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2014-06-09trace: Multi-backend tracingLluís Vilanova1-2/+2
Adds support to compile QEMU with multiple tracing backends at the same time. For example, you can compile QEMU with: $ ./configure --enable-trace-backends=ftrace,dtrace Where 'ftrace' can be handy for having an in-flight record of events, and 'dtrace' can be later used to extract more information from the system. This patch allows having both available without recompiling QEMU. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-02-19Update documentation for LTTng ust tracingMohamad Gebai1-0/+36
Signed-off-by: Mohamad Gebai <mohamad.gebai@polymtl.ca> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-06-14build: do not use TARGET_ARCHPaolo Bonzini1-1/+1
TARGET_ARCH is generally wrong to use, there are better variables provided in config-target.mak. The right one is usually TARGET_NAME (previously TARGET_ARCH2), but for bsd-user we can also use TARGET_ABI_DIR for consistency with linux-user. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1370349928-20419-4-git-send-email-pbonzini@redhat.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2013-05-03trace: document ftrace backendEiichi Tsukata1-0/+16
Add documentation of ftrace backend. Signed-off-by: Eiichi Tsukata <eiichi.tsukata.xh@hitachi.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28trace: Provide a detailed event control interfaceLluís Vilanova1-26/+18
This interface decouples event obtaining from interaction. Events can be obtained through three different methods: * identifier * name * simple wildcard pattern Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-02-05trace: Fix location of simpletrace.py in docsMarkus Armbruster1-2/+2
Missed when commit 4c3b5a48 moved it. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2012-11-16trace: Remove "info trace" from documentsLiming Wang1-9/+0
commit 88affa1c monitor: remove unused do_info_trace has removed "info trace" function from monitor, so remove it from documents. Signed-off-by: Liming Wang <walimisdev@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2012-11-16trace: document '-' syntax for disabling eventsStefan Hajnoczi1-0/+4
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2012-03-12docs: correct ./configure line in tracing.txtJun Koi1-1/+1
This patch corrects the configure's trace option in docs/tracing.txt. Signed-off-by: Jun Koi <junkoi2004@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12trace: Provide a per-event status define for conditional compilationLluís Vilanova1-6/+40
Adds a 'TRACE_${NAME}_ENABLED' preprocessor define for each tracing event in "trace.h". This lets the user conditionally compile code with a relatively high execution cost that is only necessary when producing the tracing information for an event that is enabled. Note that events using this define will probably have the "disable" property by default, in order to avoid such costs on regular builds. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-11-01trace: Add wildcard trace event supportMark Wu1-1/+8
A basic wildcard matching is supported in both the monitor command "trace-event" and the events list file. That means you can enable/disable the events having a common prefix in a batch. For example, virtio-blk trace events could be enabled using: trace-event virtio_blk_* on Signed-off-by: Mark Wu <wudxw@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-09-21trace: Update docs to use example events that existLluís Vilanova1-7/+9
The events 'qemu_malloc' and 'qemu_free' used in the examples no longer exist, so use 'qemu_vmalloc' and 'qemu_vfree' instead. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-09-21trace: allow trace events with string argumentsStefan Hajnoczi1-5/+3
String arguments are useful for producing human-readable traces without post-processing (e.g. stderr backend). Although the simple backend cannot handles strings all others can. Strings should be allowed and the simple backend can be extended to support them. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-09-17trace: allow PRI*64 at beginning and ending of format stringStefan Hajnoczi1-4/+1
The tracetool parser only picks up PRI*64 and other format string macros when enclosed between double quoted strings. Lift this restriction by extracting everything after the closing ')' as the format string: cpu_set_apic_base(uint64_t val) "%016"PRIx64 ^^ ^^ One trick here: it turns out that backslashes in the format string like "\n" were being interpreted by echo(1). Fix this by using the POSIX printf(1) command instead. Although it normally does not make sense to include backslashes in trace event format strings, an injected newline causes tracetool to emit a broken header file and I want to eliminate cases where broken output is emitted, even if the input was bad. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-09-01trace: [stderr] add support for dynamically enabling/disabling eventsLluís1-5/+0
Uses the generic interface provided in "trace/control.h" in order to provide a programmatic interface as well as command line and monitor controls. Signed-off-by: Fabien Chouteau <chouteau@adacore.com> Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
2011-09-01trace: [simple] disable all trace points by defaultLluís1-3/+8
Note that this refers to the backend-specific state (whether the output must be generated), not the event "disabled" property (which always uses the "nop" backend). Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
2011-09-01trace: always use the "nop" backend on events with the "disable" keywordLluís1-10/+15
Any event with the keyword/property "disable" generates an empty trace event using the "nop" backend, regardless of the current backend. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
2011-09-01trace: add "-trace events" argument to control initial stateLluís1-0/+4
The "-trace events" argument can be used to provide a file with a list of trace event names that will be enabled prior to starting execution, thus providing early tracing. This saves the user from manually toggling event states through the monitor interface or whichever backend-specific interface. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
2011-09-01trace: always compile support for controlling and querying trace event statesLluís1-18/+30
The current interface is generic for this small set of operations, and thus other backends can easily modify the "trace/control.c" file to add their own implementation. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
2011-09-01trace: generalize the "property" concept in the trace-events fileLluís1-2/+2
This adds/modifies the following functions: * get_name: Get _only_ the event name * has_property: Return whether an event has a property (keyword before the event name) Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
2011-04-26docs/tracing.txt: minor documentation fixesLluís1-9/+9
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-04-26docs: Trace events must not expect pointer dereferencingStefan Hajnoczi1-0/+5
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-03-07simpletrace: Thread-safe tracingStefan Hajnoczi1-5/+0
Trace events outside the global mutex cannot be used with the simple trace backend since it is not thread-safe. There is no check to prevent them being enabled so people sometimes learn this the hard way. This patch restructures the simple trace backend with a ring buffer suitable for multiple concurrent writers. A writeout thread empties the trace buffer when threshold fill levels are reached. Should the writeout thread be unable to keep up with trace generation, records will simply be dropped. Each time events are dropped a special record is written to the trace file indicating how many events were dropped. The event ID is 0xfffffffffffffffe and its signature is dropped(uint32_t count). Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-03-06docs: Update stderr and simple backend, add systemtap backendStefan Hajnoczi1-4/+26
The following additions to the tracing documentation are included: 1. Move "stderr" backend documentation to top-level and out of "simple" backend. Include hints on when this backend is useful. 2. Document the "simple" backend thread-safety limitation. 3. Document the "dtrace" backend for SystemTap. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-01-29New trace-event backend: stderrFabien Chouteau1-0/+5
This backend sends trace events to standard error output during the emulation. Also add a "--list-backends" option to tracetool, so configure script can display the list of available backends. Signed-off-by: Fabien Chouteau <chouteau@adacore.com> Acked-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-10-20trace: Format strings must begin/end with double quotesStefan Hajnoczi1-1/+4
Document the restriction that format strings must begin and end with double quotes. This is for easy parsing since we don't run cpp over trace-events. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-10-09trace: Use portable format stringsStefan Hajnoczi1-0/+4
It is not portable to use "%ld" for int64_t because int64_t may have type long on 64-bit platforms and long long on 32-bit platforms. Use the standard library PRId64 macros to keep format strings portable. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-09-09trace: Add user documentationStefan Hajnoczi1-0/+177
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
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