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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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()
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>
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>
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>
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>
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>
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>
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>
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>
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>
