise it'll crash trying to allocate an empty
trace events bitmap for the CPU object.

--Stefan]

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-14-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:52:50 +02:00
Daniel P. Berrange
7f1b588f20 trace: emit name <-> ID mapping in simpletrace header
Currently simpletrace assumes that events are given IDs
starting from 0, based on the order in which they appear
in the trace-events file, with no gaps. When the
trace-events file is split up, this assumption becomes
problematic.

To deal with this, extend the simpletrace format so that
it outputs a table of event name <-> ID mappings. That
will allow QEMU to assign arbitrary IDs to events without
breaking simpletrace parsing.

The v3 simple trace format was

  FILE HEADER
  EVENT TRACE RECORD 0
  EVENT TRACE RECORD 1
  ...
  EVENT TRACE RECORD N

The v4 simple trace format is now

  FILE HEADER
  EVENT MAPPING RECORD 0
  EVENT MAPPING RECORD 1
  ...
  EVENT MAPPING RECORD M
  EVENT TRACE RECORD RECORD 0
  EVENT TRACE RECORD RECORD 1
  ...
  EVENT TRACE RECORD N

Although this shows all the mapping records being emitted
upfront, this is not required by the format. While the main
simpletrace backend will emit all mappings at startup,
the systemtap simpletrace.stp script will emit the mappings
at first use. eg

  FILE HEADER
  ...
  EVENT MAPPING RECORD 0
  EVENT TRACE RECORD RECORD 0
  EVENT TRACE RECORD RECORD 1
  EVENT MAPPING RECORD 1
  EVENT TRACE RECORD RECORD 2
  ...
  EVENT TRACE RECORD N

This is more space efficient given that most trace records
only include a subset of events.

In modifying the systemtap simpletrace code, a 'begin' probe
was added to emit the trace event header, so you no longer
need to add '--no-header' when running simpletrace.py for
systemtap generated trace files.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-12-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:35:54 +02:00
Daniel P. Berrange
ef4c9fc854 trace: remove the TraceEventID and TraceEventVCPUID enums
The TraceEventID and TraceEventVCPUID enums constants are
no longer actually used for anything critical.

The TRACE_EVENT_COUNT limit is used to determine the size
of the TraceEvents array, and can be removed if we just
NULL terminate the array instead.

The TRACE_VCPU_EVENT_COUNT limit is used as a magic value
for marking non-vCPU events, and also for declaring the
size of the trace dstate mask in the CPUState struct.
The former usage can be replaced by a dedicated constant
TRACE_EVENT_VCPU_NONE, defined as (uint32_t)-1. For the
latter usage, we can simply define a constant for the
number of VCPUs, avoiding the need for the full enum.

The only other usages of the enum values can be replaced
by accesing the id/vcpu_id fields via the named TraceEvent
structs.

Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-11-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:35:54 +02:00
Daniel P. Berrange
79218be42b trace: give each trace event a named TraceEvent struct
Currently we only expose a TraceEvent array, which must
be indexed via the TraceEventID enum constants. This
changes the generator to expose a named TraceEvent
instance for each event, with an _EVENT suffix.

Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-10-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:35:54 +02:00
Daniel P. Berrange
99672c7167 trace: remove duplicate control.h includes in generated-tracers.h
The format/h.py file adds an include for control.h to
generated-tracers.h. ftrace, log and syslog, then
add more duplicate includes for control.h.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-8-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:35:54 +02:00
Daniel P. Berrange
9397740244 trace: remove global 'uint16 dstate[]' array
Instead of having a global dstate array, declare a single
'uint16 TRACE_${EVENT_NAME}_DSTATE' variable for each
trace event. Record a pointer to this variable in the
TraceEvent struct too.

By turning trace_event_get_state_dynamic_by_id into a
macro, this still hits the fast path, and cache affinity
is ensured by declaring all the uint16 vars adjacent to
each other.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-7-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:35:54 +02:00
Paul Durrant
0a85241756 trace: add syslog tracing backend
This patch adds a tracing backend which sends output using syslog().
The syslog backend is limited to POSIX compliant systems.

openlog() is called with facility set to LOG_DAEMON, with the LOG_PID
option. Trace events are logged at level LOG_INFO.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Message-id: 1470318254-29989-1-git-send-email-paul.durrant@citrix.com
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-09-05 13:47:01 -04:00
Lluís Vilanova
40b9cd25f7 trace: Conditionally trace events based on their per-vCPU state
Events with the 'vcpu' property are conditionally emitted according to
their per-vCPU state. Other events are emitted normally based on their
global tracing state.

Note that the per-vCPU condition check applies to all tracing backends.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-18 18:23:12 +01:00
Lluís Vilanova
17f7ac75df trace: Identify events with the 'vcpu' property
A new event attribute 'cpu_id' is added to have a separate ID
space ('TRACE_VCPU_*') for all events with the 'vcpu' property.

These are later used to identify which events are enabled on each vCPU.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-18 18:13:54 +01:00
Paolo Bonzini
33c11879fd qemu-common: push cpu.h inclusion out of qemu-common.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:29 +02:00
Markus Armbruster
c80f6e9caa Clean up includes some more
Manually drop redundant includes that scripts/clean-includes misses,
e.g. because they're hidden in generator programs, or they use the
wrong kind of delimiter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:16 +01:00
Lluís Vilanova
4ade0541de trace: Add a proper API to manage auto-generated events from the 'tcg' property
Formalizes the existence of the 'event_trans' and 'event_exec' event
attributes, which until now were monkey-patched only when necessary.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 145640558759.20978.6374959404425591089.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:34:38 +00:00
Lluís Vilanova
3d211d9f4d trace: Add 'vcpu' event property to trace guest vCPU
This property identifies events that trace vCPU-specific information.

It adds a "CPUState*" argument to events with the property, identifying
the vCPU raising the event. TCG translation events also have a
"TCGv_env" implicit argument that is later used as the "CPUState*"
argument at execution time.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 145641861797.30295.6991314023181842105.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:27:10 +00:00
Lluís Vilanova
bc9beb47c7 trace: Add helper function to cast event arguments
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 145641860680.30295.1873612736245870753.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:27:09 +00:00
Lluís Vilanova
56797b1fbc trace: Remove unnecessary intermediate event copies
The current code forces the use of a chain of ".original" dereferences,
which looks odd.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 145641858988.30295.7223459456488075843.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:27:09 +00:00
Lluís Vilanova
3596f524d4 trace: Extend API to manage event arguments
Lets the user manage event arguments as a list, and simplifies argument
concatenation.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 145641858432.30295.3069911069472672646.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:27:09 +00:00
Peter Maydell
3174c64bb7 tracetool: Include osdep.h in generated-ust.c
When generating the trace/generated-ust.c source file, make sure
it includes osdep.h as its first include.

This fixes compilation with --enable-trace-backends=ust

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1456240661-15422-1-git-send-email-peter.maydell@linaro.org
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-23 15:43:30 +00:00
Peter Maydell
2aef8c9134 scripts/tracetool: Include qemu/osdep.h in generated .c files
Include qemu/osdep.h as the first include in generated .c files,
so they don't implicitly rely on some other included header
to pull it in.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-16 14:29:27 +00:00
Paolo Bonzini
ed7f5f1d8d trace: convert stderr backend to log
[Also update .travis.yml --enable-trace-backends=stderr
--Stefan]

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-id: 1452174932-28657-10-git-send-email-den@openvz.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-03 10:37:10 +00:00
Paolo Bonzini
585ec7273e trace: track enabled events in a separate array
This is more cache friendly on the fast path, where we already have
the event id available.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-02-03 09:19:09 +00:00
Stefan Hajnoczi
0b7e89b103 trace: add DTrace reserved words for .d files
DTrace on Mac OS X fails due to trace events using 'self' as an argument
name:

  GEN   trace/generated-tracers-dtrace.h
dtrace: failed to compile script trace/generated-tracers-dtrace.dtrace: line 1330: syntax error, unexpected DT_KEY_SELF, expecting ) near "self"
make: *** [trace/generated-tracers-dtrace.h] Error 1

Filter argument names according to the list of DTrace .d file reserved
keywords.

Note that DTrace on Mac and Linux still do not work after this patch.
There are additional build issues remaining.

Reported-by: Henk Poley <henkpoley@gmail.com>
Tested-by: Henk Poley <henkpoley@gmail.com>
Cc: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-03-02 15:39:43 -06:00
Dr. David Alan Gilbert
dd9fe29c80 trace: Print PID and time in stderr traces
When debugging migration it's useful to know the PID of
each trace message so you can figure out if it came from the source
or the destination.

Printing the time makes it easy to do latency measurements or timings
between trace points.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 1421746875-9962-1-git-send-email-dgilbert@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-02-06 10:27:22 +00:00
Christoph Seifert
776ec96f79 Tracing: Fix simpletrace.py error on tcg enabled binary traces
simpletrace.py does not recognize the tcg option while reading trace-events  file. In result simpletrace does not work on binary traces and tcg enabled events. Moved transformation of tcg enabled events to _read_events() which is used by simpletrace.

Signed-off-by: Christoph Seifert <christoph.seifert@posteo.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-18 14:05:58 +00:00
Alex Bennée
931f53e184 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>
2014-09-26 09:34:39 +01:00