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2014-06-10glib-compat.h: add new thread API emulation on top of pre-2.31 APIMichael Tokarev1-39/+11
Thread API changed in glib-2.31 significantly. Before that version, conditionals and mutexes were only allocated dynamically, using _new()/_free() interface. in 2.31 and up, they're allocated statically as regular variables, and old interface is deprecated. (Note: glib docs says the new interface is available since version 2.32, but it was actually introduced in version 2.31). Create the new interface using old primitives, by providing non-opaque definitions of the base types (GCond and GMutex) using GOnces. Replace #ifdeffery around GCond and GMutex in trace/simple.c and coroutine-gthread.c too because it does not work anymore with the new glib-compat.h. Signed-off-by: Michael Tokarev <mjt@tls.msk.ru> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> [Use GOnce to support lazy initialization; introduce CompatGMutex and CompatGCond. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-09trace: Multi-backend tracingLluís Vilanova1-18/+1
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>
2014-06-09trace: add pid field to simpletrace recordStefan Hajnoczi1-2/+6
It is useful to know the QEMU process ID when working with traces from multiple VMs. Although the trace filename may contain the pid, tools that aggregate traces or even trace globally need somewhere to record the pid. There is a reserved field in the trace event header struct that we can use. It is not necessary to bump the simpletrace file format version number because it has already been incremented for the QEMU 2.1 release cycle in commit "trace: [simple] Bump up log version number". Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-05-07trace: [simple] Bump up log version numberLluís Vilanova1-1/+1
The following tracetool cleanup changes the event numbering policy. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-25osdep: initialize glib threads in all QEMU toolsStefan Hajnoczi1-9/+0
glib versions prior to 2.31.0 require an explicit g_thread_init() call to enable multi-threading. Failure to initialize threading causes glib to take single-threaded code paths without synchronization. For example, the g_slice allocator will crash due to race conditions. Fix this for all QEMU tool programs (qemu-nbd, qemu-io, qemu-img) by moving the g_thread_init() call from vl.c:main() into a new osdep.c:thread_init() constructor function. thread_init() has __attribute__((constructor)) and is automatically invoked by the runtime during startup. We can now drop the "simple" trace backend's g_thread_init() call since thread_init() already called it. Note that we must keep coroutine-gthread.c's g_thread_init() call which is located in a constructor function. There is no guarantee for constructor function ordering so thread_init() may only be called later. Reported-by: Mario de Chenno <mario.dechenno@unina2.it> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-01-27trace: add glib 2.32+ static GMutex supportStefan Hajnoczi1-7/+16
The GStaticMutex API was deprecated in glib 2.32. We cannot switch over to GMutex unconditionally since we would drop support for older glib versions. But the deprecated API warnings during build are annoying so use static GMutex when possible. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-01-27trace: [simple] Do not include "trace/simple.h" in generated tracer headersLluís Vilanova1-0/+1
The header is not necessary, given that the simple backend does not define any inlined tracing routines. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28trace: [simple] Port to generic event information and new control interfaceLluís Vilanova1-28/+7
The backend is forced to dump event numbers using 64 bits, as TraceEventID is an enum. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-02-12trace: deal with deprecated glib thread functionsStefan Hajnoczi1-0/+18
g_thread_create() was deprecated in favor of g_thread_new() and g_cond_new() was deprecated in favor of GCond initialization. If the host has glib 2.31 or newer, avoid using the deprecated functions. This patch solves compiler warnings that are generated when glib's deprecated functions are used. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1360676045-9204-3-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-12trace: use glib atomic int typesStefan Hajnoczi1-3/+3
Juan reported that RHEL 6.4 hosts give compiler warnings because we use unsigned int while glib prototypes use volatile gint in trace/simple.c. trace/simple.c:223: error: pointer targets in passing argument 1 of 'g_atomic_int_compare_and_exchange' differ in signedness These variables are only accessed with glib atomic int functions so let's play it by the book and use volatile gint. Reported-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1360676045-9204-2-git-send-email-stefanha@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-05trace: Clean up the "try to update atomic until it worked" loopsMarkus Armbruster1-13/+5
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>
2013-02-05trace: Direct access of atomics is verboten, use the APIMarkus Armbruster1-4/+5
The GLib Reference Manual says: It is very important that all accesses to a particular integer or pointer be performed using only this API and that different sizes of operation are not mixed or used on overlapping memory regions. Never read or assign directly from or to a value -- always use this API. 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>
2013-02-05trace: Fix simple trace dropped event record for big endianMarkus Armbruster1-8/+8
We use atomic operations to keep track of dropped events. Inconveniently, GLib supports only int and void * atomics, but the counter dropped_events is uint64_t. Can't stop commit 62bab732: a quick (gint *)&dropped_events bludgeons the compiler into submission. That cast is okay only when int is exactly 64 bits wide, which it commonly isn't. If int is even wider, we clobber whatever follows dropped_events. Not worth worrying about, as none of the machines that interest us have such morbidly obese ints. That leaves the common case: int narrower than 64 bits. Harmless on little endian hosts: we just don't access the most significant bits of dropped_events. They remain zero. On big endian hosts, we use only the most significant bits of dropped_events as counter. The least significant bits remain zero. However, we write out the full value, which is the correct counter shifted left a bunch of places. Fix by changing the variables involved to int. There's another, equally suspicious-looking (gint *)&trace_idx argument to g_atomic_int_compare_and_exchange(), but that one casts unsigned *, so it's okay. But it's also superfluous, because GLib's atomic int operations work just fine for unsigned. Drop it. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2012-12-19misc: move include files to include/qemu/Paolo Bonzini1-1/+1
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-08-14trace/simple: Replace asprintf by g_strdup_printfStefan Weil1-10/+4
asprintf is not available for all hosts. g_strdup_printf is more portable and simplifies the code because if does not need error handling. The static variable does not need an explicit assignment to be NULL. Cc: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-08-14trace: avoid pointer aliasing in trace_record_finish()Harsh Prateek Bora1-5/+4
Declaring a TraceRecord on the stack works fine. No need for a uint8_t array and pointer aliasing. Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-08-14trace: drop unused TraceBufferRecord->next_tbuf_idx fieldHarsh Prateek Bora1-2/+0
Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-08-14trace: remove unnecessary write_to_buffer() typecastingHarsh Prateek Bora1-3/+3
The buffer argument is void* so it is not necessary to cast. Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-08-14trace: rename TraceRecordHeader to TraceLogHeaderHarsh Prateek Bora1-2/+2
The TraceRecordHeader is really the header for the entire trace log file. It's not per-record header so make this obvious by renaming it. Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-07-19Simpletrace v2: Support multiple arguments, strings.Harsh Prateek Bora1-94/+159
Existing simpletrace backend allows to trace at max 6 args and does not support strings. This newer tracelog format gets rid of fixed size records and therefore allows to trace variable number of args including strings. Sample trace with strings: v9fs_version 0.000 tag=0xffff id=0x64 msize=0x2000 version=9P2000.L v9fs_version_return 6.705 tag=0xffff id=0x64 msize=0x2000 version=9P2000.L Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-07-19monitor: remove unused do_info_traceHarsh Prateek Bora1-18/+0
Going forward with simpletrace v2 variable size trace records, we cannot have a generic function to print trace event info and therefore this interface becomes invalid. As per Stefan Hajnoczi: "This command is only available from the human monitor. It's not very useful because it historically hasn't been able to pretty-print events or show them in the right order (we use a ringbuffer but it prints them out from index 0). Therefore, I don't think we're under any obligation to keep this command around. No one has complained about it's limitations - I think this is a sign that no one has used it. I'd be okay with a patch that removes it." Ref: http://lists.gnu.org/archive/html/qemu-devel/2012-01/msg01268.html Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-06-08trace/simple.c: fix deprecated glib2 interfaceHarsh Prateek Bora1-1/+4
Signed-off-by: Harsh Prateek Bora <harsh@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12trace: make trace_thread_create() use its function argJun Koi1-1/+1
This patch makes trace_thread_create() to use its function arg to initialize thread. The other choice is to make this a function to use void arg, but i prefer this way. Signed-off-by: Jun Koi <junkoi2004@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-12-20g_thread_init users: don't call it if glib >= 2.31Alon Levy1-0/+5
since commit f9b29ca03 included in release 2.31 (docs below say 2.32 but that is not correct) and onwards g_thread_init is deprecated and calling it is not required: http://developer.gnome.org/glib/unstable/glib-Deprecated-Thread-APIs.html#g-thread-init g_thread_init has been deprecated since version 2.32 and should not be used in newly-written code. This function is no longer necessary. The GLib threading system is automatically initialized at the start of your program. Fixes bulid failure when warnings are treated as errors on fedora 17. I only tested the change to vl.c, and copy pasted to the two other locations (couldn't decide if a wrapper for calling g_thread_init is uglier). Signed-off-by: Alon Levy <alevy@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-11-01trace: Add wildcard trace event supportMark Wu1-2/+17
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: use binary file open mode in simpletraceStefan Hajnoczi1-1/+1
For Windows portability the simple trace backend must use the 'b' file open mode. This prevents the stdio library from mangling 0x0a/0x0d newline characters. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-09-21trace: portable simple trace backend using glibStefan Hajnoczi1-26/+48
Convert the simple trace backend to glib so that it works under Windows. We cannot use pthread directly but glib provides portable abstractions. Also use glib atomics instead of newish gcc builtins which may not be supported on Windows toolchains. Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-09-01trace: add "-trace events" argument to control initial stateLluís1-1/+2
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: separate trace event control and query routines from the simple backendLluís1-8/+8
Generalize the 'st_print_trace_events' and 'st_change_trace_event_state' into backend-specific 'trace_print_events' and 'trace_event_set_state' (respectively) in the "trace/control.h" file. Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
2011-09-01trace: avoid conditional code compilation during option parsingLluís1-4/+6
A default implementation for backend-specific routines is provided in "trace/default.c", which backends can override by setting "trace_default=no" in "configure". Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
2011-09-01trace: move backend-specific code into the trace/ directoryLluís1-0/+355
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>